Synthesis and Physicochemical Properties of Some β‐Ketoaminato Cobalt(II) Chelates and Their Adducts with 2,2′‐Bipyridine and 1,10‐Phenanthroline

Abstract

The cobalt(II) β‐ketoamines complexes {Co[CH₃C(O)CHC(CH₃)NR]₂; R = CH₃, CH₂(OH)CH₂, C₄H₉} and ketoiminates {Co[CH₃C(O)CH(CH₃)C(‐N(CH₂) _n N‐)C(CH₃)CHC(O)CH₃]} and their adducts with 2,2′‐bipyridine (bipy) and 1,10‐phenanthroline (phen) have been synthesized and characterized by elemental analyses, magnetic susceptibility, conductivity, infrared, and electronic spectral measurements. The ligands coordinate to the cobalt ion in a bidentate manner using the N₂O₂ chromophore. The effective magnetic moments (μ_eff) observed for the complexes are in the range of 4.20–5.30 BM. Electronic spectra results and magnetic susceptibility measurements are consistent with the adoption of a four‐coordinate geometry for the cobalt(II) chelates and a six‐coordinate octahedral geometry for the 2,2′‐bipyridine and 1,10‐phenanthroline adducts. The available conductance data in nitromethane indicates that the compounds are non‐electrolytes.

Acknowledgment

We express our gratitude to the Microanalytical Laboratory, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India for the elemental analyses and the University of Ibadan for a Senate Research Grant. AAO would like to thank the Third World Organisation for Women in Science (TWOWS), Trieste, Italy for a fellowship.