Process for producing carboxylic acid anhydrides
US4830789A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1986 |
| Grant date | May 16, 1989 |
| Priority date | — |
| Expiry date | Dec 24, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/567
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides (1) a process for producing a colorless aromatic acid anhydride having a high purity in a high yield by reacting an aromatic carboxylic acid having a carboxyl group bonded to the aromatic nucleus with a lower aliphatic acid anhydride in the presence of at least one metal ion selected from the group consisting of ions of metals of Groups, I, II, III, V, VII and VIII of the periodic table and (2) a process for producing an acid anhydride by an exchange reaction of an organic carboxylic acid anhydride and a carboxylic acid in the presence of at least 5 ppm of at least one metal ion selected from the group consisting of Co, Ni, Mn, Fe, Li, Na, K, Mg, Ca, Cu, Zn, Al, Ti and V ions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.