Process for the preparation of alpha-tocopherol and alpha-tocopheryl-acetate with liquid or supercritical carbondioxyde

摘要

Process for the preparation of alpha -tocopherol or tocopheryl acetate by cyclocondensation of trimethylhydroquinone with phytol or isophytol in the presence of an acidic catalyst and of a solvent, optionally followed by acetylation, the process being characterised in that the cyclocondensation and the optional sequent acetylation steps are carried out in liquid or supercritical carbon dioxide as solvent.