Construction of Thienopyrroles through Rhodium-Catalyzed Direct Annulation of (Acetylamino)thiophenes with Alkynes

Abstract

The direct annulative coupling of 3-(acetylamino)thiophenes with internal alkynes proceeds smoothly under rhodium catalysis through acetylamino-directed C-H bond cleavage at the C2-position to lead to the effective construction of 4-acetylthieno[3,2-b]pyrrole derivatives. The acetyl directing group on the annulation product is readily removable to produce 4-unprotected thieno[3,2-b]pyrrole derivative.