Patent ID: 6992204
Filing Date: 2006-01-31
Classification: C07B,C07F,C08F,Y10S

Abstract:
1. A process for preparing racemic metallocene complexes by reacting bridged or unbridged transition metal-aromatic complexes of the formula I where the substituents and indices have the following meanings: M is titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten or an element of transition group III of the Periodic Table or a lanthanide, X are identical or different and are each fluorine, chlorine, bromine, iodine, hydrogen, C n is an integer from 1 to 4, where n corresponds to the valence of M minus 2, R R R Y, Y  ═BR with cyclopentadienyl derivatives of alkali metals or alkaline earth metals, heating the reaction mixture obtained in this way to from 75 to 180° C. with or without addition of free radicals or free radical formers, and, optionally, subsequently replacing the bridged phenolic ligand or the two unbridged phenolic ligands to form the monosubstitution or disubstitution product.