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Chemoselective activation of sp(3) vs sp(2) C-H bonds with Pd(II).

ABSTRACT: The first selective coupling of a carbon nucleophile with methyl, ethyl, propyl, and butyl arenes in the absence of a directing group is described. Pd(OAc)2 double C-H activation displays remarkable selectivity for the terminal methyl sites in alkyl arenes, rather than the more commonly observed arene sp(2) C-H activation. Mechanistic studies indicate the intermediacy of an azlactone dimer, obtained from oxidation with Pd(OAc)2, and are consistent with a Pd-catalyzed C-H activation vs a radical process. The observed reactivity establishes that typical reaction solvents (e.g., toluene) can readily participate in C-H activation chemistry.

SUBMITTER: Curto JM

PROVIDER: S-EPMC4304446 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Chemoselective activation of sp(3) vs sp(2) C-H bonds with Pd(II).

Curto John M JM Kozlowski Marisa C MC

Journal of the American Chemical Society 20141229 1

The first selective coupling of a carbon nucleophile with methyl, ethyl, propyl, and butyl arenes in the absence of a directing group is described. Pd(OAc)2 double C-H activation displays remarkable selectivity for the terminal methyl sites in alkyl arenes, rather than the more commonly observed arene sp(2) C-H activation. Mechanistic studies indicate the intermediacy of an azlactone dimer, obtained from oxidation with Pd(OAc)2, and are consistent with a Pd-catalyzed C-H activation vs a radical ...[more]

PMID: 25423164

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