777855-63-7Relevant academic research and scientific papers
Isolation and characterization of iridium(III) and iridium(V) complexes of 2-(arylazo)pyridine and studies of amine fusion reactions at the coordinated diazo-ligand
Panda, Manashi,Das, Chayan,Lee, Gene-Hsiang,Peng, Shie-Ming,Goswami, Sreebrata
, p. 2655 - 2661 (2007/10/03)
The reaction of IrCl3·3H2O with 2-(arylazo)pyridine (HL1) in boiling methancil has afforded [Ir IIICl2(L1)(HL1)] (1) and [Ir VCl4(HL1)]Cl (2). In complex 1, one of the two ligands [L1]- is orthometallated via coordination of an ortho-carbon of the aryl ring of [L1]- and one of the two azo nitrogens to form a five-membered chelate X-Ray crystal structures of the two representative complexes, viz. 1a and 2a, have been solved. Notably, the Ir-N length (2.140(3) A) trans to the Ir-C bond in la is appreciably longer than the other three Ir-N lengths present in the same molecule. The N-N lengths in these two compounds lie close to that observed in the uncoordinated ligand. Thorough NMR studies were made to authenticate the carbon-bonded structure of compound la. In its 13C NMR spectrum, the resonance near δ 148 is assigned to the carbon bonded to the iridium metal center. UV-visible spectra along with the redox properties of these complexes are reported. The iridium(v) complex, 2 showed a reversible response near 1.40 V, presumably due to the iridium(v)-iridium(vi) couple. Several reductive responses at cathodic potentials, due to ligand reductions, were also observed. Metal promoted aromatic ring amination reactions at the coordinated HL1 ligand in complexes 1 and 2 were investigated. The products were characterized using X-ray diffraction.
