6-(4-chlorophenyl)-4-ethyl-1-methyl-4H-benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepin-5(6H)-one → 6-(4-chlorophenyl)-1-methyl-4H-benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepin-5(6H)-one

Participants

Reaction Steps

Into a 50 mL flask evacuated and brimmed with dry nitrogen, was charged with a solution of 6-(4-chlorophenyl)-4-ethyl-1-methyl-4H-benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepin-5(6H)-one (10.0 mg, 0.028 mmol) in tetrahydrofuran (5 mL). To this mixture was added borane-tetrahydrofuran complex solution (1 mol/L, 1 mL) slowly. The mixture was stirred for 12 hours at reflux, quenched by hydrochloric acid aqueous (1.0 mol/L, 1 mL) to adjust pH>7 and extracted with ethyl acetate (5 mL*3). The organic layer was concentrated to give a residue. The residue was purified by prep-HPLC (Phenomenex C18 (150 mm*21.2 mm*5 um), acetonitrile/water=1:100 (0.1% formic acid), flow rate: 30 mL/min) to give 6-(4-chlorophenyl)-1-methyl-4H-benzo[b][1,2,4]triazolo[4,3-d][1,4]diazepin-5(6H)-one as an off-white solid (1.2 mg, 12%).

Provenance & Evidence