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Wim L. Noorduin Bernard Kaptein Dr. Hugo Meekes Dr. Willem J. P. van Enckevort Dr. Richard M. Kellogg Prof. Dr. Elias Vlieg Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(25):4581-4583
Grind and cure: Using the nonsteroidal anti‐inflammatory drug naproxen, a novel concept is demonstrated to dramatically enhance the rate of the recently discovered process of deracemization using abrasive grinding. The process relies on a gradual feed of the racemic target material by an in situ conversion.
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Konstantinos D. Vogiatzis Andreas Mavrandonakis Dr. Wim Klopper Prof. George E. Froudakis Prof. 《Chemphyschem》2009,10(2):374-383
In the garden of dispersion: High‐accuracy ab initio calculations are performed to determine the nature of the interactions and the most favorable geometries between CO2 and heteroaromatic molecules containing nitrogen (see figure). Dispersion forces play a key role in the stabilization of the dimer, because correlation effects represent about 50 % of the total interaction energy.
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Benito Alcaide Prof. Dr. Pedro Almendros Dr. Rocío Carrascosa Dipl.‐Chem. Teresa Martínez del Campo Dipl.‐Chem. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(11):2496-2499
Positive discrimination : Chemo‐ and regioselective palladium‐catalyzed cycloetherification of allendiols, namely β,γ‐ and γ,δ‐allendiols, may occur by judicious choice of palladium‐catalyzed conditions owing to their potential ability to discriminate between both nucleophilic sites (see scheme).
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Christian Gnamm Dipl.‐Chem. Caroline M. Krauter Kerstin Brödner Günter Helmchen Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(9):2050-2054
Pressing the configurational switch : Use of enantiomeric Ir catalysts allows the vinylpiperidine building blocks 2 a and 2 b to be synthesized with high selectivity. Total syntheses of the dendrobate alkaloid (+)‐241 D, its C6‐epimer, and a spruce alkaloid are presented as applications.
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Soyoung Jung Won Cho Hee Jung Lee Moonhyun Oh Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(8):1459-1462
This template will self‐destruct : A unique particle‐growth mechanism involves growth of new coordination polymers on the surface of initially formed hexagonal blocks and concomitant dissolution of the blocks to form hexagonal tubes (see scheme and scanning electron, optical, and fluorescence microscopy images). Calcination of the tubes yields ZnO particles of the same shape.
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Jie Han Dr. Xiao‐Yong Chang Li‐Rong Zhu Mei‐Li Pang Dr. Ji‐Ben Meng Prof. Stephen Sin‐Yin Chui Dr. Siu‐Wai Lai Dr. V. A. L. Roy Dr. 《化学:亚洲杂志》2009,4(7):1099-1107
Chain change : Variations in the position, number, and chain length of the n‐alkoxy chains readily tune the liquid‐crystalline properties of 2,5‐diaryl‐1,3,4‐thiadiazole derivatives from smectic to hexagonal columnar mesophases at room temperature. The calamitic S‐heterocyclic compounds show electrical conductivity in both solid and liquid‐crystal states.
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Mauri A. Kostiainen Dr. Henna Rosilo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(23):5656-5660
Losing the grip : The synthesis of multivalent low‐molecular‐weight dendrons with lysine branching units coupled to disulfide‐linked spermine surface groups is described. It is furthermore demonstrated that the dendrons bind DNA with good affinity (see image), but are also able to release the DNA in a reductive environment.
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Thomas M. Gøgsig Anders T. Lindhardt Dr. Mouloud Dekhane Dr. Julie Grouleff Troels Skrydstrup Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(24):5950-5955
Easy and direct : Regioselective Mizoroki–Heck‐coupling reactions using heteroaromatic tosylates as electrophiles were achieved, thus providing direct and easy access to highly functionalized α‐heteroarylvinyl amides and ethers.
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Fabien Mançois Jean‐Luc Pozzo Prof. Jianfeng Pan Dr. Frédéric Adamietz Vincent Rodriguez Prof. Laurent Ducasse Dr. Frédéric Castet Dr. Aurélie Plaquet Benoît Champagne Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(11):2560-2571
Molecular switches : Highly efficient acido‐ and photoswitchable frequency doublers (see scheme) based on the indolinooxazolidine core are studied by means of hyper‐Rayleigh experiments and quantum‐chemical calculations.
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Maj‐Britt Suhr Kirketerp Michael Åxman Petersen Dr. Marius Wanko Dr. Leonardo Andres Espinosa Leal Henning Zettergren Dr. Françisco M. Raymo Prof. Angel Rubio Prof. Mogens Brøndsted Nielsen Prof. Steen Brøndsted Nielsen Prof. 《Chemphyschem》2009,10(8):1207-1209
From blue to red: While four π‐conjugated nitrophenolates absorb within a relatively narrow region in solution, they cover the entire visible spectrum when isolated in vacuo (see picture). The work combines gas‐ and solution‐phase spectroscopy and provides the first benchmark of theoretical excitation energies for nitrophenolates.
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Ana Escribano‐Cuesta Verónica López‐Carrillo Dominic Janssen Dr. Antonio M. Echavarren Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(23):5646-5650
Gold and rings : The gold(I)‐catalyzed addition of aldehydes to 1,6‐enynes gives 1,3‐dienes, by a cycloaddition/fragmentation process. 1,5‐Enynes react with aldehydes and ketones by the 5‐endo‐dig pathway to give the corresponding cycloadducts.
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Claire Kammerer Guillaume Prestat Dr. David Madec Dr. Giovanni Poli Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4224-4227
Free to decide : Various 4‐(α‐styryl) γ‐lactams are synthesized in 61–88 % yield by a phosphine‐free palladium‐catalyzed carbopalladation/allylic alkylation domino sequence (see scheme). The cyclization is totally regio‐ and diastereoselective in favor of the 3,4‐trans‐disubstituted γ‐lactam. The process is successfully applied to the synthesis of a new aza analogue of the naturally occurring lignan (+)‐oxo‐parabenzlactone.
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Donghua H. Zhou Dr. Gautam Shah Charles Mullen Dennis Sandoz Chad M. Rienstra Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1253-1256
The natural way : A sensitive NMR spectroscopic method is developed to obtain well‐resolved two‐dimensional spectra (15N–1H and 13C–1H) for natural‐abundance (that is, without the need for isotopic enrichment) large‐molecule samples, such as biopharmaceuticals. This method gives structural insights on two lyophilized aprotinin samples and three insulin samples in lyophilized, microcrystalline suspension formulation (red; see picture) and fibril (green) forms.
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Philipp Selig Dr. Eberhardt Herdtweck Dr. Thorsten Bach Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3509-3525
The stereogenic centers at C3 and C12 of meloscine ( 3 ) can be established in the photochemical key step 1 → 2 . 1,2‐retro‐Benzilic acid rearrangement to a five‐membered ring, reductive amination, Claisen rearrangement, and ring‐closing metathesis are further key steps in the transformation of cyclobutane 2 into the target molecule 3 (14 steps, 9 % overall yield). Enantioselective access to (+)‐meloscine was possible when the [2+2]‐photocycloaddition was conducted in the presence of a chiral template.