A carbon-free sandwich complex [(P5)2Ti]2-.
Reactions of highly reduced titanium complexes with white phosphorus, P4, at or below 25 degrees C yielded brown to deep red-brown salts of the first entirely inorganic metallocene, [(eta5-P5)2Ti](2-)(1). Like ferrocene and other carbon-based metallocenes, the structure of 1 has parallel and planar five-membered rings symmetrically positioned about the central metal atom. Despite its electron-deficient (16 electron) and formally zerovalent titanium character, salts of 1 are highly stable toward heat and air, both in solution and in the solid state. Computational studies show that the pentaphosphacyclopentadienyl unit, P5, functions as an unusually effective acceptor ligand, and this results in substantial stabilization of 1.
Urnius
Eugenijus
E
Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA. urnezius@mtu.edu
Brennessel
William W
WW
Cramer
Christopher J
CJ
Ellis
John E
JE
Schleyer
Paul von Ragué
Pv