Enantioselective Synthesis of N-Phenyl-dihydropyrano[2,3-c]-pyrazoles via Cascade Michael Addition/Thorpe-Ziegler Type Cyclization Catalyzed by a Chiral Squaramide  

作　　者：Junhua Li Daming Du 

机构地区：[1]School of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,China

出　　处：《Chinese Journal of Chemistry》2015年第4期418-424,共7页中国化学（英文版）

基　　金：support from the Na-tional Natural Science Foundation of China(Grant No.21272024).

摘　　要：Enantioselective synthesis of biologically active dihydropyrano[2,3-c]pyrazoles has been achieved through a squaramide-catalysed Michael addition/Thorpe-Ziegler type cyclization cascade reaction between arylidenepyra-zolones and malononitrile.A series of optically active dihydropyano[2,3-c]pyrazoles were obtained in excellent yields(up to 99%)and moderate to good enantioselectivities(up to 79%ee)under mild reaction conditions.

关 键 词：ORGANOCATALYSIS SQUARAMIDE HETEROCYCLES Michael addition CYCLIZATION 

分 类 号：O62[理学—有机化学]