Quinuclidine-3-carboxylic acid hydrochloride (80 mg, 0.42 mmol), EDC (120 mg, 0.62 mmol), and HOBT (96 mg, 0.62 mmol) were dissolved in dry THF (3 ml). (3,4-Difluorophenyl)(phenyl)methanol (101 mg, 0.46 mmol) was dissolved in dry THF (2 ml) and then added to the reaction mixture. Triethylamine (203 μl, 1.46 mmol) was finally added, and the resulting reaction was stirred at room temperature overnight. The volatiles were evaporated, and the crude was taken up with EtOAc and washed with water and then with sat. NaHCO3. The organic phase was dried over sodium sulfate, filtered, and evaporated under vacuum. The crude was purified by flash chromatography (DCM/MeOH=9/1) to obtain (3,4-difluorophenyl)(phenyl)-methyl quinuclidine-3-carboxylate (65 mg, mixture of diastereoisomers).
