Photochemical Alkylamination of Olefins through Reactivity-Based Sorting of Alkyl Radicals

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

Published: March 3, 2025

Alkyl radicals represent some of the most intriguing prospects in organic synthesis, showing diverse patterns reactivity for versatile transformations. In light this, methyl radical, addition to being a methylating agent, is also good proposition hydrogen atom transfer (HAT). Similarly, acetonitrile has dual facets its reactivity, acting as an amination reagent Ritter reaction while progenitor cyanomethyl through HAT. We hereby take advantage merging reactivities these radicals, allowing facile access amines various types from olefins when conjugated with photoredox amination.

Language: Английский

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Synergistic LMCT and Ni Catalysis for Methylative Cross-Coupling Using tert-Butanol: Modulating Radical Pathways via Selective Bond Homolysis

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 18, 2025

Ligand-to-metal charge transfer (LMCT) excitation has emerged as a potent strategy for the selective generation of heteroatom-centered radicals, yet its full potential in modulating open-shell radical pathways remains underexplored. Here, we present photocatalytic methylative cross-coupling reaction that capitalizes on synergistic interplay between LMCT and Ni catalysis, enabling use tert-butanol an efficient benign methylating reagent. The electron-deficient ligand 2,6-ditrifluoromethyl benzoate facilitates Ce(IV)-mediated bond scission tert-butanol, generating methyl is subsequently captured by catalytic cycle to form C-CH3 bonds. Under mild conditions, this affords methylation sp3 carbons adjacent carbonyls sp2 centers, demonstrating broad functional group tolerance applicability late-stage functionalization bioactive molecules. Additionally, trideuteromethylative coupling can be facilely achieved using commercial tert-butanol-d10. This approach circumvents need traditional tert-butoxy precursors, such peroxides, while strategically pathway favor β-scission suppress unwanted formation solution. Mechanistic studies reveal plays crucial role facilitating generation, supporting concerted Ce-OR β-C-C homolysis mechanism, further evidenced modulation regioselectivity alkoxy radical-mediated β-scission.

Language: Английский

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Pnictogen and Chalcogen Salts as Alkylating Agents

The Chemical Record, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 16, 2024

Abstract Alkylation reactions and their products are considered crucial in various contexts. Synthetically, the alkylation of a nucleophile is usually promoted using hazardous alkyl halides. Here, we aim to highlight potential pnictogen (ammonium or phosphonium) chalcogen salts (sulfonium, selenonium, telluronium) function as alkylating agents. These compounds can be non‐volatile electrophilic reservoirs. We will center our discussion on strategies developed recent years expand synthetic utility these terms transferable groups, substrate scope, product selectivity.

Language: Английский

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I₂-Mediated [3 + 3] Annulation for the Construction of Indole-Pyrimidine-Pyrazole-Fused Tetracyclic Heteroarenes

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(20), P. 15164 - 15169

Published: Oct. 7, 2024

An I2-mediated annulation of 3-aminopyrazoles with indole-3-carboxaldehydes has been demonstrated for the first time. This tandem strategy allows facile construction indole-pyrimidine-pyrazole-fused tetracyclic heteroarenes that are otherwise inaccessible by existing methods. These fused heterocycles exhibited enhanced antifungal activities against Valsa mali and Botryosphaeria dothidea compared commercial Xemium fungicide.

Language: Английский

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