Ethanol → 7-chloro-5-methyl-6-oxo-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid

Participants

Reaction Steps

A mixture of 3.11 g (9.72 mmol) of ethyl 7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylate, 10 ml of ethanol, 2 ml of water and 400 mg of sodium hydroxide is heated to boiling under reflux for 1 hour. After evaporation of the ethanol, the residue is treated with 10 ml of 1 N hydrochloric acid. The colourless material obtained is filtered off under suction, washed with water and dried. There is obtained 7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid with a decomposition point of 283°-284°.

Provenance & Evidence