| 摘要 |
chemical industry. SUBSTANCE: described is method of preparing dl-alpha-tocopherol and dl-alpha- tocopheryl acetate by acid-catalyzed reaction of 2,3,5-trimethylhydroquionone with phytol in solvent at elevated temperature, and followed, if required by esterification of the resulting tocopherol with acetic anhydride. Reaction of 2,3,5-trimethyl hydroquinone with phytol or isophytol is carried out in cyclic carbonate of general formula I alpha- or in alpha--lactone of general formula II: wherein gamma are H, methyl or ethyl, preferably H or methyl, and is H, phenyl or alkyl with total number of carbon atoms up to 20 , which is substituted by phenyl or oxygen-containing groups, preferably H, methyl, ethyl, isopropyl, phenyl or methoxymethyl as solvent at temperatures from 50 to 200 C. EFFECT: simplified continuous process and high yield of the desired product. 9 cl, 12 ex |
