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Pyridine-enabled copper-promoted cross dehydrogenative coupling of C(sp2)-H and unactivated C(sp3)-H bonds.

ABSTRACT: The pyridine-enabled cross dehydrogenative coupling of sp2 C-H bonds of polyfluoroarenes and unactivated sp3 C-H bonds of amides was achieved via a copper-promoted process with good functional group compatibility. This reaction showed great site-selectivity by favoring the sp2 C-H bonds ortho to two fluoro atoms of arenes and the sp3 C-H bonds of ?-methyl groups over those of the ?-methylene, ?- or ?-methyl groups of the aliphatic amides. Mechanistic studies revealed that sp3 C-H bond cleavage is an irreversible but not the rate-determining step, and the sp2 C-H functionalization of arenes appears precedent to the sp3 C-H functionalization of amides in this process.

SUBMITTER: Wu X

PROVIDER: S-EPMC5950755 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Pyridine-enabled copper-promoted cross dehydrogenative coupling of C(sp2)-H and unactivated C(sp3)-H bonds.

Wu Xuesong X Zhao Yan Y Ge Haibo H

Chemical science 20150720 10

The pyridine-enabled cross dehydrogenative coupling of sp2 C-H bonds of polyfluoroarenes and unactivated sp3 C-H bonds of amides was achieved via a copper-promoted process with good functional group compatibility. This reaction showed great site-selectivity by favoring the sp2 C-H bonds ortho to two fluoro atoms of arenes and the sp3 C-H bonds of α-methyl groups over those of the α-methylene, β- or γ-methyl groups of the aliphatic amides. ...[more]

PMID: 29861919

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