Xenon reactions

Thus in xenon reaction (10) should be considered as electron attachment to a pyrazine molecule that already has a cluster of xenon atoms around it. 

The non-linear nature of the neutron-xenon reaction and the time delays in this second-order system are such as to promote a tendency for fluctuations of reactor power. Generally this is easily dealt with by an overall control system adjusting absorbing rods, since the time scale is of tens of hours. 

The reaction path shows how Xe and Clj react with electrons initially to form Xe cations. These react with Clj or Cl- to give electronically excited-state molecules XeCl, which emit light to return to ground-state XeCI. The latter are not stable and immediately dissociate to give xenon and chlorine. In such gas lasers, translational motion of the excited-state XeCl gives rise to some Doppler shifting in the laser light, so the emission line is not as sharp as it is in solid-state lasers. 

Del y for Dec y. Nuclear power plants generate radioactive xenon and krypton as products of the fission reactions. Although these products ate trapped inside the fuel elements, portions can leak out into the coolant (through fuel cladding defects) and can be released to the atmosphere with other gases through an air ejector at the main condenser. 

K [14881-07-3], Rb [72151 -96-3], and Cs [72138-72-8]), are prepared by reaction of elemental fluorine, chlorine trifluoride, or xenon difluoride and a mixture of nickel fluoride and alkaH metal fluorides or other metal haHdes (16,17). If the fluorination is carried out using mixed fluorides, a lower temperature can be used, yields are quantitative, and the final products are of high purity. Bis(tetrafluoroammonium) hexafluoronickelate [6310540-8], (NE 2N iF6> prepared from Cs2NiF3 and NE SbE by a metathesis in anhydrous HE, is also known (18). 

Oxides. Two oxides of xenon are known xenon trioxide [13776-58-4], XeO, and xenon tetroxide [12340-14-6], XeO (Table 1). Xenon trioxide is most efftcientiy prepared by the hydrolysis of XeE (47) or by the reaction of XeE with HOPOE2 (48). The XeO molecule has a trigonal pyramidal shape Xe—O, 176(3) pm (49), and XeO is tetrahedral with Xe—O, 173.6(2) pm (50). Xenon tetroxide is prepared by the interaction of concentrated sulfuric acid with sodium or barium perxenate, Na XeO, Ba2XeO ( )- Both oxides are thermodynamically unstable, explosive soHds which must be... 

Krypton difluoride cannot be synthesized by the standard high pressure-high temperature means used to prepare xenon fluorides because of the low thermal stabitity of KrF. There are three low temperature methods which have proven practical for the preparation of gram and greater amounts of KrF (141—143). Radon fluoride is most conveniently prepared by reaction of radon gas with a tiquid halogen fluoride (CIE, CIE, CIE, BrE, or lE ) at room temperature (144,145). 

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) ... 

Reactions of Organic Compounds with Xenon Huondes Filler, R Isr J Chem 17, 71-79 56... 

Trimethylarsine gives a 98% yield of trimethylarsine difluoride when treated with xenon difluoride [102] in fluorotrichloromelhane. and tnsfpentafluorophen-yl)arsine gives a 94% yield of tris(pentafluornphenyl)arsme difluoride after reaction with dilute fluorine in fluorotnchloromethane at 0 C [106] Other trivalent arsenic compounds have also been fluorinated with xenon difluoride [103] In addition, arsines have been oxidatively fluorinated by iodine pentafluoride [107] or electrochemically in 26-34% yield [108]... 

Xenon difluoride [4, 5, 7, 8,10] is a white crystalline material obtained through the combination of fluorine and xenon m the presence of light The reagent is commercially available and possesses a relatively long shelf-life when stored cold (freezer) Xenon difluoride is very effective for small-scale fluormation of alkenes and activated nucleophilic substrates. The reactions are usually conducted between 0 °C and room temperature in chloroform or methylene chloride solutions Hydrogen fluoride catalysis is sometimes helpful Xenon difluoride reacts in a manner that usually involves some complexation between the substrate and reagent followed by the formation of radical and radical cation intermediates... 

Carboxylic acids react with xenon difluoride to produce unstable xenon esters The esters decarboxylate to produce free radical intermediates, which undergo fluonnation or reaction with the solvent system Thus aliphatic acids decarboxylate to produce mainly fluoroalkanes or products from abstraction of hydrogen from the solvent Perfluoro acids decarboxylate in the presence of aromatic substrates to give perfluoroalkyl aromatics Aromatic and vinylic acids do not decarboxylate [91] (equation 51)... 

Xenon difluoride reaction with nitro enolates provides a useful entry into a wide variety of fluonnated synthetic intermediates [91 92] (equation 52)... 

Silyl enol ethers are fluonnated in high yields with xenon difluoride [62 93, 94 95] Applications of this reaction to the preparation of fluonnated... 

Xenon difluoride fluorinates adamantane in low yield [45] (equation 22) When the carbon-hydrogen bond is activated by an a-sulfur atom, fliiorination occurs readily The reactions involve intermediates that contain sulfur-fluorine bonds. At-Fluoropyridinium reagents behave similarly [99, 100, 101, 102] (equations 55-57)... 

It is from the binary fluorides that other compounds of xenon are invariably prepared, by reactions which fall mostly into four classes ... 

Any combination of reaction products consistent with these conseiwation principles is possible. For example, in the neutron-induced nuclear fission of it is possible to produce Xe, Sr, two neutrons, and 185 MeV of energy. The most likely reaction products are close in atomic number to xenon pCe) and strontium (Sr), but the possibilities number in the hundreds. 

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