Allylgermane synthesis via facile and general nickela-electrocatalyzed electrophile coupling

Chem Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 101257 - 101257

Published: Feb. 1, 2025

Language: Английский

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Cobalt‐Catalyzed Photo‐Semipinacol Rearrangement of Unactivated Allylic Alcohols

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(35)

Published: June 7, 2024

We report a photochemical method for the semipinacol rearrangement of unactivated allylic alcohols. Aliphatic as well aromatic groups participate migrating groups, yielding variety α,α-disubstituted ketones. The reaction proceeds under mild conditions and is compatible with ethers, esters, halides, nitriles, carbamates, substituted arenes. operationally simple fully catalytic prescribe 1 mol % benzothiazinoquinoxaline organophotocatalyst, 0.5 Co-salen, 10 lutidinium triflate and, importantly, display reactivity complementary to procedures employing Brønsted acid. showcase utility protocol in late-stage drug diversifications.

Language: Английский

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

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(10), P. 8005 - 8012

Published: May 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.

Language: Английский

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Cobalt Hydride-Catalyzed Hydroalkynylation of Alkenes with Alkynyl Trifluoroborates

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(12), P. 9294 - 9301

Published: June 4, 2024

A cobalt-catalyzed hydroalkynylation of alkenes with alkynyl trifluoroborates is described, proceeding through a cobalt hydride-mediated radical-polar crossover metal hydrogen-atom-transfer process. This method affords structurally diverse alkynyl-containing compounds in high yields under mild conditions and features wide substrate scope, good functional group tolerance, suitability for late-stage functionalization relatively complex natural products bioactive molecules. Expanding the scope to alkenyltrifluoroborate salts further increases utility developed methodology. approach paves an alternative route radical-involved alkynylation alkenylation reactions nucleophilic alkynyl/alkenyl reagents.

Language: Английский

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Photo- and Cobalt-Catalyzed Cycloisomerization of Unsaturated Guanidines, (Iso-)Ureas, and Carbonates

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

We report intramolecular photocatalyzed cycloisomerization of unactivated olefins with pendant nucleophiles. The reaction proceeds under mild conditions and utilizes guanidines, ureas, isoureas, isothioureas, carbonates to yield several different five-, six-, seven-membered heterocycles. Use benzothiazinoquinoxaline as an organophotocatalyst cobalt–salen catalyst obviates the need for a stoichiometric oxidant or reductant.

Language: Английский

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Electrochemical Ring Opening and [3 + 2] Cycloaddition of Aziridines: Access to 1,2-Bifunctionalized Products and Imidazolines

Organic Letters, Journal Year: 2025, Volume and Issue: 27(4), P. 989 - 994

Published: Jan. 21, 2025

Herein, we report an electricity-driven activation of aziridine via direct anodic oxidation to give N-heterocycles and 1,2-bifunctionalized products by excluding any oxidant/reductant or metal catalyst. Many structurally modified aziridines were employed in the presence different nitriles. A large variety nucleophiles screened furnish chemoselectively O-alkylated C-alkylated products. Late-stage derivatization with natural medicinally active compounds has also been done. Remarkably, our strategy was found be a greener, sustainable, atom-economical approach (E-factor = ca. 0.8). Azetidine compatible protocol generated six-membered N-heterocycles. The detailed mechanistic study highlighted that reaction is driven generation radical cation followed SN2 nucleophilic attack.

Language: Английский

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Regioselective 1,4-Hydroamination of 1,3-Dienes by Photoredox/Cobalt Dual Catalysis

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

Herein, we report a visible-light-driven and cobalt-mediated 1,4-hydroamination reaction of 1,3-dienes with arylmines as the nucleophiles. The involves regioselective addition [CoIII]–H to 1,3-diene, followed by oxidation nucleophilic substitution amines. Using Ir(ppy)3 photocatalyst enables cobalt redox cycle be implemented without using an external oxidant hydride regent. This protocol can applied well forge carbon–oxygen carbon–sulfur bonds in analogous way.

Language: Английский

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A Photo- and Cobalt-Catalyzed Highly Selective and Divergent Hydrofunctionalization of 1,3-Dienes with Phenols

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

An applicable cobalt-hydride-mediated selective, divergent hydroetherification and sequential hydroetherification/hydroarylation of 1,3-dienes with simple phenol feedstocks under a photoredox cobalt catalytic system have been developed. A variety allyl aryl ethers value-added chroman derivatives can be obtained in good to excellent yields stereoselectivity. This method not only obviates the need for extra hydrosilanes stoichiometric oxidants, thereby offering exceedingly mild conditions alkene hydroetherification, but also represents first case CoH-HAT-catalyzed double hydrofunctionalization alkenes sole nucleophile. The continuous selective bond-forming expands applications cobalt-hydride MHAT reaction provides novel approach design synthesis heterocyclic molecules.

Language: Английский

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Photoredox and Cobalt-Catalyzed Markovnikov-Selective Radical Hydroamination of Unactivated Alkenes with Anilines

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 26, 2025

The intermolecular hydroamination of unactivated alkenes with simple amines continues to be an attractive and challenging undertaking in organic synthesis. current state-of-the-art strategies for photocatalyzed usually commence the formation a C–N bond, thereby delivering exclusively anti-Markovnikov products. We herein reported facile mild Markovnikov anilines through photoredox cobalt-catalyzed hydrogen atom transfer followed by radical-polar crossover nucleophilic amination process. reaction features wide substrate scope, good functional group tolerance, excellent yields. Application this late-stage functionalization relatively complex natural products bioactive molecules further increases utility developed methodology.

Language: Английский

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The selective adsorption mechanism of an amino acid surfactant in the flotation separation of fluorite from calcite

Chemical Engineering Science, Journal Year: 2025, Volume and Issue: unknown, P. 121617 - 121617

Published: April 1, 2025

Language: Английский

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