反应详情

To a solution of commercial 4-hydroxy-mandelic acid (10.0 gr, 0.05 mol) in acetone (160 ml), 2,2-dimethoxypropane (56 mL, 0.45 mol) and BF3.Et2O (0.4 ml, 0.48 mol)) were added under vigorous stirring. The solution was left stirring for 3 hours. After adding of triethylamine (TEA) (2 mL), the solvent was evaporated under vacuum and the crude diluted in a saturated solution of Na2HCO3 (30 ml) and extracted with EtOAc (3×30 ml). The collected organic extracts were washed with brine (2×25 mL), dried over Na2SO4 and evaporated under vacuum to give the intermediate 5-(4-hydroxyphenyl)-2,2-dimethyl-1,3-dioxolan-4-one (10.21 g) as yellow oil, pure enough to be used in the further step without any purification.

1. waitThe solution was left
2. customthe solvent was evaporated under vacuum
3. additionthe crude diluted in a saturated solution of Na2HCO3 (30 ml)
4. extractionextracted with EtOAc (3×30 ml)
5. washThe collected organic extracts were washed with brine (2×25 mL)
6. dry with materialdried over Na2SO4
7. customevaporated under vacuum