Decyanative Heteroarylations of Glycine Derivatives

Organic Letters, Journal Year: 2024, Volume and Issue: 26(25), P. 5323 - 5328

Published: June 17, 2024

Amino acids and aromatic nitrogen heterocycles are widely used in pharmaceuticals. Herein, we present an effective visible-light-driven thiobenzoic acid (TBA)-catalyzed decyanative C(sp3)–H heteroarylation of glycine derivatives. This process occurs under mild straightforward conditions, affording a range valuable yet challenging-to-obtain α-heteroaryl amino Moreover, this organocatalytic C(sp3)–C(sp2) bond formation reaction is applicable to the late-stage modification various short peptides.

Language: Английский

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Direct C(sp³)–H Arylation of Unprotected Benzyl Anilines and Alkylarenes by Organocatalysis under Visible Light

Organic Letters, Journal Year: 2024, Volume and Issue: 26(1), P. 304 - 309

Published: Jan. 2, 2024

Reported herein is direct C(sp3)–H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles radical–radical cross-coupling were involved, paramagnetic resonance experiments provide evidence for the formation radical intermediates formed in situ. The protocol highlights transition metal free, external oxidant broad substrate scope, high efficiency (>60 examples, up to 96%).

Language: Английский

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Photoinduced Radical Desulfurative C(sp³)–C(sp²) Coupling via Electron Donor–Acceptor Complexes

Organic Letters, Journal Year: 2024, Volume and Issue: 26(7), P. 1495 - 1500

Published: Feb. 9, 2024

Herein, we disclose a radical desulfurative C–C coupling protocol for the synthesis of 4-alkylpyridines. A variety substituents on both benzyl thiols and 4-cyanopyridines are tolerated. The reaction is carried out under mild photocatalyst- transition-metal-free conditions. Preliminary mechanistic studies show that an electron donor–acceptor complex formed between alkaline Then, 1°, 2°, 3° C(sp3)-centered radicals was by cleavage C–S bond, 4-alkylpyridines were achieved through radical–radical with pyridyl anion.

Language: Английский

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Photocatalytic redox-neutral α-C(sp³)–H pyridination of glycine derivatives and N-arylamines with cyanopyridines

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(33), P. 4451 - 4454

Published: Jan. 1, 2024

Photocatalytic α-C(sp 3 )–H pyridination of N -arylglycine derivatives and -arylamines with cyanopyridines was developed through radical–radical cross-coupling under redox-neutral conditions.

Language: Английский

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Unified approaches in transition metal catalyzed C(sp³)–H functionalization: recent advances and mechanistic aspects

Chemical Society Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Direct alteration of unactivated C–H bonds organic building blocks.

Language: Английский

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Switchable Direct Oxygenative Arylation of C(sp³)–H Bonds via Electrophotocatalysis

Organic Letters, Journal Year: 2023, Volume and Issue: 25(27), P. 5067 - 5072

Published: June 30, 2023

A metal-free electrophotochemical C(sp3)-H arylation was developed under mild conditions. This method enables a switchable synthesis of diaryl alcohols and alkanes from inactive benzylic carbons. More importantly, cheap safe mediator N-chlorosuccinimide (NCS) developed, which employed for the hydrogen atom transfer (HAT) process C–H bond. In addition, this active radical captured identified by electron paramagnetic resonance (EPR).

Language: Английский

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Photoredox Enabled Defluorinative Benzylation of Trifluoromethyl Alkenes with Alkylarenes

Organic Letters, Journal Year: 2023, Volume and Issue: 26(1), P. 100 - 105

Published: Dec. 26, 2023

Herein, we report a photoredox enabled defluorinative benzylation of trifluoromethyl alkenes with readily available alkylarenes, which provides convenient access to series structurally valuable benzylated gem-difluoroalkenes under mild reaction conditions. The synthetic value this protocol has been demonstrated by the transformations several substrates bearing drug moieties, gram-scale reactions, and various further derivatizations gem-difluoroalkene products. preliminary mechanistic investigations suggest pathway rate-determining benzyl C–H bond cleavage toluene followed benzylic radical formation.

Language: Английский

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Visible-Light-Induced Stoichiometric Coupling of Alkylarenes and Trifluoromethyl Ketones

Organic Letters, Journal Year: 2023, Volume and Issue: 25(20), P. 3800 - 3805

Published: May 17, 2023

A visible-light induced direct C(sp3)-H functionalization of alkylarenes with trifluoromethyl ketones has been reported to access valuable benzyl-substituted alcohols in a stoichiometric manner. Readily available petroleum-derived are employed as latent benzylation reagents. With bromine radical the hydrogen atom transfer reagent, primary, secondary, and tertiary benzyl C–H bonds suitable coupling partners. Additionally, late-stage modification bioactive molecules highlights potential application this approach.

Language: Английский

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Transition-Metal and Photocatalyst-Free, Redox-Neutral Heteroarylation of C(sp³)–H Bonds

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(16), P. 12664 - 12670

Published: Aug. 7, 2024

Developing a transition-metal-free system for functionalizing the C(sp3)–H bond has posed long-standing challenge in synthetic organic chemistry and is of significance drug discovery. In this context, we present straightforward protocol heteroarylation benzylic alpha-amino C–H bonds, achieved without transition metals or photocatalysts. A pivotal aspect redox-neutral hydroarylation utilization commercially available triisopropylsilanethiol (iPr3SiSH) as an organocatalyst. This organocatalyst serves dual function forming electron donor–acceptor complex (EDA) acting hydrogen atom transfer catalyst, generating alkyl/benzylic radicals from corresponding bonds. Applying mild methodology, various amino bonds were functionalized to give C(sp2)–heteroaryl C–C cross-coupled product. To demonstrate practical utility protocol, pyridine was incorporated into molecule via late-stage modification. Additionally, gram-scale reaction also performed show advantages protocol.

Language: Английский

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Dual anion and cation catalysis enabled by an ion-pairing photocatalyst

Organic Chemistry Frontiers, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A dual catalysis involving both anionic and cationic species of an ion-pairing photocatalyst is achieved. By adopting this mode action, photocatalytic hydrogen transfer cross-coupling reactions can be enabled using a single photocatalyst.

Language: Английский

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