To a solution of 2-(4-chlorophenylamino)-2-phenylacetic acid (I11) (574 mg, 2.20 mmol) in dry THF (20 ml), were added DCC (543 mg, 2.64 mmol), HOBt (359 mg, 2.64 mmol), and 3(R)-quinuclidinol (558 mg, 4.40 mmol). The resulting mixture was stirred at RT overnight (UPLC-MS monitoring: complete conversion). The solvent was evaporated, and the residue was partitioned between EtOAc and 2M K2CO3. The organic phase was dried over Na2SO4, filtered and evaporated to dryness. The resulting crude was purified by flash chromatography (DCM/MeOH=99/1 to 85/15) to obtain the title compound (306 mg, 37% yield, mixture of diastereomers).
