反应详情

5-p-Methoxybenzylidene hydantoin, 171.5 g., in 680 ml. of water, 63 g. of 50% sodium hydroxide solution and 6 g. of 20% palladium-on-carbon is shaken under a hydrogen atmosphere at a pressure of 51.5 psi. for about one and a half hours until the hydrogen pressure no longer diminishes. The reaction is vented and the mixture filtered to separate the catalyst. The filtrate is cooled and taken to pH 2 with concentrated hydrochloric acid. The solid is separated by filtration, washed with water and dried at 50° C. in a vacuum oven yielding the above named compound, mp. 177°-179° C.

1. filtrationthe mixture filtered
2. customto separate the catalyst
3. temperatureThe filtrate is cooled
4. customThe solid is separated by filtration
5. washwashed with water
6. customdried at 50° C. in a vacuum oven
7. customyielding the