Patent ID: 6051728
Filing Date: 2000-04-18
Classification: C07F,C08F,Y10S

Abstract:
A metallocene compound of formula (I): ##STR8## wherein R.sup.1, R.sup.3, and R.sup.4, which can be identical or different, are hydrogen atoms or C.sup.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.2 -C.sub.20 -alkenyl, C.sub.6 -C.sub.20 aryl, C.sub.7 -C.sub.20 -alkylaryl, or C.sub.7 -C.sub.20 arylalkyl groups which can contain silicon or germanium atoms, provided that R.sup.3 is not a hydrogen atom;R.sup.2 is a hydrogen atom;R.sup.5 is a hydrogen atom or a --CHR.sup.7 R.sup.8 group;R.sup.6 is a C.sub.6 -C.sub.20 aryl radical or a --CHR.sup.9 R.sup.10 group;R.sup.5 and R.sup.6 can form a ring having from 3 to 8 carbon atoms which can contain hetero atoms;R.sup.7, R.sup.8, R.sup.9, and R.sup.10, which can be identical or different, are hydrogen atoms or C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.2 -C.sub.20 -alkenyl, C.sub.6 -C.sub.20 aryl, C.sub.7 -C.sub.20 -alkylaryl, or C.sub.7 -C.sub.20 arylalkyl groups which can contain hetero atoms and two R.sup.7, R.sup.8, R.sup.9, and R.sup.10 substituents can form a ring having 3 to 8 carbon atoms which can contain hetero atoms;M is an atom of a transition metal selected from the group consisting of groups 4, 5, and 6, in the Periodic Table of the Elements (new IUversion);the X substituents, which can be identical or different, are hydrogen atoms, halogen atoms, or --R, --OR, --SR, --NR.sub.2 or --PR.sub.2 groups, wherein the R substituents are C.sub.3 -C.sub.20 -cycloalkyl, C.sub.2 -C.sub.20 -alkenyl, C.sub.6 -C.sub.20 aryl, C.sub.7 -C.sub.20 -alkylaryl, or C.sub.7 -C.sub.20 arylalkyl groups which can contain silicon or germanium atoms;with the proviso that, when the R.sup.1 and R.sup.4 substituents are hydrogen atoms and the R.sup.5 and R.sup.6 substituents are methyl groups, then the R.sup.3 substituents are other than an isopropyl or tert-butyl group.