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Ruthenium-Catalyzed Dehydrogenation Through an Intermolecular Hydrogen Atom Transfer Mechanism.

ABSTRACT: The direct dehydrogenation of alkanes is among the most efficient ways to access valuable alkene products. Although several catalysts have been designed to promote this transformation, they have unfortunately found limited applications in fine chemical synthesis. Here, we report a conceptually novel strategy for the catalytic, intermolecular dehydrogenation of alkanes using a ruthenium catalyst. The combination of a redox-active ligand and a sterically hindered aryl radical intermediate has unleashed this novel strategy. Importantly, mechanistic investigations have been performed to provide a conceptual framework for the further development of this new catalytic dehydrogenation system.

SUBMITTER: Huang L

PROVIDER: S-EPMC8048662 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Photoinduced Acylations Via Azolium-Promoted Intermolecular Hydrogen Atom Transfer.

Project description:Photoinduced hydrogen atom transfer (HAT) has been developed as a powerful tool to generate synthetically valuable radical species. The direct photoexcitation of ketones has been known to promote HAT or to generate acyl radicals through Norrish-type pathways, but these modalities remain severely limited by radical side reactions. We report herein a catalyst- and transition metal-free method for the acylation of C-H bonds that leverages the unique properties of stable, isolable acyl azolium species. Specifically, acyl azolium salts are shown to undergo an intermolecular and regioselective HAT upon LED irradiation with a range of substrates bearing active C-H bonds followed by C-C bond formation to afford ketones. Experimental and computational studies support photoexcitation of the acyl azolium followed by facile intersystem crossing to access triplet diradical species that promote selective HAT and radical-radical cross-coupling.

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| S-EPMC2596074 | biostudies-literature

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| S-EPMC395990 | biostudies-literature

A ruthenium-catalyzed, atom-economical synthesis of nitrogen heterocycles.

Project description: Not available

| S-EPMC2888904 | biostudies-literature

Ruthenium-catalyzed intermolecular alkene-alkyne couplings in biologically relevant media.

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| S-EPMC10266458 | biostudies-literature

Concerted hydrogen atom and electron transfer mechanism for catalysis by lysine-specific demethylase.

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