Photocatalytic Pyridine Synthesis with Enaminones and TMEDA under Metal-Free Conditions

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 11060 - 11066

Опубликована: Июль 24, 2024

Reported herein is a new photocatalytic annulation for the synthesis of 2,3,4,6-tetrasubstituted pyridines with enaminones and N,N,N′,N′-tetramethyl ethylenediamine (TMEDA). The reactions take place without requiring transition metal reagent provide products broad scope. methyl in TMEDA acts as carbon source pyridine ring construction, BrCF2CO2Et plays role terminal oxidant free radical quenching.

Язык: Английский

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Metal-free assembly of diverse polysubstituted pyridines via an efficient cascade approach using tertiary enaminones and α,β-unsaturated sulfonylketimines

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(9), С. 2607 - 2612

Опубликована: Янв. 1, 2024

A metal-free, scalable, and cascade protocol for assembling diverse polysubstituted pyridines from tertiary enaminones α,β-unsaturated sulfonylketimines by cleaving C–N/N–S bonds is reported.

Язык: Английский

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Recent Progress in C–S Bond Formation via Electron Donor-Acceptor Photoactivation

Organic & Biomolecular Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

This review summarizes recent progress in EDA complex-promoted C–S bond formation using various sulfur-containing substrates under mild conditions via visible light irradiation.

Язык: Английский

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1‐Methylpyridine‐2(1H)‐thione Photocatalyzed Giese Reaction with N‐Hydroxyphthalimide Esters via Single Electron Transfer

Chinese Journal of Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 18, 2025

Comprehensive Summary We have developed a series of 1‐methylpyridine‐2(1 H )‐thione (MPT) analogues to be used as organocatalysts. The MPT catalysts are easily prepared and bench‐stable. In our previous work, we found that the ground‐state catalyst could act nucleophile generate primary radicals via an S N 2 pathway. However, this reaction was limited benzyl radicals. Herein, reported new catalytic property catalyst. photoexcited ( E (MPT ·+ /MPT*) = –1.60 V vs. Ag/AgCl in MeCN) reduce NHPI esters through single electron transfer process. Various carbon radicals, including radical, well primary, secondary tertiary alkyl generated easily. Notably, amino acids, peptide, pharmaceuticals, other biologically active molecules modified by using methodology showing potential synthetic utility method.

Язык: Английский

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Tandem Synthesis of Polysubstituted Pyrroles via Cu(I)-Catalyzed Cyclization of Ketene N,S-Acetals with β-Ketodinitriles

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 11, 2025

A new approach to multifunctionalized pyrroles has been explored by the tandem cyclization of α-oxoketene-N,S-acetals with β-ketodinitriles using Cu(MeCN)4BF4 and Ag2CO3 in toluene under reflux conditions. The reaction involves C–C/C–N bond creation, is assumed proceed via enamine formation, intramolecular cyclization, rearrangement. potential methodology also demonstrated for a gram-scale as well some useful organic transformations. offers practical pathway achieve polysubstituted broad substrate scope good functional group tolerance.

Язык: Английский

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Photoactivation of Thianthrenium Salts: An Electron-Donor–Acceptor (EDA)-Complex Approach

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Май 14, 2025

Thianthrenium salts have emerged as one of the most versatile reagents, gaining significant popularity within synthetic community for their utility in construction C-C and C-X (X = N, O, S, P, halogens) bonds. The use photoredox transition metal catalysis with thianthrenium C-heteroatom bond formation is well established. However, these methods require elevated temperatures, expensive catalysts, ligands under stringent conditions effective execution. In contrast, photocatalysis- transition-metal-free approaches constructing bonds using salt derivatives become increasingly sought after. this regard, electron-donor-acceptor (EDA)-complex reactions a powerful strategy organic synthesis, eliminating need photocatalysts visible light irradiation. EDA-complex photochemistry exploits electron-acceptor properties salts, facilitating rapid generation radical intermediates via C-S cleavage. These play pivotal role enabling variety valuable formations. Perspective, we highlight advances EDA-complex-mediated involving mechanisms, substrate scope, limitations For sake brevity, article organized into five main sections: (1) Nitrogen-based donor reactions, (2) Oxygen-based (3) Sulfur-based (4) Phosphorus-based (5) π-based focus on C-C, C-S, C-B C-P

Язык: Английский

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Regioselective Access to 1,2,4-Triazole-Fused N-Heterocycle, Pyrrolo[1,2-a][1,2,4]triazolo[5,1-c]pyrazine, via Double Dehydrative Cyclizations

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(16), С. 11748 - 11761

Опубликована: Авг. 1, 2023

A highly efficient and regioselective approach to a novel 1,2,4-triazole-fused N-heterocyclic scaffold, pyrrolo[1,2-a][1,2,4]triazolo[3,4-c]pyrazine, was established by base-promoted reaction of pyrrole-2-carbonitrile-derived substrate with acyl hydrazide where domino double ring closures comprised enamine formation, attack on nitrile, cyclodehydration enabled sequential construction pyrazine 1,2,4-triazole systems formation three C-N bonds.

Язык: Английский

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Electron-donor-acceptor (EDA) complex-driven regioselective vicinal and oxidative geminal functionalization of alkynes†

Chemical Communications, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

A visible-light-initiated electron-donor-acceptor (EDA) complex-driven regioselective vicinal and oxidative geminal thiosulfonylation of alkynes is presented. Organic thiosulfonates act as an acceptor, producing either sulfonyl (RSO

Язык: Английский

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Pd(II)-Catalyzed Three-Component Synthesis of Furo[2,3-d]pyrimidines from β-Ketodinitriles, Boronic Acids, and Aldehydes

Organic Letters, Год журнала: 2023, Номер 25(50), С. 9070 - 9075

Опубликована: Дек. 13, 2023

A Pd(II)-catalyzed three-component synthesis of 2,4,6-triarylfuro[2,3-d]pyrimidines from β-ketodinitriles, boronic acids, and aldehydes has been developed. The participation both nitrile (-CN) groups led to the concurrent construction furo-pyrimidine via formation C-C, C═C, C-O, C-N, C═N bonds. compounds show excellent photoluminescence properties with absorption maxima ranging 348 387 nm emission 468 533 nm. synthetic utility protocol was further demonstrated through a few postsynthetic manipulations.

Язык: Английский

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Photo-triggered C-arylation of active-methylene compounds with diazonium salts via an electron donor–acceptor (EDA) complex

Chemical Communications, Год журнала: 2023, Номер 60(9), С. 1136 - 1139

Опубликована: Дек. 20, 2023

We report here the visible-light induced C -arylation of active-methylene compounds with diazonium salts via formation an electron donor–acceptor complex (EDA) under mild reaction conditions without any photocatalyst.

Язык: Английский

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