Chain and cluster models of methylaluminoxane as activators of zirconocene hydride, alkyl and metallacyclopropane intermediates in alkene transformations

Abstract

The reactions of zirconocene hydride, alkyl, and metallacyclopropane intermediates with chain and cluster models of methylaluminoxane (MAO) have been studied using a quantum chemical approach (DFT). These reactions are considered as possible activation steps of the key intermediates in various olefin transformations. Complexes with MAO differing in the structure and stability were tested for the propene insertion stage for which thermodynamic and activation parameters were determined. Comparative analysis of the results demonstrated a significant role of chain and cage MAO structures in the formation of the sites most active toward the alkene.