反应详情

2,2-Difluorosuccinic acid (120 g, 0.78 moles) and trifluoroacetic anhydride (540 mL) are refluxed (bath temperature 80° C.) for 2 hours. Most of the trifluoroacetic acid is distilled utilizing a short Vigreux column, the final traces are removed under vacuum (12 mm Hg, 50° C.) and finally by stripping twice with carbontetrachloride. The oily residue solidifies on scratching with petroleum ether. Filtration and washing with petroleum either yields 2,2-difluorosuccinic anhydride as slightly violet crystals: 98 g (92%).

1. distillationMost of the trifluoroacetic acid is distilled
2. customthe final traces are removed under vacuum (12 mm Hg, 50° C.)
3. filtrationFiltration
4. washwashing with petroleum