反应详情

1.0 g (6.85 mmol) of galactal is taken up in 0.5-1.5 ml of H2O, 8 g of crushed molecular sieves are added, and the mixture is stirred with 1 g of Candida lipase AY-20 (Meito, Sangyo) or 1 g of lipase P (Amano) in 10-15 ml of vinyl benzoate at room temperature for 8-10 h. Filtering off the enzyme, concentration of the solution in vacuo, taking up the residue in ethyl acetate and extracting it with aqueous NaHCO3 solution, and subsequent chromatography on silica gel (ethyl acetate/hexane 1:1) result in 65-68% (about 1130 mg) of the desired 6-O-benzoylgalactal.

1. addition8 g of crushed molecular sieves are added
2. filtrationFiltering off the enzyme, concentration of the solution in vacuo
3. extractionextracting it with aqueous NaHCO3 solution, and subsequent chromatography on silica gel (ethyl acetate/hexane 1:1)
4. customresult in 65-68% (about 1130 mg) of the desired 6-O-benzoylgalactal