Trimethylhydroquinone → 6-Hydroxy-4,4,5,7,8-pentamethyl-3,4-dihydrocoumarin
Reaktionsgleichung
[CH3:1][C:2]1[C:8]([CH3:9])=[C:7]([OH:10])[C:6]([CH3:11])=[CH:5][C:3]=1[OH:4]>CS(O)(=O)=O>[OH:10][C:7]1[C:6]([CH3:11])=[C:5]2[C:3](=[C:2]([CH3:1])[C:8]=1[CH3:9])[O:4][C:3](=[O:4])[CH2:2][C:8]2([CH3:9])[CH3:7]Komponenten
3
Edukt 1
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- 70 °C
Versuchsvorschrift
A mixture of 2,3,5-trimethyl hydroquinone (10 g, 0.0657 mol) and methyl 1,1-dimethylacrylate (7.5 g, 0.0657) in 50 ml of methanesulfonic acid was heated to 70° C. for 2 hours. Upon cooling to room temperature, the mixture was poured into 100 ml of ice-cold water. The resulting mixture was extracted three times with ethyl acetate, and the combined organic layers were washed with water and dried over sodium sulfate. After removal of the majority of ethyl acetate, the mixture was cooled −20° C. The pale white solid was collected by filtration, washed with cold ethyl acetate and dried under vacuum oven. The yield was 75%. 1H NMR (300 MHz, CD2Cl2) δ ppm: 4.69 (s, 1H, OH), 2.59 (s, 2H, CH2), 2.53 (s, 3H, CH3), 2.35 (s, 3H, CH3), 2.20 (s, 3H, CH3), 1.57 (s, 3H, CH3), 1.44 (s, 3H, CH3); MS (m/e): 235 (M+).