Expanding the Origin of Stereocontrol in Propene Polymerization Catalysis

Originally developed on heterogeneous Ziegler Natta (ZN) catalysts, the model of chiral growing chain conformation developed by Corradini to explain the origin of stereocontrol in propene polymerization was extended to all stereoselective polymerization catalysts. The idea that the chiral recognition is performed by the site-chirality through the conformation of growing chain represents the marker of ZN toward, for example, asymmetric catalysis in which a chiral host molecule recognizes directly two enantiomeric guest molecules. In this paper, by using DFT calculations, we show that the origin of the stereocontrol for the new generation of Hf(IV)pyridylamido-based catalysts is somewhat different and more similar to the asymmetric catalysis.