Synthesis, structural analysis of the hetero-bimetallic complexes MMe[(O-2,4-tBu2C6H2-6-CH2)2(μ2-O-2,4-tBu2C6H2-6-CH2)N][Me2Al(μ2-OiPr)] [M = Zr, Hf] and their use in catalysis for ethylene polymerisation

Abstract

The synthesis and structural analysis of the hetero-bimetallic M–Al complexes MMe[(O-2,4-^tBu₂C₆H₂-6-CH₂)₂(μ₂-O-2,4-^tBu₂C₆H₂-6-CH₂)N][Me₂Al(μ₂-OⁱPr)] [M = Zr, Hf], prepared from M(OⁱPr)[{(O-2,4-^tBu₂C₆H₂)-6-CH₂}₃N] by treating with 1.0 equiv. of AlMe₃, have been explored: these complexes exhibited catalytic activities for ethylene polymerisation in n-octane in the presence of methylaluminoxane (MAO). The Zr–Al analogue showed high catalytic activities affording polymers with unimodal molecular weight distributions.