Synthesis and characterization of copper(ll) complexes of tris(2-benzothiazolylmethyl)amine:A tripodal N₄donor ligand

Abstract

The tetradentate tripodal ligand N,N',N" tris(2-benzothiazolylmethyl)amine has been used to synthesize mononuclear copper(lI) complexes with exogenous ligands X (where X=OAc^-, HCOO^-, N<img src='/image/spc_char/3_bar.gif' border=0>), imidazole, benzimidazole). The X-band EPR spectra, in forzen DMF, indicate the trend of <i>g</i> values which in general is g_ll > g_{<img src='http://www.niscair.res.in/jinfo/line.gif' border=0>} > 2.0. The complex with azide as a exogenous ligand is trigonal bipyramidal in nature. The covalency parameter, ɑ², has been evaluated and reflects the increasing trend of covalency in the order imidazole > benzimidazole > acetate > formate. The <i>E_1/2</i> values for the above complexes have been reported. The present series of complexes possess a distorted five coordinate site, and may have potential relevance to type 3 copper sites in rhus laccase and ascorbate oxidase.