Ammonia → Nordiazepam

Participants

Reaction Steps

A mixture of ethanol (1100 ml), hexamethylenetetramine (70.0 g., 0.5 mol), 26% ammonium hydroxide (58 ml) and 2-chloroacetamido-5-chlorobenzophenone (308.2 g., 1.0 mol) was stirred and slowly heated to reflux with ammonia bubbling into the mixture. Reflux was continued for 5 hours, the flow of ammonia was interrupted, and the reaction mixture distilled to dryness in vacuo. The residue was heated to reflux for 30 minutes in a mixture of toluene (500 mls) and water (500 mls) and then allowed to cool slowly to room temperature. The crystalline material was filtered, washed with toluene (100 mls) and hot water (2 × 250 mls) and dried to constant weight. The product, 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one (226 g) obtained corresponded to a yield of 83.5%, melting point 210° C.

Provenance & Evidence