Method for the production of tetrakis (pentafluorophenyl) borates

Abstract

A process for preparing tetrakis (pentafluorophenyl) borate is described that involves reaction of a pentafluorophenyl magnesium halide with an alkali metal tetrafluoroborate.

I claim:  
     
       1. A method for the production of tetrakis (pentafluorophenyl) borate which comprises reacting a pentafluorophenyl compound having the formula C 6 F 5 MgX in which X is a halide with an alkali metal salt of tetrafluoroborate in a non-interfering solvent. 
     
     
       2. The  claim 1  method in which the pentafluorophenyl compound is C 6 F 5 MgBr and said alkali metal salt is NaBF 4 . 
     
     
       3. The  claim 1  or  claim 2  method in which said solvent has the formula R—O—R′ in which R and R′ are the same or different aliphatic hydrocarbon groups having 2 to 10 carbon atoms. 
     
     
       4. The  claim 1  or  claim 2  method in which said solvent is ethyl ether. 
     
     
       5. A method which comprises reacting a compound having the formula C 6 F 5 MgX in which X is a halide with a compound having the formula QBF 4  in which Q is sodium, lithium or potassium, 
       said reaction being conducted at a temperature of 0° C. to 100° C. in a solvent being the formula R—O—R′ in which R and R′ are the same or different aliphatic hydrocarbon groups having 2 to 10 carbon atoms to produce a reaction mixture containing a tetrakis (pentafluorophenyl) borate and  
       recovering said tetrakis (pentafluorophenyl) borate from said reaction mixture.  
     
     
       6. The  claim 5  method in which C 6 H 5 MgBr is reacted with NaBF 4  in ethyl ether. 
     
     
       7. The  claim 5  method in which the compound having the formula C 6 H 5 MgX and compound QBF 4  are reacted in an amount which is more than 15% of the stoichiometric amount.