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:
Oct. 25, 1994
Filed:
Feb. 07, 1994
Charles A McCombs, Kingsport, TN (US);
Eastman Chemical Company, Kingsport, TN (US);
Abstract
Preparing cyclohexanediones of the formula ##STR1## an aldehyde is reacted with a ketene to give a polymer having the repeating unit ##STR2## wherein n ranges from about 2 to about 1,000. The polymer is hydrolyzed to produce a mixture of an unsaturated acid of the formula R--CH.dbd.C(R.sub.1)--COOH and a hydroxy ester or acid of the formula R--CH(OH)C(R.sub.1)(R.sub.2)--COOR.sub.3, the mixture is then contacted with an esterifying agent to convert the acids to esters. The ester mixture is contacted with a dehydrating agent to convert the hydroxy ester to unsaturated ester of the formula R--CH.dbd.C(R.sub.1)--COOR.sub.3. The unsaturated ester is contacted with a basic catalyst to cyclize it to the cyclic dione ester of the formula ##STR3## and this ester is then hydrolyzed and decarboxylated to give the cyclohexanedione give the product wherein: