Synthesis and characterization of copper complexes with tripodal ligands bearing amino acid groups

Abstract

The tripodal ligand (2-aminoethyl)bis(2-pyridylmethyl)amine (uns-penp), known for its Cu/O 2 intermediates, was modified at one side arm by a selection of amino acids. With L-Tyrosine (Tyr), L-Histidine (His) and L-Lysine (Lys) it was possible to introduce chirality into the tripodal ligand system and to investigate the corresponding copper(I) complexes [Cu{L-His (BPh 3 )uns-penp}], [Cu(L-Lys)uns-penp]OTf and [Cu(L-Tyr)uns-penp]OTf. [Cu{L-His(BPh 3 )uns-penp}] could be structurally characterized and represents the first example of a copper(I) complex with a coordinated imidazole ring of the histidine ligand. Furthermore, these complexes demonstrated catalytic activity for the oxygenation of thioanisole with hydrogen peroxide as an oxidant.

Synthesis and crystal structure of the copper (II) carboxylate with 2,2-bipyridine, [Cu(4-mba)2(bipy)(H2O)]

“…The Cu(II) ion exists in many enzymes including; such as cytochrome C oxidase [6], dopamine hydroxylase [7], tyrosinate [8], superoxide dismutase [9] and ceruloplasmin [10]. Furthermore, the Cu (II) carboxylate complexes showed different biological activities, such as antibacterial [11], antifungal [12], antiviral [13], and antitumor activities [14].…”