Synthesis,Characterization and Magnetic Properties of New Dinuclear Copper(II) Complexes with N,N′‐Disubstituted Dithiooxamides derived from α‐Amino Acids

Four new dinuclear copper(II) complexes have been synthesized and have the general formula Cu₂(L)(H₂O)₂], where L = GLYDTO N,N′‐bis(carboxymethyl)dithiooxamide], ALADTO N,N′‐bis(carboxyethyl)dithiooxamide], VALDTO N,N′‐bis(1‐carboxy‐2‐methylpropyl)dithiooxamide] and LEUDTO N,N′‐bis(1‐carboxy‐3‐methylbutyl)dithiooxamide]. The complexes were characterized by elemental analysis as well as by IR, electronic and EPR spectroscopy. These techniques provided evidence for the presence of the CuNO₂S chromophore. Magnetic susceptibility measurements on all the complexes in the range 4–300 K show the existence of a dominant antiferromagnetic interaction with ?J values greater than 300 cm^?1. Thermal decomposition behaviour of the complexes was studied by thermogravimetry.