Patent ID: 6936563

Claim:
A complex of the formula I a or I b, where the variables are defined as follows: M is selected from the group consisting of Ti, Zr, Hf, V, Nb and Ta; y corresponds to the oxidation state of M minus 1; z corresponds to the oxidation state of M minus 2; Nu is selected from the group consisting of O, S and N—R 5 ; X are identical or different and are selected from the group consisting of a halogen, a C 1 -C 8 -alkyl, a C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl) and a C 6 -C 14 -aryl, R 1 to R 5 are identical or different and are selected from the group consisting of a hydrogen, a substituted C 1 -C 18 -alkyl, an unsubstituted C 1 -C 18 -alkyl, a substituted C 2 -C 18 -alkenyl having from one to 4 isolated or conjugated double bonds, an unsubstituted C 2 -C 18 -alkyl, having from one to 4 isolated or conjugated double bonds, a substituted C 3 -C 12 -cycloalkyl, an unsubstituted, C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl, an unsubstituted C 6 -C 14 -aryl, a substituted C 6 -C 14 -alkyl, wherein the substituted C 6 -C 14 -alkyl has one or more identical or different substituents selected from the group consisting of a substituted C 1 -C 18 -alkyl, an unsubstituted C 1 -C 18 -alkyl, a substituted C 1 -C 18 -alkenyl, an unsubstituted C 1 -C 18 -alkenyl, a C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl, a C 6 -C 14 -aryl, a halogen, a substituted C 1 -C 6 -alkoxy, an unsubstituted C 1 -C 6 -alkoxy, a C 6 -C 14 -aryloxy, a SiR 6 R 7 R 8 and an O—SiR 6 R 7 R 8 ; an unsubstituted five- member nitrogen-containing heteroaryl radical, a substituted five-member nitrogen-containing hetereoaryl radical, an unsubstituted six-membered nitrogen-containing heteroaryl radical wherein one or more substituents are identical or different and are selected from the group consisting of a substituted C 1 -C 18 -alkyl, an unsubstituted C 1 -C 18 -alkyl, a substituted C 2 -C 18 -alkenyl, an unsubstituted C 2 -C 18 -alkenyl, a C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl, a C 6 -C 14 -aryl, a halogen, a C 1 -C 6 -alkoxy, a C 6 -C 14 -aryloxy, a SiR 6 R 7 R 8 , and an O—SiR 6 R 7 R 8 ; where adjacent radicals R 1 to R 4 may be joined to one another to form a 5-membered to 12-membered ring which may in turn bear substituents selected from the group consisting of a substituted C 1 -C 8 -alkyl, an unsubstituted C 1 -C 8 -alkyl, a substituted C 2 -C 8 -alkenyl having from one to 4 isolated or conjugated double bonds an unsubstituted C 2 -C 8 -alkenyl having from one to 4 isolated or conjugated double bonds, a substituted C 3 -C 12 -cycloalkyl, an unsubstituted C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl, and a C 6 -C 14 -aryl; wherein R 6 to R 8 are identical or different and are selected from the group consisting of a hydrogen, a C 1 -C 8 -alkyl, a C 3 -C 12 -cycloalkyl, a C 7 -C 13 -aralkyl, and a C 6 -C 14 -aryl.