Synthesis and Characterization of a New Quinquedentate Ligand Consisting of Salen Skeleton and Phenolic Tail Capable of Axial Coordination and Its Metal Complexes

Abstract

Abstract A New quinquedentate ligand N,N′-disalicylidene-2-methyl-4-(2-hydroxy-5-methylphenyl)-1,2-butanediamine (H2(sal-Hpen)) has been prepared, which is a salen derivative containing a phenolic tail capable of axial coordination. It formed the complexes of a general formula [M(sal-Hpen)] with copper(II), nickel(II), and cobalt(II) ions. Based on infrared, electronic and ESR spectra, the complexes were revealed to assume a planar coordination, free from axial coordination of the phenolic tail. On the other hand, distorted octahedral cobalt(III) and tetragonal pyramidal iron(III) complexes, [Co(sal-pen)py] and [Fe(sal-pen)], were obtained, where sal-pen3− acts as a quinquedentate ligand.