反应详情

To a 100 mL round-bottomed flask was added 3-amino-5-bromo-2-chloropyridine (855 mg, 4122 μmol), pyridine (5 ml), 3-(difluoromethoxy)benzenesulfonyl chloride (1000 μl, 4122 μmol). The reaction mixture was stirred at room temperature for overnight (ca 16 h). The solvent was removed in vacuo and the residue was dissolved in EtOAc (50 mL), washed with water (10 mL), saturated NaCl (10 mL), dried over Na2SO4, filtered and concentrated in vacuo and the residue was purified by silica gel chromatography, eluting with 20% EtOAc/hexanes to give N-(5-bromo-2-chloropyridin-3-yl)-3-(difluoromethoxy)benzenesulfonamide (566 mg, 33% yield) as a white solid. MS (ESI pos. ion) m/z calc'd for C12H8BrClF2N2O3S: 413.9. found 414.9. 1H NMR (300 MHz, chloroform-d) δ ppm 6.53 (t, J=72.27 Hz, 1H) 6.99 (s, 1H) 7.38 (dd, J=8.18, 1.75 Hz, 1H) 7.52 (t, J=8.04 Hz, 1H) 7.58 (s, 1H) 7.62-7.68 (m, J=1.17 Hz, 1H) 8.16 (d, J=2.34 Hz, 1H) 8.21 (d, J=2.19 Hz, 1H)

1. customThe solvent was removed in vacuo
2. dissolutionthe residue was dissolved in EtOAc (50 mL)
3. washwashed with water (10 mL), saturated NaCl (10 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customthe residue was purified by silica gel chromatography
8. washeluting with 20% EtOAc/hexanes