(R)-2-((tert-Butoxycarbonyl)amino)-3-((2-nitrophenyl)amino)propanoic acid → (R)-2-oxo-3-tert-butoxycarbonylamino-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine

Participants

Reaction Steps

10% palladium carbon (1 g) was added to a solution of (R)-(−)-2-tert-butoxycarbonylamino-3-(2-nitrophenylamino)propionic acid (7.6 g) in tetrahydrofuran (100 ml), and the mixture was stirred under hydrogen atmosphere at room temperature for 3 hours. The reaction mixture was filtrated, and the filtrate was concentrated under reduced pressure, to thereby obtain (R)-2-tert-butoxycarbonylamino-3-(2-aminophenylamino)propionic acid. The residue was dissolved in toluene (100 ml), the solution was refluxed overnight. After allowed to cool, the reaction mixture was concentrated under reduced pressure, the residue was purified by silica gel column chromatography(ethyl acetate:n-hexane=1:1), to thereby obtain 5.16 g of the title compound (Yield 80%).

Provenance & Evidence