A general electron donor–acceptor complex for photoactivation of arenes via thianthrenation

Chemical Science, Journal Year: 2022, Volume and Issue: 13(19), P. 5659 - 5666

Published: Jan. 1, 2022

General photoactivation of EDA complexes between arylsulfonium salts and 1,4-diazabicyclo[2.2.2]octane was discovered. This practical mode enables the generation aryl radicals for C–H functionalization arenes.

Language: Английский

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Phosphine/Photoredox Catalyzed Anti-Markovnikov Hydroamination of Olefins with Primary Sulfonamides via α-Scission from Phosphoranyl Radicals

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(43), P. 18331 - 18338

Published: Oct. 21, 2021

New strategies to access radicals from common feedstock chemicals hold the potential broadly impact synthetic chemistry. We report a dual phosphine and photoredox catalytic system that enables direct formation of sulfonamidyl primary sulfonamides. Mechanistic investigations support N-centered radical is generated via α-scission P-N bond phosphoranyl intermediate, formed by sulfonamide nucleophilic addition cation. As compared recently well-explored β-scission chemistry radicals, this strategy applicable activation N-based nucleophiles in phosphine. highlight application an intermolecular anti-Markovnikov hydroamination unactivated olefins with A range structurally diverse secondary sulfonamides can be prepared good excellent yields under mild conditions.

Language: Английский

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Merging Carbonyl Addition with Photocatalysis

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(8), P. 1135 - 1147

Published: March 31, 2022

The carbonyl group stands as a fundamental scaffold and plays ubiquitous role in synthetically important chemical reactions both academic industrial contexts. Venerable transformations, including the aldol reaction, Grignard Wittig Nozaki-Hiyama-Kishi constitute vast empowering synthetic arsenal. Notwithstanding, two-electron mechanisms inherently confine breadth of accessible reactivity topological patterns.Fostered by rapid development photoredox catalysis, combing well-entrenched addition radicals can harness several unique increasingly sustainable transformations. In particular, unusual carbon-carbon carbon-heteroatom disconnections, which are out reach chemistry, be conceived. To meet this end, novel strategy toward utilization simple compounds intermolecular radical acceptors was developed. reaction is enabled visible-light photoredox-initiated hole catalysis. situ Brønsted acid activation moiety prevents β-scission from occurring. Furthermore, regioselective alkyl obviates use metals, ligands, or additives, thus offering high degree atom economy under mild conditions. On basis same concept work Schindler co-workers, carbonyl-olefin cross-metathesis, induced visible light, has also been achieved, leveraging Prins-elimination sequence.Recently, dual chromium catalysis developed us Kanai, complementary approach to revered reaction. Leveraging intertwined synergy between light metal, radical-to-polar crossover transformations eminent molecular motifs have Reactions such redox-neutral allylation aldehydes alkylation harvest power enable catalytic metal. Overall, exquisite levels diastereoselectivity enforced via highly compact transition states. Other examples, dialkylation 1,3-dienes propargylation portray versatile combination multicomponent coupling endeavors. Highly valuable motifs, commonly occur complex drug natural product architectures, now accessed single operational step. Going beyond addition, seminal contributions Fagnoni MacMillan preconized photocatalytic HAT-based acyl formation key aldehyde valorization strategy. Our articulated concept, carboxy hydrogen abstractors regio- chemoselective alkynylation trifluoromethylthiolation.This Account, narrative our others' at interface radical-based photochemistry, aims provide core guiding foundations disruptive developments. We envisage that extending crossovers manifolds, taming less-activated carbonyls, processes, merging electron steps with energy-transfer events will propel breakthroughs near future.

Language: Английский

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Deoxygenative Functionalizations of Aldehydes, Ketones and Carboxylic Acids

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(10)

Published: Nov. 15, 2021

The simple and efficient conversion of carbonyl compounds into functionalized alkanes via deoxygenation is highly enabling in chemical synthesis. This Review covers the recent methodology development carboxyl deoxygenative functionalizations, highlighting some representative significant contributions this field. These advances are categorized based on reactivity patterns oxygenated feedstock compounds, including aldehydes, ketones carboxylic acids. Four types reactive intermediates arising from aldehydes during deoxygenation, namely, bis-electrophiles, carbenoids, bis-nucleophiles alkyl radical equivalents, presented, while acids mainly behave as tris-electrophiles when deoxygenated. In each subcategory, selected examples organized according to type bond formation discussed a generalized mechanistic perspective.

Language: Английский

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Decarboxylative tandem C-N coupling with nitroarenes via SH2 mechanism

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: May 4, 2022

Abstract Aromatic tertiary amines are one of the most important classes organic compounds in chemistry and drug discovery. It is difficult to efficiently construct from primary via classical nucleophilic substitution due consecutive overalkylation. In this paper, we have developed a radical tandem C-N coupling strategy aromatic commercially available carboxylic acids nitroarenes. A variety can be furnished good yields (up 98%) with excellent functional group compatibility under mild reaction conditions. The use two different also allows for concise synthesis nonsymmetric satisfactory yields. Mechanistic studies suggest intermediacy arylamine–(TPP)Fe(III) species might provide possible evidence an S H 2 (bimolecular homolytic substitution) pathway critical bond formation step.

Language: Английский

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Recent Advances in Visible-Light-Mediated Amide Synthesis

Molecules, Journal Year: 2022, Volume and Issue: 27(2), P. 517 - 517

Published: Jan. 14, 2022

Visible-light photoredox catalysis has attracted tremendous interest within the synthetic community. As such, activation mode potentially provides a more sustainable and efficient platform for of organic molecules, enabling invention many controlled radical-involved reactions under mild conditions. In this context, amide synthesis via strategy received growing due to ubiquitous presence structural motif in numerous natural products, pharmaceuticals functionalized materials. Employing strategy, wide variety amides can be prepared effectively from halides, arenes even alkanes irradiation visible light. These methods provide robust alternative well-established strategies that involve condensation between carboxylic acid amine mediated by stoichiometric activating agent. review, representative progresses made on through light-mediated radical are summarized.

Language: Английский

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A general electron donor–acceptor complex enabled cascade cyclization of alkynes to access sulfur-containing heterocycles

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(8), P. 3111 - 3116

Published: Jan. 1, 2023

A general visible light-promoted and electron–donor–acceptor complex-enabled cascade reaction of alkynes to produce functionalized sulfur-containing heterocycles under photocatalyst-, base-, oxidant- metal-free conditions was developed.

Language: Английский

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Radical thioesterification via nickel-catalysed sensitized electron transfer

Nature Synthesis, Journal Year: 2023, Volume and Issue: 2(11), P. 1116 - 1126

Published: July 10, 2023

Abstract Multi-catalytic reaction modes have attracted widespread attention in synthetic chemistry. The merger of nickel catalysis with photoredox has offered a powerful platform for synthesis molecules attractive properties. Nonetheless, the conceptual development nickel-catalysed, sensitized electron transfer is pivotal relevance, but still greatly limited. Here we describe radical cross-thioesterification process by nickel-catalysed transfer. strategy can produce diverse methyl thioesters, which are not only found natural products, materials and pharmaceuticals also precursors chemistry biological processes. This catalytic mode features high chemoselectivity, good functional group tolerance excellent scalability. Perhaps more important was finding that various drugs amino acids were successfully functionalized this system. Experimental studies, nanosecond transient spectroscopic analysis, density theory calculations reveal photocatalytic transfer, energy plays an essential role thioesterification reaction.

Language: Английский

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Umpolung strategies for the functionalization of peptides and proteins

Chemical Science, Journal Year: 2022, Volume and Issue: 13(10), P. 2809 - 2823

Published: Jan. 1, 2022

This perspective highlights the growing body of literature that leverages polarity reversal (umpolung reactivity) for selective modification proteinogenic functionalities and identifies opportunities further innovation.

Language: Английский

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Mild Amide Synthesis Using Nitrobenzene under Neutral Conditions

Organic Letters, Journal Year: 2022, Volume and Issue: 24(26), P. 4766 - 4771

Published: June 27, 2022

Amide synthesis is one of the most important transformations in organic chemistry due to broad application pharmaceutical drugs and materials. In this report, we describe a mild protocol for amide formation using readily available nitroarenes as nitrogen sources an inexpensive iron complex catalyst. Because use pH-neutral conditions avoidance strong oxidant or reductant, wide range aromatic aliphatic aldehydes well with various functional groups could be tolerated well. A plausible mechanism proposed based on detailed studies, which catalyst initiates radical process solvent plays key role O-atom acceptor.

Language: Английский

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