Metallaphotoredox catalysis for sp³C–H functionalizations through hydrogen atom transfer (HAT)

Chemical Society Reviews, Год журнала: 2023, Номер 52(12), С. 4099 - 4120

Опубликована: Янв. 1, 2023

sp 3 C–H functionalizations under the combination of photocatalytic HAT and transition metal catalysis.

Язык: Английский

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Radical Polarity

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Окт. 3, 2024

The polarity of a radical intermediate profoundly impacts its reactivity and selectivity. To quantify this influence predict effects, the electrophilicity/nucleophilicity >500 radicals has been calculated. This database open-shell species entails frequently encountered synthetic intermediates, including centered at sp

Язык: Английский

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Enhanced Excited-State Hydricity of Pd–H Allows for Unusual Head-to-Tail Hydroalkenylation of Alkenes

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(22), С. 12224 - 12232

Опубликована: Май 24, 2023

Photoinduced enhancement of hydricity palladium hydride species enables unprecedented addition-like (“hydridic”) hydropalladation electron-deficient alkenes, which allows for chemoselective head-to-tail cross-hydroalkenylation and electron-rich alkenes. This mild general protocol works with a wide range densely functionalized complex Notably, this approach also highly challenging cross-dimerization electronically diverse vinyl arenes heteroarenes.

Язык: Английский

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Cooperative Fe/Co-Catalyzed Remote Desaturation for the Synthesis of Unsaturated Amide Derivatives

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(7), С. 4985 - 4992

Опубликована: Фев. 6, 2024

Unsaturated amides represent common functional groups found in natural products and bioactive molecules serve as versatile synthetic building blocks. Here, we report an iron(II)/cobalt(II) dual catalytic system for the syntheses of distally unsaturated amide derivatives. The transformation proceeds through iron nitrenoid-mediated 1,5-hydrogen atom transfer (1,5-HAT) mechanism. Subsequently, radical intermediate undergoes hydrogen abstraction from vicinal methylene by a cobaloxime catalyst, efficiently yielding β,γ- or γ,δ-unsaturated derivatives under mild conditions. efficiency Co-mediated HAT can be tuned varying different auxiliaries, highlighting generality this protocol. Remarkably, desaturation protocol is also amenable to practical scalability, enabling synthesis carbamates ureas, which readily converted into various valuable molecules.

Язык: Английский

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Synthesis of non-canonical amino acids through dehydrogenative tailoring

Nature, Год журнала: 2024, Номер 634(8033), С. 352 - 358

Опубликована: Авг. 29, 2024

Язык: Английский

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Directed Photochemically Mediated Nickel-Catalyzed (Hetero)arylation of Aliphatic C–H Bonds

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(7), С. 3882 - 3890

Опубликована: Фев. 13, 2023

Site-selective functionalization of unactivated C(sp3)–H centers is challenging because the ubiquity and strength alkyl C–H bonds. Herein, we disclose a position-selective C(sp3)–C(sp2) cross-coupling reaction. This process engages bonds aryl bromides, utilizing catalytic quantities photoredox-capable molecule nickel precatalyst. Using this technology, selective arises owing to 1,6-hydrogen atom transfer (HAT) that guided by pendant alcohol-anchored sulfamate ester. These transformations proceed directly from N–H bonds, in contrast previous directed, radical-mediated, arylation processes, which have relied on prior oxidation reactive nitrogen center reactions with nucleophilic arenes. Moreover, these conditions promote at secondary good yields excellent selectivity.

Язык: Английский

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Oxidations of Alcohols, Aldehydes, and Diols Using NaBr and Selectfluor

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(15), С. 11240 - 11252

Опубликована: Июль 25, 2023

We present protocols for the oxidation of alcohols and aldehydes oxidative cyclization diols which use a combination Selectfluor NaBr. For most substrates, optimal solvent system is 1:1 mixture CH3CN/H2O, but, in select cases, biphasic mixtures EtOAc/H2O or CH2Cl2/H2O are superior. This procedure operationally simple, uses inexpensive readily available reagents, tolerates variety functional groups. Mechanistic studies suggest that active oxidant hypobromous acid, generated by almost instantaneous Br– an aqueous milieu.

Язык: Английский

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Nitrogenation and Oxygenation of an Unstrained C–C Bond Enabled by the Merger of Visible-Light and Cu-Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(4), С. 2402 - 2408

Опубликована: Янв. 31, 2024

Unstrained carbon–carbon bonds are among the most prevalent and inert chemical bonds. Thus, developing synthetic transformations directly from unstrained under mild conditions is ideal yet challenging due to inertness steric hindrance. Here, a visible-light copper-catalyzed azidation etherification of remote C–C bond amines via 1,4-aryl migration have been reported. This redox-neutral protocol shows exquisite site-selectivity, broad scope, good functional group tolerance, transforming C–N C–O at room temperature. Facile derivatizations benzyl azide products into free amines, triazoles, phosphamides highlight potential utility this method for target molecule synthesis medicinal chemistry.

Язык: Английский

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γ-Amino C(sp³)–H Functionalization of Aliphatic Amines through a Light-Driven Triple Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(10), С. 8005 - 8012

Опубликована: Май 9, 2024

We report intra- and intermolecular γ-amino C(sp3)–H functionalization of aliphatic amines using a vinylsulfone-based HAT (hydrogen atom transfer) auxiliary triple catalysis, which is composed photoredox, cobalt, Brønsted acid catalysts under visible light irradiation. The process accomplishes four elementary steps: (i) electrophilic carbon-centered radical formation on the via MHAT (metal hydride hydrogen reaction, (ii) generation through 1,6-HAT (iii) single-electron oxidation to carbocation equivalents, (iv) nucleophilic substitution with internal or external nucleophiles. As result, this afforded γ-amino-functionalized products, such as azetidines, 1,3-diamine, 1,3-aminoalcohol derivatives.

Язык: Английский

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Modifying commodity-relevant unsaturated polymers via Co-catalyzed MHAT

Chem, Год журнала: 2024, Номер 10(10), С. 3088 - 3099

Опубликована: Июнь 19, 2024

Язык: Английский

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