An Iridium(IV) Species, [Cp*Ir(NHC)Cl]+, Related to a Water-Oxidation Catalyst

被引：121

作者：

Brewster, Timothy P. ^{[1
]}

Blakemore, James D. ^{[1
]}

Schley, Nathan D. ^{[1
]}

Incarvito, Christopher D. ^{[1
]}

Hazari, Nilay ^{[1
]}

Brudvig, Gary W. ^{[1
]}

Crabtree, Robert H. ^{[1
]}

机构：

[1] Yale Univ, Dept Chem, New Haven, CT 06520 USA

来源：

ORGANOMETALLICS | 2011年 / 30卷 / 05期

关键词：

HETEROCYCLIC CARBENE LIGANDS; C-H ACTIVATION; PHOTOSYSTEM-II; ARTIFICIAL PHOTOSYNTHESIS; MOLECULAR RECOGNITION; COMPLEXES; CHEMISTRY; ALCOHOLS; ENERGY; OXYGEN;

D O I：

10.1021/om101016s

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The Ir precatalyst (3) contains both a Cp* and a kappa C-2(2),C-2'-1,3-diphenylimidazol-2-ylidene ligand, a C-C chelate, where one C donor is the NHC and the other is a cyclometalated N-phenyl wingtip group. The structure of 3 was confirmed by X-ray crystallography. Like our other recently described Cp*Ir catalysts, this compound is a precursor to a catalyst that can oxidize water to dioxygen. Electrochemical characterization of the new compound shows that it has a stable iridium(IV) oxidation state, [Cp*Ir-IV(NHC)Cl](+), in contrast with the unstable Ir(IV) state seen in our previous cyclometalated [Cp*Ir-III(2-pyridyl-2'-phenyl)Cl] catalyst. The new iridium(IV) species has been characterized by EPR spectroscopy and has a rhombic symmetry, a consequence of the ligand environment. These results both support previous studies which suggest that Cp*Ir catalysts can be advanced through the relevant catalytic cycle(s) in one-electron steps and help clarify the electrochemical behavior of this class of water-oxidation catalysts.

引用

页码：965 / 973

页数：9

共 61 条

[31] Manganese Catalysts with Molecular Recognition Functionality for Selective Alkene Epoxidation [J].