Hydrochloric Acid → HCID 14015025, compound

Participants

Reaction Conditions

Reaction Steps

Methyl chloroformate (55 g, 0.58 mol) was added to a stirred solution of 2-amino-4-oxo-4,5-dihydrothiophene-3-carbonitrile (68 g, 0.49 mol) and triethylamine (147 g, 1.45 mol) in dichloromethane (1000 ml) at 0° C. After the addition, the mixture was warmed to 25° C. and stirred overnight. The reaction was treated with dichloromethane-methanol (20:1, 2000 mL) and 2N hydrochloric acid (1500 mL). The resulting mixture was filtered and the resulting solid was further extracted with dichloromethane-methanol (20:1, 1500 mL×3). The combined organic extracts were dried over sodium sulfate and concentrated to give a brown solid. The solid was washed with tert-butyl methyl ether (1500 mL) and dried under vacuum to give crude methyl 3-cyano-4-methylthiophen-2-ylcarbamate (160 g) as a brown solid, which was used in next step without purification.

Provenance & Evidence