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Switching the site-selectivity of C-H activation in aryl sulfonamides containing strongly coordinating N-heterocycles.

ABSTRACT: The limitations of arene C-H functionalization of aryl sulfonamides containing strongly coordinating N-heterocycles were overcome using a Rh(iii) catalyst. The site-selectivity of C-H carbenoid functionalization at the ortho position relative to either the sulfonamide or N-heterocycle directing groups was elegantly switched using solvents of different polarities and different additive concentrations. Importantly, sulfonamide-group-directed ortho-C-H carbenoid functionalization tolerated strongly coordinating N-heterocycles, including pyridine, pyrrole, thiazole, pyrimidine, and pyrazine. Density functional theory (DFT) calculations were performed to rationalize the reaction mechanisms and the influence of reaction polarity.

SUBMITTER: Dong Y

PROVIDER: S-EPMC6857669 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Switching the site-selectivity of C-H activation in aryl sulfonamides containing strongly coordinating N-heterocycles.

Dong Yi Y Zhang XuePeng X Chen Jiajing J Zou Wenxing W Lin Songwen S Xu Heng H

Chemical science 20190812 38

The limitations of arene C-H functionalization of aryl sulfonamides containing strongly coordinating N-heterocycles were overcome using a Rh(iii) catalyst. The site-selectivity of C-H carbenoid functionalization at the ortho position relative to either the sulfonamide or N-heterocycle directing groups was elegantly switched using solvents of different polarities and different additive concentrations. Importantly, sulfonamide-group-directed ortho-C-H carbenoid functionalization tole ...[more]

PMID: 31762973

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