[F:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([O:8][CH2:9][CH2:10][O:11][CH3:12])[N:3]=1.C([N-]C(C)C)(C)C.[Li+].CCCCCCC.O1CCCC1.C(C1C=CC=CC=1)C.[B:41](OC(C)C)([O:46]C(C)C)[O:42]C(C)C.FC1N=C(OCCOC)C(B(O)O)=CC=1>C1COCC1>[F:1][C:2]1[C:7]([B:41]([OH:46])[OH:42])=[CH:6][CH:5]=[C:4]([O:8][CH2:9][CH2:10][O:11][CH3:12])[N:3]=12-Fluoro-6-(2-methoxyethoxy)pyridine (1.13 g, 6.60 mmol) in THF (5 mL) was cooled to −60° C. and treated with lithium diisopropylamide, 2.0 M solution in heptane/tetrahydrofuran/ethylbenzene (4.95 mL, 9.90 mmol) (Aldrich) and stirred at −60° C. for 1 h. The mixture was then treated with triisopropyl borate (2.277 mL, 9.90 mmol) (Aldrich) and allowed to warm to RT over 30 min. It was then quenched by the addition of a saturated solution of ammonium chloride and stirred for 30 min. The reaction mixture was extracted with EtOAc (3×25 mL), dried over MgSO4, filtered and concentrated. Purification on the ISCO (12 g column, 5-100% EtOAc) gave a mixture of 2-fluoro-6-(2-methoxyethoxy)pyridin-3-ylboronic acid (226 mg, 1.051 mmol, 15.92% yield) and 6-fluoro-2-(2-methoxyethoxy)-pyridin-3-ylboronic acid as a semi-crystalline solid. m/z (ESI, +ve ion) 216.1 (M+H)+.
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