Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(9), P. 6078 - 6144

Published: April 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Language: Английский

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Mechanisms of Photoredox Catalysis Featuring Nickel–Bipyridine Complexes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(11), P. 9055 - 9076

Published: May 29, 2024

Metallaphotoredox catalysis can unlock useful pathways for transforming organic reactants into desirable products, largely due to the conversion of photon energy chemical potential drive redox and bond transformation processes. Despite importance these processes cross-coupling reactions other transformations, their mechanistic details are only superficially understood. In this review, we have provided a detailed summary various photoredox mechanisms that been proposed date Ni-bipyridine (bpy) complexes, focusing separately on photosensitized direct excitation reaction By highlighting multiple key findings, depict how mechanisms, which ultimately define substrate scope, themselves defined by ground- excited-state geometric electronic structures Ni-based intermediates. We further identify knowledge gaps motivate future studies development synergistic research approaches spanning physical, organic, inorganic chemistry communities.

Language: Английский

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Ni‐Catalyzed Photochemical C−N Coupling of Amides with (Hetero)aryl Chlorides

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(37)

Published: April 17, 2023

This paper reports a photochemical C-N coupling of abundant, but less reactive aryl chlorides, with structurally diverse primary and secondary amides by Ni-mediated without an external photocatalyst. Under the irradiation light (390-395 nm) soluble organic amine as base, reaction allows for successful transformation (hetero)aryl chlorides to wide range N-aryl amides. More than 60 examples are shown, demonstrating feasibility applicability this protocol in synthesis. Mechanic studies indicate that amidation proceeds via Ni(I)-Ni(III) catalytic cycle.

Language: Английский

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Unleashing the potentiality of metals: synergistic catalysis with light and electricity

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(14), P. 4024 - 4040

Published: Jan. 1, 2024

This review provides a comprehensive overview of metal catalysis in photo-electrochemical systems, discussing reaction mechanisms and offering prospects for this triadic catalytic mode.

Language: Английский

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Photogenerated Ni(I)–Bipyridine Halide Complexes: Structure–Function Relationships for Competitive C(sp²)–Cl Oxidative Addition and Dimerization Reactivity Pathways

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(24), P. 9538 - 9551

Published: June 6, 2023

We report the facile photochemical generation of a library Ni(I)-bpy halide complexes (Ni(I)(Rbpy)X (R = t-Bu, H, MeOOC; X Cl, Br, I) and benchmark their relative reactivity toward competitive oxidative addition off-cycle dimerization pathways. Structure-function relationships between ligand set are developed, with particular emphasis on rationalizing previously uncharacterized ligand-controlled high energy challenging C(sp2)-Cl bonds. Through dual Hammett computational analysis, mechanism formal is found to proceed through an SNAr-type pathway, consisting nucleophilic two-electron transfer Ni(I) 3d(z2) orbital Caryl-Cl σ* orbital, which contrasts observed for activation weaker C(sp2)-Br/I The bpy substituent provides strong influence reactivity, ultimately determining whether or even occurs. Here, we elucidate origin this as arising from perturbations effective nuclear charge (Zeff) center. Electron donation metal decreases Zeff, leads significant destabilization entire 3d manifold. Decreasing electron binding energies powerful donor activate These changes also prove have analogous effect dimerization, in Zeff leading more rapid dimerization. Ligand-induced modulation thus tunable target by can be altered, providing direct route stimulate stronger C-X bonds potentially unveiling new ways accomplish Ni-mediated photocatalytic cycles.

Language: Английский

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Light-Promoted Nickel-Catalyzed C–O/C–N Coupling of Aryl Halides with Carboxylic Acids and Sulfonamides

Organic Letters, Journal Year: 2023, Volume and Issue: 25(4), P. 636 - 641

Published: Jan. 20, 2023

A general strategy for the construction of dual-functional carbon-heteroatom bonds has been developed via a light-promoted nickel catalytic system. Employing simple NiBr2 as catalyst without any exogeneous ligands and photosensitizers, variety esters sulfonamide N-arylation derivatives, including celecoxib- glimepiride-derived sulfonamides, were readily accessed with high functional group tolerance efficiency. Moreover, UV-vis absorption spectrum free radical trapping experiments aimed at revealing mechanism reaction are also presented.

Language: Английский

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Gold-Catalyzed C–O Cross-Coupling Reactions of Aryl Iodides with Silver Carboxylates

Organic Letters, Journal Year: 2023, Volume and Issue: 25(34), P. 6334 - 6339

Published: Aug. 21, 2023

We have developed a C-O cross-coupling reaction of (hetero)aryl iodides with silver carboxylates via AuI/AuIII catalytic cycle. The transformation featured exclusive chemoselectivity and moisture/air insensitivity. Aromatic aliphatic (including primary, secondary, tertiary) are all suitable substrates. Moreover, this protocol worked well intermolecularly intramolecularly. Most importantly, good yields were obtained regardless the substrates' electronic effect steric hindrance.

Language: Английский

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Werner Salt as Nickel and Ammonia Source for Photochemical Synthesis of Primary Aryl Amines

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(6)

Published: Nov. 2, 2023

Cheap, stable and easy-to-handle Werner ammine salts have been known for more than a century; but they rarely used in organic synthesis. Herein, we report that the hexammine complex [Ni(NH

Language: Английский

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Visible light-induced radical cyclization of o-alkenyl aromatic isocyanides with thioethers: direct synthesis of 2-thioquinolines

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(7), P. 2033 - 2039

Published: Jan. 1, 2024

A novel visible-light-induced regioselective radical cyclization reaction of isocyanides with thioethers has been developed. This provides an efficient method for the construction highly functionalized quinolines in a single step.

Language: Английский

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Excited-State Nickel-Catalyzed Amination of Aryl Bromides: Synthesis of Diphenylamines and Primary Anilines

Organic Letters, Journal Year: 2024, Volume and Issue: 26(8), P. 1657 - 1661

Published: Feb. 21, 2024

Excited-state nickel-catalyzed C–N cross-coupling of aryl bromides with sodium azide enables the synthesis diarylamines and primary anilines under mild reaction conditions. The oxidative addition electron-rich low-valent Ni photochemical conditions is endothermic. Herein, we demonstrate a light-mediated electronically rich that yields diarylamines, while electron-deficient gives access to at room temperature.

Language: Английский

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