[CH2:1]([OH:4])[CH2:2][OH:3].C1(C)C=CC(S(O)(=O)=O)=CC=1.[C:16]([C:20]1[CH:21]=[C:22]([CH2:26][CH2:27][CH:28]=O)[CH:23]=[CH:24][CH:25]=1)([CH3:19])([CH3:18])[CH3:17]>C1CCCCC1>[C:16]([C:20]1[CH:21]=[C:22]([CH2:26][CH2:27][CH:28]2[O:4][CH2:1][CH2:2][O:3]2)[CH:23]=[CH:24][CH:25]=1)([CH3:19])([CH3:18])[CH3:17]Ethylene glycol (15 mL, 0.27 mol, 1.2 eq), paratoluene sulfonic acid (430 mg, 1% w/w) and cyclohexane (50 mL) were charged into a 1 L three-necked round-bottom flask, equipped with a dean and stark, a reflux condenser and a mechanical stirrer. 3-(3-tert-butylphenyl)propanal (50.6 g, gc purity of 85%, 0.22 mol) was added dropwise at ambient temperature. After stirring for 2 h at reflux, the reaction mixture was cooled to ambient temperature and washed twice with water (50 mL), saturated aqueous NaHCO3, dried over magnesium sulphate and concentrated to give 2-[2-(3-tert-butylphenyl)ethyl]-1,3-dioxolane in the form of a pale yellow coloured oil (60 g, gc purity>84%; yield>95%). The material was used as such for the next step.
Wird geladen…
