A sterically hindered bis-eta-alkylcyclopentadienylzirconium compound as catalyst for the polymerisation of ethene and propene

The compound bis[?-(1,3,3,5,5-pentamethylcyclohexyl)-cyclopentadienyl] zirconium dichloride has been prepared and the crystal structure determined. The compound together with the cocatalyst methylaluminoxane will catalyse the polymerisation of ethene and propene.