The reaction of [IrCl(CO)(PPh3)2] with LiSeC⋮CR (R = C6H4Me-4) provides [Ir(SeC⋮CR)(CO)(PPh3)2] (1), which undergoes oxidative addition reactions with oxygen, methyl iodide, benzeneselenenyl chloride and bis(4-tolylethynyl)mercury to provide the complexes [Ir(SeC⋮CR)(η2-O2)(CO)(PPh3)2] (2), [Ir(CH3)(SeC⋮CR)I(CO)(PPh3)2] (3), [Ir(CH3)I2(CO)(PPh3)2] (4), [IrCl(SePh)(SeC⋮CR)(CO)(PPh3)2] (5), and [Ir(C⋮CR)(HgC⋮CR)(SeC⋮CR)(CO)(PPh3)2] (6). The complexes 1−3, and 5, and 6 each contain the alkyneselenolate ligand bound to iridium in a monodentate manner through selenium.