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Mechanistic studies on intramolecular C-H trifluoromethoxylation of (hetero)arenes via OCF3-migration.

ABSTRACT: The one-pot two-step intramolecular aryl and heteroaryl C-H trifluoromethoxylation recently reported by our group has provided a general, scalable, and operationally simple approach to access a wide range of unprecedented and valuable OCF3-containing building blocks. Herein we describe our investigations to elucidate its reaction mechanism. Experimental data indicate that the O-trifluoromethylation of N-(hetero)aryl-N-hydroxylamine derivatives is a radical process, whereas the OCF3-migration step proceeds via a heterolytic cleavage of the N-OCF3 bond followed by rapid recombination of a short-lived ion pair. Computational studies further support the proposed ion pair reaction pathway for the OCF3-migration process. We hope that the current study would provide useful insights for the development of new transformations using versatile N-(hetero)aryl-N-hydroxylamine synthons.

SUBMITTER: Lee KN

PROVIDER: S-EPMC4909548 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Mechanistic studies on intramolecular C-H trifluoromethoxylation of (hetero)arenes via OCF3-migration.

Lee Katarzyna N KN Lei Zhen Z Morales-Rivera Cristian A CA Liu Peng P Ngai Ming-Yu MY

Organic & biomolecular chemistry 20160601 24

The one-pot two-step intramolecular aryl and heteroaryl C-H trifluoromethoxylation recently reported by our group has provided a general, scalable, and operationally simple approach to access a wide range of unprecedented and valuable OCF3-containing building blocks. Herein we describe our investigations to elucidate its reaction mechanism. Experimental data indicate that the O-trifluoromethylation of N-(hetero)aryl-N-hydroxylamine derivatives is a radical process, whereas the OCF3-migration ste ...[more]

PMID: 27043815

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