文献类型：期刊文献

英文题名：Heck-type coupling vs. conjugate addition in phosphine-rhodium catalyzed reactions of aryl boronic acids with α,β-unsaturated carbonyl compounds:: a systematic investigation

作者：Zou, Gang; Guo, Jianping; Wang, Zhiyong; Huang, Wen; Tang, Jie

机构：[1]E China Univ Sci & Technol, Adv Mat Lab, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Dept Fine Chem, Shanghai 200237, Peoples R China;[3]E China Normal Univ, Dept Chem, Shanghai 200062, Peoples R China

年份：2007

期号：28

起止页码：3055

外文期刊名：DALTON TRANSACTIONS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000247934100010)】；

语种：英文

摘要：The competition between Heck-type coupling and conjugate addition in phosphine-rhodium catalyzed reactions of aryl boronic acids with alpha,beta-unsaturated carbonyls has been systematically investigated in a toluene-H2O biphasic system. Aside from the intrinsic nature of rhodium and the enolization of carbonyls, the phosphine supporting ligand on rhodium, the ratio of aryl boronic acid to alpha,beta-unsaturated carbonyl and the pH value of the aqueous phase were found to affect the competition significantly. Highly selective rhodium-based catalyst systems have therefore been developed for both Heck-type coupling and conjugate addition by synergistically tuning the supporting ligand, the boronic acid to olefin ratio and other reaction conditions. Conjugate addition with selectivity > 99% and Heck-type coupling with selectivity of up to 100%, 98% and 84% for acrylates, acrylamides and methyl vinyl ketone, respectively, could be achieved in the rhodium-catalyzed reactions of aryl boronic acids with alpha,beta-unsaturated carbonyls using the corresponding optimized rhodium-based catalyst systems.