Visible Light-Driven Radical-Mediated C–C Bond Cleavage/Functionalization in Organic Synthesis

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(1), P. 506 - 561

Published: May 29, 2020

Thermal C–C bond cleavage reactions allow the construction of structurally diverse molecular skeletons via predictable and efficient reorganizations. Visible light photoredox-catalyzed radical-mediated have recently emerged as a powerful alternative method for overcoming thermodynamic kinetic barrier in scaffolds. In recent years, plethora elegant useful been invented, products are sometimes otherwise inaccessible by classic thermal reactions. Considering great influence synthetic potential these reactions, we provide summary state art visible light-driven cleavage/functionalization strategies with specific emphasis on working models. We hoped that this review will be medicinal organic chemists inspire further reaction development interesting area.

Language: Английский

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Photoredox-Catalyzed C–H Functionalization Reactions

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1925 - 2016

Published: Sept. 29, 2021

The fields of C–H functionalization and photoredox catalysis have garnered enormous interest utility in the past several decades. Many different scientific disciplines relied on strategies including natural product synthesis, drug discovery, radiolabeling, bioconjugation, materials, fine chemical synthesis. In this Review, we highlight use reactions. We separate review into inorganic/organometallic catalysts organic-based catalytic systems. Further subdivision by reaction class─either sp2 or sp3 functionalization─lends perspective tactical for these methods synthetic applications.

Language: Английский

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Toolbox for Distal C–H Bond Functionalizations in Organic Molecules

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(6), P. 5682 - 5841

Published: Oct. 18, 2021

Transition-metal-catalyzed C–H activation has developed a contemporary approach to the omnipresent area of retrosynthetic disconnection. Scientific researchers have been tempted take help this methodology plan their synthetic discourses. This paradigm shift helped in development industrial units as well, making synthesis natural products and pharmaceutical drugs step-economical. In vast zone bond activation, functionalization proximal bonds gained utmost popularity. Unlike bonds, distal is more strenuous requires distinctly specialized techniques. review, we compiled various methods adopted functionalize mechanistic insights within each these procedures, scope methodology. With give complete overview expeditious progress made field organic chemistry while also highlighting its pitfalls, thus leaving open for further modifications.

Language: Английский

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Strategies to Generate Nitrogen-centered Radicals That May Rely on Photoredox Catalysis: Development in Reaction Methodology and Applications in Organic Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2353 - 2428

Published: Oct. 8, 2021

For more than 70 years, nitrogen-centered radicals have been recognized as potent synthetic intermediates. This review is a survey designed for use by chemists engaged in target-oriented synthesis. summarizes the recent paradigm shift access to and application of N-centered enabled visible-light photocatalysis. broadens streamlines approaches many small molecules because photocatalysis conditions are mild. Explicit attention paid innovative advances N–X bonds radical precursors, where X = Cl, N, S, O, H. clarity, key mechanistic data noted, available. Synthetic applications limitations summarized illuminate tremendous utility photocatalytically generated radicals.

Language: Английский

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Cleavage of Carbon–Carbon σ-Bonds of Four-Membered Rings

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(1), P. 264 - 299

Published: Sept. 23, 2020

This article reviews synthetic transformations involving cleavage of a carbon-carbon bond four-membered ring, with particular focus on the examples reported during period from 2011 to end 2019. Most significant is progress catalytic reactions oxidative addition bonds onto transition metals or β-carbon elimination metal alkoxides. When they are looked at perspectives, offer unique and efficient methods build complex natural products structures that difficult construct by conventional methods. On other hand, β-scission radical intermediates has also attracted increasing attention as an alternative elementary step cleave bonds. Its site-selectivity often complementary metal-catalyzed reactions. In addition, Lewis acid-mediated thermally induced ring-opening cyclobutanone derivatives garnered renewed attention. whole, these demonstrate potentials structurally strained ring compounds for construction organic skeletons.

Language: Английский

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δ C–H (hetero)arylationviaCu-catalyzed radical relay

Chemical Science, Journal Year: 2018, Volume and Issue: 10(4), P. 1207 - 1211

Published: Nov. 9, 2018

A Cu-catalyzed strategy has been developed that harnesses a radical relay mechanism to intercept distal C-centered for C-C bond formation. This approach enables selective δ C-H (hetero)arylation of sulfonamides via intramolecular hydrogen atom transfer (HAT) by an N-centered radical. The is both initiated and terminated Cu catalyst, which incorporation arenes heteroarenes cross-coupling with boronic acids. broad scope utility this catalytic method arylation shown, along mechanistic probes selectivity the HAT mechanism. catalytic, asymmetric variant also presented, as well accessing 1,1-diaryl-pyrrolidines iterative functionalizations.

Language: Английский

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Synthesis of Sterically Hindered Primary Amines by Concurrent Tandem Photoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(2), P. 987 - 998

Published: Jan. 6, 2020

Primary amines are an important structural motif in active pharmaceutical ingredients (APIs) and intermediates thereof, as well members of ligand libraries for either biological or catalytic applications. Many chemical methodologies exist amine synthesis, but the direct synthesis primary with a fully substituted α carbon center is underdeveloped area. We report method which utilizes photoredox catalysis to couple readily available O-benzoyl oximes cyanoarenes synthesize α-carbons. also demonstrate that this enables α-trifluoromethyl functionality. Based on experimental computational results, we propose mechanism where photocatalyst engages concurrent tandem by reacting oxime triplet sensitizer first cycle reductant toward cyanoarene second achieve hindered via heterocoupling radicals from oximes.

Language: Английский

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Aliphatic Radical Relay Heck Reaction at Unactivated C(sp³)−H Sites of Alcohols

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(6), P. 1794 - 1798

Published: Nov. 21, 2018

Abstract The Mizoroki–Heck reaction is one of the most efficient methods for alkenylation aryl, vinyl, and alkyl halides. Given its innate nature, this protocol requires employment compounds possessing a halogen atom at site functionalization. However, accessibility organic molecules particular in aliphatic systems extremely limited. Thus, that allows Heck to occur specific nonfunctionalized C(sp 3 )−H desirable. Reported here radical relay which selective remote alcohols unactivated β‐, γ‐, δ‐C(sp sites. use an easily installed/removed Si‐based auxiliary enables I‐atom/radical translocation events C−H sites followed by reaction. Notably, proceeds smoothly under mild visible‐light‐mediated conditions room temperature, producing highly modifiable valuable alkenol products from readily available feedstocks.

Language: Английский

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N‐Centered Radical Directed Remote C−H Bond Functionalization via Hydrogen Atom Transfer

Chemistry - An Asian Journal, Journal Year: 2020, Volume and Issue: 15(6), P. 651 - 672

Published: Feb. 3, 2020

The N-centered radical directed remote C-H bond functionalization via hydrogen-atom-transfer at distant sites has developed as an enormous potential tool for the organic synthetic chemists. Unactivated and secondary tertiary, well selected primary bonds, can be utilized by following these methodologies. synthesis of heterocyclic scaffolds provides them extra attention modern days' developments in this field unactivated bonds functionalizations.

Language: Английский

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Photoredox-Catalyzed Sulfonylation ofO-Acyl Oximes via Iminyl Radicals with the Insertion of Sulfur Dioxide

Organic Letters, Journal Year: 2019, Volume and Issue: 21(13), P. 4950 - 4954

Published: June 10, 2019

A multicomponent sulfonylation of O-acyl oximes via iminyl radicals with the insertion sulfur dioxide under photoredox catalysis is achieved. This reaction oximes, potassium metabisulfite, alkenes, and nucleophiles visible-light irradiation efficient, giving rise to a range sulfones in moderate good yields. broad scope presented functional group compatibility.

Language: Английский

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