Date of Award
Master of Arts
Dr. Dean W. Cooke
Dr. Joseph Kanamueller
Dr. Ralph Steinhaus
Masters Thesis-Open Access
Aminocarboxylic acid cobalt(III) complexes have been of interest to inorganic chemists since 1909 when Ley and Winkler isolated violet and rose colored geometric isomers of tris amino acid complexes of glycine and alanine.1 More recently, considerable interest has been shown in the study of the stereochemistry and optical activity arising from configurational and vicinal interactions of these complexes. Nuclear magnetic resonance of the methylene protons on the carboxylate portion of the coordinated ligand has also been studied.
Of immediate interest to this study is the stereo-chemistry of complexes containing flexible tetradentate ligands. A tetradentate ligand may be constructed such that the four coordination sites are arranged in a linear manner or in a branched or non-linear manner. In recent years, because of the variety of linear tetradentate Ligands which are easily obtainable or readily synthesized, stereochemical studies of complexes containing these ligands have been considerably investigated while the non-linear ligands have not been extensively studied. Various donor atoms such as nitrogen, oxygen, sulphur, and phosphorous have been utilized. In addition, the lengths of the connecting alkyl chains have been varied and methyl substituants have been placed at various sites along the tetradentate chain. The effect of these changes on the stereochemistry of the resulting complexes has been observed. An octahedral complex with a linear tetradentate ligand may assume three distinct geometrical arrangements as shown in Figure 1. (For simplicity, only the coordinated atoms are shown).
Magnell, Paul John, "Cobalt(III) Complexes With 1,2-Propanediaminediacetic Acid" (1970). Masters Theses. 4372.