反应详情

α-Phenylthio-2-thiopheneacetic acid (890 mg, 3.56 mmol) was dissolved in acetic acid (6 ml), then zinc dust (350 mg, 5.4 mmol) was added and the mixture was heated under reflux with vigorous stirring. After 30 min., zinc dust (350 mg, 5.4 mmol) was added again, and the mixture was heated under reflux for another 4 hr. with stirring, then cooled to room temperature, and most of the solvent was removed by distillation. Water and ethyl acetate were added and the precipitate was filtered off by the use of celite, and the layers of the filtrate were separated. The organic layer was washed with an aqueous solution of sodium chloride and dried with anhydrous magnesium sulfate. After filtration, the solution was concentrated under a reduced pressure and the crystals thus obtained were further recrystallized from ethyl acetate: n-hexane to give 2-thiopheneacetic acid (430 mg) melting at 62° C. (literature value: 62°-65° C.).

1. temperaturethe mixture was heated
2. temperatureunder reflux with vigorous stirring
3. temperaturethe mixture was heated
4. temperatureunder reflux for another 4 hr
5. custommost of the solvent was removed by distillation
6. additionWater and ethyl acetate were added
7. filtrationthe precipitate was filtered off by the use of celite
8. customthe layers of the filtrate were separated
9. washThe organic layer was washed with an aqueous solution of sodium chloride
10. dry with materialdried with anhydrous magnesium sulfate
11. filtrationAfter filtration
12. concentrationthe solution was concentrated under a reduced pressure
13. customthe crystals thus obtained
14. customwere further recrystallized from ethyl acetate