Some mono- and dinuclear Hydroxoiridium(I) Complexes

The chloro-bridged iridium(I) compound [Ir-2(mu-Cl)(2)(C8H14)(4)] (1) reacts in the biphasic system benzene/water with KOH in the presence of [NEt3(CH2Ph)]Cl (TEBA) to give the corresponding dinuclear complex [Ir-2(mu-OH)(2)(C8H14)(4)] (2). Stepwise substitution of the cyclooctene ligands by PiPr(3) and ethene affords via the intermediate [Ir-2(mu-OH)(2)(C8H14)(2)(PiPr3)(2)] (isolated as a mixture of isomers 3 a,b) the product [Ir-2(mu-OH)(2)(C2H4)(2)(PiPr(3))(2)] (4) in excellent yield. Reaction of 4 with PiPr(3) in the molar ratio of 1:2 leads to the formation of the mononuclear compound trans-[Ir(OH)(C2H4)(PiPr(3))(2)] (5), the ethene ligand of which cannot be replaced by CPh2 upon treatment with Ph2CN2.