Synthesis of Benzofuran‐fused 1,4‐Dihydropyridines via Bifunctional Squaramide‐catalyzed Formal [4+2] Cycloaddition of Azadienes with Malononitrile

2018/10/04 by Zheng Gu, Bo Wu, Guo‐Fang Jiang +1

paper · doi:10.1002/cjoc.201800330

Abstract

Abstract An efficient bifunctional squaramide‐catalyzed Michael addition/cyclization of azadienes with malononitrile has been successfully developed, providing a facile access to chiral benzofuran‐fused 1,4‐dihydropyridines with excellent yields, wide substrate scope and up to 99% ee. Additionally, this formal [4+2] cycloaddition can be performed in gram scale without noticeable loss of yield and enantioselectivity.

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