4-Bromoaniline → 1-[(4-bromo-phenylimino)-ethoxycarbonylamino-methyl]-1H-pyrazole-4-carboxylic acid ethyl ester

Participants

Reaction Steps

Ethyl isothiocyanatoformate (1.44 mL, 12.2 mmol) was added to a solution of 4-bromo-phenylamine (1.91 g, 11.1 mmol) and DCM (37 mL). After 1 h, triethylamine (4.65 mL, 33.4 mmol) was added to the reaction mixture, followed by ethyl pyrazole-4-carboxylate (1.87 g, 13.3 mmol), and EDCl (3.20 g, 16.7 mmol). After 18 h, the reaction mixture was diluted with DCM (150 mL), washed with brine (50 mL), dried (MgSO4), and concentrated. The residue was purified by FCC (5-40% EtOAc/hexanes) to yield the titled compound (1.84 g, 40% yield). MS (ESI/Cl): mass calcd. for C16H17BrN4O4, 408.1; m/z found, 409.1 [M+H]+.

Provenance & Evidence