Photocatalytic strategies for the activation of organic chlorides

Nature Catalysis, Journal Year: 2020, Volume and Issue: 3(11), P. 872 - 886

Published: Nov. 12, 2020

Language: Английский

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Photoinduced Palladium-Catalyzed Carbofunctionalization of Conjugated Dienes Proceeding via Radical-Polar Crossover Scenario: 1,2-Aminoalkylation and Beyond

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(22), P. 9932 - 9937

Published: May 14, 2020

A photoinduced palladium-catalyzed 1,2-carbofunctionalization of conjugated dienes has been developed. This mild modular approach, which does not require employment exogeneous photosensitizers and external oxidants, allows for efficient highly regio- stereoselective synthesis a broad range allylic amines from readily available 1,3-dienes, alkyl iodides, amines. Employment O- C-nucleophiles toward oxyalkylation dialkylation products was also demonstrated. putative π-allyl palladium radical-polar crossover path is proposed as key event in this three-component coupling process. The utility protocol highlighted by its application derivatization several amine-containing drugs.

Language: Английский

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Organothianthrenium salts: synthesis and utilization

Chemical Science, Journal Year: 2022, Volume and Issue: 13(46), P. 13690 - 13707

Published: Jan. 1, 2022

This review summarizes the synthesis of diverse organothianthrenium salts from various precursors and their applications in organic to forge new C–C, C–H C–heteroatom bonds by C–S bond cleavage with different mechanistic considerations.

Language: Английский

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Generation of non-stabilized alkyl radicals from thianthrenium salts for C–B and C–C bond formation

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: July 26, 2021

Abstract Sulfonium salts bearing a positively charged sulfur atom with three organic substituents have intrigued chemists for more than century their unusual structures and high chemical reactivity. These compounds are known to undergo facile single-electron reduction emerge as valuable alternative source of aryl radicals synthesis. However, the generation non-stabilized alkyl from sulfonium has been challenge several decades. Here we report treatment S -(alkyl) thianthrenium generate key intermediates granting controlled selective outcome ensuing reactions under mild photoredox conditions. The value these reagents demonstrated through efficient construction alkylboronates other transformations, including heteroarylation, alkylation, alkenylation, alkynylation. developed method is practical, provides opportunity convert C–OH bond C–B C–C bonds.

Language: Английский

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Excited-State Palladium-Catalyzed Radical Migratory Mizoroki–Heck Reaction Enables C2-Alkenylation of Carbohydrates

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(8), P. 3353 - 3359

Published: Feb. 21, 2022

Excited-state palladium catalysis has emerged as a promising strategy for developing novel and valuable reactions. Herein, we report the first excited-state Pd-catalyzed 1,2-radical migratory Mizoroki–Heck reaction that enables C2-alkenylation of carbohydrates using readily available 1-bromosugars alkenes. The tolerates wide variety functional groups complex molecular architectures, including derivatives natural products marketed drugs. Preliminary mechanistic studies DFT calculations suggest involvement visible-light-induced photoexcitation Pd species, 1,2-spin-centered-shift (SCS) process, Heck-type cross-coupling reaction. expands reactivity profile provides streamlined protocol preparation C2-alkenylated carbohydrate mimetics to aid discovery development new therapeutics, agrochemicals, materials.

Language: Английский

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Recent Advances in Visible Light Induced Palladium Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(9)

Published: Nov. 14, 2023

Visible light-induced Pd catalysis has emerged as a promising subfield of photocatalysis. The hybrid nature radical species enabled wide array radical-based transformations otherwise challenging or unknown via conventional chemistry. In parallel to the ongoing pursuit alternative, readily available precursors, notable discoveries have demonstrated that photoexcitation can alter not only oxidative addition but also other elementary steps. This Minireview highlights recent progress in this area.

Language: Английский

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Photoinduced C(sp³)–H Functionalization of Glycine Derivatives: Preparation of Unnatural α-Amino Acids and Late-Stage Modification of Peptides

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(15), P. 2110 - 2125

Published: July 19, 2023

ConspectusPeptides are essential components of living systems and contribute to critical biological processes, such as cell proliferation, immune defense, tumor formation, differentiation. Therefore, peptides have attracted considerable attention targets for the development therapeutic products. The incorporation unnatural amino acid residues into can considerably impact peptide immunogenicity, toxicity, side effects, water solubility, action duration, distribution enhance peptides' druggability. Typically, direct modification natural acids is a practical effective approach promptly obtaining acids. However, selective functionalization multiple C(sp3)-H bonds with comparable chemical reactivities in chains remains formidable challenge. Furthermore, modifications aimed at highly reactive (nucleophilic aromatic) groups on interfere activity peptides.In recent years, rapid advancement photoinduced radical reactions has made photoredox radical-radical cross-coupling constructing C(sp3)-C(sp3) under mild conditions. Glycine, naturally occurring fundamental skeleton all α-amino acids, provides basis alkylated its own α-C(sp3)-H bond This Account describes our research endeavors systematically investigating photocatalytic alkylation glycine derivatives via coupling between N-aryl glycinate-derived radicals various alkyl radicals. In 2018, we disclosed Cu-catalyzed decarboxylative derivatives. Subsequently, developed catalyst-free method alkylating electron donor-acceptor (EDA)-complex-promoted single transfer. Moreover, glycinate using unactivated chlorides (iodides) photocatalyst-free Notably, by building racemic alkylations glycine-residue-containing peptides, recently stereoselectively dual-functional Cu catalyst generated situ synthesizing series chiral C-glycoamino acids.We methods through photoredox-promoted key strategy. These efficient versatile be used late-stage contexts. Our work builds importance basic scaffold highlights potential radical-based chemistry developing transformations synthesis. findings broad implications biology may open doors discovering drugs therapeutics.

Language: Английский

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Photoinduced, Palladium-Catalyzed Enantioselective 1,2-Alkylsulfonylation of 1,3-Dienes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(5), P. 3725 - 3732

Published: Feb. 21, 2024

The chiral allylic sulfonylated group is a unique structural motif embedded in range of natural products and pharmaceuticals. Notably, the synthesis structurally diverse derivatives via alkylsulfonylation 1,3-dienes remains underexplored because its inherent challenges stereocontrol regioselectivity. Herein, photoinduced, palladium-catalyzed enantioselective 1,2-alkylsulfonylation conjugated described. A wide variety alkyl bromides, 1,3-dienes, sodium sulfinates could be facilely coupled to generate value-added with high enantioselectivity. Finally, utility this difunctionalization protocol was demonstrated pharmaceutical analogue synthesis.

Language: Английский

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Synergistic Photoredox Catalysis and Organocatalysis for Inverse Hydroboration of Imines

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(15), P. 3990 - 3994

Published: Feb. 15, 2018

The first catalytic inverse hydroboration of imines with N-heterocyclic carbene (NHC) boranes has been realized by means cooperative organocatalysis and photocatalysis. This combination provides a promising platform for promoting NHC-boryl radical chemistry under sustainable radical-initiator-free conditions. highly important functional-group compatibility possible application in late-stage hydroborations represent an step forward to enhanced α-amino organoboron library.

Language: Английский

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Heck Reaction of Electronically Diverse Tertiary Alkyl Halides

Organic Letters, Journal Year: 2018, Volume and Issue: 20(2), P. 357 - 360

Published: Jan. 5, 2018

The efficient Pd-catalyzed Heck reaction of diverse tertiary alkyl halides with alkenes has been developed. Unactivated efficiently react at room temperature under visible light irradiation no exogenous photosensitizers required. For activated halides, the same catalytic system works well without light. These methods offer a general access to electronically possessing quaternary and functionalized allylic carbon centers. substituents these centers include alkyl-, carbalkoxy-, tosyl-, phosphonyl-, boronate groups. It was also shown that end-game mechanism this transformation may vary depending on type substrates used.

Language: Английский

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