Concerning the reaction of zirconocene dichloride and methylalumoxane: Homogeneous Ziegler‐Natta catalytic system for olefin polymerization

The interaction of zirconocene dichloride (Cp 2 ZrCl 2 ) with methylalumoxane (MAO), the two components of homogeneous catalyst for olefin polymerization, was studied by 1 H NMR spectroscopy. Its was found that Cp 2 ZrCl 2 is monoalkylated by Al 2 (CH 3 ) 6 present in MAO. The trimethylaluminium contained in MAO appears to be the active species in the alkylation of the zirconocene dichloride. The Cp 2 ZrCH 3 Cl likely forms, with an excess of MAO, highly polarized species. These are decomposed by a complexing agent of MAO such as KCl.