TMEDA-catalyzed synthesis of pentasubstituted 2-aminopyrroles from ynehydrazides and dialkyl acetylenedicarboxylates

Abstract

Herein, we report a mild and highly atom-economical synthesis of pentasubstituted 2-aminopyrroles from ynehydrazides and dialkyl acetylenedicarboxylates under ambient conditions. This transformation proceeds through a tandem sequence that combines conjugate addition, 3,4-diaza Cope rearrangement and 5-exo-dig cyclization, providing a rapid and modular route to the target scaffolds in moderate to high yields. Furthermore, an integrated approach for the direct conversion of simple terminal alkynes into the target pyrroles was devised, facilitating efficient access to these complex structures.