反应详情

2,4-difluoroaniline (25g) and 25.2 g of pyridine were dissolved in 200 ml of dichloromethane to which was added dropwise 33.3 g of phenyl chloroformate with ice cooling. After stirring for 30 minutes with ice cooling, the reaction solution was washed with water and dried followed by distilling the solvent to give a mixture of phenyl 2,4-difluorophenylcarbamate and pyridine. To the mixture was added 30.7 g of 2-(di-ethoxy)ethylamine and the mixture was stirred at room temperature. The crystals separated out were filtered and washed with petroleum ether to give 37.8 g of N-(2,2-diethoxyethyl)-N'-(2,4-difluorophenyl)urea as colorless crystals.

1. washthe reaction solution was washed with water
2. customdried
3. distillationby distilling the solvent
4. customto give
5. stirringthe mixture was stirred at room temperature
6. customThe crystals separated out
7. filtrationwere filtered
8. washwashed with petroleum ether