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:
Nov. 01, 1988
Filed:
Dec. 02, 1986
Applicant:
Inventor:
Klaus Langerbeins, Langen, DE;
Assignee:
Rohm GmbH, Darmstadt, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07C / ;
U.S. Cl.
CPC ...
260549 ; 560204 ; 260413 ; 260546 ;
Abstract
Method for making alpha, beta-unsaturated carboxylic acid anhydrides by carbonylation of esters of acrylic acid or methacrylic acid in the presence of a catalyst system containing at least one noble metal from group VIII of the periodic table, for example rhodium, the reaction being carried out at 70.degree. C. to 350.degree. C. and at pressures from 1 to 500 bar in the presence of a halogen or of a halogen compound, and in particular of iodine or an iodine compound, as a promoter.