酰胺的直接转化:仲酰胺与丹尼谢夫斯基双烯的还原环加成反应

Abstract

酰胺作为稳定的合成中间体被广泛应用于有机合成和药物化学.因此,发展通用、化学选择性的酰胺直接转化的方法十分重要.在本工作中,我们报道仲酰胺与丹尼谢夫斯基双烯的还原环加成反应,用于把仲酰胺直接转化为2-取代-2,3-二氢-4-吡啶酮.该“一瓶反应“包含酰胺通过三氟甲磺酸酐活化、部分还原、和[4+2]环加成反应3个环节.基于这一步骤经济型方法,建立了生物碱(±)-lASubInE I和(±)-MyrTInE的简便、无保护基全合成.

Amides are widely used as stable synthetic intermediates in organic synthesis and medicinal chemistry.Versatile and chemoselective C—C bond forming methods for the direct transformation of amides are highly demanding.In this paper, we report the reductive cycloaddition of common secondary amides with the Danishefsky diene to produce 2-substituted 2,3-dihydro-4-pyridones.This one-pot procedure involves amide activation with triflic anhydride, partial reduction, and [4+2] cycloaddition.The synthetic utility of this step-econimical method was demonstrated by the short and protecting-group-free total syntheses of alkaloids(±)-lasubine I and(±)-myrtine.