Dendritic β-diketiminato titanium and zirconium complexes: synthesis and ethylene polymerisation

The cyclopentadienyl(β-diketiminato)titanium and zirconium chlorides (η5-C5H5)MCl2(CH(C(NC6H4-4-OR)CH3)2) (M = Ti (4-dend), Zr (5-dend)), where R corresponds to the first generation carbosilane dendron (dendritic wedge) Si(CH2CH2SiMePh2)3, have been synthesised. After activation with methylaluminoxane, the activity of 4-dend and 5-dend as catalysts for ethylene polymerisation has been determined and compared with that of the non-dedritic counterpart (η5-C5H5)MCl2(CH(C(NC6H5)CH3)2) (M = Ti (4), Zr (5)).