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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.

The comparative experimental study of Ar–X (X = Cl, Br, I) reactivity and analysis reported herein suggest that oxidative addition cannot be considered the sole reason of the observed low reactivity of aryl chlorides.

The series of novel Pd/NHCF complexes were synthesized via a straightforward approach from fluorine-containing anilines. Computational and structural studies were performed to assess the effect of fluorine on the Pd–NHC bond.

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The mechanism of the C–N cross-coupling reaction, catalyzed by Pd/NHC, was evaluated at the molecular and nanoscale levels. The first evidence for the involvement of a “cocktail”-type system in the Buchwald–Hartwig reaction is provided.

A family of well-defined Λ- and Δ-configured octahedral cationic chiral-at-cobalt catalysts were expanded through a straightforward postcomplexation of the bromine-functionalized Co(III) complexes based on (R,R)-1,2-cyclohexanediamine and (S,S)-1,2-diphenylethylenediamine by Suzuki–Miyaura cross-coupling reaction (CCR) with arylboronic acids. The corresponding modified Co(III) complexes were isolated by standard silica column chromatography with up to 65% yields. Indeed, it is the first example of the direct modification of the ligand sphere of chiral Co(III) catalysts through Suzuki–Miyaura CCR. It was observed for the first time that the chiral metal center is epimerized during the cross-coupling process at the transmetalation stage on palladium catalyst in the case of minor diastereomers of Co(III) complexes (Δ(R,R)-1 and Λ(S,S)-2). Next, the efficacies of obtained chiral metal-templated complexes 1–4 were evaluated in benchmark asymmetric reactions in order to compare their catalytic activity. Chiral Co(III) complexes 1–4 have been examined as hydrogen bond donor (HBD) catalysts in such important reactions as epoxidation of chalcone and the fixation of CO2 into valuable cyclic carbonates.

Dedicated to Prof. Alexandra M. Z. Slawin on the occasion of her 60 th birthday.The influence of fluorination on the acid-base properties and the capacity of structurally related 6-5 bicyclic compounds -1,3-benzodiazole 1, 1,2,3-benzotriazole 2 and 2,1,3-benzoselenadiazole 3 to σ-hole interactions, i. e. hydrogen (1 and 2) and chalcogen (3) bondings, is studied experimentally and computationally. The tetrafluorination increases the Brønsted acidity of the diazole and triazole scaffolds and the Lewis acidity of selenadiazole scaffold decreases the basicity. Increased Brønsted acidity facilitates anion binding via the formation of hydrogen bonds; particularly, tetrafluorinated derivative of 1 (compound 4) binds Cl À . Increased Lewis acidity of tetrafluorinated derivative of 3 (compound 10), however, is not enough for binding with Cl À and F À via chalcogen bonds in contrast to previously studied Te analog of 10. It is suggested that the maximum positive values of molecular electrostatic potential at the σ-holes, V S,max , can be a reasonable metric for design and synthesis of new anion receptors with selenadiazole-diazole/ triazole hybrids as a special target. Related chlorinated compounds are also discussed.