One‐Pot Access to Tetrasubstituted 2‐Aminothiophenes via Regio‐ and Chemoselective Domino Reactions of Dithioesters with Fumaronitrile at Room Temperature

Abstract

AbstractHerein, we report a one‐pot viable protocol to synthesize tetrasubstituted 2‐aminothiophenes engaging readily accessible α‐enolic dithioesters and abundant fumaronitrile under transition metal‐free conditions at room temperature in open air. The reaction proceeds via successive Michael‐type addition/intramolecular cyclization/isomerization cascades. The added features are benign conditions, exclusive regio‐ and chemoselectivity, excellent atom‐/step‐economy, easy purification, and tolerance of wide range of functional groups of a diverse electronic and steric nature. This protocol not only provided a robust and modular approach to various 2‐aminothiophenes in moderate to excellent yields, but also demonstrated the potential of dithioesters and fumaronitrile in the challenging intermolecular cross‐coupling reactions widening the arsenal of synthetic methods.