Perfluorinated Brønsted 'Superacids': Powerful Catalysts for the Preparation of Vitamin E

Abstract

The key-step in the industrial synthesis of (all-rac)-?-tocopherol (synthetic vitamin E) is the condensation reaction of trimethylhydroquinone with the C20 building block isophytol. For this Friedel-Crafts-type reaction, perfluorinated NH- and CH-acidic compounds (perfluoroalkyl(aryl)sulfonyl imides and methides) have been applied as excellent catalysts, preferably in biphasic solvent systems.

Keywords

• Biphasic catalysis
• Friedel-crafts alkylation
• Perfluorinated nh-acidic imides
• &alpha-tocopherol
• Tris(perfluoroalkylsulfonyl) methanes