METHOD OF SYNTHESIS OF ALPHA-TOCOPHEROL OR ALPHA-TOCOPHERYL ACETATE BY INTERACTION OF TRIMETHYLHYDROQUINONE AND PHYTOL OR ISOPHYTOL WITH RECOVERY OF ZINC HALOGENIDE CATALYST OF CONDENSATION TO PROCESS Russian patent published in 2002 - IPC

FIELD: organic chemistry, chemical technology, vitamins. SUBSTANCE: invention relates to the improved method of synthesis of α-tocopherol or α-tocopheryl acetate that are used as an antioxidant in the nutrition of humans and animals. Invention describes a method of synthesis of α-tocopherol or α-tocopheryl acetate by interaction of 2,3,5-trimethylhydroquinone with phytol or isophytol in the presence of zinc halogenide catalyst of condensation and donor of protons in solvent and if necessary with the following esterification with acetane hydride. Method involves: a) interaction is carried out in nonpolar solvent nonmixing or nonsignificantly mixing with water; b) necessary zinc halogenide is added to interaction as a mixture of from 1 to 4 moles of water per a mole of zinc halogenide. Method ensures to use the necessary zinc halogenide in the form of easily dosing mixture of zinc halogenide and water without deterioration of the yield and purity of tocopherol and opens a way to a benefit recovery of zinc halogenide in the process by separation and extraction after interaction and recovery of zinc halogenide as 60-9- weight % solution or pulp feeding by a pump. EFFECT: improved method of synthesis. 8 cl, 6 tbl