Patent ID: 7750097

Claim:
A catalyst system for preparing isotactic polyolefins are obtained by reacting at least one chiral coordination compound and at least one cocatalyst, the cocatalyst being able to convert the chiral coordination compound into a species comprising polymerization activity towards at least one olefin, wherein the chiral coordination compound is of formula (I), or an enantiomer thereof of formula (I*): wherein M is Si or Ge; Z are identical or different, and are each an organic or inorganic radical; n1, n2 are identical or different, and are each 0 or 1; R 1 and R 2 are identical or different, and are each a C 1 -C 40 radical, or R 1 and R 2 together with the atoms connecting them form a cyclic or polycyclic ring system optionally comprising at least one, identical or different, heteroatom selected from the group consisting of N, O, P, S and Si; R 3 is hydrogen or a C 1 -C 40 radical, wherein R 3 displays a lower steric hindrance than R 1 ; R 4 is hydrogen or a C 1 -C 40 radical, wherein R 4 displays a lower steric hindrance than R 2 ; R 5 and R 6 are identical or different, and are each hydrogen or a C 1 -C 40 radical; or R 1 and R 3 , R 2 and R 4 , R 1 and R 5 and/or R 2 and R 6 together with the atoms connecting them in each case form a cyclic or polycyclic ring system optionally comprising at least one, identical or different heteroatom selected from the group consisting of N, 0 , P, S and Si; X is a single bond or a divalent group; Y 1 , Y 2 are identical or different, and are each oxygen, sulfur, selenium, tellurium, NR 9 , or PR 9 ; R 7 , R 8 , R 9 are identical or different, and are each hydrogen, a C 1 -C 20 -alkyl, a C 2 -C 20 -alkenyl, a C 6 -C 22 -aryl, or an alkylaryl or arylalkyl comprising from 1 to 10 carbon atoms in the alkyl radical and from 6 to 22 carbon atoms in the aryl radical; and T 1 , T 2 , T 3 and T 4 are identical or different, and are each hydrogen or a C 1 -C 40 radical, or T 1 and T 3 and/or T 2 and T 4 together with the carbon atoms connecting them in each case form a cyclic or polycyclic ring system optionally comprising at least one, identical or different heteroatom selected from the group consisting of N, O, P, S and Si.