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:
Aug. 27, 2002
Filed:
Nov. 13, 2000
Sijoon Lee, Taejon, KR;
Jeong-Soo Kim, Taejon, KR;
Young-Seek Yoon, Taejon, KR;
Myung-Jun Kim, Taejon, KR;
Jun-Tae Choi, Taejon, KR;
Byong-Sung Kwak, Taejon, KR;
Sk Corporation, Seoul, KR;
Abstract
Disclosed is a method for preparing DL-&agr;-tocopherol through the condensation of isophytol or phytol derivatives and trimethylhydroquinone (TMHQ) using a catalyst system comprising a divalent metal halogen compound, silica gel and/or silica-alumina, and a Brönsted acid. Isophytol or phytol derivatives are slowly added to trimethylhydroquinone for the condensation thereof at 80 to 135° C. over 30 to 60 min in the presence of the metal halogen and the silica gel and/or silica-alumina. In the presence of the Brönsted acid, the intermediates are converted into the product. The silica gel and/or silica-alumina is washed with a polar solvent for recovery. The catalyst system can remarkably reduce side-reactions upon the condensation of isophytol or phytol derivatives and TMHQ, thus producing DL-&agr;-tocopherol with a high purity at a high yield. Also, the catalyst system can be regenerated in succession because of its being able to avoid the decrease of catalytic activity attributed to the adsorption of organic materials; thus reducing the production cost of DL-&agr;-tocopherol and the quantity of industrial wastes generated. With these advantages, the catalyst system can be effectively used in preparing highly pure DL-&agr;-tocopherol at a high yield on a commercial scale.