Dioxygenyl hexafluoroarsenate

Hexa/luorobenzene, perfluoromethylbcnzene, and octafluoronaphthalene are oxidized to the corresponding cation salts by dioxygenyl hexafluoroarsenate [45] (equation 38) Salts of monocyclic perlluoroaromatics are unstable above 15 °C, whereas that of octafluoronaphthalene is indefmitely stable at room temperatures... 

Glemser and Smalc798 have prepared the compound Br 1 AsFfi by the displacement of oxygen in dioxygenyl hexafluoroarsenate by bromine [Eq. (4.196)] and by the reaction of bromine pentafluoride, bromine, and arsenic pentafluoride [Eq. (4.197)]. The compound is chocolate-brown and in solution has absorption bands at 310 nm and 375 nm it has fair thermal stability and can be sublimed at 30-50°C under nitrogen atmosphere. 

The C)2 1 Sh2I i i was converted to 02+SbI fi by heating at 130°C in vacuo conversely, 02+Sb2Fn- was prepared by reaction of 02 1 SbFfi and SbF5 at 180-200°C. Dioxygenyl hexafluoroarsenate is markedly less stable than the hexafluoroantimonate salts it decomposes rapidly at 130-180°C. 02 1 PtF(, can be sublimed above 90°C in vacuo and melts with some decomposition at 219°C in a sealed tube.863... 

Also, a compound containing the Br3+ cation is obtained by a reaction of bromine with dioxygenyl hexafluoroarsenate(V), 02AsF6. The reaction can be represented as follows ... 

Glemser and Smalc (15) have prepared the compound Brg+AsFg" by the displacement of oxygen in dioxygenyl hexafluoroarsenate by bromine [Eq. (12)] and by the reaction of bromine pentafluoride,... 

Dioxygenyl hexafluoroarsenate can be prepared by the reaction between arsenic pentafluoride and dioxygen difluoride or by heating a mixture of arsenic pentafluoride, fluorine, and oxygen. However, photosynthesis, using this latter mixture, appears to be the most convenient method for the preparation of dioxygenyl hexafluoroarsenate. 

Dioxygenyl hexafluoroarsenate is a white, loose, nonvolatile powder. It is stable at room temperature, but above 100°C it decomposes rapidly. It hydrolyzes readily, and therefore should be handled in a dry box. 

Peroxydisulfuryl fluoride is usually synthesized by catalytic fluorination of sulfur trioxide.However, pure peroxydisulfuryl fluoride can be obtained in a relatively simple way by the reaction between fluorosulfuric acid and dioxygenyl hexafluoroarsenate. The method lends itself to preparation of smaller quantities (a few grams) of peroxydisulfuryl fluoride. The reaction can be carried out in an openable nickel or Monel pressure vessel, into which dioxygenyl hexafluoroarsenate is transferred from a photochemical reactor (see the preceding synthesis of dioxygenyl hexafluoroarsenate) or, more simply, in the same Pyrex-glass flask in which dioxygenyl hexafluoroarsenate has previously been synthesized. 

About 10 g of fluorosulfuric acid is condensed into an evacuated flask containing dioxygenyl hexafluoroarsenate cooled to — 196°C and warmed upto room temperature. The products are pumped through three traps, cooled to 0, — 78, and — 196°C, respectively. In the first trap unreacted... 

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