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Understanding the differential performance of Rh2(esp)2 as a catalyst for C-H amination.

ABSTRACT: Catalytic amination of saturated C-H bonds is performed efficiently with the use of Rh(2)(esp)(2). Efforts to identify pathways for catalyst degradation and/or arrest have revealed a single-electron oxidation event that gives rise to a red-colored, mixed-valence dimer, [Rh(2)(esp)(2)](+). This species is fortuitously reduced by carboxylic acid, a byproduct generated in the reaction cycle with each turnover of the diacyloxyiodine oxidant. These findings have led to the conclusion that the high performance of Rh(2)(esp)(2) is due in part to the superior kinetic stability of its one-electron oxidized form relative to other dimeric Rh complexes.

SUBMITTER: Zalatan DN

PROVIDER: S-EPMC2827177 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Understanding the differential performance of Rh2(esp)2 as a catalyst for C-H amination.

Zalatan David N DN Du Bois J J

Journal of the American Chemical Society 20090601 22

Catalytic amination of saturated C-H bonds is performed efficiently with the use of Rh(2)(esp)(2). Efforts to identify pathways for catalyst degradation and/or arrest have revealed a single-electron oxidation event that gives rise to a red-colored, mixed-valence dimer, [Rh(2)(esp)(2)](+). This species is fortuitously reduced by carboxylic acid, a byproduct generated in the reaction cycle with each turnover of the diacyloxyiodine oxidant. These findings have led to the conclusion that the high pe ...[more]

PMID: 19441831

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