Synthesis, Characterization, and Marked Polymerization Selectivity Characteristics of Binuclear Phenoxyiminato Organozirconium Catalysts

The new binuclear phenoxyiminato zirconium complex {1,7-(O)2C10H4-2,7-[CHN(2,6-iPr2C6H3)]2}Zr2Cl6(THF)2 (FI2-Zr2) polymerizes ethylene with greater activity (∼8×) than the mononuclear analogue. Also, this catalyst produces high molecular weight ethylene + 1-hexene copolymers, while the mononuclear analogue yields only traces of copolymer under identical conditions. This ability to produce copolymers suggests cooperativity between the two Zr centers which promotes 1-hexene co-enchainment.