反应详情

To a stirred mixture, under nitrogen, of 72.3 g of phenylhydrazine hydrochloride in 600 ml of pyridine, cooled in an ice bath, was added, dropwise, 97.1 g of 2,4-difluorobenzoyl chloride, such that the reaction temperature did not exceed 15° C. The reaction mixture was stirred at ambient temperature for about 16 hours. Dilution of the mixture with water formed a precipitate which was collected, dried, and recrystallized from ethyl acetate to yield 98 g (79%) of 2,4-difluorobenzoic acid, 2-phenylhydrazide. Subsequent recrystallization from ethyl acetate afforded the analytical sample, m.p. 171°-173° C.

1. additionwas added
2. customdid not exceed 15° C
3. customwas collected
4. customdried
5. customrecrystallized from ethyl acetate