Synthesis of a new pyrrolo[1,3]diazepine: 4H‐pyrrolo[1,2‐a]thieno[2,3‐e][1,3]diazepine

Abstract The 4H‐pyrrolo[1,2‐a]thieno[2,3‐e][1,3]diazepine (20) was synthesized by the one‐pot intramolecular cyclization of the appropriate nitroaldehyde 13. This key intermediate 13 was obtained by two pathways from methyl 3‐bromomethylthiophene‐2‐carboxylate (6).