Process for making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole using methyldithiocarbazinate with trifluoroacetic acid with selective removal of 2,5-bis(methylthio)-1,3,4-thiadiazole
US6034245A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1998 |
| Grant date | Mar 7, 2000 |
| Priority date | — |
| Expiry date | Dec 18, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a process for making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole. The process includes the steps of reacting methyidithiocarbazinate with trifluoroacetic acid, in the absence of phosphorus trichloride, to form a mixture of 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole and 2,5-bis-(methylthio)-1,3,4-thiadiazole. Further, the process of the present invention includes selectively removing the 2,5-bis-(methylthio)-1,3,4-thiadiazole by acidifying the reaction mixture, and then separating the aqueous and organic phases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.