Synthesis, characterization, crystal structure and carbonylation of the perfluorophenoxyiridium(I) complex, trans-(C₆F₅O)Ir(CO)(PPh₃)₂

rans-(C₆F₅O)Ir(CO)(PPh₃)₂ is readily prepared by reaction of NaOC₆F₅ with trans-Ir(CO)(PPh₃)₂Cl. Reaction of trans-(C₆F₅O)Ir(CO)(PPh₃)₂ with CO does not lead to carbonylation of the IrO bond, consistent with expectations of OC₆F₅^-1 loss from the coordination sphere. To further define the bonding of OC₆F₅^-1 to the iridium we have determined the structure. trans-(C₆F₅O)Ir(CO)(PPh₃)₂ crystallizes in the centrosymmetric triclinic space group P1(C_i¹; No. 2) with a 11.901(3), b 12.823(4), c 14.153(5) Å, α 74.223(24), β 88.044(25), γ 66.267(23)°, V 1895.8(10) ų and Z = 3. Diffraction data (Mo-K_α, 2θ 4.5-50.0°) were collected with a Syntex P2₁ automated four-circle diffractometer and the structure was refined to R_F 4.0% for all 6727 independent data (R_F 3.3% for those 5870 data with |F₀| > 6σ (|F₀|)). The d⁸ iridium(I) atom has the expected square-planar coordination geometry with IrP 2.320(1) and 2.321(1) Å, IrCO 1.798(6) Å and IrOC₆F₅ 2.058 (3) Å. Molecular dimensions are very similar to those of trans-PhOIr(CO)(PPh₃)₂ except for the IrOC₆F₅ angle of 135.4(3)°, a value 8.9 ± 0.4° greater than the IrOC₆H₅ angle of 126.5(3)°. This is interpreted as due to increased donation of p-electron density from oxygen to the electronegative C₆F₅ (vis à vis C₆H₅) group.