Bis(perfluoroaryl)chalcolanes Ar<sup>F</sup><sub>2</sub>Ch (Ch = S, Se, Te) as σ/π-Hole Donors for Supramolecular Applications Based on Noncovalent Bonding
Anton V. Rozhkov, Margarita V. Zhmykhova, Yury V. Torubaev, Eugene A. Katlenok, Dmitry M. Kryukov, Vadim Yu. Kukushkin
Abstract
Perfluorinated arenes (perfluoropyridine, perfluorotoluene, and perfluorobiphenyl) were converted to the bis(perfluoroaryl)chalcolanes Ar F 2 Ch (Ch = S 59–88%, Se 54–84%, Te 10–41%) via the developed one-pot methodology. This method includes the generation of Na 2 Ch (formed in situ by the reduction of Ch with the system Na + [C 10 H 8 ] · – ) followed by its treatment with any one of the arenes. The crystal structures of (4-NC 5 F 4 ) 2 S ( 2 ), (C 12 F 9 ) 2 S ( 3 ) ( p -CF 3 C 6 F 4 ) 2 Se ( 4 ), (C 12 F 9 ) 2 Se ( 6 A,B; two polymorphs), (C 12 F 9 ) 2 Te ( 9 ), and (4-NC 5 F 4 ) 2 Te ( 8 B; a novel polymorph) were determined by X-ray crystallography. In the solid state, compounds Ar F 2 Ch are self-associated via σ-(Ch)-hole interactions with F (or N for 8 B ) and also π–π stacking between the arenes. The σ/π-hole donor properties of Ar F 2 Ch were evaluated by molecular electrostatic potential surface analysis using the density functional theory approach. The maximum V s (σ-hole) values (from +25 to +38 kcal/mol) increase in the order S < Se < Te along with an increase in the polarizability and decrease in the electronegativity of the Ch sites, while the π-hole depths (+14 to +20 kcal/mol) follow the opposite trend being the lowest for the Te II derivatives.