Resolution of D,L-cis and D,L-trans 2,2-dimethyl-3-(2,2-dihalovinyl)-cyclopropane-1-carboxylic acids and salts thereof
US4328173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1980 |
| Grant date | May 4, 1982 |
| Priority date | — |
| Expiry date | Mar 17, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/487
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A novel process for the resolution of D,L-cis and D,L-trans 2,2-dimethyl-3-(2,2 -dihalovinyl)-cyclopropane-1-carboxylic acids of the formula ##STR1## wherein X is selected from the group consisting of fluorine, chlorine and bromine comprising salifying the said acid with an optically active base selected from the group consisting of D-ephedrine, L-ephedrine, D-N-methyl-ephedrine, L-N-methylephedrine, D-pseudo-ephedrine and L-pseudo-ephedrine to form the corresponding salt, recovering the said salt and subjecting the latter to acid hydrolysis to obtain the corresponding resolved acid which are intermediates for the synthesis of esters having a remarkable insecticidal activity.
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