Sodium Hydroxide → rac-7-amino-5-(o-chlorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one

Participants

Reaction Steps

108.9 g (0.316 mol) of rac-5-(o-chlorophenyl)-1,3-dihydro-1,3-dimethyl-7-nitro-2H-1,4-benzodiazepin-2-one are dissolved in 750 ml of concentrated hydrochloric acid. 215 g (0.95 mol) of stannous chloride are added portionwise to the solution while cooling with ice and stirring and the mixture is stirred at room temperature for 3 hours. The mixture is subsequently neutralised at 0° C. with 10 N sodium hydroxide and the aqueous phase is extracted with methylene chloride/ethanol (4:1). The organic phase is washed with water, dried and evaporated. Recrystallisation of the residue from ethyl acetate/petroleum ether yields rac-7-amino-5-(o-chlorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one of melting point 180° C.

Provenance & Evidence