Process for the preparation of dihalovinylcyclopropanecarboxylic acids
US4419524A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1982 |
| Grant date | Dec 6, 1983 |
| Priority date | — |
| Expiry date | Feb 19, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/09
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a new process for the preparation of cyclopropanecarboxylic acids of the formula (I) ##STR1## wherein X and Y independently stand for halogen, by the alkaline hydrolysis of the corresponding alkyl esters having 1 to 6 carbon atoms in the alkyl moiety, in or without a water-miscible organic solvent, in the presence of a phase transfer catalyst. The hydrolysis is carried out with a 2 to 50% by weight aqueous alkali hydroxide solution. If desired, under suitable conditions the cis/trans ratio of the original ester can be altered in the end products. The cyclopropanecarboxylic acids of the formula (I) are obtained in a high purity and are useful intermediates of insecticidally active pyrethroids.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.