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Cobalt-Catalyzed, Aminoquinoline-Directed Functionalization of Phosphinic Amide sp2 C-H Bonds.

ABSTRACT: In this paper, we introduce arylphosphinic acid aminoquinoline amides as competent substrates for cobalt-catalyzed sp2 C-H bond functionalization. Specifically, the feasibility of their coupling with alkynes, alkenes, and allyl pivalate has been demonstrated. Reactions are catalyzed by simple Co(NO3)2 hydrate in ethanol or mixed dioxane/tBuOH solvent in the presence of Mn(OAc)3·2H2O additive, sodium pivalate, or acetate base and use oxygen from the air as an oxidant. Directing group removal affords ortho-functionalized P,P-diarylphosphinic acids.

SUBMITTER: Nguyen TT

PROVIDER: S-EPMC4980089 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Cobalt-Catalyzed, Aminoquinoline-Directed Functionalization of Phosphinic Amide sp2 C-H Bonds.

Nguyen Tung Thanh TT Nguyen Tung Thanh TT Grigorjeva Liene L Daugulis Olafs O

ACS catalysis 20151222 2

In this paper, we introduce arylphosphinic acid aminoquinoline amides as competent substrates for cobalt-catalyzed sp2 C-H bond functionalization. Specifically, the feasibility of their coupling with alkynes, alkenes, and allyl pivalate has been demonstrated. Reactions are catalyzed by simple Co(NO3)2 hydrate in ethanol or mixed dioxane/tBuOH solvent in the presence of Mn(OAc)3·2H2O additive, sodium pivalate, or acetate base and use o ...[more]

PMID: 27525171

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