反应详情

温度

110 °C

A mixture of 2-chloro-6-fluoro-pyridine (0.436 mL, 3.31 mmol) (Oakwood,), 3-pyridylboronic acid (448 mg, 3.65 mmol) (Combi-Blocks Inc.), and tetrakis(triphenylphosphine)palladium (0) (77 mg, 0.066 mmol) (Strem Chemicals) was purged with argon and dioxane (10 mL) and a 1 M solution of sodium carbonate (4.97 mL, 4.97 mmol) were added. The mixture was heated in a microwave at 110° C. for 30 min. The cooled reaction mixture was treated with 1 N NaOH and extracted with EtOAc (30 mL), washed with brine and dried over MgSO4, filtered and concentrated. Purification on the ISCO (12 g column, 70-100% EtOAc in hexanes) gave 6-fluoro-2,3′-bipyridine (581 mg, 3.34 mmol, 99% yield) as a pale yellow crystalline solid. m/z (ESI, +ve ion) 175.1 (M+H)+. 1H NMR (400 MHz, CDCl3) δ 9.20 (1H, d, J=1.6 Hz); 8.67 (1H, d, J=3.9 Hz); 8.34 (1H, d, J=8.0 Hz); 7.90 (1H, q, J=8.0 Hz); 7.67 (1H, dd, J=7.5, 2.4 Hz); 7.42 (1H, dd, J=7.9, 4.8 Hz); 6.94 (1H, dd, J=8.0, 2.9 Hz).

1. customwas purged with argon and dioxane (10 mL)
2. customThe cooled reaction mixture
3. extractionextracted with EtOAc (30 mL)
4. washwashed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customPurification on the ISCO (12 g column, 70-100% EtOAc in hexanes)