Electrochemical Synthesis and X-ray Characterisation of Cadmium Complexes Containing 2,6-Bis(1-salicyloylhydrazonoethyl)pyridine − the Influence of the Supporting Electrolyte on the Nature of the Isolated Compounds

Abstract

The influence of the supporting electrolyte and the solvent of crystallisation on the nature of cadmium complexes of 2,6-bis(1-salicyloylhydrazonoethyl)pyridine (H4daps), obtained by an electrochemical procedure, has been investigated. [Cd(H2daps)(H2O)2] (1), [Cd(H2daps)(H2O){(CH3)2CHOH}] (2), [Cd(H3daps)Cl]·CH3CN·0.25H2O (3), [Cd(H3daps)Cl(CH3OH)]·2H2O·CH3OH (4), and [Cd(H2daps)Cl(H2O)]N(CH3)4 (5), have all been isolated and crystallographically characterised. X-ray diffraction studies show that the cadmium atom in 3 is in an unusual pentagonal pyramidal [CdN3O2Cl] geometry, while in the other compounds the cadmium atom is in a bipyramidal pentagonal environment. The organic ligand acts as a pentadentate dianionic ligand in 1, 2, and 5, and as a pentadentate monoanionic ligand in 3 and 4.