ansa-Metallocene derivatives XXXIII. 2-Dimethylamino-substituted bis-indenyl zirconium dichloride complexes with and without a dimethylsilyl bridge: syntheses, crystal structures and properties in propene polymerization catalysis

摘要: Abstract Bis(2-N,N-dimethylamino-indenyl) zirconium dichloride, (2-(CH 3 ) 2 N-C 9 H 6 ZrCl , and dimethylsilyl-bridged bis(2-N,N-dimethylamino-indenyl) (CH Si(2-(CH 5 were prepared by reaction of the corresponding ligand lithium salts with 4 in toluene. Diffractometric structure determinations reveal C -symmetric complex geometries for both complexes. An increased electron density at Zr center dimethylamino-substituted complexes is indicated reduction potentials which are 0.3–0.4 V more negative than those their unsubstituted analogs. When activated methyl aluminoxane toluene solution, catalyzes polymerization propene to polymers a microstructure comparable that produced other Me Si-bridged bis(indenyl)ZrCl complexes, but substantially fraction i-propyl end groups derived from alkyl exchange between Zr-polymer AlMe species.