Gas up: A cyclometalated iridium complex is found to catalyze the dehydrogenation of various benzofused N-heterocycles, thus releasing H₂. Driven by as low as 0.1 mol % catalyst, the reaction affords quinolines, indoles, quinoxalines, isoquinolines, and β-carbolines in high yields.

[Communication]
Jianjun Wu, Dinesh Talwar, Steven Johnston, Ming Yan, Jianliang Xiao
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201300292. Read article.

Line up for synthesis! In a recent report the Leigh group described a rotaxane-based setup for the sequence-specific synthesis of small peptides, which runs automatically once started. This molecular machine combines elements from both chemical and biochemical peptide (bio-)syntheses, which are discussed in this Highlight.

[Highlight]
Jordi Bertran-Vicente, Christian P. R. Hackenberger
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201301825. Read article.

Experiments and computations are reported of how stretching a polymer containing an ester moiety affects the kinetics of its basic hydrolysis (see picture). DFT computations of complete conformational ensembles of three homologous esters suggest that a stretching force stabilizes the tetrahedral intermediate and the second transition state (TS) but has no effect on the relative energy of the first TS.

[Communication]
Sergey Akbulatov, Yancong Tian, Eugene Kapustin, Roman Boulatov
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201300746. Read article.

Losing ligands rapidly: Pt^IV complexes with haloacetato ligands can hydrolyze rapidly under biological conditions (pH 7 and 37 °C, see scheme) and the rate increases with increasing pH value. Possible mechanisms for this hydrolysis are examined using H₂¹⁸O and ESI-MS analysis.

[Communication]
Ezequiel Wexselblatt, Eylon Yavin, Dan Gibson
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201300640. Read article.

Ganging up against the bad guys: Nanofibers of 1 efficiently inhibited the growth of glioblastoma cells but exhibited little acute toxicity toward a neuronal cell line. The selective cytotoxicity probably stems from the Warburg effect of cancer cells and the existence of microtubule-stabilizing proteins in neurons. Supramolecular nanofibers that can interrupt the self-organization of proteins may have potential as nanomedicines for the treatment of cancer.

[Communication]
Yi Kuang, Bing Xu
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201302658. Read article.

No strain, no gain! The first transition metal-catalyzed enantioselective α-alkylation of cyclobutanones is reported. This method employs palladium catalysis and an electron deficient PHOX type ligand to afford all-carbon α-quaternary cyclobutanones in good to excellent yields and enantioselectivities (see scheme).

[Communication]
Corey M. Reeves, Christian Eidamshaus, Jimin Kim, Brian M. Stoltz
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201301815. Read article.

In control: A highly selective carbocyclization/borylation of allenynes with bis(pinacolato)diboron (B₂pin₂) under palladium catalysis and with p-benzoquinone (BQ) as the oxidant was developed. The use of either LiOAc·2 H₂O with 1,2-dichloroethane (DCE) as the solvent or BF₃·Et₂O together with THF is crucial for the selective formation of borylated trienes and vinylallenes, respectively.

[Communication]
Youqian Deng, Teresa Bartholomeyzik, Jan-E. Bäckvall
Angew. Chem. Int. Ed., May 17, 2013, DOI: 10.1002/anie.201301167. Read article.

Robert Kretschmer, Zhe-Chen Wang, Maria Schlangen, Drs. h. c. Helmut Schwarz*

Crime scene: N–H bond activation. When ammonia gets in the crosshairs of [Al₂O₃]·⁺ the reaction is not limited to a single hydrogen-atom transfer, double hydrogen abstraction takes place as well and free nitrene is liberated at room temperature. These results are confirmed by mass spectrometric and theoretical investigations.

Published online, DOI: 10.1002/anie.201302506 – Read now

The standard model for molecular electrical p-doping of organic semiconductors (OSCs) assumes integer charge transfer between OSC and dopant. Here, it is contrasted to an alternative model based on intermolecular complex formation between OSC and dopant. Systematically varying the acceptor strength of prototypical dopants in a matrix of a solution processible OSC allowed discriminating the two models. Determining the actual structure of intermolecular complexes and correlating it with the optical and electronic properties of p-doped samples clearly favored the alternative model. Consequences for chemical design strategies of more efficient molecular dopants are deduced.

Coming soon.

Distinct differentiation: β,β-Disubstituted acrylic acids with sterically similar geminal diaryl groups can be hydrogenated with excellent enantioselectivities in the presence of a Rh^I complex formed in situ with two-component ligands, a chiral secondary phosphine oxide (SPO) and an achiral phosphine (Ph₃P). The sense of asymmetric induction was found to be controlled by the substrate configuration, thus allowing access to both enantiomers of the product with the same catalyst.

[Communication]
Yang Li, Kaiwu Dong, Zheng Wang, Kuiling Ding
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201302349. Read article.

Oxidation state control: The synthesis and characterization of two nitrate ester-functionalized electroactive tetrazine molecules (see example; N blue, Cl green, O red, C black) has been accomplished. The compounds are redox active and have desirable explosive properties. The reversible nature of their reduction could be utilized to control their chemical and physical properties.

[Communication]
David E. Chavez, Susan K. Hanson, Jacqueline M. Veauthier, Damon A. Parrish
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201302128. Read article.

[Book Review]
Katja Schmitz
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201303373. Read article.

Molecular crystal nanowires composed of an anthracene-9-(1,3-butadiene) derivative exhibit a rapid transition from straight to highly coiled structures when exposed to a pulse of visible light. The curling does not depend on the direction of light illumination and occurs for nanowires composed of either the E or Z isomer. The shape change is driven by an E&rlarr2;Z photoisomerization reaction that generates a mixture of isomers within a single nanowire.

[Communication]
Taehyung Kim, Muhanna K. Al-Muhanna, Salem D. Al-Suwaidan, Rabih O. Al-Kaysi, Christopher J. Bardeen
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201302323. Read article.

Molecular crystals: The structures and relative energies of glycine polymorphs are determined using dispersion corrections to PBE and PBEh density functionals. The picture shows a potential-energy surface for the a-b plane of γ-glycine obtained with density functional theory including many-body dispersion interactions.

[Communication]
Noa Marom, Robert A. DiStasio, Jr. Viktor Atalla, Sergey Levchenko, Anthony M. Reilly, James R. Chelikowsky, Leslie Leiserowitz, Alexandre Tkatchenko
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201301938. Read article.

Thin-film DNA–nanoparticle superlattices can be grown one layer at a time using a stepwise assembly process on DNA substrates. A new design rule for these programmable crystals is presented: the superlattice will adopt an orientation that maximizes complementary DNA interactions with a given crystal plane.

[Communication]
Andrew J. Senesi, Daniel J. Eichelsdoerfer, Robert J. Macfarlane, Matthew R. Jones, Evelyn Auyeung, Byeongdu Lee, Chad A. Mirkin
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201301936. Read article.

Photochemistry: A series of emissive gold(III) complexes with fluorene-containing cyclometalating ligands exhibits strong phosphorescence and long-lived excited states with emission quantum yields and lifetimes up to 58 % and 305 μs, respectively. These complexes can sensitize energy up-conversion of 9,10-diphenylanthracene (DPA; see picture) and display rich two-photon absorption properties (TPA; TTA=triplet–triplet annihilation).

[Communication]
Wai-Pong To, Kaai Tung Chan, Glenna So Ming Tong, Chensheng Ma, Wai-Ming Kwok, Xiangguo Guan, Kam-Hung Low, Chi-Ming Che
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201301149. Read article.

Wring it out: The title reaction proceeds in the presence of chiral Brønsted acid catalysts. This efficient ring-opening process features low catalyst loading, mild reaction conditions, broad functional group compatibility, high enantioselectivity, and the capability to generate chiral quaternary centers. The highly functionalized desymmetrization products are versatile chiral building blocks in organic synthesis.

[Communication]
Zhaobin Wang, Zhilong Chen, Jianwei Sun
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201300188. Read article.

Not too friendly with their neighbors: In the presence of certain polymers, such as methyl cellulose (MC), the rodlike tobacco mosaic virus (TMV) formed a superlattice in which the distance between the virus particles could be controlled within a wide range up to approximately 5 times their diameter. The spacing between the TMV particles in the superlattice showed a unique dependence on temperature and on the concentration of TMV (see picture).

[Communication]
Tao Li, Xingjie Zan, Randall E. Winans, Qian Wang, Byeongdu Lee
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201209299. Read article.

Duocarmycin-derived seco-cyclopropabenzindole (CBI) drugs have been shown to bind DNA and an aldehyde dehydrogenase (ALDH1A1) in lung cancer cells. The removal of the DNA-binding indole moiety results in a CBI compound that does not bind to DNA in whole cells but still exhibits remarkable cytotoxicity. This CBI compound has an increased affinity for ALDH1A1. Rh=rhodamine.

[Communication]
Tanja Wirth, Galina F. Pestel, Vanessa Ganal, Thomas Kirmeier, Ingrid Schuberth, Theo Rein, Professor Lutz F. Tietze, Professor Stephan A. Sieber
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201208941. Read article.

[Book Review]
Vlada Urlacher
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201303335. Read article.

Just SILP-ing through: Hydroaminomethylation of ethylene and diethylamine to diethylpropylamine is demonstrated as a continuous gas-phase reaction (see picture) using a supported ionic liquid phase (SILP) to immobilize the applied homogenous Rh-Xantphos catalyst. Highly selective and long-term stable (18 days) catalyst operation was obtained if the ionic liquid was of low basicity and lipophilicity combined with a porous activated carbon support.

[Communication]
Martin Johannes Schneider, Martin Lijewski, René Woelfel, Marco Haumann, Peter Wasserscheid
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201301365. Read article.

‘Dibal’lin’ on a budget: The enantioselective total syntheses of transtaganolides A–D are rapidly achieved by a highly diastereoselective Ireland–Claisen/Diels–Alder cascade reaction of an enantioenriched geraniol derivative (see scheme). Based on X-ray diffraction data, the absolute configuration of these metabolites is established and discussed within the context of existing biosynthetic hypotheses.

[Communication]
Hosea M. Nelson, Jonny R. Gordon, Scott C. Virgil, Brian M. Stoltz
Angew. Chem. Int. Ed., May 16, 2013, DOI: 10.1002/anie.201301212. Read article.

Gregor Kiefer, Lo[iuml]c Jeanbourquin, Kay Severin*

Catalysis with laughing gas: N₂O in combination with transition-metal catalysts allow the oxidative homo- and cross-coupling of Grignard reagents. The reactions can be performed under mild conditions despite the inert character of N₂O.

Published online, DOI: 10.1002/anie.201302471 – Read now

Enantioselective isomerization of γ-substituted primary allylic alcohols into the β-substituted aldehydes is catalyzed by the [RuCl₂{(S)-tol-binap}{(R)-dbapen}]–KOH system. The reaction is conducted with a substrate-to-catalyst molar ratio in the range of 100–2000 at 25°C for 0.5–1 h. A turnover number of about 1550 is achieved in the best case. A series of (E)- and (Z)-configurated aromatic and aliphatic allylic alcohols, including a simple primary alkyl-substituted compound (E)-3-methyl-2-hepten-1-ol, is transformed to the aldehydes in at least 99% ee. The plausible mechanism for this reaction, which is promoted by the hemilability of the dbapen–Ru chelate structure, is also discussed.

Coming soon.

A synthesis of the sesquiterpenoid antibiotic (+)-hongoquercin A using sequential site-specific C–H methylation and oxidation reactions is described. A key advancement toward this goal was the development of a ligand-accelerated C–H methylation reaction. This unique strategic disconnection enables the generation of a library of eight structurally diverse analogs, highlighting the utility of these reactions in the synthesis and modification of structurally complex molecules.

Coming soon.

Total control: The antibiotic BE-43472B with a unique bisanthraquinone structure has been synthesized in a completely stereocontrolled manner. The key steps are 1) a pinacol rearrangement to install the angular naphthyl group, 2) a diastereoselective methylation of a lactol derivative, and 3) the late-stage installation of the labile hydroxy group through an epoxide.

[Communication]
Yu Yamashita, Yoichi Hirano, Akiomi Takada, Hiroshi Takikawa, Keisuke Suzuki
Angew. Chem. Int. Ed., May 15, 2013, DOI: 10.1002/anie.201301591. Read article.

Crime scene: N-H bond activation. When ammonia gets in the crosshairs of [Al₂O₃]^.+ the reaction is not limited to a single hydrogen-atom transfer, double hydrogen abstraction takes place as well and free nitrene is liberated at room temperature. These results are confirmed by mass spectrometric and theoretical investigations.

[Communication]
Robert Kretschmer, Zhe-Chen Wang, Maria Schlangen, Helmut Schwarz
Angew. Chem. Int. Ed., May 15, 2013, DOI: 10.1002/anie.201302506. Read article.

Is that S-O? The title scaffolds have a highly active and properly differentiated S-O bond for the efficient synthesis of enantiopure sulfinamides. The method is practical, green, and has the potential to provide an economical commercial process for the synthesis of bulky sulfinamides.

[Communication]
Zhengxu S. Han, Melissa A. Herbage, Hari P. R. Mangunuru, Yibo Xu, Li Zhang, Jonathan T. Reeves, Joshua D. Sieber, Zhibin Li, Philomen DeCroos, Yongda Zhang, Guisheng Li, Ning Li, Shengli Ma, Nelu Grinberg, Xiaojun Wang, Navneet Goyal, Dhileep Krishnamurthy, Bruce Lu, Jinhua J. Song, Guijun Wang, Chris H. Senanayake
Angew. Chem. Int. Ed., May 15, 2013, DOI: 10.1002/anie.201301676. Read article.

André Nadler, Gregor Reither, Suihan Feng, Frank Stein, Sabine Reither, Rainer Müller, Carsten Schultz*

Caged compounds are designed to release biologically active signaling molecules with temporal, spatial, and even subcellular resolution. But how localized does the signal stay? Using the example of diacylglycerol, some signal responses (PKC) are shown to remain spatially distinct while other signals ([Ca²⁺]_i) spread across the entire cell. Surprisingly, this distribution patterns depend on the fatty acid composition of the lipid species.

Coming soon.

Alexander C. Filippou*, Yury N. Lebedev, Oleg Chernov, Martin Straßmann, Gregor Schnakenburg

Ligand swap: The exchange of N-heterocyclic carbene (NHC) ligands at Si^II centers is shown to provide access to a dicationic NHC complex of silicon(II), and an NHC adduct of the iodosilyliumylidene cation SiI⁺, [SiI(IiPr₂Me₂)(IDipp)]⁺ (see picture). Characterization studies led to the discovery of an unprecedented C–H···Si anagostic interaction for [SiI(IiPr₂Me₂)(IDipp)]⁺.

Coming soon.

A conceptually novel method for performing in situ separation and recycling of submicrometer-sized solid catalysts has been explored, which is based on the pH-triggered Pickering emulsion inversion. This method enables solid catalysts to be recycled 36 times without significant loss of activity. The developed method is distinguished from the conventional methods in respect of time and energy consumption, catalyst separation, and recycling effectiveness.

Coming soon.

Because of the higher electronegativity of hydrogen (2.20) compared to boron (2.04), hydrogen atoms bonded to boron are regarded as hydrides, and thus deprotonation does not seem feasible. The use of both an electrophilic cyclic (alkyl)(amino)carbene (CAAC) and of two electron-withdrawing nitrile groups, makes a neutral carbene-borohydride adduct acidic enough to be deprotonated by a strong base. The resulting (CAAC)-B(CN)₂^- anion is stable in the absence of air and moisture, and reacts with carbon and metal electrophiles at the boron center.

Coming soon.

Bis(indole) alkaloids analogues were prepared under mild conditions and in high yields through a gold-catalyzed cycloisomerization of 1,1-bis(indolyl)-5-alkynes (see scheme). The enantioselective version of this reaction gave the corresponding products in moderate to excellent yields (55–90 %), moderate to good ee values (48–96 %), and satisfactory regioselectivities (3.5:1→20:1).

[Communication]
Long Huang, Hai-Bin Yang, Di-Han Zhang, Zhen Zhang, Xiang-Ying Tang, Qin Xu, Min Shi
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201302632. Read article.

Only 10 seconds: Hydrocarbons and water do not mix under standard conditions, but they do mix freely at high temperature and high pressure near the gas/liquid critical point of water (T_c=374 °C, P_c=22.1 MPa). Quenching of homogeneous solutions of dodecane and water at such extreme conditions in the presence of a surfactant results in bottom-up formation of nanosized oil droplets in water in only 10 seconds.

[Communication]
Shigeru Deguchi, Nao Ifuku
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201301403. Read article.

Catalysis with laughing gas: N₂O in combination with transition-metal catalysts allow the oxidative homo- and cross-coupling of Grignard reagents. The reactions can be performed under mild conditions despite the inert character of N₂O.

[Communication]
Gregor Kiefer, Loïc Jeanbourquin, Kay Severin
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201302471. Read article.

Emulsion inversion, from water-in-oil (w/o) to oil-in-water (o/w), was accomplished by employing tetrahydropyran-containing ligands that undergo facile deprotection, converting the nanoparticles from hydrophobic to hydrophilic. These ligand-tailored nanoparticles were used to prepare w/o emulsions that were disrupted, and inverted, to o/w systems simply by lowering the solution pH. The inversion process could be triggered by light using a photoacid generator.

[Communication]
Irem Kosif, Mengmeng Cui, Thomas P. Russell, Todd Emrick
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201302112. Read article.

Oh, what a difference an S makes: A thioribose analogue (cADPtR, see scheme) of cyclic ADP-ribose (cADPR) was synthesized that is stable and has structural and electrostatic features similar to those of cADPR. cADPtR is the first stable equivalent of cADPR that is as active as cADPR in various cellular systems, making it useful for investigating Ca²⁺ ion-release signaling pathways.

[Communication]
Takayoshi Tsuzuki, Natsumi Sakaguchi, Takashi Kudoh, Satoshi Takano, Masato Uehara, Takashi Murayama, Takashi Sakurai, Minako Hashii, Haruhiro Higashida, Karin Weber, Andreas H. Guse, Tomoshi Kameda, Takatsugu Hirokawa, Yasuhiro Kumaki, Barry V. L. Potter, Hayato Fukuda, Mitsuhiro Arisawa, Satoshi Shuto
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201302098. Read article.

Fine print: The title technology is a continuous, roll-to-roll, high-resolution molding technology which allows the design and synthesis of precisely defined micro- and nanoparticles. This technology enables researchers to have unprecedented control over particle size, shape, chemical composition, cargo, modulus, and surface properties. Recent work involving the PRINT technology for application in the biomedical and material sciences is described.

[Minireview]
Jing Xu, Dominica H. C. Wong, James D. Byrne, Kai Chen, Charles Bowerman, Joseph M. DeSimone
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201209145. Read article.

Numerous honors were bestowed on Alfred Werner, who in 1913 was the first Swiss scientist to be awarded the Nobel Prize in Chemistry. This Essay gives an overview of Werner's scientific work and its significance beyond coordination chemistry.

[Essay]
Helmut Werner
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201208389. Read article.

My favorite book is Doktor Faustus. The natural talent I would like to be gifted with being able to improvise on the piano.

[Author Profile]

Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201207942. Read article.

De gustibus: β-homoDNA has the singular property of being able to pair with homochiral complements of opposite chirality, with a greater stability than that observed in the corresponding isochiral complexes. Relevant to etiological investigations on nucleic acid structure, these results suggest the existence of a relationship between carbohydrate structure and stereoselectivity of the hybridization processes of the corresponding nucleic acids.

[Communication]
Daniele D'Alonzo, Jussara Amato, Guy Schepers, Matheus Froeyen, Arthur Van Aerschot, Piet Herdewijn, Annalisa Guaragna
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201301659. Read article.

Calligraphic counter electrodes: An important photovoltaic application using FeS₂ nanocrystal (NC) pyrite ink to fabricate a counter electrode as an alternative to Pt in dye-sensitized solar cells is demonstrated. FeS₂ NC ink exhibits excellent electrochemical catalytic activity and remarkable electrochemical stability. ITO=indium-doped tin oxide.

[Communication]
Ying-Chiao Wang, Di-Yan Wang, You-Ting Jiang, Hsin-An Chen, Chia-Chun Chen, Kuo-Chuan Ho, Hung-Lung Chou, Chun-Wei Chen
Angew. Chem. Int. Ed., May 13, 2013, DOI: 10.1002/anie.201300401. Read article.

Photoswitchable inhibitors of protein–protein interactions have been applied to photoregulate clathrin-mediated endocytosis (CME) in living cells. These peptides, named traffic lights because they act as "stop" and "go" signals for membrane traffic, constitute a novel tool to control cell signaling in spatiotemporally defined patterns. Traffic light peptides can be used to dissect the role of CME in receptor internalization and in cell growth, division, and differentiation.

Coming soon.

Yusuke Kawanaka, Akihiro Shimizu, Tetsuro Shinada, Rika Tanaka, Yoshio Teki*

A radical solution: The photochemical instability and insolubility in organic solvents of pentacene derivatives prevent their use in molecular electronics. These issues were solved by using pentacene derivatives with stable radicals (Y=radical moiety, 2 and 4) that have a lifetime of 2077 min in organic solvents under ambient light. The corresponding nonradical pentacene derivatives (Y=radical precursor, 1 and 3) decay on exposure to light.

Coming soon.

Twice as good: Parallel electrochemical oxidation and reduction of a single parent polymer (P1) simultaneously provided two corresponding polymers (P2 and P3), which were easily separated. Upon UV irradiation, the color of the emissions of the P2 and P3 films were drastically different to that of P1 (left). Parallel reactions on a bipolar electrode afforded a multicolored gradient film (right).

[Communication]
Shinsuke Inagi, Hiroyuki Nagai, Ikuyoshi Tomita, Toshio Fuchigami
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201302251. Read article.

Chemical Matching: C2- or C3-alkynylated furans were selectively synthesized by using gold catalysis. Direct C–H alkynylation of furans was achieved with C2 selectivity, and a domino cyclization/alkynylation process starting from allenes gave C3-alkynylated products. The exact matching of the structure of the gold catalyst and an electrophilic hypervalent iodine reagent was essential for success.

[Communication]
Yifan Li, Jonathan P. Brand, Jérôme Waser
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201302210. Read article.

Highly functionalized cyclic and acyclic alkenylzinc reagents bearing functional groups such as aldehyde, keto, and ester groups were readily prepared by either direct zinc insertion in the presence of LiCl or by magnesium insertion in the presence of LiCl and ZnCl₂. Subsequent functionalization reactions like Negishi cross-couplings, acylations, and allylations were performed, furnishing polyfunctional compounds in excellent yields.

[Communication]
Christoph Sämann, Matthias A. Schade, Shigeyuki Yamada, Paul Knochel
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201302058. Read article.

Please pass the oxygen: A new method for the preparation of trans-α,β-epoxyketimines has been achieved through a copper-catalyzed rearrangement of (E)-α,β-unsaturated nitrones. The scope and tolerance of the method is evaluated and the synthetic utility of the products is demonstrated. The new transformation provides facile access to an unusual, densely functionalized intermediate that can be exploited for further synthetic application.

[Communication]
Dong-Liang Mo, Laura L. Anderson
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301963. Read article.

Less is more: An efficient synthesis of the anti-mitotic macrolide dictyostatin proceeds with a longest linear sequence of 14 steps, and allows the rapid production of multi-gram quantities of each of the three fragments from which the natural product is assembled in just four or five steps. The key step is a scalable one-step synthesis of the C(12)–C(14) and C(20)–C(22) stereotriads.

[Communication]
Stephen Ho, Cyril Bucher, James L. Leighton
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201302565. Read article.

Going (anti)viral: The first total synthesis of the antiviral (+)-schisanwilsonene A has been completed using a fully stereoselective tandem cyclization/1,5-migration/intermolecular cyclopropanation. The key reaction sequence is catalyzed by gold.

[Communication]
Morgane Gaydou, Ricarda E. Miller, Nicolas Delpont, Julien Ceccon, Antonio M. Echavarren
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201302411. Read article.

Smart stars: A novel star–star supramolecular architecture was self-assembled from a star-shaped adamantyl-terminated 8-arm poly(ethylene glycol) and a star-shaped poly(N-isopropylacrylamide) with a β-cyclodextrin core through inclusion complexation. The star–star supramolecules further self-aggregated into a 3D network in response to temperature change, forming a thermo-responsive reversible “smart” hydrogel.

[Communication]
Zhong-Xing Zhang, Kerh Li Liu, Jun Li
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301956. Read article.

Step by step: Electron- and hydrogen-transfer steps are documented IR-spectroelectrochemically and structurally for the H₂-producing oxidation of a dicarbonylcobalt hydride complex modified by the sterically protecting 1,1'-bis(diisopropylphosphino)ferrocene. The series complements the mechanism discussed for water-reducing cobalt compounds with less π-accepting ligands.

[Communication]
Michael J. Krafft, Martina Bubrin, Alexa Paretzki, Falk Lissner, Jan Fiedler, Stanislav Záliš, Wolfgang Kaim
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301706. Read article.

With (dumb)bells on: A variety of colloidal stereoisomers (all the same materials) have been prepared through evaporation of emulsions by using symmetric and asymmetric dumbbell-shaped particles (see figure). The colloid configurations are in good agreement with the results of computer simulations.

[Communication]
Bo Peng, Frank Smallenburg, Arnout Imhof, Marjolein Dijkstra, Alfons van Blaaderen
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301520. Read article.

New directions: The carboxylic acid functional group directs the ortho acylation of benzoic acids with carboxylic anhydrides in the presence of a rhodium catalyst (see scheme; cod=cyclo-1,5-octadiene). The acylation at the ortho position is complementary to the meta selectivity of Friedel–Crafts reactions. The resulting products can undergo protodecarboxylation to deliver an aryl ketone.

[Communication]
Patrizia Mamone, Grégory Danoun, Lukas J. Gooßen
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301328. Read article.

There’s the rub: Friction of single polymers on solid bodies in a liquid environment was investigated. Apart from expected mechanisms, such as slip and stick, a third nanoscale friction mechanism exists that is independent of normal force, velocity, and adsorbed polymer length. A model is proposed for this mechanism that is based on measurements with various polymers on topographically and chemically nanostructured surfaces.

[Communication]
Bizan N. Balzer, Markus Gallei, Moritz V. Hauf, Markus Stallhofer, Lorenz Wiegleb, Alexander Holleitner, Matthias Rehahn, Thorsten Hugel
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201301255. Read article.

Broadband visible-light harvesting over TiO₂ is achieved by introducing gold nanorods (Au NRs) as antennas based on localized surface plasmon resonance. Furthermore, surfactant removal is achieved by an HClO₄ oxidative method. Not only transversal but also longitudinal plasma of Au NRs can induce photooxidation of 2-propanol, which extends the light harvesting to the near-infrared region. Scale bar: 10 nm.

[Communication]
Lequan Liu, Shuxin Ouyang, Jinhua Ye
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201300239. Read article.

Performance by an oxidant in a leading role: In the electroless etching of silicon to form nanocrystalline porous-silicon thin films, the oxidant extracts one electron from the silicon valence band to initiate etching and then a second from the conduction band to suppress H₂ formation. This discovery overturns the conventional wisdom regarding the role of the oxidant in stain etching, the stoichiometry of which was derived from the UV/Vis spectra shown.

[Communication]
Kurt W. Kolasinski, William B. Barclay
Angew. Chem. Int. Ed., May 10, 2013, DOI: 10.1002/anie.201300755. Read article.

Deep-blue emitters based on cyclometalated platinum(II) complexes were synthesized, characterized, and used in organic light-emitting devices. The complexes with tetradentate ligands exhibited improved photophysical properties over iridium analogues, and one such compound achieved a peak external quantum efficiency (EQE) of 23.7 %.

[Communication]
Xiao-Chun Hang, Tyler Fleetham, Eric Turner, Jason Brooks, Jian Li
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302541. Read article.

Fluorine makes it possible! The regioselective nucleophilic substitution of (oligo)fluoropyridines with the appropriate amines and the subsequent catalytic hydrodefluorination paves the way to hitherto inaccessible aminopyridine derivatives which are of interest as new ligands. Up to four fluorine atoms can be removed regioselectively in one step in a reaction employing an inexpensive titanium precatalyst.

[Communication]
Gabriel Podolan, Dieter Lentz, Hans-Ulrich Reissig
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201301927. Read article.

Multifunctional nanomaterials: A new type of multilayer thin film containing alternating polyaniline layers and titania nanosheets was self-assembled (see picture). The film was used as photoelectrode which has n-type to p-type switchable semiconducting properties.

[Communication]
Brian Seger, Jonathan McCray, Aniruddh Mukherji, Xu Zong, Zheng Xing, Lianzhou Wang
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302062. Read article.

Inexpensive copper(I) catalysts allow the direct site-selective azidation (C-N bond formation) of C(sp²)-H bonds in electron-rich heteroarenes and readily available anilines (see scheme). The reaction occurs under remarkably mild conditions and has a broad substrate scope.

[Highlight]
Weifeng Song, Sergei I. Kozhushkov, Lutz Ackermann
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302015. Read article.

Modern chemistry with an old substituent: The introduction of the SCF₃ group into organic substrates is a challenging task because of harsh or specific synthetic methods. However, recent advances in the formation of C-SCF₃ bonds include the trifluoromethylthiolation with transition-metal-free systems or in the presence of palladium, nickel, or copper catalysts (see scheme).

[Highlight]
Anis Tlili, Thierry Billard
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201301438. Read article.

Small but bright—just right! Codoping with sodium enabled the synthesis of highly emissive and ultrasmall (<10 nm) CaF₂:Ln³⁺ nanoparticles that were effective as sensitive probes for the detection of soluble uPAR (an important tumor marker) by time-resolved fluorescence resonance energy transfer (FRET; see picture; FITC=fluorescein isothiocyanate). The nanoprobes were also used successfully for uPAR-targeted cancer-cell imaging.

[Communication]
Wei Zheng, Shanyong Zhou, Zhuo Chen, Ping Hu, Yongsheng Liu, Datao Tu, Haomiao Zhu, Renfu Li, Mingdong Huang, Xueyuan Chen
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302481. Read article.

A (photo)sensitive subject: Combined agarose gel electrophoresis and photochemical studies show that 5-methyl-2-pyrimidone (see picture), the main chromophore of (6-4) photoproducts, behaves as a DNA photosensitizer. These results raise the question of whether the (6-4) lesions can act as Trojan horses, enhancing CPD formation and oxidative damage.

[Communication]
Victoria Vendrell-Criado, Gemma M. Rodríguez-Muñiz, M. Consuelo Cuquerella, Virginie Lhiaubet-Vallet, Miguel A. Miranda
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302176. Read article.

Correlation of cluster and bulk structure: Electron-diffraction measurements of homonuclear 55-atom transition-metal cluster anions covering essentially all 3d and 4d elements show only four main structure families. Elements with the same bulk lattice morphology generally have a common cluster structure type. The cluster structure types differ in maximum atomic coordination numbers in analogy to the coordination numbers in the corresponding bulk lattices.

[Communication]
Thomas Rapps, Reinhart Ahlrichs, Eugen Waldt, Manfred M. Kappes, Detlef Schooss
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302165. Read article.

Slipping into a comfortable routine: Multilayered polymer thin films were assembled on particles immobilized in agarose by electrophoresis on the basis of various interactions. Core removal then led to robust capsules with different polymer compositions (see fluorescence image). This approach enables the versatile and routine assembly of nanometer- and micron-sized capsules and coated particles with very few processing steps.

[Communication]
Joseph J. Richardson, Hirotaka Ejima, Samuel L. Lörcher, Kang Liang, Philipp Senn, Jiwei Cui, Frank Caruso
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201302092. Read article.

α, β, γ: The title method employs a Mg/L catalyst which is well suited for the selective γ deprotonation and activation of linear α,β-unsaturated ketones for reaction with nitroalkenes. The reaction leads to a series of optically active cyclohexene ring systems bearing multiple functional groups, systems which are not easily accessible using other methodologies.

[Communication]
Dongxu Yang, Linqing Wang, Fengxia Han, Depeng Zhao, Bangzhi Zhang, Rui Wang
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201301146. Read article.

Two steps in one pot: An enzyme cascade consisting of a lyase and an (R)- or (S)-selective ω-transaminase (TA) provides (1R,2R)-norpseudoephedrine and (1R,2S)-norephedrine in only two steps. The intermediate is not isolated in this one-pot reaction and the products are obtained in high enantio- and diastereomeric purity. Moreover, the by-product from the second reaction can be recycled to serve as the substrate for the first reaction.

[Communication]
Torsten Sehl, Helen C. Hailes, John M. Ward, Rainer Wardenga, Eric von Lieres, Heike Offermann, Robert Westphal, Martina Pohl, Dörte Rother
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201300718. Read article.

Illuminating films of a porous chitosan matrix containing gold nanorods and thermosensitive micelles loaded with a chemical stimulates local photothermal conversion of the gold nanorods. The heat produced activates the ejection of the chemical from the micelles (see scheme), and causes the transient permeabilization of adjacent cell membranes, resulting in a selective cellular uptake of the released chemical with control over spatiotemporal parameters and dosage.

[Communication]
Paolo Matteini, Francesca Tatini, Lapo Luconi, Fulvio Ratto, Francesca Rossi, Giuliano Giambastiani, Roberto Pini
Angew. Chem. Int. Ed., May 09, 2013, DOI: 10.1002/anie.201207986. Read article.

Molecular crystal nanowires composed of an anthracene-9-(1,3-butadiene) derivative exhibit a rapid transition from straight to highly coiled structures when exposed to a pulse of visible light. The curling does not depend on the direction of the light illumination and occurs for nanowires composed of either the (E) or (Z) isomer. The shape change is driven by an E⇌Z photoisomerization reaction that generates a mixture of isomers within a single nanowire.

Received March 19, 2013, published online May 16, 2013, DOI: 10.1002/anie.201302323 – read now.

Did you read this article? Was it important to you? Let us know...

Despite over a century of numerous investigations on the very important hydrophobic effect, direct observation of the evolving roles of the different related contributions during multi-step hydrophobic assembly processes has remained experimentally inaccessible. This challenging problem was now addressed by using an unprecedented type of experiment based on the step-wise growth of a structurally well-defined organic aggregate within a water-soluble porous metal-oxide nanocapsule. Detailed thermodynamic data obtained reveal an evolving spectrum of different types of hydrophobic effects acting in context with sequential growth steps, which finally lead to the formation of a beautiful "micelle"-like n-butyrate-ion assembly with a practically water-free central cavity.

Coming soon.

I likes rearrangements: Hypervalent iodine compounds can be used as environmentally friendly, mild, and selective reagents for highly enantioselective rearrangements of alkenes. For the first time, rearrangements to α-arylated ketones can be performed enantioselectively using lactic acid-based iodine(III) reagents.

[Communication]
Umar Farid, Florence Malmedy, Romain Claveau, Lena Albers, Thomas Wirth
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201302358. Read article.

Doing the phosphate dance: The phospha-Wittig–Horner reaction proceeds through stepwise P-P cleavage of an oxadiphosphetane intermediate, followed by a [2,3]-sigmatropic rearrangement that paves the way for the final E2 elimination to form 1-phosphaallenes. The mechanism is thus greatly different to that of its carbon analogue, that is, the Horner–Wadsworth–Emmons reaction.

[Communication]
Anna I. Arkhypchuk, Yurii V. Svyaschenko, Andreas Orthaber, Sascha Ott
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201301469. Read article.

Designer label: A novel α-amino acid was designed as a conformationally restricted analogue of phenylalanine. It was synthesized and incorporated into the representative membrane-active peptide Magainin 2, to demonstrate its suitablility for structure analysis in oriented membranes by solid-state ¹⁹F NMR spectroscopy.

[Communication]
Anton N. Tkachenko, Dmytro S. Radchenko, Pavel K. Mykhailiuk, Sergii Afonin, Anne S. Ulrich, Igor V. Komarov
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201301344. Read article.

Put a cap on it: Hairpin-shaped RNAs and dumbbell-shaped RNAs were prepared using a thiol–maleimino Michael addition and exhibited good serum and thermal stability. These capped structures were shown to be cleaved by Dicer and RNA interference (RNAi) experiments showed that RhpRNA (see picture, top right) was highly efficient at RNAi with an IC₅₀ value of 6 pM.

[Communication]
Lv Wei, Liqiang Cao, Zhen Xi
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201301122. Read article.

Active phase of a catalyst: Using the 3D structural characterization of the environment around Mo atoms provided by X-ray absorption near-edge structure spectroscopy (left; spectrum of the Mo_K edge) and DFT calculations, the molecular-scale structure of a TiO₂-supported molybdenum oxide catalysts was defined. The structure consists of Mo octahedra arranged in a six-membered ring.

[Communication]
Asma Tougerti, Elise Berrier, Anne-Sophie Mamede, Camille La Fontaine, Valérie Briois, Yves Joly, Edmond Payen, Jean-François Paul, Sylvain Cristol
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201300538. Read article.

Shine a light: Owing to their ease of implementation and the availability of inexpensive light sources, light-induced click reactions (see picture) have become a powerful methodology for the synthesis of materials and the modification of biomaterials. Fundamental aspects of these reactions and their application in surface and materials science, as well as their potential in the study of biomolecular systems are highlighted.

[Minireview]
Mehmet Atilla Tasdelen, Yusuf Yagci
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201208741. Read article.

Gold standard: Allenamides react with aldehydes or ketones having γ, δ, or ε alkenyl groups, upon activation with suitable gold catalysts, to provide oxa-bridged systems containing seven- to nine-membered carbocycles, in a formal cascade cycloaddition. By using chiral phosphoramidite/gold or bisphosphine/gold catalysts it is possible to obtain the oxa-bridged seven- and eight-membered rings with good to high enantioselectivity.

[Communication]
Hélio Faustino, Isaac Alonso, José L. Mascareñas, Fernando López
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201302713. Read article.

No Lov lost: The cryptic thioesterase LovG was found to be responsible for product release from the lovastatin nonaketide synthase (LNKS or LovB; see scheme). LovG also helped improve the turnover of LovB through hydrolysis of incorrectly made intermediates, freeing LovB for another round of catalysis.

[Communication]
Wei Xu, Yit-Heng Chooi, Jin W. Choi, Shuang Li, John C. Vederas, Nancy A. Da Silva, Yi Tang
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201302406. Read article.

Modern-day wonders of the world: Nanostructured films of plasmonic pyramid arrays (see picture) were prepared by the simple stamping of preformed homogeneous nanocolloids. These materials show very high efficiency as optical enhancers and can be exploited for the design of quantitative, cheap, portable, and ultrasensitive optical sensors with excellent reversibility.

[Communication]
Maria Alba, Nicolas Pazos-Perez, Belén Vaz, Pilar Formentin, Moritz Tebbe, Miguel A. Correa-Duarte, Pedro Granero, Josep Ferré-Borrull, Rosana Alvarez, Josep Pallares, Andreas Fery, Angel R. de Lera, Lluis F. Marsal, Ramón A. Alvarez-Puebla
Angew. Chem. Int. Ed., May 07, 2013, DOI: 10.1002/anie.201302285. Read article.

[News]

Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201303314. Read article.

I lose track of time when I climb a mountain. My biggest motivation is to reach the summit.

[Author Profile]

Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201303078. Read article.

[Book Review]
Peer Kirsch
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201303020. Read article.

My favorite food is sashimi and Peking duck. If I were not a scientist, I would be a security guard for the National Parks of Taiwan.

[Author Profile]

Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201303136. Read article.

Light on DNA intercalators: Molecular modeling and mutasynthesis were employed to rationally tailor the antitumoral agent chartreusin into a vinyl-substituted derivative. Exposure with visible light dramatically improved antiproliferative activities owing to covalent binding with DNA and induction of apoptosis. The results hold promise for a more efficient chemotherapy, in particular for selectively treating tumors with light probes.

[Communication]
Nico Ueberschaar, Hans-Martin Dahse, Tom Bretschneider, Christian Hertweck
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302439. Read article.

The catalytic mechanism of the enzyme IspH, involved in formation of isopentenyl diphosphate and dimethylallyl diphosphate, was investigated by using HYSCORE spectroscopy combined with DFT. The results indicate the formation of an allyl anion bound to a HiPIP-like oxidized 4Fe–4S cluster, rather than formation of a cyclic, ferraoxetane intermediate, as has been proposed elsewhere.

[Communication]
Jikun Li, Ke Wang, Tatyana I. Smirnova, Rahul L. Khade, Yong Zhang, Eric Oldfield
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302343. Read article.

Irreconcilable differences: Electron-rich diacetone diperoxide is paired with the electron-deficient rings of trichloro- and tribromotrinitrobenzene to form energetic cocrystals by design. Though the two cocrystals are isostructural, the former is very stable while the later exhibits a rare metastability and favors separation.

[Communication]
Kira B. Landenberger, Onas Bolton, Adam J. Matzger
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302814. Read article.

Let’s twist again: The one-pot synthesis of a molecular Solomon link assembles four iron(II) cations, four bis(aldehyde) molecules, and four bis(amine) building blocks. The process generates two interwoven 68-membered-ring macrocycles, which feature four crossing points, in 75 % yield.

[Communication]
Jonathon E. Beves, Christopher J. Campbell, David A. Leigh, Robin G. Pritchard
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302634. Read article.

In silico veritas? Maybe not the whole truth, but very helpful suggestions and guidelines for the experimental work can be deduced from computational studies on Rh-catalyzed [3+2+1] cycloaddition reactions for the construction of cis-fused bicyclohexenones from alkylidenecyclopropanes and carbon monoxide.

[Highlight]
Indre Thiel, Marko Hapke
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302496. Read article.

More than just an empty shell: Multishelled Co₃O₄ microspheres were synthesized as anode materials for lithium-ion batteries in high yield and purity. As their porous hollow multishell structure guarantees a shorter Li⁺ diffusion length and sufficient void space to buffer the volume expansion, their rate capacity, cycling performance, and specific capacity were excellent (1615.8 mA h g⁻¹ in the 30th cycle for triple-shelled Co₃O₄; see graph).

[Communication]
Jiangyan Wang, Nailiang Yang, Hongjie Tang, Zhenghong Dong, Quan Jin, Mei Yang, David Kisailus, Huijun Zhao, Zhiyong Tang, Dan Wang
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301622. Read article.

Core assembly: The total synthesis of the myxobacterial metabolite rhizopodin, a potent actin-binding anticancer agent, has been achieved. The modular synthesis utilizes a common C1–C22 monomeric unit to assemble the dimeric 38-membered macrodiolide core, which was elaborated by a bidirectional boron-mediated aldol reaction to install the characteristic side-chains. The final global deprotection was critically dependent on the correct choice of silyl protecting groups at C16/C16'.

[Communication]
Stephen M. Dalby, Jake Goodwin-Tindall, Ian Paterson
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301978. Read article.

Surface pyroelectricity: Centrosymmetric crystals of α-glycine display an anomalous quadrupole-like pyroelectric current. This observation implies the formation of water–glycine hybrid polar layers at the (010) faces of the α-glycine crystals (see picture).

[Communication]
Silvia Piperno, Elena Mirzadeh, Eran Mishuk, David Ehre, Sidney Cohen, Miriam Eisenstein, Meir Lahav, Igor Lubomirsky
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301836. Read article.

Simple and effective exterior decorating: Single-walled carbon nanotubes were functionalized with disulfides, including cystamine-core polyamidoamine dendrimers, simply upon heating in toluene (see picture). One advantage of this method is that any unreacted disulfide can be recovered by filtration.

[Communication]
Zois Syrgiannis, Valeria La Parola, Caroline Hadad, Maribel Lucío, Ester Vázquez, Francesco Giacalone, Maurizio Prato
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301617. Read article.

Chemistry is fun because it is an assault on the senses! My favorite quote is “To strive, to seek, to find, and not to yield” from Tennyson’s poem “Ulysses”.

[Author Profile]

Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302516. Read article.

Sheltering thorium ions: A Th⁴⁺ ion supported by three neutral tetramethyl-3-oxaglutaramide ligands (L=TMOGA) is produced in the gas phase by electrospray ionization (see graph). The thorium in chiral Th(L)₃⁴⁺ is coordinated by nine oxygen atoms (see picture; O red, N blue, C gray). Quantum chemical studies revealed a decrease in Th-O binding energies and bond orders and an increase in bond lengths, as the number of coordinating ligands increases.

[Communication]
Yu Gong, Han-Shi Hu, Guoxin Tian, Linfeng Rao, Jun Li, John K. Gibson
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302212. Read article.

Ag₂CO₃ is the key: The transition-metal-catalyzed cycloaddition of isocyanides and unactivated terminal alkynes has been realized with Ag₂CO₃ as a unique and robust catalyst (see scheme). The protocol is highly efficient, allowing a broad range of terminal and internal alkynes to react under base- and ligand-free conditions, generating synthetically useful oligosubstituted pyrroles in high yields.

[Communication]
Jianquan Liu, Zhongxue Fang, Qian Zhang, Qun Liu, Xihe Bi
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302024. Read article.

The idea of receptors has fascinated scientists for more than a century. Today it is known that the G-protein coupled receptors (GPCRs) represent by far the largest, most versatile and most ubiquitous of the several families of plasma membrane receptors. The Nobel Prize for Chemistry 2012 was awarded for studies on GPCRs.

[Review]
Robert J. Lefkowitz
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301924. Read article.

Special delivery! The title system, composed of a highly magnetic core surrounded by a thin uniform gold shell, has been synthesized and applied to the magnetically facilitated delivery of genetic material (siRNA or plasmid DNA) into neural stem cells (NSCs) for controlling their neural differentiation in a spatiotemporally controlled, biocompatible manner.

[Communication]
Birju Shah, Perry T. Yin, Shraboni Ghoshal, Ki-Bum Lee
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302245. Read article.

Cells from different parts of our bodies communicate with each other using chemical messengers in the form of hormones and neurotransmitters. They process information encoded in these chemical messages using G-protein-coupled receptors (GPCRs) located in the plasma membrane. The Nobel Prize for Chemistry 2012 was awarded for studies on GPCRs.

[Review]
Brian Kobilka
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201302116. Read article.

Bringing to light: The rediscovery of visible light as an abundant energy source for organic reactions has most recently brought copper-catalyzed coupling reactions to the center of attention. This Highlight summarizes the most significant advancements in the field of C-C and C-N coupling reactions in which covalent copper–substrate complexes are photo-activated.

[Highlight]
Michal Majek, Axel Jacobi von Wangelin
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301843. Read article.

Caught in the act: A series of unique η¹-allyl palladium complexes of four-membered cyclic systems bearing β-hydrogens were prepared (see structure). Their unusual structure, reactivity, and unprecedented propensity for undergoing pericyclic reactions were uncovered.

[Communication]
Davide Audisio, Gopinadhanpillai Gopakumar, Lan-Gui Xie, Luís G. Alves, Cornelia Wirtz, Ana M. Martins, Walter Thiel, Christophe Farès, Nuno Maulide
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301034. Read article.

Striking gold: A series of variously functionalized propynyl arenes was smoothly converted into indan-2-ones by a new gold(I)-catalyzed oxidative cyclization process. [LAu]NTf₂ (Tf=trifluoromethanesulfonyl) is a superior catalyst both in terms of yield and kinetics for the present transformation.

[Communication]
Guilhem Henrion, Thomas E. J. Chavas, Xavier Le Goff, Fabien Gagosz
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301015. Read article.

'Lene' and mean: The strong Lewis acid B(C₆F₅)₃ efficiently converts some bis(arylethynyl)benzenes into dibenzopentalenes through a series of Lewis acid induced cyclization reactions at room temperature. Thus the reaction has the potential to be useful in the synthesis of substituted dibenzopentalene derivatives which are difficult to make by conventional means.

[Communication]
Chao Chen, Marcel Harhausen, René Liedtke, Kathrin Bussmann, Aiko Fukazawa, Shigehiro Yamaguchi, Jeffrey L. Petersen, Constantin G. Daniliuc, Roland Fröhlich, Gerald Kehr, Gerhard Erker
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300871. Read article.

Molecule deformation to macroactuation: In a novel hybrid assembly photoisomerization causes microscale deformation of molecules that is amplified to macroscale bending of a composite membrane. The nanoscale molecular crystals, which are unevenly distributed in a functional polymer matrix, provide a new strategy for designing higher performance actuators that combine the advantages of both molecular crystals and liquid crystal elastomers.

[Communication]
Tian Lan, Wei Chen
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300856. Read article.

I(n)organocatalysis: Neutral multidentate halogen-bond donors (halogen-based Lewis acids) catalyze the reaction of 1-chloroisochroman with ketene silyl acetals. The organocatalytic activity is linked to the presence (and number as well as orientation) of iodine substituents. As hidden acid catalysis can be ruled out with high probability, this case constitutes strong evidence for halogen-bond based organocatalysis. TBS=tert-butyldimethylsilyl.

[Communication]
Florian Kniep, Stefan H. Jungbauer, Qi Zhang, Sebastian M. Walter, Severin Schindler, Ingo Schnapperelle, Eberhardt Herdtweck, Stefan M. Huber
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301351. Read article.

Tell it where to go: Rapamycin induced the relocation of an FRB-fused protein of interest (POI) to the plasma membrane (labeled with the fusion protein GAIs–FKBP–C2(LACT)) to activate a signaling event (see picture). Subsequent treatment with a gibberellic acid ester led to the relocation of the whole GAIs–FKBP–C2(LACT)/rapamycin/FRB–POI complex to the Tom20–GID1-labeled mitochondria with the termination of POI-dependent signaling.

[Communication]
Yu-Chun Lin, Yuta Nihongaki, Tzu-Yu Liu, Shiva Razavi, Moritoshi Sato, Takanari Inoue
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301219. Read article.

Water splitting: In heterogeneous photocatalysis, it has been believed that doping transition-metal cations having partly filled d orbitals into semiconductor photocatalysts results in a significant drop in photocatalytic activity. Nevertheless, it was found that the activity for the water oxidation of BaTaO₂N could be improved by seven times upon modification by pentavalent W species (see picture).

[Communication]
Kazuhiko Maeda, Daling Lu, Kazunari Domen
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301357. Read article.

Lewis acid and oxidation catalysis are merged in the reaction discussed here, which provides access to diversely substituted N-hydroxycarbamates (see scheme). This reaction highlights the potential of nitrosoformates as electrophilic amination reagents as well as the benefits of aerobic oxidation for the formation of highly reactive species.

[Highlight]
Philipp Selig
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201301282. Read article.

Location of the carboxylate ion: A series of biaryl DMAP catalysts with an internal carboxylate was prepared, and the catalytic activities of the derivatives were evaluated to determine the carboxylate position that most accelerated the DMAP-catalyzed acylation. The carboxylate ion proximal to the pyridine ring in a face-to-face geometry was found to act as an effective general base for the acylation reaction.

[Communication]
Reiko Nishino, Takumi Furuta, Keizo Kan, Makoto Sato, Masahiro Yamanaka, Takahiro Sasamori, Norihiro Tokitoh, Takeo Kawabata
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300665. Read article.

The way is open for the physical and chemical characterization and single-crystal growth of the orthorhombic o'-In₂O₃ polymorph. Orthorhombic In₂O₃ is synthesized from rhombohedral corundum-type rh-In₂O₃ under moderately high-pressure and high-temperature conditions (8–9 GPa, 600–1100 °C) followed by recovery to ambient pressure and temperature. The crystal-structure data at ambient conditions confirm unambiguously the Rh₂O₃(II)-type structure.

[Communication]
Maged F. Bekheet, Marcus R. Schwarz, Stefan Lauterbach, Hans-Joachim Kleebe, Peter Kroll, Ralf Riedel, Aleksander Gurlo
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300644. Read article.

From six to seven: 2,2'-Di(arylethynyl)biphenyls undergo a skeletal rearrangement in the presence of a platinum(II) catalyst to afford polycyclic aromatic compounds containing an azulene unit. The reaction involves C-C bond cleavage of a benzene ring, which expands into a seven-membered ring.

[Communication]
Takanori Matsuda, Tsuyoshi Goya, Lantao Liu, Yusuke Sakurai, Shoichi Watanuki, Naoki Ishida, Masahiro Murakami
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300570. Read article.

Trigger happy: Trigger-responsive chain-shattering polymeric therapeutics (CSPTs) were prepared by condensation polymerization of a UV- or hydrogen peroxide-responsive domain and a drug as co-monomers. Drug release can be started and stopped by starting and stopping the trigger treatment. Chemotherapeutic-containing CSPTs showed trigger-responsive in vitro and in vivo antitumor efficacy.

[Communication]
Yanfeng Zhang, Qian Yin, Lichen Yin, Liang Ma, Li Tang, Jianjun Cheng
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300497. Read article.

Playing tricks on enzymes: Direct hydroxylation of benzene to phenol was catalyzed by wild-type P450BM3 in the presence of perfluorinated carboxylic acids as decoy molecules. The catalytic turnover rate reached 120 min⁻¹ per P450. The selectivity towards phenol production was very high and no overoxidation products were detected.

[Communication]
Osami Shoji, Tatsuya Kunimatsu, Norifumi Kawakami, Yoshihito Watanabe
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201300282. Read article.

Slim guests are welcome: Aromatic macrobicyclic amphiphiles underwent self-assembly through a face-to-face interaction to form dimeric micelles, which further associated laterally to form porous sheets with nanometer-sized pores. The resulting sheets efficiently intercalated planar aromatic guest molecules, whereupon the porous sheets were reversibly transformed into closed sheets (see picture).

[Communication]
Yongju Kim, Suyong Shin, Taehoon Kim, Dongseon Lee, Chaok Seok, Myongsoo Lee
Angew. Chem. Int. Ed., May 06, 2013, DOI: 10.1002/anie.201210373. Read article.

Umar Farid, Florence Malmedy, Romain Claveau, Lena Albers, Thomas Wirth*

I likes rearrangements: Hypervalent iodine compounds can be used as environmentally friendly, mild, and selective reagents for highly enantioselective rearrangements of alkenes. For the first time, rearrangements to α-arylated ketones can be performed enantioselectively using lactic acid-based iodine(III) reagents.

Published online, DOI: 10.1002/anie.201302358 – Read now

A general way is reported to synthesize novel self-supported one-dimensional mesoporous Pt nanorods with high density of mesopores by using electrochemical micelle assembly in confined space of polycarbonate membrane. The mesoporous structures with around 6–8 nm pore size and thin wall thickness are well developed over the entire area. The obtained 1D motifs show high activity and CO tolerance in the methanol oxidation reaction and also exhibit superior electrochemical activity in the oxygen reduction reaction. The all-wet approach is highly reproducible and widely applicable to other metal and alloy systems, which will be very useful for the development of future electrocatalysts.

Coming soon.

Chiral bis(diimine) ligands (derived from chiral diamines and pyridine-2-aldehyde) enantioselectively self-assemble with iron(II) sulfate to form the new enantiopure tetrahedral cage molecule ΔΔΔΔ-[Fe₄L₆] or its enantiomer, ΛΛΛΛ-[Fe₄L₆]. These versatile water-soluble capsules are capable of binding a wide range of organic guests in their large hydrophobic cavities and, additionally, are able to distinguish between the enantiomers of chiral organic guests. Furthermore, the ΔΔΔΔ-[Fe₄L₆] coordination capsule also serves as a competent supramolecular catalyst for the hydrolysis of the neurotoxic organophosphate dichlorvos.

Coming soon.

Joseph J. Richardson, Hirotaka Ejima, Samuel L. Lörcher, Kang Liang, Philipp Senn, Jiwei Cui, Frank Caruso*

Slipping into a comfortable routine: Multilayered polymer thin films were assembled on particles immobilized in agarose by electrophoresis on the basis of various interactions. Core removal then led to robust capsules with different polymer compositions (see fluorescence image). This approach enables the versatile and routine assembly of nanometer- and micron-sized capsules and coated particles with very few processing steps.

Published online, DOI: 10.1002/anie.201302092 – Read now

Christoph Sämann, Matthias A. Schade, Shigeyuki Yamada, Paul Knochel*

Highly functionalized cyclic and acyclic alkenylzinc reagents bearing functional groups such as aldehyde, keto, and ester groups were readily prepared by either direct zinc insertion in the presence of LiCl or by magnesium insertion in the presence of LiCl and ZnCl₂. Subsequent functionalization reactions like Negishi cross-couplings, acylations, and allylations were performed, furnishing polyfunctional compounds in excellent yields.

Published online, DOI: 10.1002/anie.201302058 – Read now

A chameleon luminophore: A temperature-sensing material is reported that has a high thermostability (see picture). The material is composed of color-changing luminescent coordination polymers containing Eu^III and Tb^III ions. The coordination polymer exhibits a high emission quantum yield Φ of 40 % at room temperature and a temperature-sensing ability over a wide range of 200–500 K.

[Communication]
Kohei Miyata, Yuji Konno, Takayuki Nakanishi, Atsushi Kobayashi, Masako Kato, Koji Fushimi, Yasuchika Hasegawa
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201301448. Read article.

I like refereeing because I learn a lot of new and interesting chemistry. The biggest problem that scientists face is distraction by trivial things.

[Author Profile]

Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201302592. Read article.

6 in 1: The highly enantioselective title reaction is mediated by a bifunctional catalyst and leads to E-configured vinylogous aldol products (see scheme). These products are used as common intermediates in the synthesis of six biologically active 3-hydroxy-2-oxindole derivatives (e.g., CPC-1). Computational studies indicated that the observed stereoselectivity is a result of favorable secondary π–π* and H-bonding interactions in the transition state.

[Communication]
Bo Zhu, Wen Zhang, Richmond Lee, Zhiqiang Han, Wenguo Yang, Davin Tan, Kuo-Wei Huang, Zhiyong Jiang
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201302274. Read article.

Fresh fruit not rotting vegetables: Ethylene released from fruits and vegetables accelerates their spoiling even in refrigerators. To oxidatively remove traces of ethylene from a gas mix, supported metal nanoparticles were tested. A Pt catalyst supported on mesoporous silica gave complete conversion of 50 ppm ethylene even at 0 °C. IR experiments suggest the facile oxidation of CO over Pt on the silica supports is the key to the catalytic activity.

[Communication]
Chuanxia Jiang, Kenji Hara, Atsushi Fukuoka
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201300496. Read article.

Add an O: A new strategy for preparing solution-processed organic thin-film transistors (OTFTs) is based on enhancing the surface energy of self-assembled monolayers (SAMs) by inserting polar oxygen atoms into the long alkyl chain of phosphonic acids. SAMs of these phosphonic acids on a high-k metal oxide layer lead to solution-processed n-channel OTFTs with average field effect mobilities of up to 2.5 cm² V⁻¹ s⁻¹ and low operational voltages.

[Communication]
Danqing Liu, Xiaomin Xu, Yaorong Su, Zikai He, Jianbin Xu, Qian Miao
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201300353. Read article.

Kazuhiko Maeda*, Daling Lu, Kazunari Domen*

Water splitting: In heterogeneous photocatalysis, it has been believed that doping transition-metal cations having partly filled d orbitals into semiconductor photocatalysts results in a significant drop in photocatalytic activity. Nevertheless, it was found that the activity for the water oxidation of BaTaO₂N could be improved by seven times upon modification by pentavalent W species (see picture).

Published online, DOI: 10.1002/anie.201301357 – Read now

Control confirmed: Optimization of P,N-bidentate ligands (L) reveals the importance of conformation control for intermolecular trapping of reactive α-oxo gold carbene intermediates. As a result, the highly efficient and broadly applicable synthesis of carboxymethyl ketones from readily available carboxylic acids and terminal alkynes proceeds under mild reaction conditions.

[Communication]
Kegong Ji, Yulong Zhao, Liming Zhang
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201301601. Read article.

Confined cat works better: A self-assembling heterobimetallic catalyst, comprised of a Nd/Na/amide ligand confined in an entangled multiwalled carbon nanotube (MWNT) network, outperforms the unconfined catalyst in anti-selective catalytic asymmetric nitroaldol reactions. The confined catalyst could be used repeatedly through simple filtration, and was applied to a concise enantioselective synthesis of anacetrapib.

[Communication]
Takanori Ogawa, Naoya Kumagai, Masakatsu Shibasaki
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201302236. Read article.

Prolonged periodical variations of the surface density of a film of phospholipids adsorbed on the surface of an air bubble and in contact with a dispersion of phospholipid vesicles (orange) lead to accelerated phospholipid adsorption and lowering of the interfacial tension. The phenomenon is assigned to a coupling between the periodical variation of the surface density of the phospholipid at the interface and its dilute-to-condensed (LE-to-LC) phase transition.

[Communication]
Phuc Nghia Nguyen, Gilles Waton, Thierry Vandamme, Marie Pierre Krafft
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201301974. Read article.

Autonomously folded designed β-hairpin peptides in detergent micelles show peroxidase activity with heme binding. Aromatic–aromatic cross-strand packing interactions that stabilize β-hairpin structures in solution are not strictly required for the structure and activity of a β-hairpin folded in a micelle environment.

[Communication]
Mukesh Mahajan, Surajit Bhattacharjya
Angew. Chem. Int. Ed., May 03, 2013, DOI: 10.1002/anie.201300241. Read article.

Hélio Faustino, Isaac Alonso, José L. Mascareñas*, Fernando López*

Gold standard: Allenamides react with aldehydes or ketones having γ, δ, or [epsiv] alkenyl groups, upon activation with suitable gold catalysts, to provide oxa-bridged systems containing seven- to nine-membered carbocycles, in a formal cascade cycloaddition. By using chiral phosphoramidite/gold or bisphosphine/gold catalysts it is possible to obtain the oxa-bridged seven- and eight-membered rings with good to high enantioselectivities.

Published online, DOI: 10.1002/anie.201302713 – Read now

Birju Shah, Perry T. Yin, Shraboni Ghoshal, Ki-Bum Lee*

Special delivery! The title system, composed of a highly magnetic core surrounded by a thin uniform gold shell, has been synthesized and applied to the magnetically facilitated delivery of genetic material (siRNA or plasmid DNA) into neural stem cells (NSCs) for controlling their neural differentiation in a spatiotemporally controlled, biocompatible manner.

Published online, DOI: 10.1002/anie.201302245 – Read now

Larysa Baraban, Stefan M. Harazim, Samuel Sanchez*, Oliver G. Schmidt

Chemotaxis in practice: Two different artificial catalytic micromotors (tubular and spherical, see scheme) show chemotactic behavior in microfluidic channels demonstrating that catalytic micromotors can sense the gradient of chemical fuel in their environment and be directed towards desired locations.

Published online, DOI: 10.1002/anie.201301460 – Read now No. 21/2013.

By using a neutral bidentate bis-NHC ligand (NHC=1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene), an unprecedented bis-carbene chlorosilyliumylidene complex could be isolated, in which both HOMO and LUMO are mainly represented on the silicon(II) atom according to DFT calculations. Remarkably, dechlorination of the latter complex by sodium naphthalenide led to the first isolable cyclic siladicarbene with a bent geometry (C–Si–C angle: 89.1°) and average Si–C distances of 1.869 Å. According to the DFT calculations, the latter compound bears a single Si(0) atom with strikingly high basicity as predicted by the calculated first and second proton affinities and is hence best described as a silylone.

Coming soon.

Just click with silver: Pyrroles are prepared by the co-cyclization of terminal alkynes and isocyanides in a silver-catalyzed click reaction. This protocol represents an extremely simple, efficient, and atom-economic approach to substituted pyrroles in good yields with high selectivity, thus complementing the click method for the rapid formation of multifunctional heterocycles.

[Communication]
Meng Gao, Chuan He, Hongyi Chen, Ruopeng Bai, Ben Cheng, Aiwen Lei
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302604. Read article.

An overwhelming response: The exposure of a supramolecular hydrogel based on a diselenide-containing polymer and a peptide amphiphile containing a drug moiety to γ radiation led to a gel–sol transition owing to the oxidative cleavage of diselenide bonds in the polymer main chain (see picture). The hydrogel can also act as a UV-mediated drug self-delivery system and suggests a new avenue for combined radio- and chemotherapy.

[Communication]
Wei Cao, Xiaoli Zhang, Xiaoming Miao, Zhimou Yang, Huaping Xu
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201300662. Read article.

Tiny pores: Benzodifuran moieties were introduced into microporous organic networks (MONs) through a tandem process consisting of Sonogashira coupling of 1,3,5-triethynylbenzene and 2,5-diiodo-1,4-hydroquinone and intramolecular cyclization. The resultant benzodifuran-containing MON showed promising photocatalytic activities in the oxidative conversion of primary amines into imines.

[Communication]
Narae Kang, Ji Hoon Park, Kyoung Chul Ko, Jiseul Chun, Eunchul Kim, Hee-Won Shin, Sang Moon Lee, Hae Jin Kim, Tae Kyu Ahn, Jin Yong Lee, Seung Uk Son
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201300655. Read article.

[Correspondence]
David Danovich, Sason Shaik, Henry S. Rzepa, Roald Hoffmann
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302350. Read article.

It only takes one mutation: A strategically placed single mutation in a non-enzymatic protein scaffold produced AlleyCat, a small, allosterically regulated catalyst of Kemp elimination. In only seven rounds of directed evolution the enzymatic efficiency of the original 74 amino acid residue catalyst was improved more than 220-fold to achieve a k_cat value higher than that of catalytic antibodies for the same reaction, still preserving allosteric regulation.

[Communication]
Olesia V. Moroz, Yurii S. Moroz, Yibing Wu, Alissa B. Olsen, Hong Cheng, Korrie L. Mack, Jaclyn M. McLaughlin, Elizabeth A. Raymond, Krystyna Zhezherya, Heinrich Roder, Ivan V. Korendovych
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302339. Read article.

The influence of the reaction rate at the SECM tip on the overall imaging result is often neglected during respiration studies performed by SECM. The effect of the driving force of the tip reaction is elucidated using a potential pulse profile implemented into a constant-distance mode. Time-dependent data acquisition allows visualization of the transition between a tip behaving as a passive observer and a tip actively inducing transmembrane diffusion of oxygen.

[Communication]
Michaela Nebel, Stefanie Grützke, Nizam Diab, Albert Schulte, Wolfgang Schuhmann
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301098. Read article.

It’s elemental! β-Rhombohedral boron was investigated as an elemental photocatalyst. Boron crystals were found to be photocatalytically active in the generation of ^.OH radicals under irradiation with visible light (see picture); however, the presence of an amorphous oxide layer on the surface of the crystals impaired their photocatalytic activity.

[Communication]
Gang Liu, Li-Chang Yin, Ping Niu, Wei Jiao, Hui-Ming Cheng
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302238. Read article.

Smaller can be better: The first example of meta-quinodimethane embedded in an indenofluorene framework has been synthesized. 10,12-Dimesitylindeno[2,1-b]fluorene exhibits extremely low-energy light absorption, despite the small conjugation space of the molecule, which consists of only 20 π electrons.

[Communication]
Akihiro Shimizu, Ryohei Kishi, Masayoshi Nakano, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Ichiro Hisaki, Mikiji Miyata, Yoshito Tobe
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302091. Read article.

A useful handle: One major limitation of protein semi-synthesis is the need for Cys at the ligation site in native chemical ligation reactions. It is shown that a transferase enzyme can deliver homocysteine to the N-terminus of an expressed protein (see scheme). Homocysteine can be used in a ligation reaction and then converted to Met. This allows one to use the MetArg or MetLys motif as a point of disconnection in semi-synthesis.

[Communication]
Tomohiro Tanaka, Anne M. Wagner, John B. Warner, Yanxin J. Wang, E. James Petersson
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201302065. Read article.

The aromatic low-valent lead analogue of an indenyl anion (see scheme; 1) undergoes oxidation with SnCl₂ to form the base-stabilized lead(I) dimer 2. Reduction of 2 with lithium regenerates 1. These compounds were characterized by NMR spectroscopy and X-ray crystallography.

[Communication]
Siew-Peng Chia, Hong-Wei Xi, Yongxin Li, Kok Hwa Lim, Cheuk-Wai So
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301954. Read article.

Ion nanowire: Electron transport through discrete gold-ion arrays within coordination cages was directly measured between Au nanogap electrodes (see picture) using STM. Precise calibration of the electron transport distance demonstrates that Au-ion arrays exhibit good conductance and only moderate loss with increasing transport length.

[Communication]
Manabu Kiguchi, Junichi Inatomi, Yuuta Takahashi, Ryota Tanaka, Takafumi Osuga, Takashi Murase, Makoto Fujita, Tomofumi Tada, Satoshi Watanabe
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301665. Read article.

First things first: The title reaction of arenes bearing ortho-directing groups (DG) in the presence of a ruthenium catalyst and aryl iodide is presented. The reaction is general for variously substituted aryl iodides to give ketones in moderate to good yields, and water serves as the solvent. The system is highly selective towards the mono-carbonylative arylation by ortho C-H functionalization. cod=cyclo-1,5-octadiene.

[Communication]
Anis Tlili, Johannes Schranck, Jola Pospech, Helfried Neumann, Matthias Beller
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301663. Read article.

“Fisching” for complexity: The chiral Brønsted acid (R)-STRIP catalyzes the asymmetric Fischer indolization of a range of monosubstituted cyclopentanones and cyclohexanones to give chiral fused indolines bearing a quaternary stereogenic center at the 3-position. The method has been extended to include substrates bearing a tethered nucleophile, thus allowing for enantioselective indolization/ring-closing cascades to complex propellanes featuring two vicinal quaternary stereocenters.

[Communication]
Alberto Martínez, Matthew J. Webber, Steffen Müller, Benjamin List
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301618. Read article.

Amazing diazo: The title reaction leads to highly functionalized diazo compounds in good yields with excellent enantioselectivities (see scheme; Boc=tert-butoxycarbonyl). The utility of the products was demonstrated by the rapid synthesis of a number of optically pure nitrogen heterocycles. The key to this process was the use of 2,2,2-trifluoroethyl diazoacetate as a superior nucleophilic reagent.

[Communication]
Haibin Mao, Aijun Lin, Yan Shi, Zhijie Mao, Xuebin Zhu, Weipeng Li, Hongwen Hu, Yixiang Cheng, Chengjian Zhu
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301509. Read article.

[Correspondence]
Gernot Frenking, Markus Hermann
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301485. Read article.

It takes two different functional additives to produce the title structures. The proposed mechanism based on the nonclassical particle-mediated crystallization of calcium carbonate demonstrates the individual and cooperative effects of the polymer poly(sodium 4-styrenesulfonate) and small folic acid molecules on the formation of heterostructures at different reaction stages.

[Communication]
Sha-Sha Wang, Andreas Picker, Helmut Cölfen, An-Wu Xu
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201301184. Read article.

An siRNA conjugate is based on an acid-labile maleic acid amide linkage for programmed transfer of siRNA from the endosome to the cytosol and siRNA release in the cell interior. The procedure relies on reversible stability in response to endosomal acidic pH value. The complexed polyionic conjugate achieved gene silencing in cultured cancerous cells with negligible side effects.

[Communication]
Hiroyasu Takemoto, Kanjiro Miyata, Shota Hattori, Takehiko Ishii, Tomoya Suma, Satoshi Uchida, Nobuhiro Nishiyama, Kazunori Kataoka
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201300178. Read article.

The routine calculation of EI mass spectra is based on a combination of fast quantum chemical methods, molecular dynamics, and the stochastic preparation of “hot” primary ions. All basic elementary processes are considered with minor empiricism and realistic potential free energy surfaces are employed. Reasonable spectra are generated along with detailed information on the corresponding decomposition and reaction mechanisms.

[Communication]
Stefan Grimme
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201300158. Read article.

Focus on chemical transitions: Epoxidation of a double bond in conjugation to a fluorescent dye was studied at single-molecule level. Direct observation of oxirane formation, indicated as a spectral shift from substrate to product state, revealed an alternative reaction pathway for the epoxidation reaction.

[Communication]
Arina Rybina, Carolin Lang, Marcel Wirtz, Kristin Grußmayer, Anton Kurz, Frank Maier, Alexander Schmitt, Oliver Trapp, Gregor Jung, Dirk-Peter Herten
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201300100. Read article.

Distance matters: Interpretation of infrared spectra regularly involves the assignment of absorption bands to certain functional groups of the molecule. Distance-dependent vibrational energy transfer can be used for exact band assignment in molecules in which assignment is difficult and quantum chemical computations are contradictory.

[Communication]
Henrike M. Müller-Werkmeister, Yun-Liang Li, Eliza-Beth W. Lerch, Damien Bigourd, Jens Bredenbeck
Angew. Chem. Int. Ed., Apr 29, 2013, DOI: 10.1002/anie.201209916. Read article.

Hyungki Kim, Yoonkook Son, Chibeom Park, Jaephil Cho*, Hee Cheul Choi*

Direct growth of a single to a few layers of graphene on a germanium nanowire (Gr/Ge NW; see picture) was achieved by a metal-catalyst-free chemical vapor deposition (CVD) process. The Gr/Ge NW was used as anode in a lithium ion battery. This material has a specific capacity of 1059 mA h g⁻¹ at 4.0 C, a long cycle life over 200 cycles, and a high capacity retention of 90 %.

Published online, DOI: 10.1002/anie.201300896 – Read now

The reaction of enyne 1 with a 1:1 mixture of [LAuCl] and AgSbF₆ in CD₂Cl₂ at −20 °C gave the gold complex 2 in 97 % yield (NMR spectroscopy). Warming a solution of 2 at 25 °C led to 1,3-H migration (t_1/2≈16 min) to form the gold complex 3 with 96 % selectivity. ¹³C NMR analysis of 2 and 3 showed predominant metallacyclopropane character of the gold-bicyclo[3.2.0]heptene bond.

[Communication]
Rachel E. M. Brooner, Timothy J. Brown, Ross A. Widenhoefer
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201301640. Read article.

Expanding the genetic code opens new avenues to modulate protein function in real time. By genetically incorporating photoreactive phenyl azide, the fluorescent properties of green fluorescent protein (GFP) can be modulated by light. Depending on the residue in GFP programmed to incorporate the phenyl azide, different effects on function and photochemical pathways are observed.

[Communication]
Samuel C. Reddington, Pierre J. Rizkallah, Peter D. Watson, Rachel Pearson, Eric M. Tippmann, D. Dafydd Jones
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201301490. Read article.

Methane scrabble: To have the right elements is sometimes just not sufficient, as shown by [M(OH)]⁺ (M=Ti, V), which do not react with methane. However, reshuffling of the “tiles” to [HMO]⁺ changes the reactions behavior completely, leading to the first example of C-H bond activation of methane by an early first-row transition-metal cation.

[Communication]
Robert Kretschmer, Maria Schlangen, Helmut Schwarz
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201300900. Read article.

Polysubstituted 5- and 6-membered carbocycles were synthesized by the title reaction. The one-pot dynamic relay process generates four new stereocenters, including a quaternary carbon center, in a highly enantioselective fashion (99.5:0.5→99:0.5 e.r.) by using a simple combination of palladium and chiral amine co-catalysts.

[Communication]
Guangning Ma, Samson Afewerki, Luca Deiana, Carlos Palo-Nieto, Leifeng Liu, Junliang Sun, Ismail Ibrahem, Armando Córdova
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201300559. Read article.

A new cycloadduct: The title reaction of methylene-trimethylenemethane (TMM) with α,β-unsaturated N-acyl pyrroles is an efficient method for the construction of vinylidenecyclopentanes. A asymmetric protocol using this unique donor forms cycloadducts in excellent yield and enantioselectivity, making use of a bisdiamidophosphite ligand derived from trans-1,2-stilbenediamine.

[Communication]
Barry M. Trost, Autumn Maruniak
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201300275. Read article.

Complex heterocyclic products were synthesized from simple alkynamine and alkynol derivatives in a double cycloisomerization/heterodimerization cascade reaction (see scheme). The reaction includes the heterocoupling reaction of two different electron-rich alkenes and leads to the formation of four new bonds and three stereocenters (two of them quaternary).

[Communication]
Alicia Galván, Jonás Calleja, Francisco J. Fañanás, Félix Rodríguez
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201209870. Read article.

Kitset hollow spheres: The combination of twin polymerization with hard templates makes hollow carbon spheres (HCSs) with tailored properties easily accessible. The thickness and pore texture of the HCS shells and also the diameter of the spherical cavity can be varied. The application potential of synthesized HCS is substantiated by an excellent cycling stability of lithium–sulfur batteries.

[Communication]
Falko Böttger-Hiller, Patrick Kempe, Gerhard Cox, Alexander Panchenko, Nicole Janssen, Albrecht Petzold, Thomas Thurn-Albrecht, Lars Borchardt, Marcus Rose, Stefan Kaskel, Colin Georgi, Heinrich Lang, Stefan Spange
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201209849. Read article.

9-Helix: 4-Amino(methyl)-1,3-thiazole-5-carboxylic acids (ATCs) were synthesized as new γ-amino acid building blocks. The structures of various ATC oligomers were analyzed in solution by CD and NMR spectroscopy and in the solid state by X-ray crystallography. The ATC sequences adopted a well-defined 9-helix structure in the solid state and in aprotic and protic organic solvents as well as in aqueous solution.

[Communication]
Loïc Mathieu, Baptiste Legrand, Cheng Deng, Lubomir Vezenkov, Emmanuel Wenger, Claude Didierjean, Muriel Amblard, Marie-Christine Averlant-Petit, Nicolas Masurier, Vincent Lisowski, Jean Martinez, Ludovic T. Maillard
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201302106. Read article.

Spectroscopic fingerprint: Infrared–ultraviolet double resonance photodissociation is used for conformational assignment of the electronic spectra of a cold protonated decapeptide (see picture). A mechanism of the IR–UV depletion spectroscopy is proposed and a procedure of using it for measurements of absolute absorption cross-sections of vibrational transitions is elaborated.

[Communication]
Natalia S. Nagornova, Thomas R. Rizzo, Oleg V. Boyarkin
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201301656. Read article.

Seamless observation: Magnetic measurements in a solid-state electrochemical environment have been developed and applied to a mixed-valent chromium Prussian blue analogue (PBA) ferrimagnet. Battery cells containing PBA as a cathode active material were inserted into a SQUID and the PBA reduction during battery discharge was controlled. Magnetic changes were revealed that can be understood by the redox-induced spin changes of the Cr ions.

[Communication]
Tetsuya Yamada, Kantaro Morita, Heng Wang, Keita Kume, Hirofumi Yoshikawa, Kunio Awaga
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201301084. Read article.

Just add water! The title reaction is catalyzed by an acridine-based pincer complex (1, see scheme). This one-step transformation uses water as the only reagent in the absence of additional bases, oxidants, or reductants. Cyclization of 1,4-diaminobutane and 1,6-diaminohexane catalyzed by 1 leads to the formation of pyrrolidine and azepane, respectively.

[Communication]
Julia R. Khusnutdinova, Yehoshoa Ben-David, David Milstein
Angew. Chem. Int. Ed., Apr 25, 2013, DOI: 10.1002/anie.201301000. Read article.

Adel M. ElSohly, Daniel A. Wespe, Tyler J. Poore, Scott A. Snyder*

Folding it all together: Most of the syntheses developed for the securinega alkaloid class require lengthy sequences to create their bridging butenolide domains. A novel approach uses
N-heterocyclic carbenes (NHCs) and Lewis acids to forge the entire domain in a single step from appropriate precursors, showing that ynal-derived homoenolates can participate as nucleophiles in intramolecular settings (see scheme).

Published online, DOI: 10.1002/anie.201301849 – Read now No. 22/2013.

Strongly emissive gold(III) complexes which display phosphorescence in the visible region and with emission quantum yields and lifetimes up to 58% and 305 µs, respectively, could be achieved using chelating cyclometalated ligands having fluorene substituent(s). These gold(III) complexes can sensitize energy up-conversion with a quantum yield Φ_UC up to 9.8% and display rich two-photon absorption properties.

Received February 08, 2013, published online May 16, 2013, DOI: 10.1002/anie.201301149 – read now.

Did you read this article? Was it important to you? Let us know...

A method based on plasmon resonance Rayleigh scattering (PRRS) spectroscopy and dark-field microscopy (DFM) was established for the real-time monitoring of a click reaction at the single-nanoparticle level. Click reactions on the surface of single gold nanoparticles (GNPs) result in interparticle coupling, which leads to a red-shift of the λ_max (Δλ_max=43 nm) in the PRRS spectra and a color change of the single gold nanoparticles in DFM (from green to orange).

[Communication]
Lei Shi, Chao Jing, Wei Ma, Da-Wei Li, Jonathan E. Halls, Frank Marken, Yi-Tao Long
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301930. Read article.

Silver screen: The title reaction provides a convenient and efficient method for the construction of 5-substituted 3-trifluoromethylpyrazoles under mild reaction conditions. By using this protocol, the marketed drug Celecoxib (antiarthritic) could be easily synthesized (see scheme; DMF=N,N-dimethylformamide).

[Communication]
Feng Li, Jing Nie, Long Sun, Yan Zheng, Jun-An Ma
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301870. Read article.

About phase: The coexistence of rhombohedral LiTMO₂ (TM=Ni, Co, or Mn) and monoclinic Li₂MnO₃-like structures inside Li_1.2Mn_0.567Ni_0.166Co_0.067O₂ is revealed directly at atomic resolution. The hetero-interface along the [001]_rh/[103]_mon zone axis direction is demonstrated, indicating the two-phase nature of these lithium-rich cathode materials (green Li, blue Mn, red O, cyan TM).

[Communication]
Haijun Yu, Ryo Ishikawa, Yeong-Gi So, Naoya Shibata, Tetsuichi Kudo, Haoshen Zhou, Yuichi Ikuhara
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301236. Read article.

Give it a tweak: A novel oxidizing directing group was developed for a rhodium(III)-catalyzed C-H functionalization of N-phenoxyacetamides with alkynes. A small change in the reaction conditions leads to either ortho-hydroxyphenyl-substituted enamides or cyclization to deliver benzofurans with high selectivity (see scheme; Cp*=C₅Me₅).

[Communication]
Guixia Liu, Yangyang Shen, Zhi Zhou, Xiyan Lu
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300881. Read article.

An orientational change from homeotropic to planar of liquid crystal (LC) mesogens and the microphase separation (MPS) domains is attained by the segregated skin layer at the free surface. This allows for an efficient in-plane photoalignment of the cylindrical domains. The surface segregation strategy is very simple and is therefore expected to open up new possibilities for the orientation control of various types of LC materials.

[Communication]
Kei Fukuhara, Yasuyoshi Fujii, Yuki Nagashima, Mitsuo Hara, Shusaku Nagano, Takahiro Seki
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300560. Read article.

The apparent and the real: What looks like a Friedel–Crafts alkylation reaction of electron-deficient pyrroles is actually a Pd^II-catalyzed, norbornene-mediated C-H activation reaction, in which the alkylation of the pyrrole core occurs by reductive elimination. As well as ethyl-1H-pyrrole-2-carboxylate (see scheme), several other 2,3-disubstituted pyrroles underwent the selective C5 alkylation in good yield.

[Communication]
Lei Jiao, Thorsten Bach
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301154. Read article.

An efficient protocol for the selective fluorination of benzylic C-H bonds is described. The process is catalyzed by manganese salen complexes and uses nucleophilic fluorine sources, such as triethylamine trihydrofluoride and KF. Reaction rates are sufficiently high (30 min) to allow adoption for the incorporation of ¹⁸F fluoride sources for PET imaging applications.

[Communication]
Wei Liu, John T. Groves
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301097. Read article.

Reinventing the wheel: Bimetallic AuPd nanowheels (see picture), a freestanding form of 2D AuPd nanostructures, were synthesized in a one-pot process. The well-defined and tunable surface plasmon resonance displayed by these nanowheels was exploited in a unique catalytic process in which light energy was used to drive catalytic reactions, such as the Suzuki coupling, with much higher efficiency than that of the conventional heating process.

[Communication]
Xiaoqing Huang, Yongjia Li, Yu Chen, Hailong Zhou, Xiangfeng Duan, Yu Huang
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301096. Read article.

Tandem: Allylic alcohols react with N-chlorosuccinimide (NCS) in a tandem 1,3-H shift/C-Cl bond formation leading to α-chloroketones and α-chloroaldehydes. The reactions proceed with complete selectivity to give single constitutional isomers of monochlorinated carbonyl compounds. The utility of the transformation is illustrated by the straightforward synthesis of 4,5-disubstituted 2-aminothiazoles from allylic alcohols.

[Communication]
Nanna Ahlsten, Antonio Bermejo Gómez, Belén Martín-Matute
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301013. Read article.

Direct growth of a single to a few layers of graphene on a germanium nanowire (Gr/Ge NW; see picture) was achieved by a metal-catalyst-free chemical vapor deposition (CVD) process. The Gr/Ge NW was used as anode in a lithium ion battery. This material has a specific capacity of 1059 mA h g⁻¹ at 4.0 C, a long cycle life over 200 cycles, and a high capacity retention of 90 %.

[Communication]
Hyungki Kim, Yoonkook Son, Chibeom Park, Jaephil Cho, Hee Cheul Choi
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300896. Read article.

Stars that shine bright: A high local dye concentration in doped silica-based core–shell nanoparticles causes self-quenching and spectral broadening (top images). This phenomenon jeopardizes the potential advantages of heavily doped systems. Förster resonance energy transfer (FRET) to an acceptor co-included in the silica led to ultrabright nanoparticles (bottom images) with a preselected narrow-band emission and a pseudo-Stokes shift of 129 nm.

[Communication]
Damiano Genovese, Sara Bonacchi, Riccardo Juris, Marco Montalti, Luca Prodi, Enrico Rampazzo, Nelsi Zaccheroni
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301155. Read article.

Putting osmium in its place: The immobilization of hazardous OsO₄ on polymer nanobrushes in a microreactor is a safe, effective, and green concept. The method allows reactions to be performed in a time- and chemical-saving manner, with little environmental impact, as compared to spill-over bulk processes.

[Communication]
K. C. Basavaraju, Siddharth Sharma, Ram Awatar Maurya, Dong-Pyo Kim
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301124. Read article.

Parallel-stacked gold nanowires (NWs) in a ring conformation are induced to coalesce, forming solid seamless rings. The axial lattice orientation of the original Au NWs is preserved in the coalesced rings (see picture; scale bars 2 nm, insets 50 nm). A zipper mechanism is proposed to reconcile the three major events in coalescing nanocrystals: ligand loss, lattice alignment, and coalescence.

[Communication]
Jun Xu, Yawen Wang, Xiaoying Qi, Cuicui Liu, Jiating He, Hua Zhang, Hongyu Chen
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201301271. Read article.

Elastic sensors: A simple method is presented for the measurement of specific biomolecular interactions with soft colloidal hydrogel particles (SCPs) as sensors. Carbohydrate/lectin interactions (see picture; green: carbohydrate molecules) were studied by optical detection of the mechanical deformation of the particles on a lectin surface. The affinity of various carbohydrate inhibitors could also be readily determined.

[Communication]
Daniel Pussak, Daniela Ponader, Simone Mosca, Salomé Vargas Ruiz, Laura Hartmann, Stephan Schmidt
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300469. Read article.

The T-helper epitope peptide P30 (green in the scheme) from tetanus toxoid was used as the immunostimulant in MUC1 glycopeptide antitumor vaccines and apparently also acts as a built-in adjuvant. P30-conjugated glycopeptide vaccines containing three glycans in the immunodominant motifs PDTRP and GSTAP induced much stronger immune responses and complement dependent cytotoxicity mediated killing of tumor cells when applied in plain PBS solution without complete Freund’s adjuvant.

[Communication]
Hui Cai, Mei-Sha Chen, Zhan-Yi Sun, Yu-Fen Zhao, Horst Kunz, Yan-Mei Li
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300390. Read article.

Fluid catalytic cracking (FCC) is the main conversion process used in oil refineries. An X-ray microscopy method is used to show that metal poisoning and related structural changes in the zeolite active material lead to a non-uniform core–shell deactivation of FCC catalyst particles. The study links the detrimental effect of V and Ni poisoning with zeolite destruction and dealumination in a spatial manner within a single FCC catalyst particle.

[Communication]
Javier Ruiz-Martínez, Andrew M. Beale, Upakul Deka, Mathew G. O'Brien, Paul D. Quinn, J. Fred W. Mosselmans, Bert M. Weckhuysen
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201210030. Read article.

The controversy over the absolute configuration of (+)-erythro-mefloquine, the less psychosis-causing enantiomer of the anti-malarial drug Lariam, has been resolved by Mosher ester crystallization. The configuration determined previously by physical methods (see scheme) is correct, while the configuration determined by three enantioselective syntheses is wrong.

[Communication]
Michael Müller, Claudia M. Orben, Nina Schützenmeister, Manuel Schmidt, Andrei Leonov, Uwe M. Reinscheid, Birger Dittrich, Christian Griesinger
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300258. Read article.

Amine meets arene: A method for direct amination of β-C(sp²)-H bonds of benzoic acid derivatives and γ-C(sp²)-H bonds of benzylamine derivatives has been developed. The reaction is catalyzed by Cu(OAc)₂ and a Ag₂CO₃ cocatalyst, and shows high generality and functional-group tolerance, as well as providing a straightforward means for the preparation of ortho-aminobenzoic acid derivatives.

[Communication]
Ly Dieu Tran, James Roane, Olafs Daugulis
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201300135. Read article.

Experimental and theoretical charge density studies and molecular orbital analyses suggest that the complexes [Cp₂Ti(PMe₃)SiH₂Ph₂] (1) and [Cp₂Ti(PMe₃)SiHCl₃] (2) display virtually the same electronic structures. No evidence for a significant interligand hypervalent interaction could be identified for 2. A bonding concept for transition-metal hydrosilane complexes aims to identify the true key parameters for a selective activation of the individual M-Si and Si-H bonds.

[Communication]
Wolfgang Scherer, Petra Meixner, José Enrique Barquera-Lozada, Christoph Hauf, Andreas Obenhuber, Andreas Brück, David J. Wolstenholme, Klaus Ruhland, Dirk Leusser, Dietmar Stalke
Angew. Chem. Int. Ed., Apr 24, 2013, DOI: 10.1002/anie.201210224. Read article.

Yoshitsune Sugano, Yasuhiro Shiraishi*, Daijiro Tsukamoto, Satoshi Ichikawa, Shunsuke Tanaka, Takayuki Hirai

Rejuvenating sunlight: Supported Au–Cu bimetallic alloy nanoparticles promote aerobic oxidation at room temperature under visible light ([lambda]>450 nm) irradiation with little deactivation by the oxidation of surface Cu atoms by oxygen. This is achieved through the reduction of oxidized surface Cu atoms by the surface Au atoms, a process which is activated by visible-light irradiation, even by sunlight.

Published online, DOI: 10.1002/anie.201301669 – Read now No. 20/2013.

The pyridine heterocycle is an important structural motif that can be found in many natural products, drugs, herbicides, and fungicides. Here, a sustainable iridium-catalyzed pyridine synthesis is introduced. Alcohols and γ-amino alcohols are deoxygenated and selectively linked through C–N and C–C bond formation steps. The starting materials can be obtained from renewable resources. Three equivalents of hydrogen gas are eliminated in the course of the reaction. The synthesis protocol tolerates a large variety of functional groups and significantly extents the scope of existing pyridine syntheses. The new chemistry is not just sustainable it also can be impressive in scope.

Coming soon.

Coming soon.

See the list now.

Wei Liu, John T. Groves*

An efficient protocol for the selective fluorination of benzylic C–H bonds is described. The process is catalyzed by manganese salen complexes and uses nucleophilic fluorine sources, such as triethylamine trihydrofluoride and KF. Reaction rates are sufficiently high (30 min) to allow adoption for the incorporation of ¹⁸F fluoride sources for PET imaging applications.

Published online, DOI: 10.1002/anie.201301097 – Read now

An interesting feature of (6–4) photoproducts is their relatively long-wavelength absorption, which could extend the active fraction of sunlight. Surprisingly, their potential role as intrinsic DNA photosensitizers has not been addressed yet. This appealing question has been tackled here by model studies with a 5-methyl-2-pyrimidone deoxyribonucleoside, the main chromophore of (6–4) photoproducts. The results reveal photosensitized formation of oxidation products and cyclobutane thymine dimers. Overall, this raises the issue of a possible aggravation of the photomutagenicity of (6–4) lesions, acting as Trojan horses.

Received March 14, 2013, published online May 09, 2013, DOI: 10.1002/anie.201302176 – read now.

Did you read this article? Was it important to you? Let us know...

A general approach toward the asymmetric total synthesis of various aspidosperma alkaloids includes the combination of a C-H bond activation with a Heck-type coupling, and the stereo-controlled formation of piperidine and pyrrolidine rings as key steps. The feasibility of this approach was demonstrated with the total synthesis of aspidophytine in 18 steps from 4,4-disubstituted cyclohexanedione and 2,3-dimethoxyaniline (see scheme).

[Communication]
Rongwen Yang, Fayang G. Qiu
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201302442. Read article.

High-tech pH paper: A “chameleon” pH probe composed of rhodamine (red, see scheme) and fluorescein (green) units emits at wavelengths of 580 nm and 512 nm, where the intensities show a contrary response to pH changes. Confocal microscopy of HeLa cells with this probe reveals red and green spots; the ratio of these signals can be calibrated to give the pH value of the respective organelle.

[Communication]
Min Hee Lee, Ji Hye Han, Jae Hong Lee, Nayoung Park, Rajesh Kumar, Chulhun Kang, Jong Seung Kim
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301894. Read article.

Orchestrated yet nonconsonant: The challenge posed by the “umpoled” 1,4-dioxygenation pattern characteristic for the polyketide frame of amphidinolide F was mastered by a late-stage ring-closing alkyne metathesis followed by a directed transannular hydration under the aegis of a carbophilic π-acid catalyst. This concordant strategy enabled a concise total synthesis of this enticing marine natural product.

[Communication]
Gaëlle Valot, Christopher S. Regens, Daniel P. O'Malley, Edouard Godineau, Hiroshi Takikawa, Alois Fürstner
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301700. Read article.

A 100 % atom-efficient synthesis of ketones from electron-deficient internal olefins was achieved using O₂ as a “green” oxidant (see scheme, DMA=N,N-dimethylacetamide, EWG=electron-withdrawing group). Various electron-deficient olefins were oxidized to the corresponding ketones with over 99 % selectivity and without the formation of olefin isomers or their oxidized products.

[Communication]
Takato Mitsudome, Syuhei Yoshida, Tomoo Mizugaki, Koichiro Jitsukawa, Kiyotomi Kaneda
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301611. Read article.

My motto is “simple things first”. My favorite composer is Johann Sebastian Bach.

[Author Profile]

Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201302473. Read article.

Silicon swallows up boron: The novel open tetrahedral framework structure (OTF) of the Zintl phase LiBSi₂ was made by applying high pressure to a mixture of LiB and elemental silicon. The compound represents a new topology in the B-Si net (called tum), which hosts Li atoms in the channels (see picture). LiBSi₂ is the first example where B and Si atoms form an ordered common framework structure with B engaged exclusively in heteronuclear B-Si contacts.

[Communication]
Michael Zeilinger, Leo van Wüllen, Daryn Benson, Verina F. Kranak, Sumit Konar, Thomas F. Fässler, Ulrich Häussermann
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301540. Read article.

Spiral binding: A highly enantioselective hydrogenation of unsaturated heterocyclic acids has been developed by using chiral iridium/spirophosphino oxazoline catalysts (see scheme; BAr_F⁻=tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, Boc=tert-butoxycarbonyl). This reaction provided an efficient method for the preparation of optically active heterocyclic acids with excellent enantioselectivities.

[Communication]
Song Song, Shou-Fei Zhu, Liu-Yang Pu, Qi-Lin Zhou
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301341. Read article.

A simple and straightforward method for the stereocontrolled synthesis of β-linked N-glycosides uses alkyl and aryl azides as the nitrogen source. The N-glycosides are formed in high yields and with high β selectivities (typically >70 % yield, >15:1 β:α selectivity). This approach is also amenable to the synthesis of N-glycosylated amino acids and peptides (see example, Fmoc=9-fluorenylmethoxycarbonyl).

[Communication]
Jianbin Zheng, Kaveri Balan Urkalan, Seth B. Herzon
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201301264. Read article.

Nanoscale total synthesis: Diverse nanoparticle reaction libraries can be applied sequentially and predictably to construct complex multicomponent nanoscale architectures, in analogy to the total synthesis concept used to construct large and complex molecules.

[Review]
Matthew R. Buck, Raymond E. Schaak
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201207240. Read article.

An aptamer-based strategy was developed for the high-throughput analysis of protein biomarkers, such as lysozyme, by on-target MALDI-TOF MS. The aptamers were immobilized on the target plate through formation of covalent bonds with a stable and porous gold layer. An infrared laser was subsequently applied for fast proteolysis (see picture). High sensitivities were observed both in standard solutions and human urine.

[Communication]
Xueyang Zhang, Shaochun Zhu, Ya Xiong, Chunhui Deng, Xiangmin Zhang
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201300566. Read article.

Getting to the point: Tip-enhanced Raman spectroscopy (TERS) combines the chemical information of Raman spectroscopy experiments with a high signal enhancement and high spatial resolution. The current status of the technique is described together with the shortcomings and pitfalls that have to be considered for spectroscopic imaging by TERS.

[Review]
Thomas Schmid, Lothar Opilik, Carolin Blum, Renato Zenobi
Angew. Chem. Int. Ed., Apr 22, 2013, DOI: 10.1002/anie.201203849. Read article.

Julia R. Khusnutdinova, Yehoshoa Ben-David, David Milstein*

Just add water! The title reaction is catalyzed by an acridine-based pincer complex (1, see scheme). This one-step transformation uses water as the only reagent in the absence of additional bases, oxidants, or reductants. Cyclization of 1,4-diaminobutane and 1,6-diaminohexane catalyzed by 1 leads to the formation of pyrrolidine and azepane, respectively.

Published online, DOI: 10.1002/anie.201301000 – Read now

Masashi Hayashi, Masahide Sano, Yasuhiro Funahashi, Shuichi Nakamura*

Managing the Mannich: The first enantioselective vinylogous Mannich reaction of siloxyfurans with ketimines derived from unactivated ketones has been developed. Excellent yields and enantioselectivities were obtained using a new class of readily accessible cinchona alkaloid amide/Cu(OAc)₂ catalysts on a range of substrates.

Published online, DOI: 10.1002/anie.201301917 – Read now No. 21/2013.

Muhammad K. Kashif, Michael Nippe, Noel. W. Duffy, Craig M. Forsyth, Christopher J. Chang*, Jeffrey R. Long*, Leone Spiccia*, Udo Bach*

Energy conversion: A cobalt redox mediator, [Co(bpyPY4)]^2+/3+, based on a hexadentate polypyridyl ligand, was developed. Dye-sensitized solar cells (DSCs) made with this redox mediator showed improved stability and slightly higher efficiencies compared to [Co(bpy)₃]^2+/3+-based devices. Long-term stability evaluation of DSCs based on [Co(bpyPY4)]^2+/3+ revealed excellent stability under full irradiation conditions (see picture).

Published online, DOI: 10.1002/anie.201300070 – Read now No. 21/2013.

Pores for thought: Porous nitrogen-doped carbon materials (HTC Carbon with PILs) composed of spherical nanoparticles, and also those with Au–Pd core–shell nanoparticles embedded (Au–Pd@N-Carbon) were synthesized. These materials can be prepared from sugars by hydrothermal carbonization (160–200 °C) in the presence of poly(ionic liquid)s (PILs), which act as a stabilizer, pore-generating agent, and nitrogen source.

[Communication]
Pengfei Zhang, Jiayin Yuan, Tim-Patrick Fellinger, Markus Antonietti, Haoran Li, Yong Wang
Angew. Chem. Int. Ed., Apr 16, 2013, DOI: 10.1002/anie.201301069. Read article.

Long C-C bonds: Analysis of the 1064 nm Raman vibrational spectrum of K₂[TCNE]₂ possessing isolated π-[TCNE]₂²⁻ (TCNE=tetracyanoethylene) dimers shows several low-energy symmetric intradimer breathing modes at 198, 173, 155, 131, 107, and 85 cm⁻¹. These data confirm the presence of a long two-electron/four-center C-C bond (see picture).

[Communication]
Juan Casado, Paula Mayorga Burrezo, Francisco J. Ramírez, Juan T. López Navarrete, Saul H. Lapidus, Peter W. Stephens, Hoa-Lan Vo, Joel S. Miller, Fernando Mota, Juan J. Novoa
Angew. Chem. Int. Ed., Apr 16, 2013, DOI: 10.1002/anie.201207813. Read article.

Using the 3D structural depiction of the environment around the absorbing atom provided by X-ray absorption near-edge structure (XANES) spectroscopy and DFT calculations, the molecular-scale structure of the TiO₂-supported molybdenum oxide catalysts has been unraveled and it consists of Mo octahedra arranged in a six-membered ring structure.

Received January 21, 2013, published online May 07, 2013, DOI: 10.1002/anie.201300538 – read now.

Did you read this article? Was it important to you? Let us know...

The one-pot synthesis of a molecular Solomon link assembles four iron(II) cations, four bis-aldehyde and four bis-amine building blocks to generate two interwoven 68-membered-ring macrocycles with four crossings in 75 % isolated yield. The synthesis of the Solomon link, and an earlier pentafoil knot, demonstrate that cyclic helicates of different sizes can act as highly efficient and effective scaffolds for intricate molecular topologies.

Received March 29, 2013, published online May 06, 2013, DOI: 10.1002/anie.201302634 – read now.

Did you read this article? Was it important to you? Let us know...

My favorite food is Tofu. If I were not a scientist, I would be a businessman selling green tea.

[Author Profile]

Angew. Chem. Int. Ed., Apr 15, 2013, DOI: 10.1002/anie.201302110. Read article.

My motto is keep on trying. My favorite time of day is the half-hour after I wake up, but before I get up.

[Author Profile]

Angew. Chem. Int. Ed., Apr 15, 2013, DOI: 10.1002/anie.201301619. Read article.

My greatest achievement has been finishing a marathon run in reasonable time. Guaranteed to make me laugh is Loriot (German humorist).

[Author Profile]

Angew. Chem. Int. Ed., Apr 15, 2013, DOI: 10.1002/anie.201301621. Read article.

Ken Mukai, Daisuke Urabe, Satoshi Kasuya, Naoto Aoki, Masayuki Inoue*

19 in 19: A convergent total synthesis of 19-hydroxysarmentogenin has been achieved, starting from three simple fragments. The desired product was synthesized in 19 steps from the AB ring with the installation of six stereocenters and the formation of three C–C bonds.

Published online, DOI: 10.1002/anie.201302067 – Read now No. 20/2013.

Haiyin Liu, Angus P. R. Johnston*

A molecular sensor has been developed to probe the internalization of proteins and nanoparticles into live cells. This simple, high-throughput technique is compatible with cell phenotyping and is independent of the cellular fate of the material.

Published online, DOI: 10.1002/anie.201301243 – Read now No. 22/2013.

Akira Ueda, Shuichi Suzuki, Kenta Yoshida, Kozo Fukui, Kazunobu Sato, Takeji Takui*, Kazuhiro Nakasuji, Yasushi Morita*

A phenalenyl radical with six methoxy groups, which were introduced symmetrically, has been synthesized. The extensively delocalized and highly symmetric electronic-spin system was studied with advanced cw-/pulsed-ESR techniques, thereby giving an experimental model to explore molecular quantum spin simulators with novel quantum coherence attributable to the extremely high degeneracy of the nuclear spin states owing to the eighteen equivalent protons.

Published online, DOI: 10.1002/anie.201301435 – Read now

Tao Shen, Teng Wang, Chong Qin, Ning Jiao*

Three in one blow! A novel direct transformation of alkynes into nitriles by a silver-catalyzed nitrogenation reaction through C≡C bond cleavage has been developed. This research provides both a new application for alkynes in organic synthesis, and valuable mechanistic insights into nitrogenation chemistry.

Published online, DOI: 10.1002/anie.201300193 – Read now

Yuehui Li, Xianjie Fang, Kathrin Junge, Matthias Beller*

Putting CO₂ to work: Carbon dioxide is shown to be a general and selective methylating reagent for secondary and primary, aromatic and aliphatic amines under reductive conditions. A variety of tertiary amines are obtained from CO₂ and commercially available silanes in high yields with good tolerance to nitrile, olefin, ether, ester, and hydroxy groups.

Published online, DOI: 10.1002/anie.201301349 – Read now

A novel silver-catalyzed click synthesis of pyrroles by the co-cyclization of terminal alkynes and isocyanides has been developed. From the synthetic point of view, this protocol represents an extremely simple, efficient, and atom-economic way to construct substituted pyrroles in good yields with high selectivity, which complements the click method for the rapid construction of multifunctional heterocycles.

Received March 28, 2013, published online April 29, 2013, DOI: 10.1002/anie.201302604 – read now.

Did you read this article? Was it important to you? Let us know...

Jun Wang, Hai-xia Zhong, Yu-ling Qin, Xin-bo Zhang*

Oxygen evolution: A 3D nickel foam/porous carbon/anodized nickel electrode was designed for the oxygen evolution reaction (see picture). The conductive porous carbon membrane plays a key role, which is derived from zeolite imidazolate framework and subsequently employed as interlayer to both protect the inner instable Ni foam and support the outermost oxygen-evolving Ni catalyst layer.

Published online, DOI: 10.1002/anie.201301066 – Read now No. 20/2013.

In a spare hour, I read outside chemistry. If I could be any age I would be young again.

[Author Profile]

Angew. Chem. Int. Ed., Apr 08, 2013, DOI: 10.1002/anie.201301116. Read article.

The solid-phase synthesis of the potent antitumoral thiocoraline is accomplished for the first time by a combined approach involving chemical and enzymatic methods. With a sequence highly rich in Cys, consecutive NMe amino acids, and a bicyclic structure formed by a disulfide bridge flanked by two thioester moieties, an orchestrated protection group scheme becomes the cornerstone for the successful synthesis for thiocoraline. One-pot cleavage of the phenylacetamidomethyl moiety by the immobilized penicillin G acylase and disulfide formation are the key steps of the synthetic strategy.

Received February 27, 2013, published online April 25, 2013, DOI: 10.1002/anie.201301708 – read now. No. 22/2013.

Did you read this article? Was it important to you? Let us know...

Electron diffraction measurements on a set of homonuclear 55-atom transition-metal clusters covering essentially all 3d and 4d elements are reported. The diffraction data obtained for cluster anions in gas phase at 95K show four main structure types. Elements with the same bulk lattice morphology generally have a common cluster structure type. To rationalize this, cluster geometries have been determined by fitting structural models from density functional theory calculations to the diffraction data. The four structure types differ in maximum atomic coordination numbers in analogy to the coordination numbers in the corresponding bulk lattices.

Received March 14, 2013, published online May 09, 2013, DOI: 10.1002/anie.201302165 – read now.

Did you read this article? Was it important to you? Let us know...

Putting CO₂ to work: Carbon dioxide is shown to be a general and selective methylating reagent for secondary and primary, aromatic and aliphatic amines under reductive conditions. A variety of tertiary amines are obtained from CO₂ and commercially available silanes in high yields with good tolerance to nitrile, olefin, ether, ester, and hydroxy groups.

[Communication]
Yuehui Li, Xianjie Fang, Kathrin Junge, Matthias Beller
Angew. Chem. Int. Ed., Apr 05, 2013, DOI: 10.1002/anie.201301349. Read article.

Supra-sensitivity: Dynamic nuclear polarization (DNP) enhanced solid-state NMR spectroscopy was performed on self-assembled peptide nanotubes. This approach yields significant experimental time savings (about five orders of magnitude; see picture) and was used to exemplify the feasibility of supramolecular structural studies of organic nanoassemblies at an atomic scale using DNP-enhanced solid-state NMR spectroscopy.

[Communication]
Hiroki Takahashi, Bastien Viverge, Daniel Lee, Patrice Rannou, Gaël De Paëpe
Angew. Chem. Int. Ed., Apr 05, 2013, DOI: 10.1002/anie.201210093. Read article.

The first transition-metal-catalyzed cycloaddition of isocyanides and unactivated terminal alkynes has been realized by the discovery of silver carbonate (Ag₂CO₃) as a unique and robust catalyst. This protocol for silver-catalyzed reaction is highly efficient allowing a broad range of terminal and internal alkynes to react with isocyanides under base- and ligand-free conditions, regioselectively generating synthetically useful 2,3-disubstituted and 2,3,4-trisubstituted pyrroles in good to high yields.

Received March 11, 2013, published online May 06, 2013, DOI: 10.1002/anie.201302024 – read now.

Did you read this article? Was it important to you? Let us know...

Three in one blow! A novel direct transformation of alkynes into nitriles by a silver-catalyzed nitrogenation reaction through C≡C bond cleavage has been developed. This research provides both a new application for alkynes in organic synthesis, and valuable mechanistic insights into nitrogenation chemistry.

[Communication]
Tao Shen, Teng Wang, Chong Qin, Ning Jiao
Angew. Chem. Int. Ed., Apr 03, 2013, DOI: 10.1002/anie.201300193. Read article.

What I look for first in a publication is the abstract and schemes. The most important thing I learned from my parents is to work hard.

[Author Profile]

Angew. Chem. Int. Ed., Apr 02, 2013, DOI: 10.1002/anie.201300417. Read article.

A dual-responsive block-statistical copolymer was synthesized by integrated ring-opening and atom transfer radical polymerizations. This copolymer condenses nucleic acids into self-assembled nanoparticles that undergo triggered changes in response to intracellular microenvironments. Under acidifying conditions such as in endosomes after intracellular uptake, the materials increase their protonation state, facilitating endosomal escape. Under the reducing conditions of cell cytosol, polyplexes are cleaved to release a stabilizing hydrophobic domain, prompting nucleic acid cargo release. Effective plasmid and siRNA delivery to cultured mammalian cells and mouse brain is demonstrated using this optimized formulation that combines reversible hydrophobization with statistical hydrophilization.

Received March 06, 2013, published online April 16, 2013, DOI: 10.1002/anie.201301896 – read now. No. 20/2013.

Did you read this article? Was it important to you? Let us know...

Combining the classical cobalt carbonyl hydride configuration with the question of how, mechanistically, cobalt hydrides effect the formation of H₂, a specific, structurally protecting and potentially electronically active ferrocenyldiphosphane co-ligand at Co(CO)₂H was used to characterize the native metal hydride, the one-electron oxidized form, and the sensitive, metal hydride-free byproduct of H₂ formation by structure analysis and low-temperature spectroelectrochemistry. The first identification of all elementary steps in the homolytic pathway for oxidative carbonylmetal hydride conversion is reported.

Received February 27, 2013, published online May 10, 2013, DOI: 10.1002/anie.201301706 – read now.

Did you read this article? Was it important to you? Let us know...

My favorite quote is “when the going gets tough, the tough get going”. My favorite time of day is early morning.

[Author Profile]

Angew. Chem. Int. Ed., Mar 14, 2013, DOI: 10.1002/anie.201300854. Read article.

When I was eighteen I wanted to be a football player for Real Madrid. If I could be described as an animal it would be a fighting bull.

[Author Profile]

Angew. Chem. Int. Ed., Mar 14, 2013, DOI: 10.1002/anie.201300418. Read article.

A method of forming tetrameric aggregates with an ααββ structure is developed using stereoisomeric bidomain oligomers for the α and β subunits. The α subunit contains a (M)-amidohelicene tetramer domain and a (M)-ethynylhelicene pentamer domain, and the β subunit contains a (M)-amidohelicene tetramer domain and a (P)-ethynylhelicene pentamer domain. Each bidomain oligomers was dimeric in chloroform, and mixing of the two solutions gave a tetrameric ααββ aggregate by heteroaggregation at the ethynyl domain. The tetrameric aggregate reversibly changed its structure between the dimeric homoaggregates on heating and cooling. Gelation occurred in toluene by the polymerization of the tetrameric aggregate.

Received February 19, 2013, published online April 09, 2013, DOI: 10.1002/anie.201301463 – read now. No. 20/2013.

Did you read this article? Was it important to you? Let us know...

CdS-based visible-light photocatalysts have intrinsic photocorrosion problems. Another great concern is the toxicity of leached Cd²⁺ ions. In this work, we show that by simply coating the CdS particles with a thin layer of amorphous carbon, the above problems can be largely solved. We demonstrate the concept by synthesizing novel carbon-coated CdS petalous particles using a one-pot solvothermal method. The carbon nanocoating serves multifold functions including surface protection of CdS, visible-light absorption enhancement and facilitated separation of photogenerated charges. As a result, this CdS–C nanohybrid photocatalyst exhibits significantly enhanced photostability and photocatalytic activity.

Received February 27, 2013, published online April 05, 2013, DOI: 10.1002/anie.201301709 – read now. No. 21/2013.

Did you read this article? Was it important to you? Let us know...

An uphill climb: The title systems show fast, reversible bending with a large strain. Such hinges can power remote-controlled soft robots, including foldable origami structures, Venus flytrap-inspired grippers that can pick up delicate objects, and inchworm walkers that can crawl up a 50° incline (see picture).

[Communication]
Maika Moua, Ryan R. Kohlmeyer, Jian Chen
Angew. Chem. Int. Ed., Mar 12, 2013, DOI: 10.1002/anie.201210232. Read article.

A heterobimetallic high-valent CuNi bis(µ–oxo) complex is prepared by the reduction of a nickel superoxo complex with a Cu(I) reductant, and characterized by low–temperature UV/Vis, resonance Raman, electron paramagnetic resonance, and X–ray absorption spectroscopy in conjunction with reactivity and DFT studies. Unlike typical homodinuclear high–valent [M₂(µ–O)₂]ⁿ⁺ cores, which have electrophilic oxo groups, the oxo groups in [Cu(µ–O)₂Ni]²⁺ behave as nucleophiles, and can initiate deformylation of aldehydes. Mixed–metal bis(µ–oxo) cores are, therefore, viable intermediates during the deformylation of fatty aldehydes by cyanobacterial aldehyde decarbonylase, where a heterodinuclear cofactor has been suggested.

Received January 31, 2013, published online April 15, 2013, DOI: 10.1002/anie.201300861 – read now. No. 21/2013.

Did you read this article? Was it important to you? Let us know...

Peptide self-assemblies have great potential for applications in nanotechnology. However, atomic-scale structure determination is not straightforward, which is essentially due to the difficulty associated with using X-ray crystallography. Dynamic nuclear polarization (DNP) enhanced solid-state NMR was performed on self-assembled peptide nanotubes prepared with a new DNP-friendly method. This approach achieves uniform distribution of polarizing agents around the sample without sample dilution and yields significant experimental time-savings of five orders of magnitude. This super-sensitivity was used to exemplify the feasibility of supramolecular structural studies of organic nanoassemblies using multidimensional ¹³C NMR at natural isotopic abundance.

Received December 18, 2012, published online April 05, 2013, DOI: 10.1002/anie.201210093 – read now.

Did you read this article? Was it important to you? Let us know...

My biggest motivation is curiosity. Guaranteed to make me smile is when my predictions come true.

[Author Profile]

Angew. Chem. Int. Ed., Mar 07, 2013, DOI: 10.1002/anie.201300198. Read article.

Silke Gandor, Stephanie Reisewitz, Muthukumaran Venkatachalapathy, Giuseppe Arrabito, Martina Reibner, Hendrik Schröder, Katharina Ruf, Christof M. Niemeyer, Philippe I. H. Bastiaens*, Leif Dehmelt*

Taking the bait: Protein interaction arrays were generated in living cells by the interaction of bait-presenting artificial receptor constructs (bait-PARCs) with micrometer-scaled antibody surface patterns (see figure). This method was applied to simultaneously monitor the interaction kinetics of a prey protein with two distinct bait proteins in individual living cells.

Published online, DOI: 10.1002/anie.201209127 – Read now

My greatest achievement has been getting paid to do what I do. Guaranteed to make me laugh is the comedy series “Absolutely Fabulous”.

[Author Profile]

Angew. Chem. Int. Ed., Feb 28, 2013, DOI: 10.1002/anie.201210109. Read article.

Photocatalysts active under near-infrared (NIR) light have been unknown. The libethenite Cu₂(OH)PO₄ absorbs strongly in the NIR light region and is an effective photocatalyst under NIR light irradiation, which decomposes 2,4-dichlorophenol in aqueous solution. Cu₂(OH)PO₄ consists of distorted CuO₄(OH)₂ octahedra sharing their corners with distorted CuO₄(OH) trigonal bipyramids. The NIR-light-driven photocatalytic ability of Cu₂(OH)PO₄ is due to a facile transfer of the photogenerated electrons from the trigonal bipyramidal Cu(II) sites to the adjacent octahedral Cu(II) sites.

Received February 14, 2013, published online March 28, 2013, DOI: 10.1002/anie.201301306 – read now.

Did you read this article? Was it important to you? Let us know...

A meta-terphenyl-based achiral conjugated polymer bearing carboxy groups self-associated to form a racemic double helix in the solid state, whereas with chiral amines the polymer formed a unique one-handed double helix in solution, in which each strand sandwiched a pair of chiral amines through a cyclic hydrogen-bonding network. The chiral information of the amines is transferred to the polymer backbones with remarkable amplification of the helical chirality.

Received February 04, 2013, published online April 05, 2013, DOI: 10.1002/anie.201301005 – read now. No. 20/2013.

Did you read this article? Was it important to you? Let us know...

An efficient and general synthetic route to the elusive epoxyisoprostanoid phospholipids PECPC and PEIPC, along with the isoprostanoids EC and EI is reported, relying on a number of stereo- and chemoselective steps, including a C–H insertion for rapid construction of the cyclopentanone ring. The synthesized compounds display unprecedented biological activity in reducing the secretion of pro-inflammatory cytokines.

Received January 28, 2013, published online April 16, 2013, DOI: 10.1002/anie.201300739 – read now. No. 20/2013.

Did you read this article? Was it important to you? Let us know...

A general strategy for producing recombinant histones with site-specific serine phosphorylation is developed through engineering phosphoseryl-tRNA synthetase and an elongation factor. Serine-phosphorylated nucleosomes provide the first direct evidence for crosstalk between phosphorylation and acetylation in histone. This strategy should facilitate the study of histone phosphorylation and cross-regulatory mechanisms.

Received January 21, 2013, published online March 26, 2013, DOI: 10.1002/anie.201300531 – read now. No. 22/2013.

Did you read this article? Was it important to you? Let us know...

My biggest motivation is the excitement of discovery. My favorite piece of research is a discovery that you had not intended to make in the first place.

[Author Profile]

Angew. Chem. Int. Ed., Feb 20, 2013, DOI: 10.1002/anie.201209484. Read article.

My favorite principle is Occam’s razor. I am waiting for the day when someone will discover real cold fusion.

[Author Profile]

Angew. Chem. Int. Ed., Feb 10, 2013, DOI: 10.1002/anie.201209932. Read article.

My greatest achievement has still not been published I hope! My biggest motivation is curiosity.

[Author Profile]

Angew. Chem. Int. Ed., Feb 10, 2013, DOI: 10.1002/anie.201209931. Read article.

I can never resist a delicious French dessert. My biggest motivation is to learn something new every day.

[Author Profile]

Angew. Chem. Int. Ed., Feb 05, 2013, DOI: 10.1002/anie.201210061. Read article.

Cucurbit[14]uril, the largest cucurbit[n]uril member with 14 normal glycoluril units linked by 28 methylene bridges using the traditional synthetic routes. However, it seems to be formed from 14 units of the –glycoluril-(CH₂)₂– moiety with a 360° twist. As a consequence, it does not have a normal cavity like the most cucubit[n]urils, and looks to have a folded, figure-of-eight conformation. We are naming it twisted cucurbit[14]uril (tQ[14]).

Coming soon.

A word in urea: A strategy of mimicking the scaffold and metal coordination behavior of oligo-2,2'-bipyridine ligands was used to obtain a triple anion helicate from a bis(biurea) receptor and phosphate ions. The successful assembly of the triple helical structure provides guidelines for the design of new anion ligands by taking advantage of the similarities of metal and anion coordination.

[Communication]
Shaoguang Li, Chuandong Jia, Biao Wu, Qiong Luo, Xiaojuan Huang, Zaiwen Yang, Qian-Shu Li, Xiao-Juan Yang
Angew. Chem. Int. Ed., May 10, 2011, DOI: 10.1002/anie.201100593. Read article.