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Библиогр.: 35 назв.

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 Brønsted acidity of diazole and triazole scaffolds and Lewis acidity of selenadiazole scaffold and decreases basicity. Increased Brønsted acidity facilitates anion binding via the formation of hydrogen bonds; particularly, tetrafluorinated derivative of 1 (compound 4) binds Cl–. Increased Lewis acidity of tetrafluorinated derivative of 3 (compound 10), however, is not enough for binding with Cl– and F– via the formation of 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, VS,max, can be reasonable metrics in the further design and synthesis of new anion receptors, with selenadiazole–diazole / triazole hybrids as a special target. Related chlorinated compounds are also discussed. Introduction Design and synthesis of new anion receptors functioning via various σ-hole interactions,[1] e.g. hydrogen and chalcogen bondings (Brønsted and Lewis acidity, respectively), attract much current attention, particularly due to potential biomedical, technological and environmental applications.[2-4] Effective tool in the field is polyfluorination, for (hetero) aromatics affecting many properties significant for chemistry, materials science and biomedicine, including a capacity to σ-hole interactions.[1,5-9] Structurally-related, 1,2-diaminobenzene-derived, 1,3- benzodiazole (benzimidazole) 1, 1,2,3-benzotriazole 2, and 2,1,3-benzoselenadiazole 3, already having numerous applications in current chemistry, materials science and biomedicine,[7,10] are appropriate targets for studying effects of polyfluorination on Brønsted (1 and 2) and Lewis (3) acidity and anion-binding properties (Scheme 1).