4-Bromo-2-fluorophenyl isocyanate → 1,1-dimethylethyl (3S)-3-[2-(2-{[(4-bromo-2-fluorophenyl)amino]carbonyl}hydrazino)-2-oxoethyl]-1-pyrrolidinecarboxylate
Reaction equation
[NH:1]([C:3](=[O:17])[CH2:4][C@@H:5]1[CH2:9][CH2:8][N:7]([C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[CH2:6]1)[NH2:2].[Br:18][C:19]1[CH:24]=[CH:23][C:22]([N:25]=[C:26]=[O:27])=[C:21]([F:28])[CH:20]=1>ClCCl>[Br:18][C:19]1[CH:24]=[CH:23][C:22]([NH:25][C:26]([NH:2][NH:1][C:3](=[O:17])[CH2:4][C@@H:5]2[CH2:9][CH2:8][N:7]([C:10]([O:12][C:13]([CH3:14])([CH3:16])[CH3:15])=[O:11])[CH2:6]2)=[O:27])=[C:21]([F:28])[CH:20]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
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).