The visible-light-induced acylation/cyclization of alkynoates with acyl oximes for the construction of 3-acylcoumarins
作者:Quan Zhou、Fang-Ting Xiong、Pu Chen、Bi-Quan Xiong、Ke-Wen Tang、Yu Liu
DOI:10.1039/d1ob01568k
日期:——
by the visible-light-induced acylation/cyclization of alkynoates with various acyl oximecompounds in acetonitrile. The difunctionalization of carbon–carbon triple bonds precedes the generation of iminyl radicals, which is followed by the formation of acyl radicals. The acyl radicals then attack the carbon–carbon triple bonds, followed by 5-exo-trig cyclization and 1,2-ester migration. This strategy
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
Photoinduced Generation of Acyl Radicals from Simple Aldehydes, Access to 3-Acyl-4-arylcoumarin Derivatives, and Evaluation of Their Antiandrogenic Activities
construct the 3-acyl-4-arylcoumarin framework from simple aldehyde with ynoate is described. The reaction proceeded through an acyl radical intermediate generated by hydrogen atom abstraction from aldehyde, followed by reaction with ynoate and then cyclization to afford coumarins. This valuable radical cyclization reaction gave over 20 coumarin derivatives in moderate to good yields with inexpensive 2-tBu-anthraquinone
A new and efficient metal-free tandem acylation/cyclization of alkynoates with aldehydes was developed for the synthesis of 3-acyl-4-arylcoumarins. The reaction was achieved by the addition of acyl radical to alkynes and a C-H bond functionalization to form two new C-C bonds simultaneously.