Synthesis and characterisation of copper(II), cobalt(II), nickel(II), iron(II) and oxovanadium(IV) chelates of a new pair of Schiff base ligands derived from 1, 3-bis( aminomethyl)cyclohexane

Abstract

A few complexes of Cu(II), Co(II), Ni(II), Fe(ll) and oxovanadium (IV)ions of a pair of Schiff base ligands, BAMC-Sal and BAMC-Pyrog, derived from 1, 3-bis(aminomethyl)cyclohexane and either salicylaldehyde or pyrogallaldehyde have been. synthesised and characterised by elemental analysis, spectral and magnetic studies. The studies indicate that copper(II) complexes stack as dimers in solid state with a square-pyramidal geometry around the metal centres which upon dissolution monomerise to give pseudo-tetrahedral geometry. The cobalt(II) halides give a trinuclear (CoL)₂CoX₂ structure with mixed spin states where LH₂ is the ligand and X a non-bridging halide ligand on the central cobalt(II) ion. Other cobalt(II) salts, besides, nickel(II), iron(II) and oxovanadium(IV) ions give monomeric ML type complexes with octahedral for Co(II), tetrahedral for Ni(II) and Fe(II) and square-pyramidal geometries for VO(II) metal ions.