Synthesis and characterization of heterodinuclear RuPt and IrPt complexes containing pyrazolate bridging ligands. Crystal structure of [(η5-C5Me5)Ir(μ-pz)3PtMe3] (pz=pyrazolate)

Abstract The reaction of the metallo–ligand [Ru(η 6 - p -cymene)(pz) 2 (Hpz)] with the platinum complex [{PtIMe 3 } 4 ] affords mixtures of the heterodinuclear complexes [(η 6 - p -cymene)Ru(μ-pz) 3 PtMe 3 ] ( 1 ) and [(η 6 - p -cymene)Ru(μ-pz) 2 (μ-I)PtMe 3 ] ( 2 ). The reaction of the iridium derivative [Ir(η 5 -C 5 Me 5 )(pz) 2 (Hpz)] with [{PtIMe 3 } 4 ] gives [(η 5 -C 5 Me 5 )Ir(μ-pz) 2 (μ-I)PtMe 3 ] ( 3 ). Both [Ru(η 6 - p -cymene)(pz) 2 (Hpz)] and [Ir(η 5 -C 5 Me 5 )(pz) 2 (Hpz)] react with [{PtIMe 3 } 4 ] in the presence of NaOH yielding 1 and [(η 5 -C 5 Me 5 )Ir(μ-pz) 3 PtMe 3 ] ( 4 ), respectively. While [Ru(η 6 - p -cymene)(pz) 2 (Hpz)] reacts with [PtBr 2 Me 2 S x ] to give mixtures of [(η 6 - p -cymene)Ru(μ-pz) 3 PtBrMe 2 ] ( 5 ) and [(η 6 - p -cymene)Ru(μ-pz) 2 (μ-Br)PtBrMe 2 ] ( 6 ), the reaction of [Ir(η 5 -C 5 Me 5 )(pz) 2 (Hpz)] with [PtBr 2 Me 2 S x ] gives [(η 5 -C 5 Me 5 )Ir(μ-pz) 2 (μ-Br)PtBrMe 2 ] ( 7 ) as the sole product. All species were characterized in solution by 1 H-NMR spectroscopy. The crystal structure of complex 4 has been determined by single-crystal X-ray diffraction.