Processes for producing tetrafluorophthalic anhydride and fluorobenzoic acids
US5523476A · kind A · utility
4Cited by
7References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 21, 1995 |
| Grant date | Jun 4, 1996 |
| Priority date | — |
| Expiry date | Feb 21, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D307/88
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing tetrafluorophthalic anhydride, which comprises chlorinating tetrachlorophthalic anhydride to obtain 3,3,4,5,6,7-hexachloro-1-[3H]-isobenzofuranone, then fluorinating it to obtain 3,4,5,6-tetrafluorophthaloyldifluoride and/or 3,3,4,5,6,7-hexafluoro-1-[3H]-isobenzofuranone, and further reacting the tetrafluorophthalolyldifluoride and/or the hexafluoro-1-[3H]-isobenzofuranone with an inorganic base or an organic acid to obtain tetrafluorophthalic anhydride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.