Stereodynamics and reactions of degenerated ligand exchange in cadmium-111 bis-(N-alkyl-β-aryl-β-thiovinylaldiminate) solutions

Kinetics of intramolecular enanthiomerization and degenerated ligand exchange in series of intracomplex 111Cd compounds has been studied by the dynamic NMR method. Analysing temperature-dependent spectra, one makes the conclusion about the presence of two types of processes: low-temperature (LT) process of intramolecular enanthiomerization (the kinetic order of the reaction equals 1) and high-temperature (HT) process of degenerated ligand exchage (the reaction order equals 2). The conclusion that the LT process running according to the mechanism of a diagonal twist is low barrier in comparison with HT process of ligand exchange. Variation of substitutes in the ligand structure in Br, NO2, OCH3 series influences insignificantly on kinetics of enanthiomerization and ligand exchange