Electroactive poly zinc, cadmium, manganese ferrocenylphenylphosphinates

The synthesis of ferrocenylphenylphosphinic acid in high yield is reported. The electrochemical behaviour of ethyl ferrocenylphenylphosphinate, ferrocenylphenylphosphinic acid and its sodium salt are compared. The preparation and characterization of zinc, cadmium and manganese ferrocenylphenylphosphinates are reported. They are anhydrous and show a high thermal stability. The iso-structurality of these compounds is settled, and a structure involving double bridging phosphinate groups is proposed. Their half wave potentials, determined by cyclic voltammetry using a cavity micro electrode are similar to each other, and are close to that of the sodium salt of ferrocenylphenylphosphinic acid, and even to those of the related metal ferrocenylphosphonates M(II)(HO3PFc)2 · xH2O.