Ethanol → (+/-)-cis-1-[3,5-Bis(trifluoromethyl)benzoyl]-2-(phenylmethyl)-4-[4-(phenylmethyl)-1-piperazinyl]piperidine

Participants

Reaction Steps

Titanium(IV)isopropoxide (16.5 g) was added to a mixture of intermediate 3 (21.5 g) and 1-(phenylmethyl)piperazine (8.81 g) in DCM (35 ml). The mixture was stirred for 3 hours at RT. Sodium cyanoborohydride (2.85 g) and ethanol (70 ml) were added and the resulting reaction mixture was stirred overnight at RT. Water (5 ml) and DCM were added. The biphasic mixture was filtered over dicalite, and the filter residue was washed with DCM. The organic layer was separated, dried, filtered and the solvent was evaporated. The residue was crystallized from CH3CN and the precipitate was filtered off and dried, yielding 7.93 g (26.9%) of (±)-cis-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(phenylmethyl)-4-[4-(phenylmethyl)-1-piperazinyl]piperidine (compound 16; mp. 143.8° C.).

Provenance & Evidence