反应详情

温度

80 °C

To a solution of 3-methyl-thieno[3,2-b]pyridine-6-carboxylic acid ethyl ester (1.2 g) in carbon tetrachloride (50 mL) was added N-bromosuccinimide (2.4 g) followed by AIBN (50 mg) and the resulting mixture was heated at reflux for 4 hours. The reaction mixture was cooled; the solids were removed by filtrations and copiously washed with carbon tetrachloride. The filtrate was evaporated under reduced pressure, the residue was dissolved in dimethyl sulfoxide (20 mL) and the resulting mixture was heated at 80° C. for 1 hour. The reaction mixture was cooled, diluted with water, basified by addition of a saturated aqueous solution of sodium bicarbonate and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by flash chromatography (acetone/DCM, 5/95) to give 0.8 g of 3-formyl-thieno[3,2-b]pyridine-6-carboxylic acid ethyl ester.

1. temperaturethe resulting mixture was heated
2. temperatureat reflux for 4 hours
3. temperatureThe reaction mixture was cooled
4. customthe solids were removed by filtrations
5. washcopiously washed with carbon tetrachloride
6. customThe filtrate was evaporated under reduced pressure
7. dissolutionthe residue was dissolved in dimethyl sulfoxide (20 mL)
8. temperatureThe reaction mixture was cooled
9. additiondiluted with water
10. additionbasified by addition of a saturated aqueous solution of sodium bicarbonate
11. extractionextracted with ethyl acetate
12. washThe combined organic layers were washed with brine
13. dry with materialdried over anhydrous sodium sulfate
14. filtrationfiltered
15. customevaporated under reduced pressure
16. customThe residue was purified by flash chromatography (acetone/DCM, 5/95)