Nickel-Catalyzed Cross-Electrophile Coupling of Aryl Triflates with Alkyl Halides: Mechanism-Informed Design of More General Conditions

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

Published: Jan. 10, 2025

Aryl triflates make up a class of aryl electrophiles that are available in single step from the corresponding phenol. Despite known reactivity nickel complexes for C-O bond activation phenol derivatives, nickel-catalyzed cross-electrophile coupling using has proven challenging. Herein, we report method to form C(sp2)-C(sp3) bonds by with alkyl bromides and chlorides phenanthroline (phen) or pyridine-2,6-bis(N-cyanocarboxamidine) (PyBCamCN)-ligated catalysts. The scope reaction is demonstrated 38 examples (61 ± 14% average yield). Mechanistic studies provide rationale conditions used roadmap further applications coupling. First, rate radical generation controlled maintaining majority halide as chloride, which unreactive, utilizing dynamic exchange process adjust concentration reactive bromide iodide. Second, challenge electron-rich appears be due off-cycle transmetalation unproductive zinc reagents. optimal PyBCamCN ligand together LiCl avoids this deleterious step.

Language: Английский

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One-Pot Chlorination and Cross-Electrophile Coupling of Alcohols with Aryl Chlorides

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

Published: Jan. 24, 2025

Although alkyl alcohols and aryl chlorides are the two most abundant substrate pools for cross-electrophile coupling, methods to couple them remain limited. Herein we demonstrate a simple procedure in situ deoxychlorination of followed by XEC with chlorides. A broad scope can be achieved tuning rate reaction via halide exchange. Key success is identification 1-chloro-N,N,2-trimethyl-1-propenylamine as mild, noninterfering halogenation reagent.

Language: Английский

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Electrochemical Nickel-Catalyzed C(sp²)-H Functionalization of Tropones with Aldehydes

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 3184 - 3190

Published: Feb. 6, 2025

A direct electroreductive functionalization of tropones employing aldehydes as alkylating agents is reported. This C(sp2)-H process leverages the mediation electroactive nickel complexes, enabling a wide range both native and substituted (44 examples) to be alkylated selectively at α-position in high yields (up 90%). Combined electrochemical, spectroelectrochemical, computational analyses disclosed whole mechanistic pathway revealed key role played by reduced Ni complexes activating tropone core toward condensation with aldehydes.

Language: Английский

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Zn-promoted Sandmeyer-type reductive chalcogenation of (hetero)aryl diazonium salts

Organic Chemistry Frontiers, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

In this report, we describe a nickel-free, zinc-induced reductive coupling between (hetero)aryl diazonium salts and electrophilic chalcogen species under mild reaction conditions.

Language: Английский

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New reactivity of late 3d transition metal complexes in catalytic reactions of alkynes

Chemical Society Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This review summarizes seven types of new reactivities found in late 3d metal complexes and catalytic examples recent years.

Language: Английский

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Cross-Electrophile Coupling to Form Sterically Hindered C(sp²)–C(sp³) Bonds: Ni and Co Afford Complementary Reactivity

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

Published: March 7, 2025

The formation of sterically hindered C(sp2)-C(sp3) bonds could be a useful synthetic tool but has been understudied in cross-electrophile coupling. Here, we report two methods that couple secondary alkyl bromides with aryl halides contain C-X bonds: 1) ortho-substituted nickel catalysts and 2) di-ortho-substituted iodides cobalt catalysts. Stoichiometric experiments deuterium labeling studies show [Co] is better than [Ni] for oxidative addition Ar-I radical capture/reductive elimination steps arenes. For both metals, Ar-H side products observed reactions low-yielding appear to arise from Ar• hydrogen-atom transfer the solvent. While origins differences scope are not yet understood, these demonstrate previously unknown complementarity between

Language: Английский

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Nickel‐Catalyzed LiCl‐Controlled Switchable Carboxylation of Aryl C—F Bonds with One or Two Molecules of CO₂

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Comprehensive Summary The use of CO 2 as a renewable C1 source for the synthesis value‐added chemicals can contribute to more sustainable chemistry. In this work, nickel‐catalyzed amide‐directed carboxylation aryl C−F bonds with has been developed. reaction is switchable controlled by LiCl react one or two molecules afford valuable phthalimides α‐hydroxycarboxylic acid derivatives. Further study shows that step‐by‐step process. first step and tandem cyclization phthalimides. second C−N bond , intramolecular nucleophilic addition amide anion carbonyl. also developed based on reaction. work features inert functionalization, activation, multiple incorporation. Mechanistic studies indicate azanickelacycle intermediates play an important role, facilitates reduction Ni(II) Ni(I) promotes molecule . This protocol provides efficient route functionalization under mild conditions via chemical fixation

Language: Английский

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Cross-Electrophile Coupling of Aryl Chlorides with Alkyl Chlorides Using Rotating Magnetic Field and Metal Rods

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

Published: April 1, 2025

The pursuit of sustainable and environmentally benign methods techniques continues to challenge organic chemists. Herein, we report the development a novel approach in which electromagnetic induction could participate coupling chlorides using rotating magnetic field metal rods. In particular, describe application this strategy nickel-catalyzed cross-electrophile aryl with alkyl chlorides. Using these abundant commercially available organochlorides, such system allows reactions proceed broader scope than current protocols under mild conditions.

Language: Английский

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Translation of Nickel-Catalyzed C(sp²)–C(sp³) Cross-Electrophile Coupling to Non-Amide Solvents

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

Published: April 14, 2025

The cross-electrophile coupling of organobromides is widely utilized in organic synthesis but generally requires undesirable amide solvents (e.g., DMF, DMA, and NMP). We report that the combination a strongly donating, bidentate nitrogen ligand, LiI, 4-picoline enables variety alcohol, ester, ethereal at up to 50 g scale. An improved optimal 4,4'-bis(dimethylamino)-2,2'-bipyridine, also reported on basis reductive homocoupling 4-dimethylamino-2-chloropyridine.

Language: Английский

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Non-Innocent Role of Sacrificial Anodes in Electrochemical Nickel-Catalyzed C(sp²)–C(sp³) Cross-Electrophile Coupling

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(47), P. 32249 - 32254

Published: Nov. 15, 2024

Sacrificial anodes composed of inexpensive metals such as Zn, Fe, and Mg are widely used to support electrochemical nickel-catalyzed cross-electrophile coupling (XEC) reactions, in addition other reductive transformations. Such appealing because they provide a stable counter-electrode potential typically avoid interference with the chemistry. The present study outlines development an Ni-catalyzed XEC reaction that streamlines access key pharmaceutical intermediate. Metal ions derived from sacrificial anode oxidation, however, directly contribute homocoupling proto-dehalogenation side products commonly formed chemical reactions. Use divided cell limits by anode-derived metal supports high product yield negligible formation, introducing strategy overcome one main limitations XEC.

Language: Английский

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