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The chemistry of carbon−xenon compounds is one of the newest in the field of organoelement chemistry. The specific character of carbon−xenon chemistry can be ascribed to the fact that in all XeII and XeIV compounds hypervalent bondssymmetrical or asymmetricalwith a high partial positive charge on Xe are present. Different from the class of high-oxidation-state organometallic derivatives of d metals, C−Xe compounds have low coordination numbers and, additionally, contain three or two lone electron pairs. It is the intent of this review to present the still limited number of synthetic approaches to C−Xe compounds and to organize their presently known reactivities into categories. It is hoped that C−Xe compounds can be introduced in the future as precursors in synthetic organic and organoelement chemistry.

Polyfluorinated phenyl(dihydroxy)boranes C 6 H 5-n F n B-(OH) 2 (n ϭ 3 Ϫ 5) underwent hydrodeboration (formal replacement of the (dihydroxy)boryl group by hydrogen) in the presence of bases (MeOH, 33 % H 2 OϪMeOH, KOH (1 equiv.)/33 % H 2 OϪMeOH, pyridine and 9 % D 2 OϪpyridine) and formed the fluoroaromatic compounds ArH or ArD, respectively. The rate of Polyfluororganische Bor-Sauerstoff Verbindungen. 2 [1] Die Hydrodeborierung von Polyfluorphenyl(dihydroxy)boranen unter basischen Bedingungen.Inhaltsübersicht. Polyfluorierte Phenyl(dihydroxy)borane C 6 H 5-n F n B-(OH) 2 (n ϭ 3 Ϫ 5) unterliegen in Gegenwart von Basen (MeOH, 33 % H 2 OϪMeOH, KOH (1 Äquiv.)/33 % H 2 OϪMeOH, Pyridin und 9 % D 2 OϪPyridin) einer Hydrodeborierungsreaktion (formaler Ersatz der (Dihydroxy)borylgruppe durch Wasserstoff) und bil-* Prof. reaction depends on the number of fluorine atoms in the phenyl group and on the position of the fluorine atoms, relative to the B(OH) 2 substituent.

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Currently, the chemistry of organofluorine compounds is a leading and rapidly developing area of organic chemistry. Fluorine present in a molecule largely determines its specific chemical and biological properties. This thematic issue covers the trends of organofluorine chemistry that have been actively developed in Russia the last 15 – 20 years. The review describes nucleophilic substitution and heterocyclization reactions involving fluorinated arenes and quinones and skeletal cationoid rearrangements in the polyfluoroarene series. The transformations involving CF3-substituted carbocations and radical cations are considered. Heterocyclization and oxidative addition reactions of trifluoroacetamide derivatives and transformations of the organic moiety in polyfluorinated organoboranes and borates with retention of the carbon – boron bond are discussed. Particular attention is devoted to catalytic olefination using freons as an efficient synthetic route to fluorinated compounds. The application of unsymmetrical fluorine-containing N-heterocyclic carbene ligands as catalysts for olefin metathesis is demonstrated. A variety of classes of organofluorine compounds are considered, in particular, polyfluorinated arenes and 1,2-diaminobenzenes, 1-halo-2-trifluoroacetylacetylenes, α-fluoronitro compounds, fluorinated heterocycles, 2-hydrazinylidene-1,3-dicarbonyl derivatives, imines and silanes. The potential practical applications of organofluorine compounds in fundamental organic chemistry, materials science and biomedicine are outlined. The bibliography includes 1019 references.