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Capturing fleeting intermediates in a catalytic C-H amination reaction cycle.

ABSTRACT: We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C-H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abstraction pathway and raise the intriguing possibility that two catalytic C-H amination pathways may be operative in a typical bulk solution reaction. As highlighted by these results, desorption electrospray ionization MS should have broad applicability for the mechanistic study of catalytic processes.

SUBMITTER: Perry RH

PROVIDER: S-EPMC3494934 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Capturing fleeting intermediates in a catalytic C-H amination reaction cycle.

Perry Richard H RH Cahill Thomas J TJ Roizen Jennifer L JL Du Bois Justin J Zare Richard N RN

Proceedings of the National Academy of Sciences of the United States of America 20121022 45

We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C-H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abs ...[more]

PMID: 23091019

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