Arylalkanoic acid process improvement
US4623736A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1982 |
| Grant date | Nov 18, 1986 |
| Priority date | — |
| Expiry date | Jul 9, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/09
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
In preparing arylalkanoic acids, e.g. ibuprofen or naproxen, via the conversion of the selected .alpha.-haloketal derivative of a 1-haloethyl aryl ketone to the haloalkyl ester of the arylalkanoic acid using a zinc salt catalyst the improvement comprising reacting a ring-substituted 6-membered ring ketal of the selected 1-haloethyl C.sub.6 -C.sub.12 -aryl ketone with a soluble zinc carboxylate salt to form the corresponding 3-haloalkyl arylalkanoic acid ester. The ester is converted to the alkali metal salt of the acid with base in an aqueous/water insoluble organic liquid mixture and the crude salt is converted to the corresponding acid in an aqueous/water insoluble solvent mixture for the acid, the organic solution of the acid is washed with a pH 7.0 to 8.0 buffer solution, and the arylalkanoic acid product is separated from the mother liquor which mother liquor is recycled to the alkali metal arylalkanoate salt forming step of the process to accumulate and recover the arylalkanoic acid values which remained in the mother liquor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.