Patent ID: 7053158

Claim:
A Ziegler-Natta catalyst for olefin production wherein the catalyst is represented by the general formula [(R 1 ) n (R d ) m A(R 2 )E]MX (I) wherein: A is a carborane dianion; R 1 is H, a C 1 –C 12 -hydrocarbyl aliphatic or aromatic group and n is U or 1, said R 1 being attached to a carbon atom of A; R d is H, a C 1 –C 12 -hydrocarbyl aliphatic or aromatic group, a halide, an O-alkyl or N-alkyl group and m is 0 or an integer from 1 to 5, said R d being attached to a boron atom of A; R 2 is a constrained chiral center enriched hydrocarbyl bridge comprising at least two carbon atoms, wherein at least one bridging carbon atom may be replaced by Si; E is a heteroatom anion of group 15 or 16 of the Periodic Table (IUPAC), which is bridged to A via R 2 M is a fourvalent metal cation selected from the group consisting of titanium, zirconium, hafnium and tin; and X is a valence group saturating the remaining coordination valence of the central metal atom.