反应详情

A solution of 8.00 g. of N-[(3-trifluoromethyl-4-chloro-phenyl)-carbamoyl]-2-methylalanine methyl ester in 20 ml. of 6-N aqueous hydrochloric acid and 20 ml. of acetone are warmed on a steam bath for 2 hours and the mixture is then concentrated. The product which has precipitated is first recrystallized from methylene chloride and then from methylene chloride/petroleum ether. After drying under greatly reduced pressure at 50° for 20 hours, 3-(3-trifluoromethyl-4-chloro-phenyl)-5,5-dimethylhydantoin of melting point 152°-153° is obtained.

1. concentrationthe mixture is then concentrated
2. customThe product which has precipitated
3. customis first recrystallized from methylene chloride
4. customAfter drying under greatly reduced pressure at 50° for 20 hours