Synthesis and structural characterization of two novel heterometallic clusters: [Rh4Pt2(CO)11(dppm)2] and [Ru2Rh2Pt2(CO)12(dppm)2]

Abstract

Two novel heterometallic octahedral clusters [Rh₄Pt₂(CO)₁₁(dppm)₂] (1) and [Ru₂Rh₂Pt₂(CO)₁₂(dppm)₂] (2) were synthesized by the reaction of [Rh₂Pt₂(CO)₆(dppm)₂] with [Rh₆(CO)₁₄(NCMe)₂] and Ru₃(CO)₁₂, respectively. Solid state structures of 1 and 2 have been established by a single crystal X-ray diffraction study. Two dppm ligands in 1 are bonded to one platinum and three rhodium atoms, which form an equatorial plane of the Rh₄Pt₂ octahedron. Two rhodium and two platinum atoms bound to the diphosphine ligands in 2 are nonplanar to give an octahedral C₂ symmetric Ru₂Rh₂Pt₂(dppm)₂ framework. The ³¹P NMR investigation of 1 and 2 (1D, ³¹P COSY, ³¹P–{¹⁰³Rh} HMQC) and simulation of 1D spectral patterns showed that in both clusters the structures of the M₆(PP)₂ fragments found in the solid state are maintained in solution.