Process for producing tetrakis(

1. A process comprising bringing together, in an anhydrous liquid organic medium, either

A) at least one boron trihalide;

at least one F aryl Grignard reagent; and

at least one copper compound,

or

B) at least one boron trihalide;

at least one copper compound;

magnesium metal; and

at least one polyhaloaromatic compound,

to form a halomagnesium tetrakis( F aryl)borate.

2. A process as in claim 1 wherein in B) either

i) at least one boron trihalide, magnesium metal, and at least one copper compound are brought together to form a mixture, and

ii) at least a portion of the mixture formed in i) and at least one polyhaloaromatic compound are brought together;

or

a) at least one copper compound and magnesium metal are brought together to form a mixture, and

b) at least a portion of the mixture formed in a) and a mixture of at least one boron trihalide and at least one polyhaloaromatic compound are brought together.

3. A process as in claim 1 wherein in A),

the copper compound is in an amount that provides about 0.001 mmol or more of copper per mole of F aryl Grignard reagent;

the F aryl Grignard reagent is pentafluorophenyl chloromagnesium, pentafluorophenyl bromomagnesium, heptafluoronaphthyl chloromagnesium, or heptafluoronaphthyl bromomagnesium; and/or

the F aryl Grignard reagent and the boron trihalide are in amounts that provide a molar ratio of about 3.9:1 to about 4.5:1.

4. A process as in claim 1 wherein the copper compound is a copper(I) halide and/or a copper(II) halide.

5. A process as in claim 1 wherein the copper compound is selected from copper(I) chloride, copper(I) bromide, bromotris(triphenylphosphine)copper(I), copper(II) chloride, copper(II) bromide, or mixtures of any two or more of the foregoing.

6. A process as in claim 3 wherein the copper compound is in an amount that provides about 0.001 mmol to about 40 mmol of copper per mole of F aryl Grignard reagent.

7. A process as in claim 1 wherein in B)

the polyhaloaromatic compound is chloropentafluorobenzene, bromopentafluorobenzene, chloroheptafluoronaphthylene, or bromoheptafluoronaphthylene;

the copper compound is in an amount that provides about 0.001 mmol or more of copper per mole of polyhaloaromatic compound; and/or

the polyhaloaromatic compound and the boron trihalide are in amounts that provide a molar ratio of about 3.9:1 to about 4.5:1.

8. A process as in claim 7 wherein the copper compound is in an amount that provides about 0.001 mmol to about 40 mmol of copper per mole of polyhaloaromatic compound.

9. A process as in claim 1 wherein the liquid organic medium is an ether-containing medium, and/or wherein the boron trihalide is boron trifluoride or a boron trifluoride-solvent complex.

10. A process as in claim 1 wherein the boron trihalide is boron trifluoride diethyl etherate complex.

11. A process as in claim 1 wherein the process is conducted at a temperature in the range of about −20° C. to about 60° C.