反应详情

Methyl acrylate (15 g.) was added to a solution of 2-amino-5,6-dimethylbenzimidazole (27.2 g.) in ethanol (100 ml.). After stirring for 2 days at room temperature, the crystalline precipitate which had formed in the reaction mixture was separated by filtration, washed with ethanol and then with ether, to give 7,8-dimethyl-3,4-dihydropyrimido[1,2-a]-benzimidazol-2(1H)-one (37.2 g.), m.p. 322°-323° C.

1. customthe crystalline precipitate which had formed in the reaction mixture
2. customwas separated by filtration
3. washwashed with ethanol