共查询到20条相似文献,搜索用时 31 毫秒
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Annemarie Schäfer Dr. Wolfgang Saak Dipl.‐Chem. Detlev Haase Thomas Müller Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(16):3945-3950
Breaking the molecular symmetry by protonation of germylene 1 is the key step in the synthesis of the germyliumylidene 2 , which is stabilized by an intramolecular interaction with a distant imido group.
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Andrey A. Fokin Prof. Dr. Boryslav A. Tkachenko Dr. Natalie A. Fokina Dr. Heike Hausmann Dr. Michael Serafin Dr. Jeremy E. P. Dahl Dr. Robert M. K. Carlson Dr. Peter R. Schreiner Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3851-3862
Functionalized nanodiamonds : Various functional groups have been incorporated into the structures of the naturally occurring diamondoids [1(2)3]tetramantane and [12312]hexamantane (cyclohexamantane), which represent hydrogen‐terminated prism‐shaped nanodiamonds (see picture). The attachment points define the use of these diamond‐like molecules as geometric building blocks for a variety of applications.
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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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Ken Tanaka Prof. Dr. 《化学:亚洲杂志》2009,4(4):508-518
Tying up loose ends : Recent advances towards a development of novel transition‐metal‐catalyzed enantioselective [2+2+2] cycloadditions for the synthesis of biaryls are summarized in this Focus Review. Additionally, the enantioselective synthesis of axially chiral biaryls possessing non‐biaryl axial chirality is also presented. These novel asymmetric aromatization reactions allow the production of various axially chiral biaryl compounds with high enantioselectivity.
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Renata Marcia de Figueiredo Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1190-1193
Diaminations are a girl's best friend : New reactions in the field of transition‐metal‐catalyzed diamination of olefins provide a powerful tool for the elaboration of more complex molecules bearing the 1,2‐diamine moiety. An overview of these methods, including asymmetric versions, is given.
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Toshihide Maki Dr. Shinya Iikawa Gen Mogami Hitomi Harasawa Yoshihiro Matsumura Prof. Dr. Osamu Onomura Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(21):5364-5370
Get selective! A selective oxidation of 1,2‐diols to α‐hydroxyketones catalyzed by organotin compounds has been developed (see scheme). Invaluable chemo‐ and stereoselectivity were found in the reaction. The catalytic system has been achieved by electrochemical and chemical oxidation.
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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.
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Sandro Pagano Giuseppe Montana Claudia Wickleder Prof. Dr. Wolfgang Schnick Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6186-6193
Shine a light with cyanates : A novel approach for the synthesis of urea complexes and homoleptic cyanates of alkaline earth metals and europium is described. The compounds have been fully characterized, including their magnetism and temperature‐dependent luminescence properties (see graphic).
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