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Copper-promoted site-selective carbonylation of sp³ and sp² C-H bonds with nitromethane.

ABSTRACT: Copper-promoted direct carbonylation of unactivated sp³ C-H and aromatic sp² C-H bonds of amides was developed using nitromethane as a novel carbonyl source. The sp³ C-H functionalization showed high site-selectivity by favoring the C-H bonds of ?-methyl groups. The sp² C-H carbonylation featured high regioselectivity and good functional group compatibility. Kinetic isotope effect studies indicated that the sp³ C-H bond breaking step is reversible, whereas the sp² C-H bond cleavage is an irreversible but not the rate-determining step. Control experiments showed that a nitromethyl intermediate should be involved in the present reaction.

SUBMITTER: Wu X

PROVIDER: S-EPMC6020547 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Copper-promoted site-selective carbonylation of sp3 and sp2 C-H bonds with nitromethane.

Wu Xuesong X Miao Jinmin J Li Yanrong Y Li Guigen G Ge Haibo H

Chemical science 20160426 8

Copper-promoted direct carbonylation of unactivated sp3 C-H and aromatic sp2 C-H bonds of amides was developed using nitromethane as a novel carbonyl source. The sp3 C-H functionalization showed high site-selectivity by favoring the C-H bonds of α-methyl groups. The sp2 C-H carbonylation featured high regioselectivity and good functional group compatibility. Kinetic isotope effect studies indicated that the sp3 C-H bond breaking step is reve ...[more]

PMID: 30155175

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