Phenethyl bromide → 3-(R)-(+)-(1-cyano-1,1-diphenylmethyl)-1-phenethylpiperidine

Participants

Reaction Steps

A mixture containing 3-(R)-(+)-(1-cyano-1,1-diphenylmethyl)-piperidine (1 g), phenethyl bromide (0.67 g), anhydrous potassium carbonate (1.5 g) and acetonitrile (25 ml) was heated under reflux for 4 hours. The mixture was partitioned between dichloromethane (50 ml) and 10% aqueous potassium carbonate (30 ml), the layers separated, and the aqueous layer extracted with dichloromethane (3×30 ml). The combined dichloromethane extracts were dried (MgSO4) and concentrated in vacuo to give an oil which was purified by column chromatography on silica eluting with hexane containing dichloromethane (30% up to 70%) then dichloromethane containing methanol (0% up to 5%). The product-containing fractions were combined and concentrated in vacuo to give an oil which was crystallised from acetonitrile to give the title compound as colourless rhombs, yield 0.72 g, m.p. 134-138° C., [α]D25 +13.3° (c 1.0, CH2Cl2).

Provenance & Evidence