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The reported synthesis of the H2OF+ cation as a product of the oxidative fluorination of H2O by [XeF][PnF6] (Pn = As, Sb) in HF solution has been reinvestigated. The system exhibits complex equilibria, producing two new Xe(II) compounds, [Xe3OF3][PnF6] and [H3O][PnF6]2XeF2, refuting the original claim for the synthesis of the H2OF+ cation. Both compounds have been isolated and characterized by vibrational spectroscopy and single-crystal X-ray diffraction. The X-ray crystal structures of the [Xe3OF3][PnF6] salts contain the Z-shaped FXeOXeFXeF+ cation, which represents the first example of an isolated Xe(II) oxide fluoride. The crystal structure of the [H3O][AsF6]2XeF2 adduct contains XeF2 molecules that interact with the H3O+ cations. The vibrational assignments for the Xe3OF3+ cation have been made with the aid of quantum-chemical calculations and were confirmed by (sup 18)O-enrichment, while the assignments for [H3O][AsF6]2XeF2 were confirmed by 2D- and (sup 18)O-enrichment. Quantum-chemical calculations have also been carried out for H3O+nXeF2 (n = 14), and have been used to interpret the X-ray crystal structure and vibrational spectra of [H3O][AsF6]2XeF2. The energy-minimized geometries and vibrational frequencies for HOF and H2OF+ have been calculated, further disproving the original report of the H2OF+ cation. Both FXeOH and FXeOH2+ have also been computed and are viable intermediates in the proposed equilibria between XeF+ and H2O that lead to the Xe3OF3+ cation., Submitted for publication in the Journal of the American Chemical Society. Prepared in collaboration with McMaster University, Hamilton, Ontario and the University of Southern California, Los Angeles, CA.

The novel bis?bis(trifluoromethyl)phosphanido !argentate, Ag(P(CF3)2!2(-), is obtained via the reaction of HP(CF3)2 with Ag(CN)2(-) and isolated as its K(18-crown-6) salt. If the cyclic phosphane (PCF3)4 is reacted with a slight excess of K(18-crown-6)Ag?P(CF3)2!2 a selective insertion of one PCF3 unit into each silver phosphorus bond is observed, giving NMR spectroscopic evidence for the Ag?P(CF3)P(CF3)2!2(-) ion. On treatment of the phosphane complexes M(CO)5PH(CF3)2 (M= Cr, W) with K(18- crown-6)Ag(CN)2 the formation of the comparable trinuclear argentates, Ag?(mu P(CF3)2)M(CO)5!2(-) is achieved. The chromium compound K( 18-crown-6) Ag((mu P(CF3)2)Cr(CO)5!2 crystallizes in a non-centrosymmetric space group Fdd2 (no. 43), a = 2970.2(6) pm, b = 1584.5(3) pm, C = 1787.0(4), V = 8.410(3)cu nm, Z= 8. The C2 symmetric anion, Ag?(mu-P(CF3)2)Cr(CO)5!2(-), shows a nearly linear arrangement of the P-Ag-P unit and represents the first example of a structurally characterized perfluorinated phosphanido-metal complex. Although, the bis(pentafluorophenyl)phosphanido compound Ag?P(C6F5)2!2(-) could not be obtained so far, the synthesis of its trinuclear counterpart, K(18-crown-6) Ag ? (mu-P(C6F5)2)W(CO)5! 2! was successful., Prepared in cooperation with Institut fuer Anorganische Chemie, Universitaet zu Koeln, Germany.

When reacted with an excess of the corresponding carbonyl halides, AsF5 and SbF5 from the following 1:1 adducts: COCl2*AsF5, COCl2*SbF5, COCIF*AsF5, COClF*SbF5, COF2*AsF5 and COF2*SbF5. All adducts are unstable at ambient temperature, and their dissociation enthalpies were determined from the dissociation pressure curves. Vibrational and multinuclear NMR spectra and theoretical calculations show that all compounds are oxygen-coordinated donor-acceptor adducts, and that the strengths of the oxygen-bridges increase from COF2 to COCl2 and from AsF5 to SbF5.