Aryne Chemistry: Generation Methods and Reactions Incorporating Multiple Arynes

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(20), P. 11435 - 11522

Published: Oct. 9, 2024

Arynes hold significance for the efficient fusion of (hetero) arenes with diverse substrates, advancing construction complex molecular frameworks. Employing multiple equivalents arynes is particularly effective in rapid formation polycyclic cores found optoelectronic materials and bioactive compounds. However, inherent reactivity often leads to side reactions, yielding unanticipated products underlining importance a detailed investigation into use fine-tune their reactivity. This review centers on methodologies syntheses organic reactions involving arynes, categorizing based mechanisms like cycloadditions, σ-bond insertions, nucleophilic additions, ene discusses aryne polymerization. The categorization these includes two primary approaches: first entails engagement within single step while second approach involves using equivalent sequentially across steps, both requiring strict control ensure precise participation each respective step. Additionally, provides an in-depth analysis selection precursors, organized chronologically by activation strategy, offering comprehensive background that supports main theme utilization. expectation remains this will be invaluable designing advanced engaging arynes.

Language: Английский

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A Unified Method for Oxidative and Reductive Decarboxylative Arylation with Orange Light-Driven Ir/Ni Metallaphotoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(37), P. 25780 - 25787

Published: Sept. 5, 2024

Carboxylic acids and their derivatives are powerful building blocks in dual Ir/Ni metallaphotoredox methods of decarboxylative arylation due to abundance as feedstock compounds. However, the library accessible carboxylic is limited by trends radical stability, often necessitating development specific systems for challenging substrates. Herein, we disclose application a new Ir(III) photocatalyst low-energy orange light system with broad applicability activating both native redox-active esters (RAEs). This method represents first known example complementary oxidative reductive paradigms broadly similar reaction conditions, unlocking reactivity We further show wide scope aryl halide acid coupling partners regimes, added advantages over blue-light-catalyzed alkylation photosensitive

Language: Английский

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Pd-Catalyzed C–O Bond Formation: Coupling of Aryl Boronic Acids with O-Electrophiles

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 3636 - 3646

Published: Feb. 14, 2025

Language: Английский

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Phenothiazine Sulfoxides as Active Photocatalysts for the Synthesis of γ-Lactones

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

Published: April 2, 2025

N-substituted phenothiazines are prominent and highly effective organic photoredox catalysts, particularly known for their strong reducing capabilities. Despite wide utility, the closely related phenothiazine sulfoxides, which easily form upon oxidation, have been largely overlooked not explored in context of photocatalysis. Herein, we describe discovery application N-phenylphenothiazine sulfoxide as a photocatalyst reductive activation cyclic malonyl peroxides, giving access to complex γ-lactones starting from simple olefins. Detailed mechanistic studies were carried out better understand situ formation active catalyst species commercial precursor, well interconversion photocatalytic mechanism γ-lactone products. Specifically, employed broad range tools, including time-resolved spectroscopy, spectroelectrochemistry, transient UV-vis absorption voltammetry, isotopic labeling, radical trapping experiments, NMR density functional theory (DFT) calculations. The synthetic utility this protocol is demonstrated substrate scope study, highlighting facile spirocyclic γ-lactones, widely recognized biological importance.

Language: Английский

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Ligand‐Controlled Copper‐Catalyzed Halo‐Halodifluoromethylation of Alkenes and Alkynes Using Fluorinated Carboxylic Anhydrides

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: July 9, 2024

Polyhalogenated molecules are often found as bioactive compounds in nature and used synthetic building blocks. Fluoroalkyl hold promise for the development of novel pharmaceuticals agrochemicals, introduction fluoroalkyl groups is known to improve lipophilicity, membrane permeability, metabolic stability. Three-component 1,2-halo-halodifluoromethylation reactions alkenes useful their synthesis. However, general methods enabling halodifluoromethyl (CF

Language: Английский

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t-BuOOH/TiO2 Photocatalytic System as a Convenient Peroxyl Radical Source at Room Temperature under Visible Light and Its Application for the CH-Peroxidation of Barbituric Acids

Catalysts, Journal Year: 2023, Volume and Issue: 13(9), P. 1306 - 1306

Published: Sept. 19, 2023

TiO2 is one of the most promising heterogeneous photoredox catalysts employed in oxidative pollutant destruction, CO2 reduction, water splitting, disinfection, solar cell design and organic synthesis. Due to wide bandgap TiO2, visible light energy not sufficient for its activation, electron/hole pairs generated upon UV irradiation demonstrate limited selectivity application Thus, development TiO2-based catalytic systems activated by highly attractive. In present work we generation t-BuOO• radicals from tert-butylhydroperoxide catalyzed using commercially available unmodified under light. This finding was used selective CH-peroxidation barbituric acids, which contrasts with behavior known TiO2/H2O2/UV photocatalytic system deep oxidation pollutants.

Language: Английский

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Macrocyclic Organic Peroxides: Constructing Medium and Large Cycles with O-O Bonds

Chemistry, Journal Year: 2024, Volume and Issue: 6(5), P. 1246 - 1270

Published: Oct. 15, 2024

Macrocycles bridge the gap between conventional small molecules and polymers. Drawing inspiration from successful carbon heteroatom-containing macrocycles, peroxide-containing macrocycles are gaining attention for enhanced bioactivity, potential chelating properties, applications in energetic materials. This review presents following strategies construction of cyclic peroxides with 10- to 36-membered frameworks: (1) intramolecular iodocyclization hydroperoxides, (2) intermolecular cyclization hydroperoxides alkyl dihalides or carbonyls, (3) acid-catalyzed rearrangements ozonides 11-membered triperoxides via oxy- peroxycarbenium ions, (4) peroxidation carbonyls targeting macrocyclic peroxides. The specific agents that allow selective medium large cycles also analyzed.

Language: Английский

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FeCl₂-Mediated Rearrangement of Aminoperoxides into Functionalized Tetrahydrofurans: Dynamic Non-innocence of O-Ligands at an Fe Center Coordinates a Radical Cascade

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 27, 2024

The selective reaction of cyclic aminoperoxides with FeCl2 proceeds through a sequence O–O and C–C bond cleavages, followed by intramolecular cyclization, yielding functionalized tetrahydrofurans in 44–82% yields. Replacing the peroxyacetal group peroxide structure peroxyaminal fragment fundamentally alters pathway. Instead producing linear ketones, this modification leads to formation hard-to-access substituted tetrahydrofurans. Although aminoperoxide cores undergo multiple scissions, cascade is atom-economical. Computational analysis shows that O-ligands at Fe center have enough radical character promote fragmentation subsequent cyclization. stereoelectronic flexibility oxygen, combined iron's capacity stabilize reactive intermediates during multistep cascade, explains efficiency new atom-economic rearrangement.

Language: Английский

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Bioinspired Fe(II)‐Mediated Halogenative C−C Bond Activation of Ozonides: Temporary Installment of a Peroxide Bridge Allows Selective C−C Scissions for Replacement of a Carbonyl Group by a Halogen

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(23), P. 4190 - 4197

Published: Oct. 17, 2023

Abstract A selective reaction of bridged ozonides with Fe(II) salts proceeds through the sequence O−O, C−C scissions and halogenation to form α‐halogen substituted δ‐ketoesters δ‐diketones in 15–72% yields. The overall shows how a temporary installation peroxide functionality can be used replace acyl group within an acetoacetic ester unit halogen.

Language: Английский

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An Unusual Rearrangement of Pyrazole Nitrene and Coarctate Ring-Opening/Recyclization Cascade: Formal CH–Acetoxylation and Azide/Amine Conversion without External Oxidants and Reductants

Molecules, Journal Year: 2023, Volume and Issue: 28(21), P. 7335 - 7335

Published: Oct. 30, 2023

We report an unusual transformation where the transient formation of a nitrene moiety initiates sequence steps leading to remote oxidative C-H functionalization (R-CH3 R-CH2OC(O)R') and concomitant reduction into amino group. No external oxidants or reductants are needed for this formal molecular comproportionation. Detected isolated intermediates computational analysis suggest that process occurs with pyrazole ring opening recyclization.

Language: Английский

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