Br[C:2]1[C:7]([F:8])=[CH:6][CH:5]=[CH:4][N:3]=1.C([Li])CCC.[CH2:14]([Sn:18](Cl)([CH2:23][CH2:24][CH2:25][CH3:26])[CH2:19][CH2:20][CH2:21][CH3:22])[CH2:15][CH2:16][CH3:17]>C1COCC1>[F:8][C:7]1[C:2]([Sn:18]([CH2:19][CH2:20][CH2:21][CH3:22])([CH2:23][CH2:24][CH2:25][CH3:26])[CH2:14][CH2:15][CH2:16][CH3:17])=[N:3][CH:4]=[CH:5][CH:6]=1Cool a solution of 2-bromo-3-fluoro-pyridine (542 mg, 3.08 mmol) in dry THF to −78° C. using a dry ice acetone bath. Add n-butyl-lithium (1.6 M in THF, 2.0 mL) to the reaction mixture dropwise via syringe over a 20 minute period. After stirring for 1.5 hours at −78° C., add tributyltin chloride slowly via syringe and remove the cooling bath. After 2 hours, partition the reaction mixture between EtOAc and brine, dry the EtOAc layer (Na2SO4) and remove the solvents under reduced pressure. Flash chromatography (ether/hexanes) yields 3-fluoro-2-tributylstannanyl-pyridine as a colorless oil.
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