Cobalt-assisted condensation of 2-butanone oxime and acetone: Synthesis and X-ray structure of the novel acetaldiimine complex [CoI2{((CH3CH2)(CH3)C=NO)(2)C(CH3)(2)}]

The synthesis of the first acetaldiimine cobalt complex and its full charac terisation are reported. The nitrogen-bonded chelate complex [CoI2{((CH3CH2 ) (CH3)C=NO)(2)C(CH3)(2)}] is obtained in high yield from the reaction of 2 -butanone oxime with cobalt iodide dihydrate in acetone, in the presence of trimethyl orthoformate as dehydrating agent. A single-crystal X-ray struct ure determination, infrared spectroscopy and mass spectrometry analyses con firm the formation of a new ligand in situ from the addition of an acetone molecule to two oximato species. This cobalt-mediated reaction provides an indirect proof for the existence in solution of monodentate N-bonded cobalt -ketoxime species.