Ammonia → 7-chloro-8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepin-3-carboxamide

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Reaction Steps

19.8 g (0.0639 mol) of 7-chloro-8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid were suspended in 100 ml of N,N-dimethylformamide while gassing with argon and treated portionwise at room temperature with 10.9 g (0.0671 mol) of 1,1'-carbonyldiimidazole. After the CO2 evolution had finished the beige suspension was stirred at 50° for 30 min., cooled and treated dropwise at a temperature below 25° within about 10 min. with 20 ml of 25% ammonia. After stirring for 15 minutes the brownish solution obtained was poured into 600 ml of ice-water. The mixture was stirred at room temperature for 30 min. and filtered, whereupon the crystals were rinsed with a total of 200 ml of water. After drying there were obtained 14.4 g (73%) of 7-chloro-8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxamide as beige crystals; m.p. 292°-294°.

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