Synthesis and reactions of some cyclopentadienyl complexes of platinum

Abstract

Reaction of PtCl(X)(COD), COD = 1,5-cyclooctadiene (X = CH3, Cl) with TlC5H5 gives η1-C5H5 complexes Pt(η1-C5H5)(Y)(COD) (Y = CH3, Cl, η1-C5H5). Pt(η1-C5H5)(CH3)(COD) is converted to Pt(η5-C5H5)(CH3)L by treatment with L = CO, P(OCH3)3, P(OC6H5)3, P(OCH3)(C6H5)2; treatment with CF3C≡CCF3 or maleic anhydride results in a Diels–Alder addition to the diene residue of the η1-C5H5 ring from the side of the ring opposite the Pt atom. Diels–Alder addition occurs between CF3C≡CCF3 and one η1-C5H5 ring of Pt(η1-C5H5)2COD; the other η1-C5H5 converts to η5 displacing the COD, and the norbornadiene is bidentate. 1H and 13C nmr data are presented for some η1 and η5-C5H5 complexes.