Electron Spin Resonance Spectral Studies of Some Copper-Oximates

Abstract

Cu(II) chelates of o-hydroxyacetophenoneoxime, resacetophenoneoxime, peonoloxime and 2-hydroxy-1-naphthaldoxime have been prepared. Analysis shewed 1:2 metal to ligand stoichiometry and chelation occurs by the replacement of the hydrogen of the phenolic OH and coordination through the nitrogen of the oxime group. ESR spectral studies have been made on dimethyl formamide solutions of these chelates at room as well as liquid nitrogen temperatures. At low temperature the interaction between the unpaired electron and each copper isotope (Cu⁶³ , Cu⁶⁵) was detected. Cu-2-hydroxy-1-naphthaldoxime chelate showed only a single broad line at room temperature but a well resolved spectrum was observed at LNT. Electronic spectra of the chelates taken in nujol mull and in DMF indicates interaction of the solvent in the axial plane.