Kinetic Features of the Base Hydrolysis of Schiff Base Complexes

This work deals with the preparation, characterization and kinetic studies on base hydrolysis of some Fe(II) Schiff base amino acid complexes.The prepared complexes were found to be of 1:2 or 1:1 stoichiometry and non – electrolytic character, solubility measurements of these complexes showed them as hydrophobic in nature. The base hydrolysis reaction of the prepared complexes was carried out in aqueous, co-organic media and in the presence of added salts. The kinetic measurements confirmed the pseudo 1st – order rate dependence in [complex] and 2nd – order in [OH-]. A relevant mechanism was suggested in which the parallel attack of OH- ion on the central Fe(II) atom and the dissociation of the first ligand is provided as rate – determining step. The observed decrease of base hydrolysis rate constant kobs. with increasing the mole fraction of co-organic solvent indicates solute – solvent interaction between delocalized charge in complex and dispersion centers on solvent molecules.