220098-86-2Relevant articles and documents
Phosphorus-bridged ansa-metallocene complexes of titanium, zirconium, and hafnium: The syntheses and structures of [PhP(C5Me4)2]MX2 and [Ph(E)P(C5Me4)2]MX2 (E = O, S, Se) derivatives
Shin, Jun Ho,Hascall, Tony,Parkin, Gerard
, p. 6 - 9 (2008/10/08)
A series of phosphorus-bridged ansa-metallocene complexes of titanium, zirconium, and hafnium, [PhP(C5Me4)2]MX2 and [Ph(E)P(C5Me4)2]MX2 (X = Cl, Me, CO, (Se3)0.5, (Te3)0.5; E = O, S, Se), has been synthesized. Structural characterization by X-ray diffraction indicates that, in comparison to their non-ansa counterparts (C5Me5)2MX2, the cyclopentadienyl groups in phosphorus-bridged complexes are displaced from symmetric η5-coordination toward η3-coordination. Such η3,η3-coordination creates more electrophilic metal centers than those in their permethylcyclopentadienyl counterparts, as judged by the v(CO) stretching frequencies of the zirconium dicarbonyl complexes Cp*2Zr(CO)2 (1946 and 1853 cm-1) and [PhP(C5Me4)2]Zr(CO)2 (1959 and 1874 cm-1).