Method of making 3-hydroxy-2,4,5-trifluorobenzoic acid
US5233082A · kind A · utility
4Cited by
5References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1982 |
| Grant date | Aug 3, 1993 |
| Priority date | — |
| Expiry date | Nov 16, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C235/56
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Disclosed is a method of making 3-hydroxy-2,4,5-trifluorobenzoic acid. A aqueous solution is prepared of an alkali metal base and a tetrafluorophthalimide. The solution is heated to produce a mixture of a salt of a 4-hydroxy-3,5,6-trifluorophthalamic acid and a salt of a 3-hydroxy-2,4,5-trifluorobenzamide. The solution is neutralized with acid to form a precipitate of the 4-hydroxy-3,5,6-trifluorophthalamic acid and the 3-hydroxy-2,4,5-trifluorobenzamide. The precipitate is reacted with a mineral acid to produce 3-hydroxy-2,4,5-trifluorobenzoic acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.