A detailed account of a convenient lab-scale preparation of AsF5 via direct fluorination of AsF3

A short summary is given of different preparative routes to the important fluorinating and oxidizing agent arsenic pentafluoride (AsF5). Among the useful preparative routes to AsF5 the fluorination of AsF3 has many advantages. The reaction is less exothermic than that starting from arsenic metal and thus safer, the usage of F2 is minimized (only one equivalent F2 per produced equivalent AsF5 is needed), and a separation from by-products is not necessary. Complete preparative details are presented for the synthesis of AsF5 from AsF3 and F2 at high pressure in a Monel reaction vessel and for the synthesis of the precursor AsF3 from CaF2, As2O3 and H2SO4.