Trimeric Iridium(I) and Iridium(III) Complexes with the Tripodal Phosphane cis, cis-1,3,5-Tris[(diphenylphosphanyl)methyl]cyclohexane (tdppmcy) as Bridging Ligand


  • Dedicated to Professor Reinhard Schmutzler on the occasion of his 60th birthday.


Treatment of cis,cis-1,3,5-tris[(diphenylphosphanyl)methyl]-cyclohexane (tdppmcy) (1) with Ir(PPh3)2(CO)Cl in toluene gives the trinuclear complex [Ir(CO)Cl]3(tdppmcy)2 (2) in high yield. In this complex the tripodal molecule tdppmcy behaves as a trismonodentate ligand since each phosphorus atom is bound to one metal center. Compound 2 can be transformed into the trinuclear complexes {[Ir(CO)-(Cl)H]3(tdppmcy)2)3+ (3), [Ir(CO)(Cl)H2]3(tdppmcy)2 (4), and [Ir(CO)H3]3(tdppmcy)2 (5) by treatment with H+, H2, and H, respectively. The chemistry of 2 supports the spectroscopic findings of a square-planar environment at the metal centers in 2.