Solventless process for making 2,6 difluorobenzonitrile
US5502235A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1994 |
| Grant date | Mar 26, 1996 |
| Priority date | — |
| Expiry date | Dec 28, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C253/30
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for making 2,6-difluorobenzonitrile, comprising reacting 2,6-dichlorobenzonitrile with a substantially anhydrous metal fluoride at a temperature between about 160.degree. C. and about 300.degree. C. and in the presence of a phase transfer catalyst, which is typically a polyether, tetra-substituted phosphonium salt, tetra-substituted ammonium salt, and cryptand, but in the absence of a solvent. After taking off the product the resulting mixture may be recycled into the reactor for the next reaction cycle. Upon build-up of tars in the reaction process, the invention includes the separation of catalyst from the tars and the recycle thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.