A new series of zirconium metallocenes derived from partially alkylated s-indacene with potential applications in the polymerization of ethylene

Abstract This contribution describes the synthesis and characterization of a series of zirconium metallocenes derived from partially alkylated s -indacene. The complexes [Cp ∗ ZrCl 2 - s -Ic″H] 1 , [Cp ∗ ZrCl 2 - s -Ic″H] 3 and [CpZrCl 2 - s -Ic″H] 4 ( s -Ic′H = 2,6-diethyl-4,8-dimethyl-1-hydro- s -indacene; s -Ic″H = 2,6-dibutyl-4,8-dimethyl-1-hydro- s -indacene) were synthesized from the monolithiated salts of s -indacene ( s -Ic′H or s -Ic″H) with one equivalent of C 5 R 5 ZrCl 3 (R = H, CH 3 ). All complexes here reported were characterized by means of 1 H and 13 C NMR, mass spectrometry, elemental analysis. Complexes [Cp ∗ ZrCl 2 - s -Ic′H] 1 and [CpZrCl 2 - s -Ic′H] 2 (previously reported by NMR analysis) were characterized by X-ray diffraction. In order to gain further knowledge about their catalytic behavior, the complexes were tested in the catalysis of ethylene polymerization showing a highest activity. Complex 4 presents the highest ethylene polymerization activity than complexes 1 and 2 , and 3 under the same working conditions.