Novel Effective Racemoselective Method for the Synthesis of <i>ansa</i>-Zirconocenes and Its Use for the Preparation of <i>C</i>₂-Symmetric Complexes Based on 2-Methyl-4-aryltetrahydro(<i>s</i>)indacene as Catalysts for Isotactic Propylene Polymerization and Ethylene–Propylene Copolymerization

A general and effective method for the racemoselective synthesis of bis-indenyl-type ansa-zirconocenes was proposed and successfully applied for the synthesis of several C2-symmetric ansa-zirconocenes based on 2-methyl-4-aryltetrahydro-s-indacene. This new racemoselective method relies on ZrCl3NH-tert-Bu as a key reagent. The formation of racemic products was confirmed by NMR studies and single-crystal X-ray diffraction. The novel complexes are potent catalysts for isotactic propylene polymerization and ethylene–propylene copolymerization.