Ionic liquids containing the tetrafluoroborate anion are generally manufactured as follows: in a second step, the halide, e.g., chlorinated or brominated 1-ethyl-3-methylimidazole, can be made to react with NaBF4 in acetone according to the S. Par method; with NaBF4 in water; with AgBF4 or HBF4 in water according to the method; with NH4BF4 in acetone; with HBF4 in methanol; or with microwave irradiation with NH4BF4 to react. However, all known methods have drawbacks, especially for large-scale industrial synthesis.
