反应详情

3-(3,5-dichloro-4-phenyl)-5,5-dimethylhydantoin, which melts at 175°-176°, is obtained in the manner indicated in Example 1 from 3,5-dichloro-4-fluoro-aniline and 2-isocyanato-2-methylpropionic acid methyl ester and after crystallizing from ether/petroleum ether. The N-[(3,5-dichloro-4-fluorophenyl)-carbamoyl]-2-methylalanine methyl ester intermediately formed is not isolated.

1. customafter crystallizing from ether/petroleum ether