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. 15, 2000
Filed:
Apr. 21, 1999
Applicant:
Inventors:
Nongyuan Shi, Hainburg, DE;
Mario Scholz, Grundau, DE;
Steffen Hasenzahl, Maintal, DE;
Horst Weigel, Rodenbach, DE;
Bernd Drapal, Alzenau, DE;
Ralph McIntosh, Hanau, DE;
Hans J Hasselbach, Gelnhausen, DE;
Klaus Huthmacher, Gelnhausen, DE;
Assignee:
Degussa-Huls AG, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560 79 ; 560231 ;
Abstract
Preparation of 2,3,5-trimethylhydroquinone diesters by rearrangement of 2,6,6-trimethylcyclohex-2-ene-1,4-dione (4-oxo-isophorone, ketoisophorone) in the presence of a solid, acid catalyst and an acylating agent, for example carboxylic acid anhydrides or carboxylic acid halides. The 2,3,5-trimethylhydroquinone diester may then optionally be saponified to the free 2,3,5-trimethylhydroquinone, which is a valuable building block in the synthesis of vitamin E.