Triethylamine → 1-(1-tert-butylcarbonylmethyl-2-oxo-5-cyclohexyl-8-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-3-yl)-3-(3-ethoxycarbonylphenyl)urea

Participants

Reaction Steps

Triphosgene (122 mg) was added to a solution of ethyl 3-aminobenzoate (182 mg) in tetrahydrofuran (10 ml) under ice-cooling, triethylamine (98 μl) was added thereto five times (total: 490 μl), the mixture was stirred at room temperature for 5 minutes. A solution of 1-tert-butylcarbonylmethyl-2-oxo-3-amino-5-cyclohexyl-8-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine (393 mg) in anhydrous tetrahydrofuran (5 ml) was added to the mixture under ice-cooling, stirred at room temperature for 30 minutes. Ice-water was added to the reaction mixture, extracted with methylene chloride. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, the solvent was evaporated under reduced pressure, and a mixed solvent of n-hexane and ethyl acetate(n-hexane:ethyl acetate=1:1) was added to the residue for crystallization, collected by filtration, to thereby obtain 380 mg of the title compound.

Provenance & Evidence