Process for making certain benzoic acid compounds
US6348624B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1998 |
| Grant date | Feb 19, 2002 |
| Priority date | — |
| Expiry date | Mar 19, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The subject invention involves processes for making 2,4-difluoro-3-Q1-benzoic acid, wherein Q1 is derived from an electrophilic reagent, comprising the steps of: (a) treating 1-bromo-2,4-difluorobenzene with a strong, non-nucleophilic base; then treating with an electrophilic reagent which provides Q1, or a functional moiety which is then transformed to Q1, producing 1-bromo-2,4-difluoro-3-Q1-benzene; (b) treating the 1-bromo-2,4-difluoro-3-Q1-benzene with an alkali or alkaline earth metal or organometallic reagent; then treating with carbon dioxide, or with a formylating agent followed by oxidation, to produce 2,4-difluoro-3-Q1-benzoic acid.The subject invention also involves optional additional steps to further modify Q1, or to substitute a non-hydrogen moiety at the 5-position, at the 6-position, or at both, of the phenyl ring of the 2,4-difluoro-3-Q1-benzoic acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.