Silver-Mediated Radical Cyclization of Alkynoates and α-Keto Acids Leading to Coumarins via Cascade Double C–C Bond Formation
作者:Kelu Yan、Daoshan Yang、Wei Wei、Fen Wang、Yuanyuan Shuai、Qiannan Li、Hua Wang
DOI:10.1021/jo502474z
日期:2015.2.6
A novel and convenient silver-mediated radicalcyclization method for the synthesis of coumarin derivatives via the direct difunctionalization of alkynoates with α-keto acids through double C–C bondformation under mild conditions has been developed. This new method is highly efficient and practical, and the starting materials are readily prepared. The present method should provide a useful strategy
A new visible-light-mediated radical cyclization of alkynoates with acyl chlorides is described for the one-pot construction of diverse 3-acylcoumarins with high efficiency and selectivity. This method is successful by sequential difunctionalization of an alkynes CC triple bond with the CCl bonds of acyl chloride and aromatic C(sp2)H bonds. The cyclization is proposed to simultaneously form two new