A mixture of 5-chloropyridin-3-yl trifluoromethanesulfonate (6.00 g, 22.9 mmol), bis(pinacolato)diboron (6.12 g, 24.1 mmol), potassium acetate (6.75 g, 68.8 mmol), and [1,1′-bis-(diphenylphosphino)ferrocene]palladium(II) dichloride (0.60 g, 0.82 mmol) in 30 mL DMF was heated to 80° C. under N2 for 2 hours. The reaction mixture was cooled to room temperature, and 5-(2-fluoro-6-iodophenyl)-2-methyl-2H-tetrazole (4.88 g, 16.1 mmol), sodium bicarbonate (2M, 34.4 mL, 68.8 mmol), and [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloride (0.60 g, 0.82 mmol) were added. The reaction mixture was heated to 80° C. overnight, then cooled to room temperature and partitioned between ethyl acetate and water. The organic extract was washed with water and brine, dried over Na2SO4, filtered and concentrated under vacuum. The residue was subjected to silica gel chromatography eluted with 0–30% ethyl acetate in hexanes to provide 3-chloro-5-[3-fluoro-2-(2-methyl-2H-tetrazol-5-yl)phenyl]pyridine that gave proton NMR spectra consistent with theory and a mass ion (ES+) of 290.11 for M+H+.
