The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 26, 2006
Filed:
Dec. 07, 2002
Werner Bonrath, Freiburg, DE;
Michael Schneider, Frick, CH;
Werner Bonrath, Freiburg, DE;
Michael Schneider, Frick, CH;
DSM IP Assets B.V., TE Heerlen, NL;
Abstract
A process for the manufacture of 2,3,5-trimethylhydroquinone diacylate comprising reacting ketoisophorone with an acylating agent in the presence of a NH- or CH-acidic catalyst, particularly certain bis(perfluorinated hydrocarbyl sulphonyl) imides and metal salts thereof and, respectively, certain tris(perfluoroalkanesulphonyl or pentafluorobenzenesulphonyl) methanes and metal salts thereof. The acylating agent is particularly an acid anhydride, an acyl halide or an enol ester. The so-obtained 2,3,5-trimethylhydroquinone diacylate can be converted into (all-rac)-α-tocopherol by transesterification to yield 2,3,5-trimethylhydroquinone and reaction of the latter with isophytol. (all-rac)-α-Tocopherol itself is the most active member of the vitamin E group.