Facile synthesis of 5α-functionalized pyrroles via multicomponent reactions of vicinal tricarbonyl compounds, enamines, and nucleophiles

Abstract

Pyrrole is a versatile heterocyclic moiety that is widely used in many areas, while methods for the direct synthesis of α-functionalized pyrroles are still limited. We report herein novel B(C₆F₅)₃-catalyzed multicomponent reactions of vicinal tricarbonyl compounds (VTCs), enamines, and nucleophiles, providing a simple and universal method to synthesize highly functionalized pyrroles in which a diverse range of functional groups can be easily installed at the 5α position. The enamines used can be formed in situ via reactions of amines with alkynes, allenes, or enaminones to greatly expand the applications of vicinal tricarbonyl compounds.