Indirect metal-metal linkage: Cyclic ferrocene complexes with a second metal linked via remote phosphine functionality

Article abstract of DOI:10.1021/ic50224a015

The synthesis of the heterodifunctional ligand (C₆H₅)₂PCH₂Si(CH₃) ₂C₅H₄Li (1) is described, and its utilization as a building block for the preparation of cyclic dinuclear complexes containing dissimilar transition metals is explored. The ferrocene (2) derived from 1 is found to coordinate with Mo(CO)₄, Mn(CO)₃Br, NiCl₂, NiBr₂, and Co₂(CO)₆ fragments through its two phosphine groups. Steric constraints lead exclusively to higher cyclic oligomers in the Mo and Mn complexes and have unusual stereochemical consequences in the Ni systems. The normal chemistry of the Co-Co fragment is unaffected by complexation with diphosphine 2. An evaluation of the suitability of 1 and related ligands for the construction of different types of heterodinuclear complexes is presented.