Displacement of Lewis Acid Gases - PF₅, BF₃ and SiF₄ from Their Ammonium, Alkali Metal and Pyridinium Fluorocomplexes by Sulphur Trioxide at Room Temperature

Abstract

Lewis acid gases, PF₅, BF₃ and SiF₄ are liberated from their ammonium, alkali metal and pyridinium fluorocomplexes, NH₄PF₆, NaPF₆, KPF₆, C₅H₅NHPF₆, C₅H₅NHBF₄ and (C₅H₅NH)₂SiF₆, when treated with sulphur trioxide at room temperature. The dissociated ammonium/alkali metal fluorides as well as the pyridinium fluoride react further with the excess sulphur trioxide to form the corresponding fluorosulphates. The products, Lewis acid gases and the fluorosulphates, have been 19 characterised by I. R., F NMR and wet chemical analysis. This is the first report of the synthesis of these gases from pyridinium fluorosulphate at room temperature in good yields.