Patent ID: 6580007
Filing Date: 2003-06-17
Classification: C07F

Abstract:
A process for the preparation of potassium tetrakis(pentafluorobenzene)borate in a reactor, comprising the following steps:(a) adding anhydrous butyl ether and pentafluorobenzene into the reactor to obtain a reaction mixture, and, then, mixing with stirring the reaction mixture while cooling to a temperature of about âˆ’70Â° C., to obtain a step (a) reaction mixture, (b) running a solution of alkyllithium into the step (a) reaction mixture at a controlled rate, to obtained a step (b) reaction mixture, (c) adding BR3, undissolved beforehand, to the step (b) reaction mixture, wherein the R groups, identical or different, are a chlorine atom, a fluorine atom, a bromine atom or an alkoxy radical comprising between 1 and 4 carbon atoms, and rising the temperature to about 0Â° C., to obtain a step (c) reaction mixture, (d) adding an aqueous potassium chloride solution to the step (c) reaction mixture, and then stirring at ambient temperature, to obtain a step (d) reaction mixture, (e) settling the step (d) reaction mixture to obtain an aqueous phase and an organic phase, withdrawing said aqueous phase, adding a potassium chloride solution to the organic phase and, then, distilling the organic phase under a reduced pressure, to obtain potassium tetrakis(pentafluorophenyl)borate, and (f) recovering after filtering the potassium tetrakis(pentafluorophenyl)borate obtained in step (e).