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1.
Hai‐Lei Cui Jing Peng Xin Feng Wei Du Kun Jiang Ying‐Chun Chen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(7):1574-1577
The first highly enantioselective allylic–allylic alkylation of α,α‐dicyanoalkenes and Morita–Baylis–Hillman carbonates by dual catalysis of (DHQD)2AQN and (S)‐BINOL has been investigated. Excellent stereoselectivities have been achieved for a broad spectrum of substrates (d.r. > 99:1, up to 99 % ee). The multifunctional allylic products could be efficiently converted to a range of complex chiral cyclic frameworks. EWG=electron‐withdrawing group, (DHQD)2AQN=hydroquinidine (anthraquinone‐1,4‐diyl) diether, (S)‐BINOL =(S)‐(?)‐1,1′‐bi‐2‐naphthol.
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Erik Schwartz Vincenzo Palermo Dr. Chris E. Finlayson Dr. Ya‐Shih Huang Matthijs B. J. Otten Andrea Liscio Dr. Sara Trapani Irene González‐Valls Patrick Brocorens Dr. Jeroen J. L. M. Cornelissen Dr. Kalina Peneva Dr. Klaus Müllen Prof. Dr. Frank C. Spano Prof. Dr. Arkady Yartsev Prof. Sebastian Westenhoff Dr. Richard H. Friend Prof. Dr. David Beljonne Dr. Roeland J. M. Nolte Prof. Dr. Paolo Samorì Prof. Dr. Alan E. Rowan Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(11):2536-2547
Exciton migration! Spectroscopic analyses and extensive molecular dynamics studies revealed a well‐defined 41 helix in which the perylene molecules (see figure) form four “helter‐skelter‐like” overlapping pathways along which excitons and electrons can rapidly migrate.
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Up and down: Differential sensing of serine and tyrosine is achieved with aligned CdS nanowire arrays by exploring the pH‐dependent PL behavior of the nanowire arrays toward exposure to the two amino acid solutions (see picture).
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Paolo Ranzieri Dr. Alberto Girlando Prof. Silvia Tavazzi Prof. Marcello Campione Prof. Luisa Raimondo Dr. Ivano Bilotti Dr. Aldo Brillante Prof. Raffaele G. Della Valle Prof. Elisabetta Venuti Prof. 《Chemphyschem》2009,10(4):657-663
Two 4T: Low‐frequency micro‐Raman spectroscopy coupled with lattice dynamics calculations is an invaluable tool for investigating polymorphism in organic semiconductors. The Raman spectra of the low‐temperature (LT) and high‐temperature (HT) polymorphs of α‐quaterthiophene (4T) are presented and interpreted (see picture). Raman mapping is applied to investigate the phase purity.
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Eleftheria Neofotistou Christos D. Malliakas Dr. Pantelis N. Trikalitis Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(18):4523-4527
Gas storage : A new, sulfone‐functionalized dicarboxylate‐based ligand (see figure) is capable of directing the formation of novel metal–organic frameworks with unprecedented organic and inorganic secondary building units. A high CO2 uptake with remarkable selectivity over CH4, N2, and H2 was observed at near‐ambient temperature.
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Liang‐Feng Yao Min Shi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3875-3881
Cascade reactions : Lewis acid catalyzed cascade reactions of 1,6‐diynes and 1,6‐enynes with arylvinylidenecyclopropanes produce polycyclic compounds and isopropylidene‐3,3‐diarylcyclobut‐1‐enylmethyl derivatives (see scheme) in good to high yields along with a PtCl2‐catalyzed cyclization and a Cu(OAc)2 ? H2O‐catalyzed Eglinton coupling reaction.
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Zhihua Chen Makoto Furutachi Yuko Kato Shigeki Matsunaga Dr. Masakatsu Shibasaki Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(12):2218-2220
Two metal cooperation : A homodinuclear Co2–Schiff base complex Co2(OAc)2– 1 promoted the asymmetric 1,4‐addition of β‐keto esters to alkynones under solvent‐free conditions in air (see scheme). The reactions proceeded without air or moisture sensitivity in high yields and with high enantioselectivities (99–91 % ee) at room temperature under highly concentrated conditions (neat–20 M ) with 0.1–2.5 mol % catalyst loading.
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Mohamed E. El‐Khouly Dr. Jung Hoon Kim Dr. Kwang‐Yol Kay Prof. Dr. Chan Soo Choi Dr. Osamu Ito Prof. Dr. Shunichi Fukuzumi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(21):5301-5310
Fast moving : A new pentad (see figure) composed of silicon phthalocyanine (SiPc), as electron donor, that is connected with two units of naphthalenediimide (NDI) and fullerene C60, as electron acceptors, undergoes fast and efficient charge‐separation processes via the NDI and SiPc singlet excited states.
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Satoshi Ueno Dr. Ryosuke Shimizu Ryoichi Kuwano Prof. 《Angewandte Chemie (International ed. in English)》2009,48(25):4543-4545
Gone fishing : When propiophenone and related ethyl ketones are treated with morpholine in the presence of K3PO4, chlorobenzene, and [Ni(cod)2]/PMe3 catalyst, a carbon–nitrogen bond is formed selectively at the β position (see scheme; cod=cycloocta‐1,5‐diene). Secondary amines were employed as substrates to give the corresponding β‐enaminones.
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Hiroaki Kitagishi Dr. Yasuaki Kakikura Hiroyasu Yamaguchi Dr. Koji Oohora Akira Harada Prof. Dr. Takashi Hayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1271-1274
Supramolecular protein polymers : When a heme moiety was introduced to the surface of an apo‐cytochrome b562(H63C) mutant, supramolecular polymers formed through noncovalent heme–heme pocket interactions. The incorporation of a heme triad as a pivot molecule in the protein polymer further led to a two‐dimensional protein network structure, which was visualized by tapping‐mode atomic force microscopy (see picture).
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Jörn Schmedt auf der Günne Dr. 《Angewandte Chemie (International ed. in English)》2009,48(19):3401-3403
On an atomic scale and with high sensitivity, solid‐state NMR spectroscopy can provide information about the electronic spin density and coupling mechanisms in paramagnetic compounds. The picture shows how the hyperfine splitting collapses through relaxation. Insights into which compounds are suitable and which approximations have to be made are given.
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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.
17.
Elangovan Elamparuthi Torsten Linker Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(10):1853-1855
Phosphorus meets carbohydrates : Dimethyl phosphite reacts with ceric(IV) ammonium nitrate (CAN) to give phosphonyl radicals that add to glycals 1 . The derivatives 2 were isolated in high yields and during a subsequent Horner–Emmons reaction underwent an interesting elimination to give 3,6‐dihydro‐2H‐pyrans 3 . The short sequence with simple precursors is applicable to the transformation of hexoses, pentoses, and disaccharides. Bn=benzyl.
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Zhiyong Jiang Dr. Yuanyong Yang Yuanhang Pan Yujun Zhao Hongjun Liu Choon‐Hong Tan Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(19):4925-4930
Constructing α‐stereogenic amides and ketones : The highly regioselective and enantioselective conjugate addition of 1,3‐dicarbonyl compounds to 1,4‐dicarbonyl but‐2‐enes has been developed with the chiral bicyclic guanidine as catalyst (ee values up to 97 %; see scheme).
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Qiufeng Huang Dr. Ruimao Hua Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3817-3822
Economical atoms : 2‐Cyclopenten‐1‐ones, 5‐alkylidenefuran‐2(5 H)‐ones and indan‐1‐ones have been synthesized by atom‐economic reductive cyclocarbonylation of internal alkynes with carbon monoxide catalyzed by [{RhCl(CO)2}2]/CO(NH2)2 in the presence of water (see scheme).
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Jörg Stierstorfer Dr. Karina R. Tarantik Dipl.‐Chem. Thomas M. Klapötke Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(23):5775-5792
A new way to make a bang : Several functionalized 1‐ethyl‐5‐aminotetrazoles, 1‐ethyl‐5‐nitrimino‐tetrazoles, and copper complexes have been synthesized and their chemical and energetic properties have been comprehensively characterized. The compounds belong to all classes of “energetic materials”: explosives, propellants, and pyrotechnics.