Patent ID: 7781586

Claim:
A compound of the formula I wherein L is a neutral ligand; X 1 and X 2 independently of each other are anionic ligands; R 1 is selected from the group consisting of C 1-6 -alkyl, halogen-C 1-6 -alkyl, C 1-6 -alkoxy, C 1-6 -alkylcarbonyl, aryl, hydroxy, aryloxy, nitro, amino, mono-C 1-6 -alkyl- or di-C 1-6 -alkylamino, halogen, thio, C 1-6 -alkylthio or SO 2 —C 1-6 -alkyl, SO 2 -aryl, SO 3 H, SO 3 —C 1-6 -alkyl or OSi(C 1-6 -alkyl) 3 and SO 2 —NR′R″ wherein R′ and R″ independently of each other have the meaning of hydrogen or C 1-6 -alkyl or R′ and R″ together with the N atom form a carbocycle; R 2 , R 3 , R 4 , R 5 and R 6 independently of each other are selected from the group consisting of hydrogen, C 1-6 -alkyl, halogen-C 1-6 -alkyl, C 1-6 -alkoxy, C 1-6 -alkylcarbonyl, aryl, hydroxy, aryloxy, nitro, amino, mono-C 1-6 -alkyl- or di-C 1-6 -alkylamino, halogen, thio, C 1-6 -alkylthio or SO 2 —C 1-6 -alkyl, SO 2 -aryl, SO 3 H, SO 3 —C 1-6 -alkyl or OSi(C 1-6 -alkyl) 3 and SO 2 —NR′R″ wherein R′ and R″ independently of each other have the meaning of hydrogen or C 1-6 -alkyl or R′ and R″ together with the N atom form a carbocycle; and Y is selected from the group consisting of hydrogen, C 1-6 -alkyl, C 2-6 -alkenyl and aryl, or Y and R 6 taken together to form a (CH═CR)— or a —(CH 2 ) n — bridge with n having the meaning of 2 or 3 and R is as defined for R 2 .