Hydrogen Bromide → 3-Amino-1-isobutyl-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one

Participants

Reaction Steps

A solution of 3-benzyloxycarbonylamino-1-isobutyl-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one (880 mg, 1.99 mmol) in methylene chloride (10 mL) was cooled to 0° C. and saturated with hydrogen bromide gas. The reaction was refluxed overnight, cooled, saturated with hydrogen bromide and refluxed 3 h. Solvent was evaporated and the reaction worked up with saturated sodium bicarbonate solution and methylene chloride. The title compound was isolated by column chromatography (silica gel, 0 to 10% methanol in methylene chloride gradient elution). Enantiomers were separated on a Chiralpak AS column (silica gel, 30% hexane, 70% ethanol with diethylamine, isocratic elution), yielding enantiomer A of the title compound (91.9 mg) and enantiomer B of the title compound (87.1 mg).

Provenance & Evidence