Potassium Carbonate → (R)-(-)-1-tert-butylcarbonylmethyl-2-oxo-3-phenoxycarbonylamino-5-cyclohexyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine

Participants

Reaction Steps

To a suspension of 8.9 g of (R)-(−)-1-tert-butylcarbonylmethyl-2-oxo-3-amino-5-cyclohexyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine oxalate in 45 ml of ethyl acetate was added 45 ml of an aqueous solution of 8.25 g of potassium carbonate under ice cooling. The mixture was stirred at the same temperature for 30 minutes. After addition of 3.12 g of phenyl chlorocarbonate under ice cooling, the mixture was stirred for 5 minutes under ice cooling and then at room temperature for 30 minutes. The reaction mixture was then separated into layers. The aqueous layer was extracted with ethyl acetate and the organic layer thus obtained was combined with the organic layer obtained in advance. The combined organic layer was washed with brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure, whereby 9.19 g of the title compound was obtained.

Provenance & Evidence