187035-77-4Relevant academic research and scientific papers
Solvent Dependence of the Reaction of η5-C5 Me5Ir(Co)2 with Aryldiazonium Ions. Synthesis and Characterization of Mono- and Diiridium Carbonyl Complexes Including the X-ray Structures of [{η5-C5Me5Ir(Co)} 2(1-η 1-1,2-η2-p-C6H 4OMe)]BF4
Yan, Xiaoqian,Batchelor, Ramond J.,Einstein, Frederick W.B.,Zhang, Xiaoheng,Nagelkerke, Ruby,Sutton, Derek
, p. 1237 - 1246 (1997)
Reaction of Cp*Ir(CO)2 (3, CP* = η5-C5Me5) with [N2Ar][BF4] (Ar = p-C6H4OMe) in acetone at -78°C affords the nitrogen extrusion product [Cp*Ir(CO)2(Ar)][BF4] (5), but in dichloromethane it yields a dinuclear product [Cp*(CO)2Ir-Ir(Cl)(CO)Cp*][BF4] (6). By carrying out this very reaction in ethanol solution, a nitrogen-retained product [Cp*Ir(CO)(OEt)(NHNAr)][BF4] (7) is obtained, containing an aryldiazene ligand. Deprotonation of 7 gives quantitatively the neutral doubly-bent aryldiazenido complex Cp*Ir(CO)(OEt)(N2Ar) (8). The IR v(CO) absorptions measured for the dinuclear compound 6 indicate no bridging carbonly, but a 13C NMR study in solution shows that 6 is stereochemically nonrigid at ambient temperature; its three carbonyl ligands are all involved in a fast exchange process, and this process is frozen at -86 °C. Exchange of the CO groups via a terminalbridging- terminal process accompained by rotation about the Ir-Ir axis is suggested. The molecular structure of 6 in the solid state has been established by single crystal X-ray crystallographic analysis and is consistent with the solution spectra. By reaction of [N2Ar][BF4] with the dinuclear complex [Cp*Ir(CO)]2 (4) in acetone, the complex [{Cp*Ir(CO)}2(1-η1-1,2-η 2-p-C6H4OMe)][BF4] (9) with a rare σ,π-bridging aryl group has been obtained and crystallyzed. The molecular structure containing an asymmetric bridging aryl group is established for 9 in the solid state by a single crystal X-ray crystallogaphic analysis. However, the identical 1H NMR features observed at ambient temperuture and -90 °C in solutin (i.e., a singlet resonance for the two Cp* ligands and a symmetric AA'BB' pattern for the p-C6H4OMe) indicate a static or time-averaged symmetrical molecular geometry for 9. Compound 6 crystallizes in the monoclinic space group P21/c with a = 10.583(2) A?, b = 14.256(3) A?, c =16.818(4) A?, β = 95.91 (2)°, V = 2523.9 A?3, and Z = 4. Refinement yielded RF = 0.033 for 3299 observed reflection (Io ≥ 2.5σ(Io)) of 4427 unique reflections. Compound 9 crystallizes in the monoclinic space group P21/n with a = 11.695(2) A?, b = 19.911(3) A?, c = 12.539(2) A?, β = 96.54(1)°, V = 2900,8 A?3, and Z = 4, Refinement yielded RF = 0.025 and RWF = 0.035 for 3444 observed reflections (Io ≥ 2.5σ(Io) of 4526 unique reflections.
