Sodium borohydride → HCID 13039296, compound

Participants

Reaction Steps

A solution of 4.77 g 1-cyclopropylcarbonyl-3-phenyl-4-piperidone in 50 ml of absolute ethanol is cooled to 4° C. and treated dropwise under nitrogen with a solution of 0.74 g of sodium borohydride in 50 ml of absolute ethanol over a 10 minute period, keeping the pot temperature below 10° C. After the addition is complete, the bath is removed. The mixture is cooled while diluting with 100 ml of saturated sodium chloride solution and, after stirring for a few minutes the ethanol is removed in vacuo and the aqueous residue is extracted with dichloromethane (1×150 ml, 2×100 ml). The combined dichloromethane extracts are washed with 150 ml of saturated sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford a yellow oil. The oil is chromatographed on 190 g of silica gel using ether as solvent followed by 5%, 10% and finally 50% acetone/ether mixture. The cis-isomer is eluted first followed by the trans-isomer as a colorless solid. Recrystallization from 5 ml of ethyl acetate affords product as a colorless crystalline solid, mp, 125°-127.5° C.

Provenance & Evidence