Coordination complexes of amino acids: Preparation and properties of some copper(II) and copper(I) complexes containing mixed bidentate ligands

Abstract

Complexes of copper(II) of the type [CuAB] have been synthesized in which A is the anion of acetylacetone, salicylaldehyde, 8- hydroxyquinoline, or diethyl-dithiocarbamate, and B is the anion of phenylalanine, tryptophan, or tyrosine. Examination of their spectral, magnetic, and solubility behaviour established them to be normal, molecular, copper(II) complexes. Bis(2,9-dimethylphenanthroline)copper(I) amino-acidates were also prepared. Their spectra suggest that, in solution at least, no coordination of the amino acid to the copper(I) occurs. Preliminary irradiation experiments, at 3080 Ǻ, show that photo- reduction to copper(I) occurs in dimethylformamide solutions; the copper(I) complexes remained unchanged under the same conditions.