A novel neutral triple-stranded hexanuclear copper(I) cluster helicate [CuI 6L3]·2CH3CN derived from a thiosemicarbazone ligand could be synthesized and crystallographically characterized. The MALDI mass spectrum of this complex suggests that the tetranuclear copper(I) cluster helicate [CuI 4L2] is also present in solution. These copper(I) cluster helicates are capable, in the presence of O2, of hydroxylating the arene linker of their supporting ligand strands. The resulting dinuclear complex [CuII 2L’(OH)] is formed by two copper(II) centers, a new ligand arising from the hydroxylation reaction, and one hydroxide group. The magnetic investigation of this compound shows a strong antiferromagnetic coupling between the two CuII centers. The kinetic studies for the hydroxylation process show values of DH=70 kJmol1, similar to those mediated by the tyrosinase enzymes.
Endogenous Arene Hydroxylation Promoted by Copper(I) Cluster Helicates
MONZANI, ENRICO;CASELLA, LUIGI;
2010-01-01
Abstract
A novel neutral triple-stranded hexanuclear copper(I) cluster helicate [CuI 6L3]·2CH3CN derived from a thiosemicarbazone ligand could be synthesized and crystallographically characterized. The MALDI mass spectrum of this complex suggests that the tetranuclear copper(I) cluster helicate [CuI 4L2] is also present in solution. These copper(I) cluster helicates are capable, in the presence of O2, of hydroxylating the arene linker of their supporting ligand strands. The resulting dinuclear complex [CuII 2L’(OH)] is formed by two copper(II) centers, a new ligand arising from the hydroxylation reaction, and one hydroxide group. The magnetic investigation of this compound shows a strong antiferromagnetic coupling between the two CuII centers. The kinetic studies for the hydroxylation process show values of DH=70 kJmol1, similar to those mediated by the tyrosinase enzymes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
