O-IF₄O- Derivatives of Xenon and Main-Group Elements

Abstract

<p>With improved syntheses of the O-IF₄O- group precursors, HOIOF₄ and IO₂F₃, an extensive derivative chemistry of the O=IF₄O- group has begun to emerge. The xenon(lI) derivatives, FXeOIOF₄ and Xe(OIOF₄)₂, have been shown by their solution ¹⁹F and ¹²⁹Xe NMR spectra to result from the reaction between IO₂F₃ and XeF₂ in SO₂C1F, CFCl₃ and BrF₅ solvents. The covalently bonded O=IF₄O- groups are shown to be equilibrium mixtures of their cis- and trans-isomers and are oxygen bonded to xenon. The solid derivative, cis, cis-Xe(OIOF₄)₂ has been isolated from the acid displacement reaction between Xe(OTeF₅)₂ and the stronger protonic acid mixture cis/trans-HOIOF₄ under neat conditions, or in CFCl₃ solvent. A mixture of the cis and trans-derivatives of FXeOIOF₄ were prepared by the stoichiometric reaction of IO₂F₃ with XeF₂ in anhydrous HF followed by removal of the solvent under vacuum. Both cis/trans-FXeOIOF₄ and cis. cis Xe(OIOF₄)₂ were characterized by ¹⁹F and ¹²⁹Xe NMR spectroscopy and low-temperature Raman spectroscopy. A comparison among ¹²⁹Xe NMR chemical shifts for resulted in an effective group electronegativity order -OSO₂F > trans- O=IF₄O- > -OTeF₅.</p> <p>The thermal decomposition reactions of FXeOIOF₄ and cis. cis-Xe(OIOF₄)₂ have been studied by ¹⁹F NMR spectroscopy and Raman spectroscopy. In the latter case, the novel O=lF₄O- derivative, F₄OIOOIOF₄, has been prepared by the controlled thermal decomposition of cis. cis-Xe(OIOF₄)₂ as well as from the reaction of IO₂F₃ and KrF₂ and characterized by ¹⁹F NMR spectroscopy as the Raman spectroscopy.</p> <p>Higher oxidation state derivatives of xenon were, until the present work, known only for -OTeF₅. The O=IF₄O- derivatives, F₃XeOIOF₄ and OXeF₃OIOF₄, have been identified by ¹²⁹Xe and ¹⁹F NMR spectroscopy as the products of the insertion reactions between IO₂F₃ and XeF₄ and XeOF₄ respectively. In addition, the mixed Xe(VI) derivatives, OXe(OIOF₄)x(OTeF₅)₄_x, resulting from the reaction of HOIOF₄ with OXe(OTeF₅)₄, have been identified in situ by ¹²⁹Xe NMR spectroscopy. The solid product isolated from the neat reaction of HOIOF₄ with OXe(OTeF₅)₄ has been shown by ¹²⁹Xe NMR spectroscopy in solution and Raman spectroscopy in the solid state, to consist of a mixture of cis- and trans-isomers of the novel Xe(VIII) derivative, O₃Xe(OIOF₄)x(OTeF₅)₂_x.</p> <p>Preliminary evidence obtained from Raman spectroscopy as well as ¹¹B and ¹²⁵Te NMR spectroscopy, suggests that novel O-IF₄O- derivatives of boron, mercury and tellurium have also been formed.</p>