Palladium-catalyzed cross-coupling reactions of dimethyl- and diethylzinc with unsaturated organotellurium compounds
摘要:
The cross-coupling reaction of diethyl- or dimethylzinc compounds with disubstituted vinylic tellurides as electrophilic partners is described. These cross-coupling reactions were catalyzed by Pd(PPh3)(4)/CuI and were shown to by general, allowing the formation of a new sp(3)-sp(2) carbon-carbon bond. Good yields and high stereoselectivity were observed in all cases. (C) 2000 Elsevier Science Ltd. All rights reserved.
Carotenoids and related polyenes. Part 4.1 Synthesis of carotenoid analogues containing a conjugated carbonyl group and their fluorescence properties
作者:Yumiko Yamano、Mamoru Mimuro、Masayoshi Ito
DOI:10.1039/a702815f
日期:——
Fluorescence properties of several synthetic carotenoid analogues
have been investigated in order to assess the relationship between
molecular structures and function as a photosynthetic antenna. The
origin of fluorescence is determined by two factors; the length of the
conjugated double bond system and the presence of a carbonyl group. For
efficient energy transfer to chlorophyll a, eight conjugated
double bonds and an associated carbonyl group are required, which
ensures that fluorescence occurs from the S1 state.
Chemo-, Regio-, and Stereoselective Silver-Catalyzed Aziridination of Dienes: Scope, Mechanistic Studies, and Ring-Opening Reactions
作者:Josep Llaveria、Álvaro Beltrán、W. M. C. Sameera、Abel Locati、M. Mar Díaz-Requejo、M. Isabel Matheu、Sergio Castillón、Feliu Maseras、Pedro J. Pérez
DOI:10.1021/ja412547r
日期:2014.4.9
of 2,4-diene-1-ols in a chemo-, regio-, and stereoselective manner to give vinylaziridines in high yields by means of the metal-mediated transfer of NTs (Ts = p-toluensulfonyl) units from PhI═NTs. The preferential aziridination occurs at the double bond neighboring to the hydroxyl end in ca. 9:1 ratios that assessed a very high degree of regioselectivity. The reaction with the silver-based catalysts
LIGANDS FOR NEMATODE NUCLEAR RECEPTORS AND USES THEREOF
申请人:Board of Regents, University of Texas System
公开号:US20130137667A1
公开(公告)日:2013-05-30
An effective anti-nematode methodology entails contacting nematodes with a biologically effective amount of at least one compound according to formula I:
where Q, Q′, R
1
, R
2
, and n are defined herein, or with a stereoisomer, solvate, or pharmaceutically acceptable salt of such compound.
Palladium-catalyzed cross-coupling reactions of dimethyl- and diethylzinc with unsaturated organotellurium compounds
作者:Miguel J Dabdoub、Vânia B Dabdoub、Joseph P Marino
DOI:10.1016/s0040-4039(99)02087-0
日期:2000.1
The cross-coupling reaction of diethyl- or dimethylzinc compounds with disubstituted vinylic tellurides as electrophilic partners is described. These cross-coupling reactions were catalyzed by Pd(PPh3)(4)/CuI and were shown to by general, allowing the formation of a new sp(3)-sp(2) carbon-carbon bond. Good yields and high stereoselectivity were observed in all cases. (C) 2000 Elsevier Science Ltd. All rights reserved.
Synthesis, Structure, and Reactivity of Alkyl-Substituted Half-Sandwich η<sup>5</sup>-Pentadienyl Complexes of Cobalt
作者:Kai E. O. Ylijoki、Ross D. Witherell、Andrew D. Kirk、Sebastian Böcklein、Verner A. Lofstrand、Robert McDonald、Michael J. Ferguson、Jeffrey M. Stryker
DOI:10.1021/om900754h
日期:2009.12.14
Alkyl-substituted η5-pentadienyl complexes of cobalt have been reported to undergo [5 + 2] cycloaddition reactions with alkynes to form substituted η2,η3- and η5-cycloheptadienyl products, providing a new route to the synthesis of substituted cycloheptadienes. A series of cyclopentadienyl and pentamethylcyclopentadienyl cobalt(III) η5-pentadienyl complexes have been prepared, incorporating alkyl and