Hydrogen Bond and Other Lewis Acid-Lewis Base Interactions as Preliminary Stages of Chemical Reactions.

Sławomir J Grabowski

doi:10.3390/molecules25204668

Abstract

Various Lewis acid–Lewis base interactions are discussed as initiating chemical reactions and processes. For example, the hydrogen bond is often a preliminary stage of the proton transfer process or the tetrel and pnicogen bonds lead sometimes to the SN2 reactions. There are numerous characteristics of interactions being first stages of reactions; one can observe a meaningful electron charge transfer from the Lewis base unit to the Lewis acid; such interactions possess at least partly covalent character, one can mention other features. The results of different methods and approaches that are applied in numerous studies to describe the character of interactions are presented here. These are, for example, the results of the Quantum Theory of Atoms in Molecules, of the decomposition of the energy of interaction or of the structure-correlation method.

Highlights

It is well known that the hydrogen bond plays a crucial role in numerous chemical, physical and biological processes [1,2]
This is why the aim of this review is to point out relationships between interactions and reactions since the former phenomena may lead to the latter ones they initiate numerous structural changes and electron charge redistributions in species being in contact. This is of particular interest, which characteristics possess interactions that lead to chemical reactions. It was discussed in one of recent reviews that the stronger electrostatic interactions lead to the stronger Pauli repulsion that implies the greater electron charge shifts, mainly from the Lewis base unit to the Lewis acid; these phenomena may lead to the chemical reaction [11]
Different interactions are discussed in this article; the hydrogen bond and its special type—the dihydrogen bond, the pnicogen, and tetrel bonds as representatives of the σ-hole bond, and the triel bond as an example of the π-hole bond

Summary

Introduction

It is well known that the hydrogen bond plays a crucial role in numerous chemical, physical and biological processes [1,2]. Knowledge of the potential surface, characterizing the mutual trajectories of the reactants, is necessary to obtain the rates of chemical reactions” [10] This is why the aim of this review is to point out relationships between interactions and reactions since the former phenomena may lead to the latter ones they initiate numerous structural changes and electron charge redistributions in species being in contact. This is of particular interest, which characteristics possess interactions that lead to chemical reactions It was discussed in one of recent reviews that the stronger electrostatic interactions lead to the stronger Pauli repulsion that implies the greater electron charge shifts, mainly from the Lewis base unit to the Lewis acid; these phenomena may lead to the chemical reaction [11]. Few types of interactions are discussed and it is analysed which conditions should be fulfilled for them that they lead to chemical reactions

The Hydrogen Bond as a Preliminary Stage of the Proton Transfer Process

The Case of Halogen Bonds

The Dihydrogen Bond as a Stage of the Molecular Hydrogen Uptake

Tetrel Bonds and the SN 2 Reaction

Summary