4-Bromo-2-fluorophenyl isocyanate → 1,1-dimethylethyl (3S)-3-[2-(2-{[(4-bromo-2-fluorophenyl)amino]carbonyl}hydrazino)-2-oxoethyl]-1-pyrrolidinecarboxylate

Participants

Reaction Steps

A solution of 1,1-dimethylethyl (3S)-3-(2-hydrazino-2-oxoethyl)-1-pyrrolidinecarboxylate (6.58 mmol) in dichloromethane (15 mL) was cooled to 0° C. and was treated drop-wise with 4-bromo-2-fluoro-1-isocyanatobenzene (6.58 mmol). The reaction was allowed to warm to room temperature, and after ˜30 min a white solid had formed. The reaction contents were concentrated to dryness in vacuo. No further purification was carried out on the resulting white solid (3.01 grams, 100%). MS(ES)+ m/e 459/461 [M+H]+ (bromide isotope pattern).

Provenance & Evidence