To a mixture of 3-methoxy-4-(4-methyl-1H-imidazol-1-yl)benzoic acid (12.1 g) and tert-butyl hydrazinecarboxylate (7.61 g) in DMF (100 mL) was added diethyl phosphoryl cyanide (8.55 mL) at room temperature. After stirring at room temperature for 30 min, triethylamine (21.6 mL) was added, and the mixture was stirred overnight. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was washed with water and saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (8.00 g).
