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Electron-Rich CpIr(biphenyl-2,2'-diyl) Complexes with ?-Accepting Carbon Donor Ligands.

ABSTRACT: Cp*IrIII and CpIrIII complexes have attracted interest as catalysts for oxidative transformations, and highly oxidizing iridium species are postulated as key intermediates in both catalytic water and C-H bond oxidation. Strongly electron-donating ligand sets have been shown to stabilize IrIV complexes. We describe the synthesis and reactivity of complexes containing the CpIr(biphenyl-2,2'-diyl) moiety stabilized by a series of strong donor carbon-based ligands. The oxidation chemistry of these complexes has been characterized electrochemically, and a singly oxidized IrIV species has been observed by X-band EPR for the complex CpIr(biph)(p-CNCH2SO2C6H4CH3).

SUBMITTER: Graeupner J

PROVIDER: S-EPMC3902143 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Electron-Rich CpIr(biphenyl-2,2'-diyl) Complexes with π-Accepting Carbon Donor Ligands.

Graeupner Jonathan J Brewster Timothy P TP Blakemore James D JD Schley Nathan D ND Thomsen Julianne M JM Brudvig Gary W GW Hazari Nilay N Crabtree Robert H RH

Organometallics 20121001 20

Cp*IrIII and CpIrIII complexes have attracted interest as catalysts for oxidative transformations, and highly oxidizing iridium species are postulated as key intermediates in both catalytic water and C-H bond oxidation. Strongly electron-donating ligand sets have been shown to stabilize IrIV complexes. We describe the synthesis and reactivity of complexes containing the CpIr(biphenyl-2,2'-diyl) moiety stabilized by a series of strong donor carbon-based ligands. T ...[more]

PMID: 24474841

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