反应详情

m-Trifluoromethylacetophenone (74 g, 0.394 mole), ethyl carbazate (43 g, 0.413 mole), and catalytic p-toluenesulfonic acid (20 mg) were refluxed under N2 over a Dean-Stark trap in toluene (1.2 L) until the theoretical amount of water of reaction was removed (7.1 mL, 6 h). The solvent was then removed in vacuo and 2-(1-(3-(trifluoromethyl)phenyl)ethylidene)hydrazinecarboxylic acid ethyl ester (107 g, 100% yield) was obtained as a white solid which was recrystallized from cyclohexane, mp=94°-96° C.

1. customwas removed (7.1 mL, 6 h)
2. customThe solvent was then removed in vacuo