Sodium Bicarbonate → 4-(1-Methylcyclopropan-1-yl)piperazine-1-carboxylic acid benzyl ester

Participants

Reaction Steps

Bis-(2-oxoethyl)carbamicacidbenzylester (0.90 g, 3.81 mmol) and 1-methyl-cyclopropylamine (0.41 g, 3.81 mmol) were dissolved in dichloroethane (20 mL), and sodium triacetoxyborohydride (3.23 g, 15.24 mmol) was added thereto. The mixture was stirred for 4 days at room temperature. A saturated aqueous solution of sodium hydrogen carbonate (20 mL) was added to the reaction liquor, and the mixture was stirred for 20 minutes, and then extracted with methylene chloride. The extract was washed with saturated brine, and dried over anhydrous sodium sulfate, and then the solvent was concentrated under reduced pressure. The obtained residue was purified by flash chromatography (Flash Chromatography System from Biotage AB, column size: 25S, n-hexane/ethyl acetate=5/1 to ethyl acetate), to obtain the title compound (509 mg, 49%) as an oily matter.

Provenance & Evidence