反应详情

To a suspension of 2-iodo-isonicotinic acid (can be prepared according to J. Med. Chem. (19) 490, 1976) (24.9 g, 100 mmol) in methanol (100 mL) was added sulfuric acid (concentrated, 11 mL, 205 mmol) and the mixture was stirred at ambient temperature for 5 days followed by heating to reflux for 3 h. The reaction mixture was cooled to ambient temperature, concentrated and poured into ice cold aqueous sodium hydrogencarbonate (half-saturated) and was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and concentrated. Purification by chromatography (SiO2, heptane:ethyl acetate=85:15 to 80:20) afforded the title compound (20.4 mg, 77%) as a light yellow solid. MS: m/e=263.0 [M]+.

1. temperatureby heating
2. temperatureto reflux for 3 h
3. temperatureThe reaction mixture was cooled to ambient temperature
4. concentrationconcentrated
5. additionpoured into ice cold aqueous sodium hydrogencarbonate (half-saturated)
6. extractionwas extracted with ethyl acetate
7. washThe combined organic layers were washed with brine
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated
10. customPurification by chromatography (SiO2, heptane:ethyl acetate=85:15 to 80:20)