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Redox Non-Innocent Behavior of a Terminal Iridium Hydrazido(2-) Triple Bond.

ABSTRACT: The synthesis of the first terminal Group 9 hydrazido(2-) complex, Cp*IrN(TMP) (6) (TMP=2,2,6,6-tetramethylpiperidine) is reported. Electronic structure and X-ray diffraction analysis indicate that this complex contains an Ir-N triple bond, similar to Bergman's seminal Cp*Ir(Nt Bu) imido complex. However, in sharp contrast to Bergman's imido, 6 displays remarkable redox non-innocent reactivity owing to the presence of the N? lone pair. Treatment of 6 with MeI results in electron transfer from N? to Ir prior to oxidative addition of MeI to the iridium center. This behavior opens the possibility of carrying out facile oxidative reactions at a formally IrIII metal center through a hydrazido(2-)/isodiazene valence tautomerization.

SUBMITTER: Pearce AJ

PROVIDER: S-EPMC5392362 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Redox Non-Innocent Behavior of a Terminal Iridium Hydrazido(2-) Triple Bond.

Pearce Adam J AJ Cassabaum Alyssa A AA Gast Grace E GE Frontiera Renee R RR Tonks Ian A IA

Angewandte Chemie (International ed. in English) 20161001 42

The synthesis of the first terminal Group 9 hydrazido(2-) complex, Cp*IrN(TMP) (6) (TMP=2,2,6,6-tetramethylpiperidine) is reported. Electronic structure and X-ray diffraction analysis indicate that this complex contains an Ir-N triple bond, similar to Bergman's seminal Cp*Ir(Nt Bu) imido complex. However, in sharp contrast to Bergman's imido, 6 displays remarkable redox non-innocent reactivity owing to the presence of the Nβ lone pair. Treatment of 6 with MeI results in ele ...[more]

PMID: 27654844

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