Novel Effective Racemoselective Method for the Synthesis of <i>ansa</i>-Zirconocenes and Its Use for the Preparation of <i>C</i><sub>2</sub>-Symmetric Complexes Based on 2-Methyl-4-aryltetrahydro(<i>s</i>)indacene as Catalysts for Isotactic Propylene Polymerization and Ethylene–Propylene Copolymerization
2012-06-11T00:00:00Z (GMT) by
A general and effective method for the racemoselective synthesis of bis-indenyl-type <i>ansa</i>-zirconocenes was proposed and successfully applied for the synthesis of several <i>C</i><sub>2</sub>-symmetric <i>ansa</i>-zirconocenes based on 2-methyl-4-aryltetrahydro-<i>s</i>-indacene. This new racemoselective method relies on ZrCl<sub>3</sub>NH-<i>tert</i>-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.