FACILE ALPHA-H ELIMINATION IN CATIONIC ZIRCONIUM ALKYL COMPLEXES - FORMATION OF MU-CH2 COMPLEXES AS A POSSIBLE DEACTIVATION PATHWAY IN POLYMERIZATION CATALYSIS

The fulvalene complex {CPZr(CH3)(2)}(2)(eta(5): eta(5)-C10H8) reacts with [CPh(3)][B(C6F5)(4)] at - 60 degrees C in the absence of donor ligands with elimination of methane, to give the dinuclear mu-CH2 complex [(CpZr)(2)(mu-CH3)(mu-CH2)(eta(5):eta(5)-C-10)H-8)](+). The relevance of this very facile (alpha-H elimination process as a pathway in the deactivation of homogeneous Ziegler catalysts is discussed.