摘要 |
A process for making 2,6-difluorobenzonitrile, comprising reacting 2,6-dichlorobenzonitrile with a substantially anhydrous metal fluoride at a temperature between about 160 DEG C. and about 300 DEG 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. |