Insecticidal composition comprising more than one active ingredient
US5110976A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 1991 |
| Grant date | May 5, 1992 |
| Priority date | — |
| Expiry date | May 7, 2011 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01N53/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process is disclosed for preparing a synergistic, crystalline product consisting of solely enantiomer pair 1RCisS and 1SCisR and enantiomer pair 1RTransS and 1STransR of cypermethrin in a 3:7 to 5:5 crystalline mixture, which comprises the steps of: (a) epimerizing an oily melt or a saturated solution of enantiomer pair 1RCisS and 1SCisR and enantiomer pair 1RTransS and 1STransR in a ratio other than 3:7 to 5:5, or a mixture of enantiomer pair 1RCisS and 1SCisR, enantiomer pair 1RTransS and 1STransR together with enantiomer pair 1RCisR and 1SCisS and enantiomer pair 1RTransR and 1STransS, said saturated solution including a protic or apolar, aprotic inert organic solvent by treating said oily melt or saturated solution with an organic or inorganic base at a temperature of -15.degree. C. to 30.degree. C. to precipitate crystals consisting solely of the 1RCisS and 1SCisR and the 1RTransS and 1RTransR enantiomer pairs in a 3:7 to 5:5 weight ratio; (b) isolating the precipitated crystals consisting solely of the enantiomer pairs 1RCisS and 1SCisR and 1RTransS and 1STransR at -10.degree. to 30.degree. C., optionally after inoculating the reaction mixture with a seeding crystal consist…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.