Patent ID: 6239299
Filing Date: 2001-05-29
Classification: C07F,C08F,Y10S

Abstract:
A metallocene of the formula I ##STR12##where M is a metal selected from the group consisting of Ti, Zr, Hf, V, Nb and Ta or an element selected from the group consisting of the lanthanides,X.sub.1 and X.sub.2 are identical or different and are each a C.sub.1 -C.sub.10 -alkyl group, a C.sub.1 -C.sub.10 -alkoxy group, a C.sub.6 -C.sub.10 -aryl group, a C.sub.6 -C.sub.10 -aryloxy group, a C.sub.2 -C.sub.10 -alkenyl group, a C.sub.7 -C.sub.20 -arylalkyl group, a C.sub.7 -C.sub.20 -alkylaryl group, a C.sub.8 -C.sub.20 -arylalkenyl group, hydrogen or a halogen atom,L.sub.1 and L.sub.2a) are identical or different and are each an unsubstituted, monosubstituted or polysubstituted monocyclic or polycyclic hydrocarbon radical containing at least one cyclopentadienyl unit which can form a sandwich structure with M, orb) L.sub.1 is an unsubstituted, monosubstituted or polysubstituted monocyclic or polycyclic hydrocarbon radical containing at least one cyclopentadienyl unit which can form a sandwich structure with M, and L.sub.2 is an amido, phosphido or arsenido radical of the formula ##STR13##where D is nitrogen, phosphorus or arsenic and E is as defined for X.sub.1 and X.sub.2,R is carbon, silicon, germanium or tin,A and B are identical or different and are ferrocenyl-substituted radicals of the formula ##STR14##where R' is a C.sub.1 -C.sub.10 -alkyl group, a C.sub.6 -C.sub.10 -aryl group, a C.sub.2 -C.sub.10 -alkenyl group, a C.sub.7 -C.sub.20 -arylalkyl group, a C.sub.7 -C.sub.20 -alkylaryl group or a C.sub.8 -C.sub.20 -arylalkenyl group, where B can also be as defined for X.sub.1 or X.sub.2.