The development and use of superacids in fluorosulfuric acid

231

Cl Fluorine stabilized carbon-sulfur multiple bonding R. Gerhardt, Th. Henkel, A. Klauck, R. Kuschel and K. Seppelt fiir Amganische und Analytische Chemie, Freie Universitiit Berlin (Germany]

Institti

Structural and chemical properties of compounds containing the >C=SF,, \C=SF2=0, \C =SF, and -C=SF, linkages are discussed. The double 6 onded system/sare often quite stable and exhibit true double bond character rather than being ylidic. In a few cases even exo- and endo-cyclic structures exist in ring systems. The triple bonded species are more uncommon, unstable, and show a very soft bending motion, as established by a variety of methods. The range of structures of such triple bonds is considered; chemically they behave as carbenes.

c2 The development acid

and use of superacids in fluorosulfuric

D. Zhang, G. Hwang and F. Aubke University of British Columbia, BC V6T 1ZI (Canada)

2036 Main Mall, Department

of Chemistry,

Vancouver,

Direct metal oxidation by bis(fluorosulfury1) peroxide, Sz06Fz, in the presence of stoichiometric amounts of the corresponding metal fluoride is found to be a convenient method to generate metal fluoride fluorosulfates for use as Lewis acids in either anhydrous HF or HS03F. The latter solvent wiLl be discussed in detail. The one step synthesis proceeds according to the general equation: nMF, + (5 - n)M + excess S206F2 -----+ 1-4 days n=O

to 5, M=Nb,

5MF,(SO,F),-,

Ta or Sb

The resulting products are viscous liquids, with their thermal stability decreasing with increasing S03F content, due to SO, elimination: MF,(SO,F),-,

-

MF,+,(SO,F),-,+SO,

They are miscible with HSOBF in any proportion. Electrical conductivity and Han-met function studies will be reported. As an example the generation and characterization of the unusual square in superacid media will be discussed. planner cation [Pt(C0)4]2+

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