C-H, N-H, and O-H Bond Activations to Prepare Phosphorescent Hydride-Iridium(III)-Phosphine Emitters with Photocatalytic Achievement in C-C Coupling Reactions.

Complex IrH(PPr) () activates two different σ-bonds of 3-phenoxy-1-phenylisoquinoline, 2-(1-benzimidazol-2-yl)-6-phenylpyridine, 2-(1-indol-2-yl)-6-phenylpyridine, 2-(2-hydroxyphenyl)-6-phenylpyridine, -(2-hydroxyphenyl)-'-phenylimidazolylidene, and 1,3-di(2-pyridyl)-4,6-dimethylbenzene to give IrH{κ--[CH-isoqui-O-CH]}(PPr) (), IrH{κ--[NBzim-py-CH]}(PPr) (), IrH{κ--[Ind-py-CH]}(PPr) (), IrH{κ--[CH-py-CHO]}(PPr) (), IrH{κ--[CH-Im-CHO]}(PPr) (), and IrH{κ--[py-CHMe-CHN]}(PPr) (), respectively. The activations are sequential, with the second generally being the slowest. Accordingly, dihydride intermediates IrH{κ--[CH-isoqui-O-CH]}(PPr) (), IrH{κ--[NBzim-py-CH]}(PPr) (), IrH{κ--[Ind-py-CH]}(PPr) (), and IrH{κ--[py-CHMe-py]}(PPr) () were characterized spectroscopically. Complexes and are green phosphorescent emitters upon photoexcitation, exhibiting good absorption over a wide range of wavelengths, emission quantum yields about 0.70 in solution, long enough lifetimes (10-17 μs), and reversible electrochemical behavior. In agreement with these features, complex promotes the photocatalytic α-amino C(sp)-H arylation of ,-dimethylaniline and -phenylpiperidine with 1,4-dicyanobenzene and 4-cyanopyridine under blue LED light irradiation. The C-C coupling products are isolated in high yields with only 2 mol % of photocatalyst after 24 h.