反应详情

53 g (0.54 mol) of phosgene are passed into 61 g (0.5 mol) of 4-methyl-1,2-diaminobenzene in 450 ml of water and the pH is simultaneously kept constant at 7.2 with 86 g (1.08 mol) of 50% strength aqueous sodium hydroxide solution. After cooling, 72 g of precipitated 5-methyl-benzimidazol-2-one of melting point 290° C. are obtained, which corresponds to a yield of 97% of theory.

1. temperatureAfter cooling