Dissymmetric ansa zirconocene complexes with di- and trisubstituted indenyl ligands as catalysts for homogeneous ethylene homo- and ethylene/1-hexene copolymerization reactions

Abstract Different routes for the synthesis of 1,2- and 1,2,3-substituted indene derivatives are described. Representative substituents are: Me, Ph, PhCH 2 , PhCH 2 CH 2 , PhCH 2 CH 2 CH 2 , CH 2 CH = CH 2 . Subsequent deprotonation of these substituted indenes and reaction with indenyl zirconium trichloride gave the corresponding dissymmetric bis(indenyl) zirconium complexes. After activation with methylaluminoxane (MAO) these complexes show high activities both in ethylene homopolymerisation and ethylene/1-hexene copolymerisation. The rate of comonomer incorporation can reach 33.3% ( 15 /MAO). The copolymers exhibit lower melting points than the homopolymers and their crystallinities α are lower compared with the homopolymers.