Cationic Iridium(III) Complexes Bearing Phosphaalkene and 2-Pyridylphenyl Ligands

The reactions of [Ir(ppy)2(H2O)2](OTf) (ppy = 2-pyridylphenyl) with 1,2-diaryl-3,4-bis[(2,4,6-tri-tert-butylphenyl)phosphinidene]cyclobutenes (DPCB-Y) afford [Ir(ppy)2(DPCB-Y)](OTf) (Y = CF3 (1), H
(2), and OMe (3)) in high yields. The 2-(2-pyridyl)phosphaethene (P∧N) analogue [Ir(ppy)2(P∧N)](OTf)
(4) is prepared in a similar manner. Complexes 1−4 are characterized by elemental analysis, NMR and
electronic spectroscopy, cyclic voltammetry, and/or X-ray structural analysis.