Syntheses and Structures of F₆XeNCCH₃ and F₆Xe(NCCH₃)₂

Abstract

Acetonitrile and the potent oxidative fluorinating agent XeF 6 react at À40 8 8Ci nF reon-114 to form the highly energetic, shock-sensitive compounds F 6 XeNCCH 3 (1)a nd F 6 Xe(NCCH 3 ) 2 ·CH 3 CN (2·CH 3 CN). Their low-temperature single-crystal X-rays tructures show that the adducted XeF 6 molecules of these compounds are the most isolated XeF 6 moieties thus far encountered in the solid state and also providet he first examples of Xe VI ÀNb onds.T he geometry of the XeF 6 moiety in 1 is nearly identical to the calculated distorted octahedral (C 3v )geometry of gas-phase XeF 6 .The C 2v geometry of the XeF 6 moiety in 2 resembles the transition state proposed to account for the fluxionality of gas-phase XeF 6 . The energy-minimized gas-phase geometries and vibrational frequencies were calculated for 1 and 2,a nd their respective binding energies with CH 3 CN were determined. The Raman spectra of 1 and 2·CH 3 CN were assigned by comparison with their calculated vibrational frequencies and intensities.

A Stable Crown Ether Complex with a Noble‐Gas Compound

“…The strong oxidant properties of noble-gas fluorides,o xide fluorides,and oxides render the syntheses of isolable organic noble-gas compounds particularly challenging.T he XeÀN bonded XeF 6 adducts of the oxidatively resistant acetonitrile ligand, F 6 XeNCCH 3 and F 6 Xe(NCCH 3 ) 2 ,h ave been synthesized and structurally characterized at low temperatures,b ut both compounds are highly energetic and shock-sensitive. [1] Xenon trioxide,ap otent oxidizer that rapidly oxidizes primary and secondary alcohols to CO 2 and H 2 Oi na queous media, [2][3][4] has marginal kinetic stability in the solid state and readily detonates when subjected to slight thermal or mechanical shock, liberating Xe and O 2 gases and 402 AE 8kJmol À1 of energy. [5] Unlike XeF 6 ,a dduct formation between XeO 3 and aL ewis base can dramatically reduce the shock sensitivity of XeO 3 ,a si llustrated by O 3 Xe-(NCCH 3 ) 2 [6] and (C 5 H 5 N) 3 XeO 3 , [7] which are stable at room temperature and are shock-insensitive.T he XeO 3 molecules in the three known phases of solid XeO 3 are extensively crosslinked through weakly covalent intermolecular Xe---Oc ontacts that have been ascribed to s-hole bonding.…”

Coordination of KrF2 to a Naked Metal Cation, Mg2+

“…Noble‐gas chemistry has continued to provide new compounds having interesting structures and bonding modalities since the discovery of xenon reactivity over a half century ago . The number of crystallographically characterized xenon compounds presently exceeds 150 and spans the + , +2, +4, +6, and +8 oxidation states of xenon, whereas those of krypton number eleven.…”