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Bryon Simmons Abbas M. Walji Dr. David W. C. MacMillan Prof. 《Angewandte Chemie (International ed. in English)》2009,48(24):4349-4353
United in effort : The combined application of iminium (Im) and enamine (En) catalysts can effect a range of valuable asymmetric transformations including 1,2‐hydroamination, ‐hydro‐oxidation, and ‐amino‐oxidation of olefins (see picture). An enantioselective organocascade catalysis was also applied in the synthesis of a complex natural product.
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Patrick J. M. Stals Maarten M. J. Smulders Rafael Martín‐Rapún Dr. Anja R. A. Palmans Dr. E. W. Meijer Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(9):2071-2080
Molecular organization : Chiral benzene tricarboxamides with methyl substituents at defined positions self‐assemble into supramolecular polymers of preferred helicity by three‐fold α‐helical‐type hydrogen bonding. The odd–even effect is operative and all derivatives are liquid crystalline showing a Colho phase (see figure).
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Antonio Otero Prof. Dr. Juan Fernández‐Baeza Agustín Lara‐Sánchez Carlos Alonso‐Moreno Isabel Márquez‐Segovia Luis F. Sánchez‐Barba Ana M. Rodríguez 《Angewandte Chemie (International ed. in English)》2009,48(12):2176-2179
With a sting in its tail : An enantiopure neodymium complex (see scheme) acts as an efficient single‐site initiator for the controlled ring‐opening polymerization of rac‐lactide, forming isotactic polyester. The heteroscorpionate complex was characterized spectroscopically and by X‐ray diffraction.
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Herbert Meier Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):3911-3913
En route to molecular electronics : As extended, conjugated oligomers are desirable for molecular electronics, their electrical conductance should display a low attenuation factor. Zinc‐complexed oligo(ethynyleneporphyrindiylethynylene)s have been prepared that are distinguished by ultralow attenuation factors in single‐molecule conductance.
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Benito Alcaide Prof. Dr. Pedro Almendros Dr. Teresa Martínez del Campo Dipl.‐Chem. M. Teresa Quirós Dipl.‐Chem. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3344-3346
First insights into the reaction between a Baylis–Hillman adduct and an allene moiety have been obtained from the novel domino heterocyclization/cross‐coupling reaction of α‐allenols and Baylis–Hillman acetates, which furnishes [(2,5‐dihydrofuran‐3‐yl)methyl]acrylate derivatives in moderate to good yields.
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Min Wang Dr. Jian Gao Dr. Pavel Müller Dr. Bernd Giese Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(23):4232-4234
Caught on the hop : In multistep electron transfer (ET) reactions through peptides, aliphatic amino acids can also act as relay stations. With cysteine, the reaction occurs as a proton‐coupled electron transfer (PCET) with water used as a mediator for the proton transfer (see picture).
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Frédéric Coutrot Dr. Eric Busseron 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(21):5163-5163
A domino effect from one extremity to the other is observed in a large‐amplitude mannosyl [2]rotaxane molecular machine. In their Communication on page 5186 ff., F. Coutrot and E. Busseron describe the efficient preparation of new [2]rotaxane molecular machines containing anilinium and either mono‐ or disubstituted pyridinium amide stations. In the case of the disubstituted pyridinium amide, the macrocycle shuttles from the anilinium to the pyridinium upon deprotonation and causes an impressive flipping of the chair conformation of the glucidic moiety.
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Marco d'Ischia Prof. Alessandra Napolitano Prof. Alessandro Pezzella Dr. Paul Meredith Prof. Tadeusz Sarna Prof. 《Angewandte Chemie (International ed. in English)》2009,48(22):3914-3921
A black whole : The black insoluble biopolymer eumelanin is prepared through the oxidative polymerization of 5,6‐dihydroxyindoles (see scheme). It has a largely unknown heterogeneous structure and unique optoelectronic properties. Current structural models are presented and possible applications are discussed.
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Hana Robson Marsden Nina A. Elbers Paul H. H. Bomans Dr. Nico A. J. M. Sommerdijk Dr. Alexander Kros Dr. 《Angewandte Chemie (International ed. in English)》2009,48(13):2330-2333
Let's get together : A minimal model system was developed to mimic the SNARE‐protein‐mediated fusion of biological membranes (see picture). Fusion between two populations of liposomes is controlled by a pair of complementary lipidated oligopeptides that form noncovalent coiled‐coil complexes and thereby force the membranes into close proximity to promote fusion. The model system displays the key characteristics of in vivo fusion events.
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Aubry K. Miller Dr. 《Angewandte Chemie (International ed. in English)》2009,48(18):3221-3223
Adding up : A recent total synthesis of bryostatin 16 is highlighted by two transition‐metal‐catalyzed addition reactions. The first forges the B ring while establishing its relative stereochemistry. The second closes the macrocycle with a rare isomerization. These reactions neither require substrate activation nor do they generate byproducts. The powerful macrocyclization should be considered alongside more traditional methods.