Xenon dioxide difluoride

Although uncontrolled reaction of xenon hexafluoride and moisture produces explosive xenon trioxide, controlled action by progressive addition of limited amounts of water vapour with agitation to a frozen solution of the hexafluoride in anhydrous hydrogen fluoride at —196° C to give xenon oxide tetrafluoride or xenon dioxide difluoride is safe [1], Controlled hydrolysis in solution in hydrogen fluoride is, however, described as hazardous [2],... 

Xenon Dioxide Difluoride. Xe02F2 mw 201.30 colorl solid, liq vap mp 30.80°.Prepn is by distilling Xe oxytetrafluoride into Xe trioxide at dry ice temp, and then fractionally distilling off the unreacted Xe oxytetrafluoride along with the by-product Xe difluoride, leaving the product. According to Holloway, samples of Xe dioxide-difluoride have expld Refs 1) J.H. Holloway, Noble Gas Chemistry , Methuen, London (1968), 132-34 2) J.C. 

Xe02p2 was observed in the early mass spectra of xenon fluorides and can be obtained by hydrolysis of XeFe. The best method for its preparation in macroscopic quantities is by the reaction of XeOs and XeOp4. The XeOp4 and Xep2 impurities may be removed by fractional distillation. Xenon dioxide difluoride forms colorless crystals at room temperature, which have a vapor pressure between that of XeOs and XeOp4 and melts at 303.95 K to give a colorless liquid. It can decompose to Xep2 and O2. 

In view of the instability of the trioxide it is interesting to speculate on the stability of the oxyfluorides. Xenon oxide tetrafluoride should be an exothermic compound since the atomic heat of formation using average bond energies of 32 kcal. and 17 kcal. respectively for Xe-F and Xe-O is —160 kcal. mole-. The combined heat of atomization of four fluorine atoms (4 x 18.3 kcal.) and one oxygen atom (59.2 kcals.), 132.4 kcal., is less than this. Xenon dioxide difluoride, by such considerations, should be endothermic. It is of interest that xenon oxide tetrafluoride is easily made by controlled hydrolysis of xenon hexafluoride and is a thermally stable entity (m.p. —28) whereas xenon dioxide difluoride has been observed only mass spectrometrically < >. 

The pure, crystalline chromium (V) oxide trifluoride can be prepared by the reaction of xenon(II) difluoride and chromium (VT) dioxide difluoride [7788-96-7], also known as chromyl fluoride, Cr02F2 (56) ... 

Xenon Trioxide Difluoride and Xenon Dioxide Tetrafluoride... 

In the preparation of xenon difluoride dioxide from caesium nitrate and xenon tetrafluoride oxide, the latter must always be used in excess to prevent formation of explosive xenon trioxide. 

In the reaction of the pentaoxide with xenon tetrafluoride oxide to give xenon difluoride dioxide and nitryl fluoride, the xenon tetrafluoride oxide must be used in excess to avoid formation of xenon trioxide, which forms a sensitive explosive mixture with xenon difluoride dioxide. 

Oxidative Fluorination of Nitrones to a-Fluorosubstituted Nitroxyl Radicals Formation of nitroxyl radicals by the radical cation route was observed in reactions of various nitrones with xenon difluoride in dry methylene chloride (520, 523). In this reaction, more than 40 nitrones, including 4H -imidazole N,N -dioxides (219), 4H -imidazole TV-oxides (223) and (224), 2H -imidazole N -oxides (225), 2H -imidazole TV,TV-dioxides (226), 3,3,5,5-tetramethylpyrroline N -oxide (TMPO), derivatives of 3-imidazoline-3-oxides (231) and (232), have been examined. ESR spectra of nitroxyl radicals containing one or two fluorine atoms at a-C have been registered (Scheme 2.108) (523). In the case of... 

Tungsten tetrabromide oxide, 0294 Undecaamminetetraruthenium dodecaoxide, 4598 Xenon difluoride dioxide, 4322 Xenon tetrafluoride oxide, 4346 Zinc ethylsulfinate, 1711... 

Krypton difluoride, 4313 Potassium hexaoxoxenonate-xenon trioxide, 4674 Tetrafluoroammonium hexafluoroxenate, 4386 Xenon difluoride dioxide, 4322 Xenon difluoride oxide, 4319 Xenon difluoride, 4332 Xenon hexafluoride, 4377 Xenon tetrafluoride, 4353 Xenon tetrafluoride oxide, 4346 Xenon tetraoxide, 4863 Xenon trioxide, 4857 Xenon(II) fluoride methanesulfonate, 0443 Xenon(II) fluoride perchlorate, 3977 Xenon(II) fluoride trifluoroacetate, 0634 Xenon(II) fluoride trifluoromethanesulfonate, 0356 Xenon(IV) hydroxide, 4533 Xenon(II) pentafluoroorthoselenate, 4382 Xenon(II) pentafluoroorthotellurate, 4383 Xenon(II) perchlorate, 4110 See Other NON-METAL HALIDES, NON-METAL OXIDES... 

The application of VSEPR theory to triatomic molecules is exemplified by considering water, carbon dioxide, xenon difluoride and a trio of connected species the nitronium ion, N02+, nitrogen dioxide and the nitrite [or nitrate(III)] ion, N02. ... 

At ambient temperature xenon difluoride is very soluble in hydrogen fluoride, bromine trifluoride, iodine pentafluoride, sulfur dioxide, sulfuryl chloride fluoride, acetonitrile it is... 

As a rule xenon difluoride does not react with alkanes. Methane is oxidized by a water solution of xenon difluoride under high pressure (3.8 x 104"— 15.2 x 104 Torr) at 10-25 C in a special high-pressure reactor to form a mixture of methanol (4-8%), fluoromethane (1-2%) and carbon dioxide (25-50%).12... 

Xenon difluoride dioxide cannot be Isolated as an Intermediate between the partial hydrolysis to form XeOF4 and complete hydrolysis to Xe03. bin may be prepared by combining these two species ... 

Keywords nitroxyl, verdazyl, nitrogen dioxide, bromine, xenon difluoride, gas-solid reaction... 

Xenon difluoride dioxide, 4316 Xenon difluoride oxide, 4313 Xenon difluoride, 4326 Xenon hexafluoride, 4371 Xenon(II) fluoride methanesulfonate, 0442 Xenon(II) fluoride perchlorate, 3971 Xenon(II) fluoride trifluoroacetate, 0630 Xenon(II) fluoride trifluoromethanesulfonate, 0355 Xenon(II) pentafluoroorthoselenate, 4376 Xenon(II) pentafluoroorthotellurate, 4377 Xenon(IV) hydroxide, 4528 Xenon tetrafluoride oxide, 4340 Xenon tetrafluoride, 4347 Xenon tetraoxide, 4857 Xenon trioxide, 4851 Xenon, 4920 t mixo-Xylene, 2964 t m-Xylene, 2966 t o-Xylene, 2965 t p-Xylene, 2967... 

Xenon difluoride reacts also with some halosubstituted alkanes18,19 at room temperature in chloroform, carbon tetrachloride, dichloromethane or bromoform, and depending on the nature of the solvent used chloro or bromo derivatives are isolated with imidazo-(l,2-fr)-pyridazine18. Carbon tetrachloride reacts with xenon difluoride at 180°C, while room-temperature transformations are achieved when various catalysts [antimony trifluoride, tantalum(V) fluoride or silica dioxide] are used, whose structure also influences the product distribution20. Tris(fluorosulfonyl)methane gives a fluoro-substi-tuted product in its reaction with xenon difluoride in difluorodichloromethane21. 

Potassium hexaoxoxenonate-xenon trioxide, 4674 Tetrafluoroammouium hexalluoroxenate, 4386 Xenon difluoride dioxide, 4322... 

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