A trans influence study in propyl (aquo)cobaloxime by imidazoles and amino acids

Substitution reactions of propyl cobaloxime with imidazole, substituted imidazoles, histidine, histamine, glycine and ethyl glycine ester are carried out as a function of pH. Trends in the formation constants are explained based on the steric hindrance, extent of p-bonding and s-donor capacity of the incoming ligand. Molecular mechanics is used to theoretically determine the bond length and bond strain values by MM2 parametrization and these are correlated with the experimental data.