Preparation of vitamin E and DL-alpha-tocopherol acetate

摘要

Preparation of dl- alpha -tocopherol (vitamin E) or DL- alpha -tocopheryl acetate involves acid-catalysed reaction of 2,3,5-trimethyl-hydroquinone (TMH) with phytol or isophytol in a solvent (III) at elevated temperature, optionally followed by esterification with acetic anhydride (IV). The novelty is that reaction is carried out at 50-200 deg C in a cyclic carbonate of formula (I) or a psi -lactone of formula (II) as solvent. R1, R2, R3 = H, ethyl (Et) or methyl (Me); R4 = H, phenyl or alkyl with up to 20 carbon (C) atoms, optionally substituted by phenyl or groups containing oxygen (O), preferably H, Me, Et, isopropyl, phenyl or methoxymethyl.