177565-01-4Relevant academic research and scientific papers
Reactions of Ir(CO)(H)(P(p-tolyl)3)3 with SO2 and O2 Mixtures and with H2SO4, Formation of a Sulfate-Bridged Dimer, and Crystal and Molecular Structure of Ir(CO)(H)(SO2)(P(p-toly
Miller, Cynthia A.,Janik, Thomas S.,Churchill, Melvyn Rowen,Atwood, Jim D.
, p. 3683 - 3686 (1996)
Reactions of HIr(CO)(P(p-tolyl)3)3 with SO2, O2, mixtures of SO2 and O2, and H2SO4 are described. Reactions with mixtures of SO2/O2. and with Hs
Coordination of sulfur dioxide to iridium(I) centers. Sulfur dioxide insertion into a methoxo-metal bond: Crystal and molecular structure of carbonyl(methyl sulfito)(sulfur dioxide)bis(triphenylphosphine)iridium-hemitoluene, the first structurally characterized example of a transition metal complex containing an O-coordinated methyl sulfito ligand
Randall, Sherri L.,Miller, Cynthia A.,Janik, Thomas S.,Churchill, Melvyn Rowen,Atwood, Jim D.
, p. 141 - 147 (2008/10/08)
Reactions of SO2 with iridium(I) complexes have been examined. For trans-Ir(CO)L2X (L = PPh3, P(p-tolyl)3, PCy3; X = Cl, Br, Me), equilibrium constants for SO2 binding have been evaluated. The binding of SO2 is as a Lewis acid and is enhanced by electron-donating groups on the iridium. Increasing the size of the phosphine reduces the equilibrium constant for SO2 binding. Reactions of SO2 with the hydroxo or alkoxo complexes Ir(CO)(OR)L2 (R = H, Me, t-Bu; L = PPh3, P(p-tolyl)3) result in insertion of the SO2 to form an oxygen-coordinated sulfite ligand. The sulfur center of the sulfite ligand is pyramidal and asymmetric, resulting in a second-order 31P NMR spectrum at low temperature. A further rearrangement of the oxygen-coordinated sulfite ligand to the sulfur-coordinated occurs in solution. For R = H, further decomposition of the HSO3- ligand occurs. The products of each reaction are characterized by infrared and 1H and 31P NMR spectroscopy. The product of SO2 insertion into the iridium-methoxo bond, Ir(CO) (OS(O)OMe)(SO2) (PPh3)2, is also characterized by X-ray crystallography. The complex Ir(CO)[OS(O)OMe](SO2)(PPh3)2 crystallizes from toluene as the hemitoluene solvate, Ir(CO)[OS(O)OMe](SO2)(PPh3) 2·0.5(toluene), in the centrosymmetric triclinic space group P1 (No. 2) with a = 10.972(5) A?, b = 11.658(4) A?, c = 18.020(11) A?, α = 82.73(4)°, β = 77.76(4)°, γ = 63.25(3)°, V = 2007.5(17) A?3, and Z = 2. The structure was solved and refined to R = 3.05% and Rw = 3.58% for all 5280 reflections with 2θ w = 3.23% for those 4502 reflections with Fo > 6σ(Fo). The iridium is in a square-pyramidal coordination environment with the SO2 ligand in the apical site. Iridium-ligand bond lengths are as follows: Ir(1)-P(1) = 2.369(2) A? and Ir(1)-P(2) = 2.387(2) A? for the Ir-PPh3 groups, Ir(1)-S(1) = 2.451(2) A? for the SO2 ligand, Ir(1)-C(1) = 1.831(6) A? for the CO ligand, and Ir-O(23) = 2.080(4) A? for the OS(=O)OMe ligand. The trans-basal angles are P(1)-Ir-(1)-P(2) = 170.3(1)° and C(1)-Ir(1)-O(23) = 176.7(2)°; angles to the apical SO2 ligand are P(1)-Ir(1)-S(1) = 97.5(1)°, P(2)-Ir(1)-S(1) = 92.2(1)°, C(1)-Ir(1)-S(1) = 97.3(2)°, and O(23)-Ir(1)-S(1) = 85.8(1)°.
