Abstract

An N-heterocyclic carbene (NHC)-catalyzed asymmetric [4+2] annulation of (E)-2-benzoyl-3-phenylacrylonitriles with α-chloroaldehydes has been developed. The protocol leads to 5-cyano-substituted dihydropyranones in good to excellent yields with excellent diastereo- and enantioselectivities (up to 93% yield, >20:1 d.r. and 99% ee).

An N-heterocyclic carbene (NHC)-catalyzed asymmetric [4+2] annulation of (E)-2-benzoyl-3-phenylacrylonitriles with α-chloroaldehydes has been developed. The protocol leads to 5-cyano-substituted dihydropyranones in good to excellent yields with excellent diastereo- and enantioselectivities (up to 93% yield, >20:1 d.r. and 99% ee).

中文翻译：

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N-杂环碳烯催化的α-氯醛活化：5-氰基取代的二氢吡喃酮的不对称合成

摘要

已开发出一种由N-杂环卡宾（NHC）催化的（E）-2-苯甲酰基-3-苯基丙烯腈与α-氯醛的不对称[4 + 2]环合反应。该方案导致5-氰基取代的二氢吡喃酮具有良好的产率至优异的非对映选择性和对映选择性（高达93％的产率，> 20：1 dr和99％的ee）。

已开发出一种由N-杂环卡宾（NHC）催化的（E）-2-苯甲酰基-3-苯基丙烯腈与α-氯醛的不对称[4 + 2]环合反应。该方案导致5-氰基取代的二氢吡喃酮具有良好的产率至优异的非对映选择性和对映选择性（高达93％的产率，> 20：1 dr和99％的ee）。