117477-07-3Relevant academic research and scientific papers
Co-ordination Chemistry of Higher Oxidation States. Part 27. Synthesis, Properties, and Electrochemistry of some cis-Tetrahalogenoiridium(IV) Complexes: Crystal Structure of
Cipriano, Robert A.,Hanton, Lyall R.,Levason, William,Pletcher, Derek,Powell, Nigel A.,Webster, Michael
, p. 2483 - 2490 (1988)
The iridium(IV) complexes cis- have been prepared by Cl2 or HNO3 oxidation of the corresponding IrIII anions -.Dark green cis- (L-L = bipy or phen) and cis- (X = Cl or Br) are also described.Iridium(III) complexes Cl4>- (R = Me or Ph), Cl3>n>, trans-+ , cis-+, and some rhodium(III) analogues, - (L-L = MeSCH2CH2SMe, MeSeCH2CH2SeMe, or bipy) and trans-, are described, but cannot be oxidised to the MnIV state.Complexes have been characterised by i. r., u. v.-visible, n. m. r. (31P, 77Se, and 125Te) spectroscopy, and, for the complex , by X-ray diffraction.Crystals of are monoclinic, space group P21/c with a = 7.410(8), b = 19.256(4), c = 10.477(4) Angstroem, β = 109.39(6) degree, Z = 4, and R = 0.034 for 2 052 reflections.The iridium is six-co-ordinate, Ir-N = 2.042(9), 2.049(9), Ir-Cl = 2.298(3) - 2.311(3) Angstroem.The u. v.-visible spectra of the iridium(IV) complexes are interpreted in terms of ligand-to-metal charge-transfer transitions and compared with the analogous trans-.Electrochemical studies show that for most of the - - couples the electron transfer reaction is close to reversible, with formal potentials for the oxidation occurring at more positive values than for the trans-- - analogues.The rhodium(III) anions show completely irreversible oxidation reactions.
