Ammonia → 3-Thiophenecarboxylic acid, 4-(aminosulfonyl)-, methyl ester

Participants

Reaction Conditions

Reaction Steps

Methyl 4-(chlorosulfonyl)thiophene-3-carboxylate (5 g, 20.75 mmol) was dissolved in methylene chloride (50 mL), the solution was cooled to 0° C., and ammonia gas (1.1 g, 64.7 mmol) was introduced during 20 min. After a further 2 h of stirring, the reaction mixture was washed to neutrality with 10% aqueous hydrochloric acid and then with brine. After concentration os the solvent, crude methyl 4-sulfamoylthiophene-3-carboxylate was obtained which was recrystallized from ethanol to yield 2.7 g of methyl 4-sulfamoylthiophene-3-carboxylate. MS: 220 (M−1), 221.9 (M+1), 243.8 (M+Na).

Provenance & Evidence