反应详情

温度

3040 °C

112.5 ml (116 g, 2.312 mol) of hydrazine hydrate were added slowly to a solution of 90 g (0.489 mol) of methyl(3-methylthiophen-2-yl)oxoacetate in 260 ml of diethylene glycol, and the mixture was heated under reflux for 30 min. After cooling to 3040° C., 82 g (1.246 mol) of potassium hydroxide were added a little at a time, which was accompanied by a temperature increase to 70-80° C. with simultaneous evolution of nitrogen. The mixture was then slowly heated to reflux and stirred at this temperature for a total of 5 h. After cooling to room temperature, the mixture was poured into 2 l of water, adjusted to pH=1 using 250 ml of semi-concentrated hydrochloric acid and extracted with ethyl acetate. The organic phase was dried over magnesium sulphate and filtered off and the solvent was removed, which gave 50 g of (3-methylthiophen-2-yl)acetic acid. Yield: 66%. 1H-NMR (DMSO): δ=7.25 (d, 1H), 6.84 (d, 2H), 3.67 (s, 2H), 2.11 (s, 3H).

1. temperaturethe mixture was heated
2. temperatureunder reflux for 30 min
3. temperatureincrease to 70-80° C. with simultaneous evolution of nitrogen
4. temperatureThe mixture was then slowly heated
5. temperatureto reflux
6. temperatureAfter cooling to room temperature
7. extractionextracted with ethyl acetate
8. dry with materialThe organic phase was dried over magnesium sulphate
9. filtrationfiltered off
10. customthe solvent was removed