1,1'-Carbonyldiimidazole → Tert-butyl 2-[(4-{2-[2-(acetylamino)-1,3-thiazol-4-yl]ethyl}benzyl)carbamoyl]hydrazinecarboxylate

Participants

Reaction Steps

To a suspension of 1,1′-carbonyldiimidazole (332.1 mg, 2.048 mmol) in anhydrous tetrahydrofuran (1.3 ml) was added tert-butyl carbazate (270.7 mg, 2.048 mmol). After stirring at room temperature for 15 min, N-(4-{2-[4-(aminomethyl)phenyl]ethyl}-1,3-thiazol-2-yl)acetamide (282.6 mg, 1.024 mmol) was added, and the mixture was stirred at room temperature for 6 hr and concentrated under reduced pressure. Ethyl acetate and water were added to the residue, and the mixture was stirred, stood still and then partitioned. The aqueous layer was extracted with ethyl acetate, and the combined organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (FUJI SILYSIA CHEMICAL LTD. BW-300SP 24 g, dichloromethane:methanol=30:1→20:1). The residue was further purified by silica gel column chromatography (FUJI SILYSIA CHEMICAL LTD. DM-2035 16 g, dichloromethane:methanol=30:1) to give tert-butyl 2-[(4-{2-[2-(acetylamino)-1,3-thiazol-4-yl]ethyl}benzyl)carbamoyl]hydrazinecarboxylate (348.3 mg, 0.803 mmol, yield 78.5%) as a white solid.

Provenance & Evidence