反应详情

Cyclohexene (27.3 g, 0.33 mol), crotonic acid (28.7 g, 0.33 mol) and polyphosphoric acid (300 mL) were mechanically stirred under a nitrogen atmosphere at 60° C. for 30 minutes. The slurry was poured into water and the aqueous solution extracted with diethyl ether. The diethyl ether extract was washed successively with a 10 percent NaHCO3 solution and a saturated NaCl solution. The organic extract was dried over anhydrous MgSO4. The solution was filtered and the solvent removed under reduced pressure. The crude product was purified via vacuum distillation (bp 87°-92° C. at 5 mm) to give 32.6 g (66 percent) of purified material.

1. extractionthe aqueous solution extracted with diethyl ether
2. extractionThe diethyl ether extract
3. washwas washed successively with a 10 percent NaHCO3 solution
4. extractionThe organic extract
5. dry with materialwas dried over anhydrous MgSO4
6. filtrationThe solution was filtered
7. customthe solvent removed under reduced pressure
8. distillationThe crude product was purified via vacuum distillation (bp 87°-92° C. at 5 mm)