反应详情

温度

55 °C

To a solution of 6-chloro-2-isopropoxy-nicotinamide (2.87 g, 13.37 mmol) and pyridine (6.48 mL, 80.22 mmol) in acetonitrile (25 mL) was added phosphorus oxychloride (3.68 mL, 40.13 mmol) over a period of 5 min. The reaction was stirred at 55° C. for 1 h. Acetonitrile was evaporated in vacuo and the resulting residue was neutralized with 1N NaOH at 0° C. until pH reached to ˜7. The reaction mixture was extracted with EtOAc (100 mL). The organic layer was collected and the aqueous layer was further extracted with EtOAc (3×50 mL). All organics were combined washed with brine (2×25 mL), dried over anhydrous Na2SO4, filtered, and concentrated to give yellow oil. Purification was accomplished by flash chromatography on silica gel using 5-25% EtOAc/hexanes gradient elution to yield the title compound (2.1 g, 81%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.28 (d, J=8.2 Hz, 1 H), 7.27 (d, J=8.2 Hz, 1 H), 5.34-5.20 (m, 1 H), 1.33 (d, J=6.2 Hz, 6 H).

1. customAcetonitrile was evaporated in vacuo
2. customwas neutralized with 1N NaOH at 0° C. until pH
3. extractionThe reaction mixture was extracted with EtOAc (100 mL)
4. customThe organic layer was collected
5. extractionthe aqueous layer was further extracted with EtOAc (3×50 mL)
6. washAll organics were combined washed with brine (2×25 mL)
7. dry with materialdried over anhydrous Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customto give yellow oil
11. customPurification
12. washwas accomplished by flash chromatography on silica gel using 5-25% EtOAc/hexanes gradient elution