Hydrochloric Acid → 10-methyl-5H-[1,2,4]triazolo[1,5-d][1,4]benzodiazepin-6(7H)-one

Participants

Reaction Conditions

Reaction Steps

5. 62.1 g of 5-(chloromethyl)-9-methyl-1,2,4-triazolo[4,3-c]quinazoline are suspended in 1.1 l of dioxan and cooled to 8° C. 320 ml of 1N sodium hydroxide solution are added dropwise thereto within 10 min. at 7° to 10° C. The mixture is stirred at room temperature for 24 h. The reaction mixture is then made weakly acid (pH 5-6) with 2N hydrochloric acid and concentrated in a vacuum. The residue is dissolved in dichloromethane and washed with sodium chloride solution. The organic phase is dried, decolorized with Norit charcoal, filtered clear and concentrated in a vacuum to a volume of about 400 ml. After the addition of 400 ml of ethyl acetate the mixture is again concentrated to a volume of about 200 ml. The crystal slurry is left to stand at -25° C. overnight and the crystals are then filtered off. After drying in a vacuum there are obtained 35.5 g of 10-methyl-5H-[1,2,4]triazolo[1,5-d][1,4]benzodiazepin-6(7H)-one of m.p. 206°-208° C.

Provenance & Evidence