反应详情

6 ml. of ethyl formate are added to a solution of 1.4 g. (5 mmoles) of 1-methyl-5-phenyl-7-chloro-1,3,4,5-tetrahydro-2H-1,4-benzodiazepine-2-one in 5 ml. of chlorobenzene, and the reaction mixture is maintained at the boiling point of the solvent for 3 hours. Thereafter the solvent is evaporated under reduced pressure, and the oily residue is solidified by treating it with 20 ml. of dry ether. 108 g. (68.6 %) of 1-methyl-4-formyl-5-phenyl-7-chloro-1,3,4,5-tetrahydro-2H-1,4-benzodiazepine-2-one are obtained; m.p.: 167°-169° C. The melting point does not change after recrystallization from ethanol. Rf2 = 0.5.

1. customThereafter the solvent is evaporated under reduced pressure
2. additionby treating it with 20 ml