Hydrochloric Acid → (S)-8-bromo-9-oxo-12,12a-dihydro-9H,11H-azeto[2,1-c]imidazo[1,5-a][1,4]benzodiazepine-1-carboxylic acid

Participants

Reaction Steps

21.8 g (57.9 mmol) of ethyl (S)-8-bromo-9-oxo-12,12a-dihydro-9H,11H-azeto [2,1-c]imidazo [1,5-a][1,4]benzodiazepine-1-carboxylate were heated to reflux for 15 minutes with 17 ml of 4N sodium hydroxide solution and 200 ml of ethanol. 17 ml of 4N hydrochloric acid and 250 ml of water were added at room temperature. The alcohol was evaporated and the suspension was cooled to 0°. By suction filtration and drying the crystals there were obtained 19.8 g (98%) of (S)-8-bromo-9-oxo-12,12a-dihydro-9H,11H-azeto[2,1-c]imidazo[1,5-a][1,4]-benzodiazepine-1-carboxylic acid of m.p. 178°-180°.

Provenance & Evidence