Реферат: Tellurium-based chalcogen bonds (ChB) are among the most appealing non-covalent interactions that include heavy elements. These ChBs are noticeably stronger as compared to those with sulfur or selenium, and can allow for much more versatile structural chemistry to be studied. In 1,2,5-telluradiazoles (TeD) and benzo-fused derivatives, the Te atom can form one or two chalcogen bonds, thus leading to oligomers or polymeric structures. Energies of these Te–X ChBs (calculated at 1–10 kcal/mol)1 make it possible to form stable complexes with- different types of donors (e. g. X = halogenides, chalcogenolates, neutral N- or C-donors), possessing molecular or polymeric structures.2 Nitrogen atoms of the TeD ring can also form „classical“ coordination bonds with acceptors (such as BPh3). One of consequences is the [Te2N2] secondary bonding units in free TeDs, that result in their low solubility. We propose simultaneous use of donor and acceptor interactions of the TeD ring by forming 4-membered [TeN···MX] secondary bonding units, which include both coordination with a N atom and ChB with the Te atom of the ring (M = metal centre, X = donor atom). Complexes of benzotelluradiazole (BTeD) with AlX3 (X = Cl, Br) were first to demonstrate the viability of such an approach: in various ratios, oligo- or polymeric chains with alternating BTeD and AlX3 units are formed, with the direct N to Al coordination and Te···X distances characteristic for a ChB (2.92–3.22 Å for Cl, 3.02–3.30 Å for Br). Mutual orientation of the fragments is determined by these bonds. Complexation with copper(I) halides (PPh3CuX, X = Cl, Br, I) leads to a series of molecular and polymeric structures, which include Cu–N coordination and Te···X ChBs. Influence of bonding in this series on molecular geometry and spectroscopic properties is discussed.

Библиографическая ссылка: Pushkarevsky N.
Coordination-Supported Chalcogen Bonding for Molecular Design and Enhanced Properties
III Международный симпозиум «Нековалентные взаимодействия в синтезе, катализе и кристаллохимическом дизайне» 19-25 авг. 2024