Process for the purification of esters of phosphorus thioacids
US4276418A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 28, 1980 |
| Grant date | Jun 30, 1981 |
| Priority date | — |
| Expiry date | Jan 28, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/6512
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the purification of esters of phosphorus thioacids having the formula: ##STR1## wherein R is an organic radical which is attached via a carbon atom thereof to X; PA0 R.sup.1 and R.sup.2 are optionally substituted hydrocarbon radicals which may be the same or different, and PA0 X is O or S, and which contains as an impurity a thiolo isomer having the formula: ##STR2## in which R, R.sup.1, R.sup.2 and X have the previously defined meanings, which comprises washing the ester with an aqueous solution of an acid or an acid salt. Particularly applicable to esters in which R is a substituted pyrimidinyl, phenyl or benzyl radical and R.sup.1 and R.sup.2 are alkyl radicals containing from 1 to 4 carbon atoms, especially methyl or ethyl radicals, which are useful as insecticides.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.