Trifluoroacetic anhydride → HCID 22914601, compound

Participants

Reaction Steps

8.7 ml (62.9 mmol) of trifluoroacetic anhydride were added dropwise at 5°-8° to a suspension of 15 g (57.2 mmol) of 5-methyl-4-oxo-5,6-dihydro-4H-imidazo[1,5-a]thieno[3,2-f][1,4]diazepine-7-carboxamide in 80 ml of dioxan and 20 ml of pyridine. The beige solution obtained was stirred at 50° for 2.5 hours and subsequently poured into 220 ml of ice-water. The resulting precipitate was filtered off. After drying at 70°/10 Torr there were obtained 12.70 g (91%) of 5-methyl-4-oxo-5,6-dihydro-4H-imidazo[1,5-a]thieno[3,2-f][1,4]diazepine-7-carbonitrile as a white powder of m.p. 197°-200°.

Provenance & Evidence