[CH2:1]([O:3][C:4]1[C@@H:9]([C@H:10]([C:12](=C(C)C)[OH:13])[OH:11])[O:8][C:6](=[O:7])[C:5]=1[OH:17])[CH3:2]>O.C(O)C>[CH2:1]([O:3][C:4]1[C@@H:9]([C@H:10]([CH2:12][OH:13])[OH:11])[O:8][C:6](=[O:7])[C:5]=1[OH:17])[CH3:2]12.4 g of the 3-O-ethyl-isopropylidene ascorbic acid prepared in Example 1 was dissolved in the mixed solvent of distilled water (10 ml)/ethanol (90 ml) together with 1.1 g of Nafion H, followed by stirring at 60° C. for 2 hours. Nafion H was eliminated by filtering and the mixture was concentrated into crude crystalline 3-ethyl-ascorbic acid. The crude crystalline 3-ethyl-ascorbic acid was re-crystallized in ethylacetate/ethanol (8:2) to give 7.6 g of white crystalline 3-O-ethyl-ascorbic acid.
Loading…