Site-Selective Functionalization of Unactivated C(sp3)–H Bonds via Synergistic Merger of Photoredox and HAT Catalysis

Research Square (Research Square), Год журнала: 2024, Номер unknown

Опубликована: Фев. 1, 2024

Hydrogen atom abstraction from C(sp³)−H substrates for the generation of alkyl radical represents a desirable yet underexplored strategy in alkylation reaction since involving noble metal catalysts, stoichiometric oxidants, and limited scope are common drawbacks. Here we describe synergistic utilization photoredox hydrogen transfer (HAT) catalysis to accomplish general practical functionalization unactived centers, which features broad scope, high functional group compatibility, operational simplicity. A combination validation experiments density theory reveals that N-centred radicals, generated free N−H bond via catalyzed single-electron oxidation followed by deprotonation stepwise electron/proton event, key intermediates enable an intramolecular 1,5-HAT or intermolecular HAT process nucleophilic carbon-centred radicals formation achieve heteroarylation, alkylation, amination, cyanation, azidation, trifluoromethylthiolation, halogenation deuteration. The value this protocol was further demonstrated gram-scale synthesis late-stage natural products drug derivatives.

Язык: Английский

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Halogen Promoted Desulfurative Cleavage of Cyclopropylmethyl Thioethers and Amination of the Formed Cyclopropylcarbinyl Cations

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(20)

Опубликована: Март 20, 2024

Abstract Cyclopropylmethyl sulfides react with N ‐fluorosulfonimide (NFSI) or molecular iodine, enabling C−S cleavage to generate cyclopropylcarbinyl cations, which evolve through cyclopropane ring‐opening reactions into homoallyl cations suitable nucleophiles present in the reaction media. This desulfurative of cyclopropylmethyl thioethers under non‐acidic conditions facilitates homoallylation ‐based such as alkyl aryl amines well sulfonimides a one‐pot protocol one two steps depending on nucleophile. The is initiated by halogen‐sulfur bond that causes cleavage. Moreover, iodine proceeds iodide intermediates.

Язык: Английский

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Quantifying flattening distortion on the thermodynamics and kinetics of electron transfers of Cu(i) photoredox catalysts

Inorganic Chemistry Frontiers, Год журнала: 2024, Номер 11(13), С. 4019 - 4031

Опубликована: Янв. 1, 2024

Vertical electron transfer controls the thermodynamics of Cu( i ) photoredox catalysis. Structural relaxation indirectly enhances metal-centered reductions by preventing flattening distortions destabilizing oxidized ii species.

Язык: Английский

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Oxidative Cross-Dehydrogenative C–H Bond Amination of Imidazo[1,2-a]pyridines in Aqueous Media under Metal-Free Conditions

Synthesis, Год журнала: 2024, Номер 56(19), С. 3019 - 3026

Опубликована: Июнь 19, 2024

Abstract The metal-free direct oxidative cross-dehydrogenative C–H bond amination of imidazopyridines with pyrazole in water as solvent has been developed under K2S2O8-promoted mild conditions. This strategy was applied to variable imidazoheterocycles give products moderate good yields. described protocol also offers scale-up synthesis for the construction C–N bonds, which makes it suitable biologically active compounds and pharmaceuticals.

Язык: Английский

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Visible light–driven organic synthesis under Eosin Y photocatalysis

Elsevier eBooks, Год журнала: 2024, Номер unknown, С. 91 - 149

Опубликована: Авг. 16, 2024

Язык: Английский

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