摘要 |
The present invention is concerned with a novel process for the manufacture of alpha-tocopheryl acetate which comprises reacting 2,3,6-trimethylhydroquinone-1-acetate with a compound selected from the group consisting of phytol (formula IV with R = OH), iso-phytol (formula III with R = OH), and (iso) phytol derivatives represented by the following formulae III and IV with R = C2-to C5-alkonoyloxy, benzoyloxy, mesyloxy, benzenesul-fonyloxy or tosyloxy, (IV) in the presence of a catalyst of the formula Mn+ (R1SO3-)n, wherein Mn+ is a silver, copper, gallium, hafnium or rare earth metal cation, n is the valence of the cation Mn+, and R1 is fluorine, C1- 8-perfluoroalkyl or perfluoroaryl, and, if required, cyclizing any 3- phytyl-2,5,6-trimethylhydroquinone-1-acetate or a double bond isomer thereof obtained as an intermediate reaction product, to produce alpha- tocopheryl acetate. In the catalyst Mn+ is preferably Ag+ , Cu+, Ga3+, Sc3+, Lu3+, Ho3+ , Tm3+, Yb3+ or Hf4+.
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