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Title: Ability of Lewis Acids with Shallow σ-Holes to Engage in Chalcogen Bonds in Different Environments
Molecules of the type XYT = Ch (T = C, Si, Ge; Ch = S, Se; X,Y = H, CH3, Cl, Br, I) contain a σ-hole along the T = Ch bond extension. This hole can engage with the N lone pair of NCH and NCCH3 so as to form a chalcogen bond. In the case of T = C, these bonds are rather weak, less than 3 kcal/mol, and are slightly weakened in acetone or water. They owe their stability to attractive electrostatic energy, supplemented by dispersion, and a much smaller polarization term. Immersion in solvent reverses the electrostatic interaction to repulsive, while amplifying the polarization energy. The σ-holes are smaller for T = Si and Ge, even negative in many cases. These Lewis acids can nonetheless engage in a weak chalcogen bond. This bond owes its stability to dispersion in the gas phase, but it is polarization that dominates in solution.  more » « less
Award ID(s):
1954310
NSF-PAR ID:
10326170
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Molecules
Volume:
26
Issue:
21
ISSN:
1420-3049
Page Range / eLocation ID:
6394
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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