Some transition metal complexes of pentakis(methoxycarbonyl)cyclopentadiene: water-soluble metallocenes, and the X-ray crystal structure of Ru(η-C5H5)[η-C5(CO2Me)5]
Abstract
Some metal derivatives of the [C5(CO2Me)5]– anion (cpp–) are described, of which transition metal complexes M(cpp)2 are fully ionised in aqueous solution and the mixed complex Ru(η-C5H5)[η-C5(CO2Me)5] contains a symmetrically bonded cpp ring; covalent Group IB metal complexes M1(cpp)(PPh3) react further with PPh3 to give ionic [M(PPh3)2](cpp).