ja512183e_si_001.pdf (4.66 MB)
Chalcogen Bonding in Solution: Interactions of Benzotelluradiazoles with Anionic and Uncharged Lewis Bases
journal contribution
posted on 2015-04-01, 00:00 authored by Graham
E. Garrett, Gregory L. Gibson, Rita N. Straus, Dwight S. Seferos, Mark S. TaylorChalcogen
bonding is the noncovalent interaction between an electron-deficient,
covalently bonded chalcogen (Te, Se, S) and a Lewis base. Although
substantial evidence supports the existence of chalcogen bonding in
the solid state, quantitative data regarding the strengths of the
interactions in the solution phase are lacking. Herein, determinations
of the association constants of benzotelluradiazoles with a variety
of Lewis bases (Cl–, Br–, I–, NO3– and quinuclidine,
in organic solvent) are described. The participation of the benzotelluradiazoles
in chalcogen bonding interactions was probed by UV–vis, 1H and 19F NMR spectroscopy as well as nano-ESI
mass spectrometry. Trends in the free energy of chalcogen bonds upon
variation of the donor, acceptor and solvent are evident from these
data, including a linear free energy relationship between chalcogen
bond donor ability and calculated electrostatic potential at the tellurium
center. Calculations using the dispersion-corrected B97-D3 functional
were found to give good agreement with the experimental free energies
of chalcogen bonding.