94118-47-5Relevant academic research and scientific papers
Iridium(III) Complex Containing a Unique Bifurcated Hydrogen Bond Interaction Involving Ir-H?H(N)?F-B atoms. Crystal and Molecular Structure of [IrH(η1-SC5H4NH)(η2-SC 5H4N)(PPh3)2](BF 4)·0.5C6H6
Park, Sunghan,Lough, Alan J.,Morris, Robert H.
, p. 3001 - 3006 (1996)
A synthetic route to a new iridium(III) complex containing a novel proton hydride bonding interaction has been established. fac-IrH3(PPh3)3 reacts with 2-mercaptopyridine HSpy (Spy = 2-SC5H4N) to give the known dihydride Ir(H)2(η2-Spy)(PPh3)2 8. Ir(H)2(η2-Spy)(PPh3)2 reacts with HSpy· HBF4 to give [IrH(η1-SC5H4NH)(η2-SC 5H4N)-(PPh3)2](BF4) 9 which possesses a unique bifurcated hydrogen bonding interaction involving Ir-H?H(N)?F-B atoms with the distances of 2.0(1) A? for the H?H unit and of 2.0(1) A? for the F?H unit in the crystalline state. In solution the N-H?H-Ir interaction is maintained according to 1H T1(min) and nOe measurements. Isotope shifts in the chemical shifts of the hydride and one phosphorus of 9 have been observed in 1H and 31P{1H} NMR spectra of [IrH(η1-SC5H4ND)(η2-SC 5H4N)(PPh3)2](BF4), 9-d1, prepared by the reaction of 9 with MeOD or CF3-CO2D. The crystal and molecular structure of [IrH(η1-SC5H4NH)(η2-SC 5H4N)(PPh3)2](BF 4)·0.5C6H6 9 has been solved by X-ray analysis: monoclinic space group P21/c with a = 17.723(3) A?, b = 10.408(1) A?, c = 26.073(4) A?, β= 108.08(1)°, V = 4572.0(11) A?3, and Z = 4. The known complex fac-IrH3(PPh3)3, 7, is made by a new and improved method by reacting mer-IrHCl2(PPh3)3 with NaOEt and H2(g). VT-1H NMR spectra (+90 to -80 °C) of the hydrides of 7 reveal that the JAA and JAX couplings change in the AA'A''XX'X'' pattern (A = 1H, X = 31P) but that the complex is not fluxional. The T1(min) value of 0.144 s for the hydrides of 7 at -60 °C (300 MHz) indicates that the shortest H-H distances are about 1.8 A?.
