Metallocenes and catalysts for olefin-polymerisation

Claim 1

A metallocene of formula (I): (ZR 1 m ) n (Cp)(A) r ML p L′ q (I) wherein (ZR 1 m ) n is a divalent group bridging Cp and A, Z is selected from the group consisting of C, Si, Ge, N, or P, and each R 1 is independently selected from the group consisting of hydrogen, linear or branched, saturated or unsaturated C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 6 -C 20 aryl, C 7 -C 20 alkylaryl, and C 7 -C 20 arylalkyl groups, Cp is a heterocyclic cyclopentadienyl group of formula (IIa), (II′a), (IIb), or (II′b), or Cp is a partially hydrogenated derivative of the heterocyclic group of formula (IIa), (II′a), (IIb), or (II′b): wherein X or Y is selected from the group consisting of O, S, NR 6 , and PR 6 wherein R 6 is selected from the group consisting of hydrogen, a linear or branched, saturated or unsaturated C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 6 -C 20 aryl, C 7 -C 20 alkylaryl, and C 7 -C 20 arylalkyl group, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements; R 2 and R 3 , the same or different from each other, are selected from the group consisting of hydrogen, halogen, linear or branched, saturated or unsaturated C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 6 -C 20 aryl, C 7 -C 20 alkylaryl, C 7 -C 20 arylalkyl, —OR 6 , —OCOR 6 , —SR 6 , —NR 6 2 , wherein R 6 has the meaning reported above; or R 2 and R 3 from together a condensed C 5 -C 7 ring, saturated, unsaturated, or aromatic, optionally containing one or more atoms belonging to groups 13-16 of the Periodic Table of the Elements; the substituents R 4 , the same or different from each other, are selected from the group consisting of halogen, linear or branched, saturated or unsaturated C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 6 -C 20 aryl, C 7 -C 20 alkylaryl, C 7 -C 20 arylalkyl, OR 6 , —OCOR 6 , —SR 6 , —NR 6 2 , and —PR 6 2 , wherein R 6 has the meaning reported above; a is an integer ranging from 0 to 4; A is a substitued or unsubstituted cyclopentadienyl, —NR 6 wherein R 6 has the meaning reported above, corresponds to formula (IIa), (II′a), (IIb), or (II′b), or corresponds to a partially hydrogenated derivative of formula (IIa), (II′a), (IIb), or (II′b); M is a transition metal belonging to group 3, 4, 5, 6 or to the lanthanide or actinide groups of the Periodic Table of the Elements; each substituent L is independently a monoanionic sigma ligand selected from the group consisting of hydrogen, halogen, —R 6 , —OR 6 , —OCOR 6 , —OSO 2 CF 3 , —SR 6 , —NR 6 2 , and PR 6 2 , wherein each R 6 group, the same or different from each other, has the meaning reported above; each substituent L′ is independently a Lewis base; m is 1 or 2, being 1 when Z is N or P, and being 2 when Z is C, Si, or Ge; n is an integer ranging from 0 to 4; r is 0 when r is 0; p and q are integers ranging from 0 to 3, p being equal to the valence of the metal M minus when r=1, and minus 1 when r=0, and p+q being ≦3.