p-Toluenesulfonic acid → Ethyl 3-oxo-3-(2,4,5-trifluoro-3-methylphenyl)propanoate
Reaktionsgleichung
[F:1][C:2]1[C:20]([CH3:21])=[C:19]([F:22])[C:18]([F:23])=[CH:17][C:3]=1[C:4]([CH:6](C(OCC)=O)[C:7]([O:9][CH2:10][CH3:11])=[O:8])=[O:5].C1(C)C=CC(S(O)(=O)=O)=CC=1>O>[F:1][C:2]1[C:20]([CH3:21])=[C:19]([F:22])[C:18]([F:23])=[CH:17][C:3]=1[C:4]([CH2:6][C:7]([O:9][CH2:10][CH3:11])=[O:8])=[O:5]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
A mixture of diethyl 2-(2,4,5-trifluoro-3-methylbenzoyl)malonate (8.10 g) and p-toluenesulfonic acid (9.6 mg) in water (9.6 ml) was refluxed for 3 hours with stirring vigorously. After cooling, the reacting mixture was extracted with dichloromethane. The organic layer was washed with 7% aqueous sodium bicarbonate solution, dried over anhydrous sodium sulfate and then concentrated under reduced pressure. The resulting residue was allowed to stand in a refrigerator for 2 days, the resulting precipitate was collected by filtration and recrystallized from n-hexane to give the title compound (0.51 g) as colorless prisms, mp 38°-39° C.