Toluene (20 mL), ethanol (6 mL), and water (2 mL) were added to commercially available 1-N—BOC-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine (1.00 g, 3.23 mmol), methyl 4-bromobenzoate (695 mg, 3.23 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxy biphenyl (266 mg, 0.65 mmol), palladium(II) acetate (73 mg, 0.32 mmol), and tripotassium phosphate (2.06 g, 9.70 mmol) under nitrogen atmosphere, and the mixture was stirred at 90° C. for 5 hours. The reaction mixture was cooled to room temperature and a saturated aqueous sodium bicarbonate solution and ethyl acetate were added for partition. The aqueous layer was extracted with ethyl acetate three times and then the organic layer was dried over anhydrous sodium sulfate and filtered. The solvent was evaporated and the resultant residue was purified with silica gel column chromatography (n-heptane:ethyl acetate=19:1-13:7) to obtain the title compound (0.99 g, 96%).
