The Use of Hammett Constants to Understand the Non-Covalent Binding of Aromatics

Abstract

Non-covalent interactions of aromatics are important in a wide range of chemical and biological applications. The past two decades have seen numerous reports of arene-arene binding being understood in terms Hammett substituent constants, and similar analyses have recently been extended to cation-arene and anion-arene binding. It is not immediately clear why electrostatic Hammett parameters should work so well in predicting the binding for all three interactions, given that different intermolecular forces dominate each interaction. This review explores such anomalies, and summarizes how Hammett substituent constants have been employed to understand the non-covalent binding in arene-arene, cation-arene and anion-arene interactions.

Investigation of Electrostatic Interactions towards Controlling Silylation‐Based Kinetic Resolutions

“…A linear free energy relationship (LFER) was found for the four substrates when sigma meta ( σ m ) substituent parameters were plotted against the log of the selectivity factor showing that as electron‐withdrawing groups become stronger selectivity increased, resulting in a significant sensitivity constant ( ρ ) of 2.6 (Figure ). Methoxy is an electron‐withdrawing group when employing sigma meta, which is consistent with the increase in selectivity over just phenyl.…”

2-Amino-3′-dialkylaminobiphenyl-based fluorescent intracellular probes for nitric oxide surrogate N2O3

“…Subsequently, we set X as NMe 2 and changed the weakly donating methyl (s + ¼ À0.311) at Y to a strongly-withdrawing cyano group, (s + ¼ 0.659). 98 With no cinnoline uorescence detected, we concluded that the nitrile group inhibits the nucleophilicity of the p-amine to such an extent that it could not N-nitrosate.…”

Binding Constants of Substituted Benzoic Acids with Bovine Serum Albumin

“…The Hammett constants describe the electron donating or withdrawing ability of a substituent in comparison with a hydrogen atom. Equilibrium and rate constants of various chemical processes involving substituted benzoic acids derivatives and other aromatic compounds have been shown to correlate with these constants [26,27]. The applications of this approach to protein-ligand binding are quite limited.…”