反应详情

An admixture of 6.65 g (30 mmol) of 4-chloro-3-trifluoromethylphenyl-isocyanate and 4.4 g (30 mmol) of 2-amino-2-ethyl-butyric acid methyl ester were heated to 100° C. and maintained at that temperature for 5 minutes. The resulting crude product, 2-(N-[(4-chloro-3-trifluoromethylphenyl)-carbamoyl]-amino)-2-ethylbutyric acid methyl ester, was heated for 8 hours on a steam bath in a mixture of 200 ml of acetone and 200 ml of 6 N HCl. The mixture was cooled and then extracted with methylene chloride. The extract was dried over sodium sulphate and the methylene chloride was evaporated. The residue was crystallized from petroleum ether and then from methylene chloride/hexane to yield 3-(4-chloro-3-trifluoromethylphenyl)-5,5-diethyl-hydantoin, m.p. 86°-87° C.

1. temperaturemaintained at that temperature for 5 minutes
2. temperatureThe mixture was cooled
3. extractionextracted with methylene chloride
4. dry with materialThe extract was dried over sodium sulphate
5. customthe methylene chloride was evaporated
6. customThe residue was crystallized from petroleum ether