Acetic Anhydride → N,N-Dimethyl-N'-(7-acetoxythieno[2,3-c]pyridine-2-sulfonyl)formamidine

Participants

Reaction Conditions

Reaction Steps

A mixture of N,N-dimethyl-N'-(6-oxido-thieno[2,3-c]pyridine-2-sulfonyl)formamidine (3.5 g, 12.3 mmol) in acetic anhydride (20 ml), under a nitrogen atmosphere, was heated at 120° C. for 3 hours. The dark solution was poured into ice/water and stirred for 1/2 hour. The product was extracted into methylene chloride, washed with sodium carbonate solution, dried over anhydrous sodium sulfate and evaporated to give 4.77 g of crude product. This residue was triturated with methylene chloride/diethyl ether to give 2.0 g (50% yield) of pure product. Recrystallization from ethyl acetate gave product with a broad melting point of 184°-191° C.

Provenance & Evidence