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Andreas Grauer Andreas Späth Dawei Ma Prof. Dr. Burkhard König Prof. Dr. 《化学:亚洲杂志》2009,4(7):1134-1140
Making circles with N and O : Cyclic tripeptides containing an unnatural Cα‐tetrasubstituted THF amino acid are prepared by copper(I) and palladium(0)‐catalyzed N‐ and O‐arylation reactions. The reactions give access to side chain‐modified derivatives of the unnatural amino acid and macrocyclic peptidomimetics.
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Fuat E. Celik Tae‐Jin Kim Dr. Alexis T. Bell Prof. 《Angewandte Chemie (International ed. in English)》2009,48(26):4813-4815
Carbonylation gets a phase lift : The usual liquid‐phase, high‐pressure processes for carbonylating formaldehydes are avoided in a novel vapor‐phase reaction. Using an acid zeolite (Faujasite) at near‐atmospheric pressure dimethoxymethane (DMM; the dimethyl acetal of formaldehyde; see scheme) is carbonylated to produce methyl methoxyacetate (MMAc). This approach provides a new route to ethylene glycol under mild conditions.
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Dapeng Cao Prof. Dr. Jianhui Lan Wenchuan Wang Prof. Berend Smit Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4730-4733
Quick on the uptake : A multiscale theoretical method predicts that the gravimetric adsorption capacities of H2 in Li‐doped covalent organic frameworks based on the building blocks shown (Li violet, H white, B pink, C green, O red, Si yellow) can reach nearly 7 % at T=298 K and p=100 bar, suggesting that these Li‐doped materials are promising adsorbents for hydrogen storage.
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Andreas Lohr Dr. Matthias Grüne Dr. Frank Würthner Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3691-3705
Dipolar aggregation : Examples of a novel class of tweezer molecules have been constructed through the tethering of two dipolar merocyanine chromophores. The electrostatic‐interaction‐directed self‐assembly of these tweezers affords centrosymmetric bimolecular complexes with a unique aggregate geometry of four π‐stacked chromophores (see picture) with an alternating arrangement of their dipole moments and very high dimerization constants, even in the good solvating solvent chloroform.
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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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Caue Ribeiro Dr. Cristiano M. Barrado Dr. Emerson R. de Camargo Prof. Dr. Elson Longo Prof. Dr. Edson R. Leite Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(9):2217-2222
The oriented attachment (OA) mechanism has been investigated as an important process in the formation of anisotropic nanostructures such as depicted. The results showed that the control of a desired phase in this system may be attained by the control of OA mechanism through pH value, obtaining several morphologies.
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Feng Gao Dr. Xuxu Yan Karine Auclair Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(9):2064-2070
Just five steps! The synthesis of a phosphonate‐linked aminoglycoside‐coenzyme A derivative (see scheme) that includes a Michael addition in water has been realized in just five steps.
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Gregor Hagelueken Dr. W. John Ingledew Dr. Hexian Huang Biljana Petrovic‐Stojanovska Chris Whitfield Prof. Hassane ElMkami Dr. Olav Schiemann Dr. James H. Naismith Prof. 《Angewandte Chemie (International ed. in English)》2009,48(16):2904-2906
Distance fingerprinting : Pulsed electron–electron double resonance spectroscopy (PELDOR) is applied to the octameric membrane protein complex Wza of E. coli. The data yielded a detailed distance fingerprint of its periplasmic region that compares favorably to the crystal structure. These results provide the foundation to study conformation changes from interaction with partner proteins.
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Chen Zhao Yuan Kou Prof. Dr. Angeliki A. Lemonidou Prof. Dr. Xuebing Li Dr. Johannes A. Lercher Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):3987-3990
Oil and water : A new energy‐efficient and atom‐economical catalytic route for the production of alkanes and methanol by upgrading the phenolic fraction of bio‐oil has been developed. The one‐pot aqueous‐phase hydrodeoxygenation process is based on two catalysts facilitating consecutive hydrogenation, hydrolysis, and dehydration reactions.
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Nathanaëlle Schneider Dr. Markus Finger Dr. Christian Haferkemper Stéphane Bellemin‐Laponnaz Dr. Peter Hofmann Prof. Dr. Lutz H. Gade Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(9):1609-1613
Rhodium silylenes , which are generated by double Si–H activation at the metal, are involved in a low‐activation‐barrier mechanism of the hydrosilylation of ketones with R2SiH2. A DFT‐based study of reaction mechanisms accounts for the experimental observations, notably the rate enhancement for R2SiH2 over R3SiH and an inverse kinetic isotope effect.
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Nathalie M. Rocher Dr. Ekaterina I. Izgorodina Dr. Thomas Rüther Dr. Maria Forsyth Prof. Douglas R. MacFarlane Prof. Theo Rodopoulos Dr. Michael D. Horne Alan M. Bond Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3435-3447
Aluminium speciation : Aluminium speciation in NTf2 ionic liquids has a strong influence on its electrodeposition from the liquid mixture. This work probed the nature of these species and proposes that the electroactive species involved are either [AlCl3(NTf2)]? or [AlCl2(NTf2)2]? (e.g., see figure).
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Niels Elders Eelco Ruijter Dr. Frans J. J. de Kanter Dr. Elwin Janssen Martin Lutz Dr. Anthony L. Spek Prof. Dr. Romano V. A. Orru Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6096-6099
Diversity‐oriented synthesis : The multicomponent reaction of α‐isocyano amides, aldehydes or ketones, and amines affords N‐(cyanomethyl)amides, presenting the fourth class of products from this combination of reagents (see scheme). The scope of the reaction is very broad and various functional groups are tolerated. The outcome of the reaction can also be directed to the formation of 2H‐2‐imidazolines by AgI catalysis.
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Rik P. Megens Tieme A. van den Berg Dr. A. Dowine de Bruijn Ben L. Feringa Prof. Dr. Gerard Roelfes Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(7):1723-1733
Bleomycin mimics : Efficient oxidative double‐strand DNA cleavage has been achieved with multinuclear non‐heme iron complexes (see scheme). These complexes therefore represent model compounds that mimic the mode of action of the anti‐tumor drug bleomycin.
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Eunji Lee Jung‐Keun Kim Myongsoo Lee Prof. 《Angewandte Chemie (International ed. in English)》2009,48(20):3657-3660
Deep‐water scrolls: It is demonstrated that amphiphilic rods containing lateral flexible chains self‐assemble into two‐dimensional sheets in aqueous solution (see picture). Remarkably, the sheets roll up reversibly into tubular scrolls upon heating, as confirmed by cryo‐transmission electron microscopy and fluorescence microscopy.