3,5-Bis(trifluoromethyl)benzoic acid → tert-butyl (3R*,4R*)-4-({[3,5-bis(trifluoromethyl)phenyl]carbonyl}amino)-3-(3,4-dichlorophenyl)piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of the compound (1.48 g) obtained in step 4, 3,5-bis(trifluoromethyl)benzoic acid (1.10 g) and Et3N (0.40 mL) in acetonitrile (15 mL) were added WSC.HCl (1.10 g) and HOBt (0.88 g), and the mixture was stirred at room temperature for 14 hr. The reaction mixture was poured into water, and the resultant product was extracted with ethyl acetate. The organic layer was washed with saturated aqueous sodium hydrogen carbonate solution and brine and dried, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (solvent gradient; 10→33% ethyl acetate/hexane) to give the title compound (1.65 g, 98%) as a white powder.

Provenance & Evidence