Synthesis and coordination behaviour of hydroxamate resin with varying spacer groups

Abstract

Three kinds of chelating resin-containing hydroxamic acid functional groups with varying spacer groups were synthesized. They are acetohydroxamate resin (P-3), glycinohydroxamate resin (P-9) and γ-aminobutyrohydroxamate resin (P-13). The coordination behaviour of copper(II) ions for these resins was studied with the aid of EPR, IR, electronic spectra and potentiometry. The EPR studies show that the formation of metal-resin complexes is pH-dependent. The g value and A values, calculated from the spectral data, indicate that the copper(II) environment could be of oxygen atoms only, as CuO 4 species. The electronic spectra along with EPR spectra suggest a square planar environment around the copper(II) in these resin complexes. The bidentate character of the synthesized resin was also inferred from IR spectra. The results derived from EPR, electronic spectra and potentiometry show that P-3 favours intermolecular complexation, and P-9 or P-13 favours intramolecular complexation predominantly.