Ternary Coordination Complexes Formed by Copper(II) with Thio-or Dithiodialkanoic Acids and Some Selected Ethyl-substituted Malonic Acids

Abstract

Abstract Binary and ternary complexes formed by copper(II) with thio- or dithiodialkanoic acids and ethyl-substituted malonic acids have been investigated potentiometrically in an aqueous solution and the relevant stability constants have been evaluated using computer technique. Thio- and dithiodialkanoic acids were thiodiacetic, dithiodiacetic, 3,3′-thiodipropionic, and 3,3′-dithiodipropionic acids. The results are discussed in terms of substituent influences upon the chelation of the malonate dianions to the systems copper(II)-thiodialkanoic acids. It is suggested that in the mixed copper chelates containing thiodiacetic acid, the geometrical characteristics of the more basic ligand, governs the coordination of the other ligand.