Patent ID: 6984743

Claim:
A process for preparing a metallocene, which comprises reacting a ligand starting compound with an adduct of the formula (I), M 1 X n D a (I) wherein M 1 is a metal of group III, V or VI of the Periodic Table of the Elements or an element of the Lanthanide or actinides series and n is 2, 3, 4, 5 or 6 and corresponds to the oxidation number of the metal M 1 or where M 1 is a metal of group IV of the Periodic Table of the Elements and n is 4, and X are identical or different are each halogen, C 1 –C 10 -alkoxy-, C 8 –C 10 -aryloxy, C 1 –C 10 -alkylsulfonate, C 1 –C 10 -alkylcarboxylate, or 1,3-dicarbonylate, a is an integer or fraction and 0<a≦4 and D is a linear, cyclic or branched oligoether or polyether containing at least two oxygen atoms or an oligothioether or polythioether containing at least two sulfur atoms.