2-(4-Fluorophenyl)-2-(piperidin-1-yl)acetic acid hydrochloride (255 mg, 0.93 mmol) was dissolved in dry THF (10 ml) and (R)-quinuclidin-3-ol (355 mg, 2.79 mmol), DCC (384 mg, 1.86 mmol), HOBt (285 mg, 1.86 mmol) were added. The mixture was stirred at room temperature for 16 hours. THF was evaporated and the residue was taken up with EtOAc and washed with sat. NaHCO3, water and brine. The organic phase was dried over Na2SO4, filtered and evaporated. The crude was purified by flash chromatography (DCM/MeOH/NH4OH=98/2/0.2) to obtain (R)-quinuclidin-3-yl 2-(4-fluorophenyl)-2-(piperidin-1-yl)acetate (126 mg, 39.0% yield) as a white solid.
