Abstract
Empirical substituent constants such as the Hammett parameters have found important utility in organic and other areas of chemistry. They are useful both in predicting the impact of substitutions on chemical processes and in rationalizing, after the fact, observations on chemical bonding and reactivity. We assess the impact of substitutions on mono-iodinated benzene rings and find that the modifications that substituents induce on the electrostatic potentials at the sigma hole on the terminal I center correlate strongly with established trends of common substituents. As an alternative to the experimental procedures involved in obtaining empirically based substituent constants, the computationally determined constants based on induced electrostatic potentials offer a model for quantifying the influence of mono- and polyatomic, neutral and ionic, substituents on their compounds. A partitioning scheme is proposed that allows us to discretely separate σ and π contributions to generate quantitative measures of substituent effects.
Document Type
Article
Publication Date
11-20-2023
Publisher Statement
Copyright © 2023 The Authors. Published by American Chemical Society
Recommended Citation
Donald, K. J., Pham, N., & Ravichandran, P. (2023). Sigma hole potentials as tools: Quantifying and partitioning substituent effects. The Journal of Physical Chemistry A, 127(48). https://pubs.acs.org/doi/10.1021/acs.jpca.3c05797