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:
Jul. 11, 2000
Filed:
Dec. 18, 1998
Patrick Michael Burke, Wilmington, DE (US);
E I. du Pont de Nemours and Company, Wilmington, DE (US);
DSM Desotech Inc., Geleen, NL;
Abstract
A process for the carbonylation of allylic butenol or butenyl ester of a carboxylic acid (e.g., crotyl acetate, 3-acetoxybutene-1 and mixtures thereof) in an anhydrous carboxylic acid solvent and production of beta-gamma unsaturated carboxylic acid anhydride (e.g., 3-pentenoic acid anhydride) utilizing a rhodium-containing catalyst (e.g., dicarbonylacetylacetonate rhodium(I)) promoted with a metal iodide (e.g., dicarbonylacetylacetonate rhodium(I), or the like). The following representative reaction showing a crotyl ester (i.e., a carboxylic acid ester of 2-buten-1-ol) as the reactant producing a corresponding pentenoic acid anhydride is illustrative of the overall carbonylation. ##STR1## Suitable allylic compounds are of the form ##STR2## where one of the groups R.sup.1, R.sup.2, and R.sup.3 is methyl and the other two groups are H and wherein R.sub.4 is selected from the group consisting of H and ##STR3## wherein R.sup.5 is selected from the group consisting of a C.sub.1 to C.sub.10 alkyl. Such a process is particularly useful in the production of beta-gamma unsaturated carboxylic acid anhydride without promoting the back reaction producing butadiene and a carboxylic acid.