Synthesis and organic group transfer of organodiplatinum complex with a 1,2-bis(diphenylphosphino)ethane ligand
A series of homometallic alkyl- and phenyldinuclear complexes containing one platinum–platinum bond, (dppe)RPt–Pt(η5-Cp)(CO) (R = Me, Et, CH2CMe3, Ph), have been prepared by oxidative addition of the Pt–C bond of PtR(η5-Cp) to Pt(styrene)(dppe), and were characterized by spectroscopic methods and (or) X-ray structure analysis. The geometry at Pt with a dppe ligand is square planar, and the carbonyl and Cp ligand of the Pt(η5-Cp)(CO) moiety lie orthogonal to the coordination plane of former platinum. Competitive organic group transfer reactions along the Pt–Pt bond in these complexes took place to give PtR(η5-Cp)(CO) and PtR(η1-Cp)(dppe) on thermolysis. Alkyl or aryl transfer from Pt with a dppe ligand were enhanced by addition of olefin, whereas treatment with CO and tertiary phosphine ligands causes Cp transfer from Pt(η5-Cp)(CO).Key words: organoplatinum–platinum complex, organic group transfer.