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Published on: June 21, 2017
Asymmetric Formal Vinylogous Iminium Ion Activation for Vinyl-Substituted Heteroaryl and Aryl Aldehydes
Xin-Yue Gao1, Ru-Jie Yan1, Ben-Xian Xiao1
1Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy , Sichuan University , Chengdu 610041 , China.
Abstract:
The vinyl group tethered to furfurals could be LUMO-lowered by forming formal vinylogous iminium ion intermediates catalyzed by a chiral secondary amine and underwent asymmetric [3 + 2] cycloaddition reactions with N-trifluoroethyl-substituted isatin imines, furnishing a variety of spirooxindoles incorporating a 3,2'-pyrrolidine motif with excellent stereoselectivity. In addition, this strategy has been successfully expanded to a number of vinyl-substituted electron-rich heteroaryl aldehydes and even some specific aryl aldehydes.
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