Ethyl Acetate → (R)-(-)-2-oxo-3-tert-butoxycarbonylamino-5-phenyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine

Participants

Reaction Conditions

Reaction Steps

To a solution of 5 g of (R)-(+)-2-oxo-3-tert-butoxycarbonylamino-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine in 25 ml of cyclohexanone were added 5.96 g of cyclooctene and 0.5 g of 10% palladium carbon. The mixture was stirred at the internal temperature of 145° C. for 2.5 hours. After the reaction mixture was cooled to room temperature, 20 ml of ethyl acetate was added. The mixture was filtered and the filtrate was concentrated under reduced pressure. The residue was crystallized by adding thereto diisopropyl ether and n-hexane and the resulting crystals were collected by filtration, whereby 3.2 g of the title compound was obtained.

Provenance & Evidence