Racemoselective synthesis of rac-diorganosilylbis(2-methylbenzoeindeyl)zirconium compounds

摘要

The present invention relates to a specific process for the diastereoselective synthesis of rac-diorganosilylbis(2-methylbenzo[e]indenyl)zirconium compounds of the formula I,; by reacting the silyl-bridged bisindenyl ligand with a dihalozirconium bis(3,5-di-tert-butylphenoxide)-base adduct to form the diorganosilylbis(2-methylbenzo[e]indenyl)zirconium bis(3,5-di-tert-butylphenoxide) and subsequently replacing the phenoxide groups by X using suitable replacement reagents to give the compound of the formula I; where the substituents X can be identical or different and are each F, Cl, Br, I or linear, cyclic or branched C_1-10-alkyl; and the substituents R can be identical or different and are each linear, cyclic or branched C_1-10-alkyl or C_6-10-aryl; and also to the use of these compounds as catalysts.