Other compounds of xenon

For Xe(II), a linear coordination environment is typical and in the solid state, salts containing [XeF], [XeOTeFs] or related cations exhibit significant cation—anion 

Xenon-carbon bond formation is now well exemplified, and many products contain fiuorinated aryl substituents, e.g. (QF5C02)Xe(QF5), [(2,6-F2C5H3N)XeQF5] + 

The [CfiF5XeF2] ion (formed as the [BF4] salt from C6F5BF2 and XeF4, see worked example 18.1) is an extremely powerful oxidative-fluorinating agent, e.g. it converts I2 to IF5. 

The use of a difluoroborane, RBF2, precursor has proved to be a successful strategy for alkyl, alkenyl and aUcynyl derivatives of xenon(II). Xenon-carbon(alkene) and Xe-C(alkyne) bond formation is illustrated by reactions 18.20 and 18.21. 

Compounds containing linear C—Xe—Cl units are recent additions to xenon chemistry, the first examples being C6F5XeCl (equation 18.22) and [(C6F5Xe)2Cl] (equation 18.23 and structure 18.16). 

Compounds containing metal-xenon bonds have been known only since 2000. The first example was the square 

The +2 oxidation state is rare for gold (see Section 22.12). The acid strength of the HF/SbF5 system can be lowered by reducing the amount of SbF5 relative to HF. Under these conditions, crystals of the Au(III) complex 17.16 

The first detection of compounds containing metal-xenon bonds (Fe(CO)4Xe and M(CO)5Xe with M = Cr, Mo, W) was in the 1970s and involved matrix isolation studies. Since 2000, a number of fully isolated and characterized compounds containing Au-Xe or Hg-Xe bonds have been known, but even the most stable of these compounds decomposes at 298 K with loss of Xe. Their isolation depends upon the solvent and counter-ion being a weaker base than Xe(0). The first example was the square planar [AuXe4] cation (av. Au—Xe = 275 pm). It is produced when AuFy is reduced to Au(II) in anhydrous HF/SbF5 in the presence of Xe (eq. 18.24). 

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

Some oxides of xenon are known, and like most other compounds of xenon they are usually obtained from the fluorides. Two reactions that yield Xe03 have already been shown in Eq. (15.237)... 

In the 1960s, scientists first produced compounds of xenon and some other noble gases at the Argonne National Laboratory located near Chicago. Xenon and krypton are the only noble gases that readily form compounds with oxygen and fluorine. For instance, when xenon combines with fluorine, it can form a series of compounds, such as xenon difluoride PCeF ), xenon tetra-fluoride (XeF ), and xenon hexafluoride pCeF ). These and other compounds of xenon are formed within metal containers at high temperatures and pressures. They are not stable. 

All other compounds of xenon are made from xenon fluorides. 

Let s work two examples illustrating the steps necessary to produce a good Lewis structure. We will take HN02 and XeF4 for these examples. The first molecule is nitrous acid. It is an example of an oxyacid. (Oxyacids are compounds containing hydrogen, oxygen, and one other element.) The other compound is xenon tetrafluoride. 

Xenon reacts directly with fluorine to form fluorides. Other compounds of Xe can be prepared by reactions using xenon fluorides as starting materials, which fall into four main types ... 

Not only were the fluorides the first compounds of xenon to be prepared, but also they serve as starting materials for the synthesis of most other xenon compounds. Xenon difluoride can be prepared by the reaction of excess xenon with fluorine aided by heat or electromagnetic radiation ... 

The other noble-gas elements form compounds much less readily than xenon. For many years, only one binary krypton compound, Krp2, was known with certainty, and it decomposes to its elements at —10 °C. Other compounds of krypton have been isolated at very low temperatures (40 K). 

The chemistry of xenon is much more extensive than that of any other noble gas. Only one binary compound of krypton. KrF2, has been prepared. It is a colorless solid that decomposes at room temperature. The chemistry of radon is difficult to study because all its isotopes are radioactive. Indeed, the radiation given off is so intense that it decomposes any reagent added to radon in an attempt to bring about a reaction. 

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