Preparation of optically active .alpha.-(hydroxyphenoxy)alkanecarboxylic acids and derivatives thereof
US5654338A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 25, 1995 |
| Grant date | Aug 5, 1997 |
| Priority date | — |
| Expiry date | Apr 25, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C67/31
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Optically active .alpha.-(hydroxyphenoxy)-alkanecarboxylic acids or derivatives thereof, for example D-2-(4-hydroxyphenoxy)propionic acid or lower alkyl ester thereof, are prepared by (a) saponifying an alkyl ester of an optically active .alpha.-halogeno-alkanecarboxylic acid, in an alcoholic solvent medium, by reacting same with an aqueous solution of an alkali metal hydroxide, thereby providing a solution of an alkali metal salt of an optically active .alpha.-halogeno-alkanecarboxylic acid, (b) next reacting the step (a) solution thus provided with a dihydroxybenzene or salt thereof, in the presence of an alkali metal hydroxide and in an alcoholic solvent medium, and thence (c) recovering the optically active .alpha.-(hydroxyphenoxy)-alkanecarboxylic acid or derivative thereof from the medium of reaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.