1,1'-Thiocarbonyldiimidazole → 3-[Boc(methyl)amino]pyrrolidine-1-carbothioamide

Participants

Reaction Steps

To a stirring solution of thiocarbonyldiimidazole (1.23 g, 6.91 mmol) in THF (10 mL) under N2 was added methylpyrrolidin-3-yl-carbamic acid tert-butyl ester (1.20 g, 5.99 mmol) in THF (7 mL). The reaction mixture was stirred at room temperature of 1 h, and then at 55° C. for 2 h. The reaction was cooled to room temperature, and most (˜14 mL) of THF was removed. The reaction was transferred to a sealable reaction tube, 2N ammonia in methanol (6 mL) was added, and the reaction was stirred at room temperature overnight. Another portion of 2N ammonia in methanol (6 mL) was added, and the reaction was heated to 45° C. for 8 h. The reaction was concentrated to ˜5 mL, and diethyl ether was added to precipitate product. The product was filtered, washed with diethyl ether, and dried to obtain 0.920 g (64.9%) of pure methyl-(1-thiocarbamoyl-pyrrolidin-3-yl)-carbamic acid tert-butyl ester (132) as a white solid.

Provenance & Evidence