Photochemical dearomative skeletal modifications of heteroaromatics

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(12), P. 6600 - 6624

Published: Jan. 1, 2024

Dearomatization has emerged as a powerful tool for rapid construction of 3D molecular architectures from simple, abundant, and planar (hetero)arenes. The field evolved beyond simple dearomatization driven by new synthetic technology development. With the renaissance photocatalysis expansion activation mode, last few years have witnessed impressive developments in innovative photochemical methodologies, enabling skeletal modifications dearomatized structures. They offer truly efficient useful tools facile highly complex structures, which are viable natural product synthesis drug discovery. In this review, we aim to provide mechanistically insightful overview on these innovations based degree alteration, categorized into dearomative functionalization editing, highlight their utilities.

Language: Английский

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Decatungstate‐Photocatalyzed Diastereoselective Dearomative Hydroalkylation of Indoles

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(22)

Published: April 16, 2024

Abstract In this study, we present an efficient and straightforward dearomative hydroalkylation of indoles. By utilizing alkanes or ethers as alkyl radical sources employing TBADT a cost‐effective photocatalyst for direct hydrogen atom transfers (HAT), achieved successful conversion these heterocyclic derivatives into 2‐alkylindolines with good to excellent yields high diastereoselectivity under mild reaction conditions.

Language: Английский

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Photoredox-catalyzed diastereoselective dearomative prenylation and reverse-prenylation of electron-deficient indole derivatives

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 30, 2023

Abstract Prenylated and reverse-prenylated indolines are privileged scaffolds in numerous naturally occurring indole alkaloids with a broad spectrum of important biological properties. Development straightforward stereoselective methods to enable the synthesis structurally diverse prenylated indoline derivatives is highly desirable challenging. In this context, most direct approaches achieve goal generally rely on transition-metal-catalyzed dearomative allylic alkylation electron-rich indoles. However, electron-deficient indoles much less explored, probably due their diminished nucleophilicity. Herein, photoredox-catalyzed tandem Giese radical addition/Ireland–Claisen rearrangement disclosed. Diastereoselective prenylation reverse-prenylation proceed smoothly under mild conditions. An array tertiary α-silylamines as precursors readily incorporated 2,3-disubstituted high functional compatibility excellent diastereoselectivity (>20:1 d.r.). The corresponding transformations secondary provide biologically lactam-fused one-pot synthesis. Subsequently, plausible photoredox pathway proposed based control experiments. preliminary bioactivity study reveals potential anticancer property these appealing indolines.

Language: Английский

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A Visible-Light-Induced α-Aminoalkyl-Radical-Mediated Halogen-Atom Transfer Process: Modular Synthesis of Phenanthridinone Alkaloids

Organic Letters, Journal Year: 2023, Volume and Issue: 25(10), P. 1689 - 1694

Published: March 3, 2023

A halogen-atom transfer (XAT) strategy utilizing α-aminoalkyl radicals allows the generation of aryl at room temperature, which is applied for intramolecular cyclization reactions en route to biologically relevant alkaloids. Starting from simple halogen-substituted benzamides under visible light irradiation in presence an organophotocatalyst (4CzIPN) and nBu3N modular construction phenanthridinone core, gives facile access drug analogs alkaloids, e.g., Amaryllidaceae family. The reaction pathway most likely involves a quantum mechanical tunneling enabled event achieve aromatization-halogen-atom transfer.

Language: Английский

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Recent advances in visible light mediated photoinduced aryl radical generation and its application in synthesis

Journal of Photochemistry and Photobiology, Journal Year: 2023, Volume and Issue: 16, P. 100192 - 100192

Published: June 16, 2023

The reactions involving aryl radicals is an efficient strategy for the synthesis of a wide variety important molecules. We have highlighted here recent developments on generation from various substrates by visible light mediated photocatalysis and their with different to produce library arylated het-arylated compounds. These are performed at room temperature using LED bulbs. Thus, this green less energy.

Language: Английский

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From benzopyrroles to phenylpyrroles: remodeling of indoles enabled by photoredox catalysis

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(15), P. 3875 - 3882

Published: Jan. 1, 2023

A photocatalyzed facile remodeling of indoles to o -aminobiaryls under mild conditions was achieved.

Language: Английский

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Photoacid-Catalyzed Esterification of Carboxylic Acids Using Eosin Y

Organic Letters, Journal Year: 2025, Volume and Issue: 27(4), P. 1018 - 1023

Published: Jan. 21, 2025

A photoacid-catalyzed method for esterification is proposed wherein eosin Y introduced as a photoacid and photoredox catalyst that can be activated with visible light catalyze the of carboxylic acids. The strategy presented here revealed proton-coupled electron transfer (PCET) between acid might facilitate formation transient ketyl radical. This radical would subsequently undergo single then couple alkyl alcohols, yielding esters in good to excellent yields.

Language: Английский

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Nickel-Catalyzed Electroreductive Heck Reaction: A Divergent Synthesis of C7- or C2-Arylindolines

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

Published: April 9, 2025

Herein, we present a novel electrochemically driven nickel-catalyzed Heck reaction of readily available N-arylacrylindoles for the construction both 7-arylindolines and 2-arylindolines. The proceeds in an undivided electrochemical cell employs sacrificial zinc anode as reductant. This catalytic protocol features consecutive electroreductive process under exceedingly mild conditions, with moderate yields. Detailed mechanistic studies indicate that involves domino sequence intramolecular arylation selective C-C or C-O bond cleavage, which could be accomplished by aryl migration carbethoxy removal.

Language: Английский

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Synthesis of Pyrroloindolines via N-Heterocyclic Carbene Catalyzed Dearomative Amidoacylation of Indole Derivatives

Organic Letters, Journal Year: 2023, Volume and Issue: 25(48), P. 8677 - 8682

Published: Nov. 23, 2023

Pyrroloindoline is a privileged heterocyclic motif that widely present in many natural products and pharmaceutical compounds. Herein, we report an amidyl radical-mediated dearomatization for synthesizing series of pyrroloindolines via N-heterocyclic carbene catalysis. In this organocatalytic process, the Breslow enolate served as both single electron donor acyl radical equivalent to assemble C3a-acyl with broad substrate scope. Sequential reduction indole derivatives provided analogues (±)-desoxyeseroline, which exhibited potential anticancer activity.

Language: Английский

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Photoinduced Dehalocyclization to Access Oxindoles Using Formate as a Reductant

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(11), P. 1203 - 1208

Published: Feb. 6, 2024

Comprehensive Summary Herein, we report an efficient and practical protocol for the photoinduced dehalocyclization of ortho ‐halophenylacrylamides with formate by engagement a CO 2 radical anion to access substituted oxindoles. This method proceeds smoothly under mild conditions exhibits wide range substrate as well remarkable functional group compatibility.

Language: Английский

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