(η 5 ‐Pentamethylcyclopentadienyl)iridium( III ) Complexes with η 2 ‐N,O andη 2 ‐P,S Ligands

Chloro(η 5 ‐pentamethylcyclopentadienyl)(η 2 ‐pyridine‐2‐car‐boxylato)iridium( III ) [Ir(η 5 ‐C 5 Me 5 )(η 2 ‐C 5 H 4 N‐2‐CO 2 )Cl] ( 2 ) and chloro(η 5 ‐pentamethylcyclopentadienyl)[η 2 ‐2‐(diphenylphosphanyl)thiophenolato]iridium( III ) [Ir(η 5 ‐C 5 Me 5 )(η 2 ‐2‐Ph 2 PC 6 H 4 S)Cl] ( 3 ) were prepared and their structures determined by single‐crystal X‐ray diffraction analysis. Complex 2 crystallizes in the orthorhombic space group Pbca . The number of molecules per unit cell is eight, whereas 3 crystallizes in the orthorhombic space group Pna 2 1 and the number of molecules per unit cell is four. The coordination of the η 2 ‐bound ligands in 2 and 3 leads to chelate bite angles N–Ir–O(2) and P–Ir–S of 77.0(2)° and 82.42(7)°, respectively. The iridium atoms in 2 and 3 are chiral and both enantiomers are present in the unit cell. The substitution of the chloro ligand in 3 affords hydrido(η 5 ‐pentamethylcyclopentadi‐enyl)‐[η 2 ‐2‐(diphenylphosphanyl)thiophenolato]iridium( III ][Ir(η 5 C 5 Me 5 )(η 2 ‐2‐Ph 2 PC 6 H 4 S)H] ( 4 ) and methyl(η 5 ‐penta‐methylcyclopentadienyl)[η 2 ‐2‐(diphenylphosphanyl)thiophen‐olato]iridium( III ) [Ir(η 5 ‐C 5 Me 5 )(η 2 ‐2‐Ph 2 PC 6 H 4 S)Me] ( 5 ), respectively, in good yields. The 31 P{ 1 H} NMR resonances of 4 ( δ = 33.9 ppm) and 5 ( δ = 35.8 ppm) prove unambiguously that the 2‐(diphenylphosphanyl)thiophenolato ligand still remains η 2 ‐coordinated.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)