Patent ID: 6365763
Filing Date: 2002-04-02
Classification: C07F,C08F,Y10S

Abstract:
A chiral rac/meso-metallocene of the formula I having an rac/meso ratio of from >20:1 to <200:1 whereM is hafnium, the radicals X are identical or different and are each a hydrogen atom, C1-C10-alkyl, C1-C10-alkoxy, C6-C20-aryl, C6-C20-aryloxy, C2-C10-alkenyl, C7-C40-arylalkenyl C7-C40-alkylaryl or C8-C40-arylalkenyl, an OH group, a halogen atom or a pseudohalogen, the radicals R1 and R2 are identical or different, with even radicals having the same index being able to be different, and are each a hydrogen atom, C1-C10-alkyl, C1-C10-alkoxy, C6-C20-aryl, C6-C20-aryloxy, C2-C10-alkenyl, C7-C40-arylalkenyl, C7-C40-alkylaryl or C8-C40-arylalkenyl, an OH group, a halogen atom or a pseudohalogen, or a NR52, SR5, OSiR53, SiR53 or PR52 group with R5 defined as for X, the radicals R3 and R4 are identical or different, with even radicals having the same index being able to be different, and are each a hydrogen atom, C1-C10-alkyl, C1-C10-alkoxy, C6-C20-aryl, C6-C20-aryloxy, C2-C10-alkenyl, C7-C40-arylalkenyl, C7-C40-alkylaryl or C8-C40-arylalkenyl, an OH group, a halogen atom or a pseudohalogen, or an NR52, SR5, OSiR53, SiR53 or PR52 group with R5 defined as for X, or the radicals R3 and R4 together form an unsubstituted butadienyl group, Bâ€² is a bridge between the ligands, with the proviso that the radicals R1, R2, R3 and R4 are not all identical and that, if R3 and R4 together form an unsubstituted butadienyl group, R1 and R2 are hydrogen.