Triethylamine → 1-(1-cyclohexylcarbonylmethyl-2-oxo-5-cyclohexyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-3-yl)-3-(3-tert-butoxycarbonylphenyl)urea

Participants

Reaction Steps

Triphosgene (122 mg) was added to a solution of tert-butyl 3-aminobenzoate (213 mg) in anhydrous tetrahydrofuran (30 ml) at 0° C., triethylamine (0.49 ml) was added thereto at 0° C. five times each 98 μl over 15 minutes. After the mixture was stirred at room temperature for 5 minutes, a solution of 1-cyclohexylcarbonylmethyl-2-oxo-3-amino-5-cyclohexyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine (395 mg) in anhydrous tetrahydrofuran (10 ml) was added at 0° C., the resultant mixture was stirred at room temperature for one hour. The reaction mixture was concentrated under reduced pressure, and water was added to the residue, extracted with ethyl acetate. The organic layer was washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure, diisopropyl ether was added to the residue for crystallization, collected by filtration, to thereby obtain 570 mg of the title compound (Yield: 92%).

Provenance & Evidence