The SN2 reaction and its relationship with the Walden inversion, the Finkelstein and Menshutkin reactions together with theoretical calculations for the Finkelstein reaction

Abstract

This communication gives an overview of the relationships between four reactions that although related were not always perceived as such: SN2, Walden, Finkelstein, and Menshutkin. Binary interactions (SN2 & Walden, SN2 & Menshutkin, SN2 & Finkelstein, Walden & Menshutkin, Walden & Finkelstein, Menshutkin & Finkelstein) were reported. Carbon, silicon, nitrogen, and phosphorus as central atoms and fluorides, chlorides, bromides, and iodides as lateral atoms were considered. Theoretical calculations provide Gibbs free energies that were analyzed with linear models to obtain the halide contributions. The M06-2x DFT computational method and the 6-311++G(d,p) basis set have been used for all atoms except for iodine where the effective core potential def2-TZVP basis set was used. Concerning the central atom pairs, carbon/silicon vs. nitrogen/phosphorus, we reported here for the first time that the effect of valence expansion was known for Si but not for P. Concerning the lateral halogen atoms, some empirical models including the interaction between F and I as entering and leaving groups explain the Gibbs free energies.

Understanding the Reaction Kinetics and Microdynamics between Methylimidazole and Alkyl Thiocyanate for Ionic Liquid Synthesis through Experiments and Theoretical Calculation

“…ILs are commonly synthesized by two neutral reactants to form oppositely charged ions, which belong to the Menshutkin S N 2 reaction. − There are several reports on the reaction kinetics of the synthesis of ILs. For example, Schleicher et al studied the preparation of 1-hexyl-3-methylimidazoline bromide in 10 different solvents with emphasis on the solvent effects on the reaction kinetics .…”