The first cobalt-catalyzed asymmetric Kumada cross-coupling with high enantioselectivity has been developed. The reaction affords a unique strategy for the enantioselective arylation of α-bromo esters catalyzed by a cobalt-bisoxazoline complex. A variety of chiral α-arylalkanoic esters were prepared in excellent enantioselectivity and yield (up to 97% ee and 96% yield). The arylated products were transformed
Addition of Grignard Reagents to Aryl Acid Chlorides: An Efficient Synthesis of Aryl Ketones
作者:Xiao-jun Wang、Li Zhang、Xiufeng Sun、Yibo Xu、Dhileepkumar Krishnamurthy、Chris H. Senanayake
DOI:10.1021/ol052150q
日期:2005.12.1
addition of Grignardreagents to acid chlorides in the presence of bis[2-(N,N-dimethylamino)ethyl] ether proceeds selectively to provide aryl ketones in high yields. A possible tridentate interaction between Grignardreagents and bis[2-(N,N-dimethylamino)ethyl] ether moderates the reactivity of Grignardreagents, preventing the newly formed ketones from nucleophilic addition by Grignardreagents.