Electronic Properties of a Cationic Triphenylphosphine Ligand Decorated with a (η5‑C5H5)Fe Group in Late-Transition-Metal Complexes

The synthesis and characterization of a series of novel cationic multimetallic transition-metal complexes based on the cationic phosphine ligand (η6-diphenylphosphinobenzene)­(η5-cyclopentadienyl)­iron­(II) hexafluorophosphate (1) are reported. Complexes of ligand 1 with the late transition metals ruthenium, osmium, rhodium, and iridium as well as palladium and platinum were isolated in generally good yields, and the solid-state structures of most of them were determined. On the basis of the 195Pt–31P NMR coupling constant measured for trans-(1)2PtCl2 and the carbonyl absorption band in the IR spectrum of trans-(1)2Rh­(CO)­Cl, the electronic influence of the ligand on the metal center was evaluated. These measurements are supported by density functional theory (DFT) calculations, performed on the corresponding tricarbonylnickel(0) complex in order to determine the Tolman electronic parameter (TEP) of ligand 1.