Menschutkin reactions of aliphatic diamines with methyl iodide in acetonitrile–methanol mixtures. Evaluation of the role of the non-reacting nitrogen atom

Abstract

Kinetic and thermodynamic analyses have been performed for the reactions of aliphatic diamines with methyl iodide in acetonitrile–methanol mixtures. Solvation patterns around non-reacting nitrogen atoms have been evaluated for activated complexes and for product cations. These analyses enable the two transition-state indices due to physical interaction, i.e. extended Brønsted coefficients, α_PHYS and isokinetic temperatures, β_PHYS to be determined. An empirical correlation between β_PHYS and α_PHYS multiplied by the dipole moment of an initial state, has been found, and the physical significance of the correlation is discussed. Multiple use of transition-state indices and their empirical analyses are indispensable for characterizing the particular roles played by non-reacting nitrogen atoms in these reactions.