Heterogeneous M-N-C Catalysts for Aerobic Oxidation Reactions: Lessons from Oxygen Reduction Electrocatalysts

Chemical Reviews, Год журнала: 2022, Номер 123(9), С. 6233 - 6256

Опубликована: Окт. 5, 2022

Nonprecious metal heterogeneous catalysts composed of first-row transition metals incorporated into nitrogen-doped carbon matrices (M-N-Cs) have been studied for decades as leading alternatives to Pt the electrocatalytic O

Язык: Английский

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Heterogeneous Iridium-Catalyzed Carbene N–H Bond Insertion with α-Alkyl Diazo Esters

ACS Catalysis, Год журнала: 2024, Номер 14(7), С. 4690 - 4698

Опубликована: Март 13, 2024

A heterogeneous iridium single-atom site catalyst (Ir-SA) was synthesized and investigated in catalyzing the carbene insertion reaction with challenging α-alkyl diazo ester substrates. With only 0.23 mol % loading, our Ir-SA demonstrated remarkable performance N–H bond reactions involving various (hetero) aryl amines coupled esters. Notably, case of using a chiral diamino substrate two reactive sites, exhibited high selectivity toward single insertion, leading to generation class unsymmetric ligands. Further mechanism study revealed that lower activation barrier associated step, as compared either β-hydride elimination or downstream dual accounted for observed this catalyzed by Ir-SA.

Язык: Английский

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Porous carbon catalysis in sustainable synthesis of functional heterocycles: An overview

Chinese Chemical Letters, Год журнала: 2024, Номер 35(8), С. 109472 - 109472

Опубликована: Янв. 1, 2024

Язык: Английский

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N, S Co-Coordinated Zinc Single-Atom Catalysts for N-Alkylation of Aromatic Amines with Alcohols: The Role of S-Doping in the Reaction

Nanomaterials, Год журнала: 2023, Номер 13(3), С. 445 - 445

Опубликована: Янв. 21, 2023

S-doping emerged as a promising approach to further improve the catalytic performance of carbon-based materials for organic synthesis. Herein, facile and gram-scale strategy was developed using zeolitic imidazole frameworks (ZIFs) precursor fabrication ZIF-derived N, S co-doped carbon-supported zinc single-atom catalyst (CNS@Zn1-AA) via pyrolysis S-doped ZIF-8, which modified by aniline, ammonia thiourea prepared one-pot ball milling at room temperature. This catalyst, in Zn is dispersed single atom, displays superior activity N-alkylation hydrogen-borrowing (120 °C, turnover frequency (TOF) up 8.4 h−1). significantly enhanced CNS@Zn1-AA, it increased specific surface area defects this material simultaneously electron density sites catalyst. Furthermore, had excellent stability recyclability, no obvious loss after eight runs.

Язык: Английский

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Three-Dimensional Mesoporous Covalent Organic Framework for Photocatalytic Oxidative Dehydrogenation to Quinoline

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 28, 2024

Developing precious metal-free catalysts for organic reactions under mild conditions is urgent. Herein, we report a three-dimensional covalent framework (3D-COF) with high crystallinity and permanent pores, termed 3D-TABPA-COF, the oxidation of tetrahydroquinoline to quinoline. The 3D-TABPA-COF assembled based on N4,N4-bis(4′-amino-[1,1′-biphenyl]-4-yl)-[1,1′-biphenyl]-4,4′-diamine (TABPA) catalytic active center conversion tetrahydroquinoline. triphenylamine in structure an effective photosensitizer, which not only enhances light absorption capacity but also facilitates rapid transfer photogenerated electrons ensures carrier separation. obtained has specific surface area (2745.06 m2 g–1) mesopores 3.57 nm. This attributed fact that bor topology easy interpenetrate. It can oxidize obtain quinoline efficiently visible irradiation. In addition, performed various photochemical characterizations combined density functional theory calculations elucidate reaction mechanism from work provides feasible strategy constructing 3D-COF achieve efficient photocatalytic reactions.

Язык: Английский

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New Insights into N-Doped Porous Carbons as Both Heterogeneous Catalysts and Catalyst Supports: Opportunities for the Catalytic Synthesis of Valuable Compounds

Nanomaterials, Год журнала: 2023, Номер 13(13), С. 2013 - 2013

Опубликована: Июль 5, 2023

Among the vast class of porous carbon materials, N-doped carbons have emerged as promising materials in catalysis due to their unique properties. The introduction nitrogen into carbonaceous matrix can lead creation new sites on surface, often associated with pyridinic or pyrrolic functionalities, which facilitate various catalytic reactions increased selectivity. Furthermore, presence N dopants exerts a significant influence properties supported metal oxide nanoparticles, including dispersion, interactions between and support, stability nanoparticles. These effects play crucial role enhancing performance carbon-supported catalysts. Thus, metals been revealed be interesting heterogeneous catalysts for relevant synthesis processes valuable compounds. This review presents concise overview methods employed produce distinct structures, starting from diverse precursors, showcases potential processes, particularly fine chemical synthesis.

Язык: Английский

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Solvent- and Additive-Free Dehydrogenation of N-Heterocycles with Oxygen Catalyzed by Polyoxovanadate-Based Metal–Organic Frameworks

Inorganic Chemistry, Год журнала: 2023, Номер 62(49), С. 20228 - 20235

Опубликована: Ноя. 21, 2023

N-heteroarenes are a family of organics with significant chemical and pharmaceutical applications. They generally prepared by the catalytic oxidative dehydrogenation (ODH) partially saturated N-heterocycles. In this work, we prepare demonstrate ODH applications two polyoxovanadate-based metal–organic frameworks general formula {[MII(bibp)1.5][VV2O6]}·H2O (M = Ni 1, Co 2; bibp 4,4′-bis(imidazol-1-ylmethyl)biphenyl). based on nonprecious metals, need no additives or organic solvents typically required for ODH, utilize molecular O2 as oxidant, thus possessing all traits desirable practical catalysis. Catalyst 1 shows tolerance range substrates different electronic steric features, including 2,3-dihydro-1H-indole tetrahydroquinolines substituted various functional groups. Mechanistic studies supported primarily evidence from electron paramagnetic resonance X-ray photoelectron spectra suggest that VV sites in catalytically responsible, first enabling formation substrate-based radical species single transfer event while being converted into its mixed-valence form, followed production superoxide anion (O2•–) upon contact O2. The reaction mixture containing O2•– initially formed then undergoes series steps, hydrogen abstraction hydroperoxyl radical, tautomerization dehydrogenated intermediate, finally repeating cycle aforementioned to achieve high-yield conversion corresponding N-heteroarenes.

Язык: Английский

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A Cobalt Nanocatalyst for the Hydrogenation and Oxidative Dehydrogenation of N‐heterocycles

ChemCatChem, Год журнала: 2023, Номер 16(1)

Опубликована: Сен. 26, 2023

Abstract Catalytic hydrogenation and oxidative dehydrogenation of N‐heterocycles to produce tetrahydroquinoline quinoline derivatives are important reactions particular importance in the agrochemical pharmaceutical industries. Herein, we report earth‐abundant cobalt nanoparticles supported on hydroxyapatite (HAP) as an inexpensive efficient catalyst for reverse N‐heterocycles. The optimal nanocatalyst exhibits excellent activity both a wide range substrates including (iso)quinolines, acridine, benzo[ h ]quinoline, quinoxaline indole. Reactions proceed under relatively mild conditions without requiring any additives.

Язык: Английский

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Eco‐sustainable Synthesis of N‐containing Heterocyclic Systems Using Porous Carbon Catalysts

ChemCatChem, Год журнала: 2023, Номер 15(23)

Опубликована: Окт. 16, 2023

Abstract From the most classic carbon materials (CMs) to advanced ones, all of them integrate a promising catalyst set in terms sustainability and energy efficiency for greener future. Different synthetic strategies concerning catalytic synthesis relevant N ‐containing heterocycles are herein described address great potential referred catalysts flying over what has been done that remains be done. Current trends this field involve structure‐activity relationships establishment also considering reaction mechanisms understanding identification active sites, as function both experimental datasets, emphasizing on operando characterization techniques, theoretical studies which will significantly contribute design custom‐made new horizon.

Язык: Английский

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Phenalenyl-Based Photocatalyst for Bioinspired Oxidative Dehydrogenation of N-Heterocycles and Benzyl Alcohols

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(6), С. 4145 - 4155

Опубликована: Фев. 28, 2024

The environmental benefits of molecular oxygen as the oxidizing agent in oxidation reactions that synthesize fine chemicals cannot be overstated. Increased interest developing robust photocatalysts is stimulated by fact current photocatalytic transformation boom has made previously inaccessible synthetic approaches possible. Motivated enzymatic catalysis, employing a reusable phenalenyl-based photocatalyst, we have successfully developed oxidative dehydrogenation utilizing greener oxidant. Under photoinduced conditions, different types saturated N-heterocycles and alcohols were dehydrogenated. versatility this bioinspired protocol demonstrated wide variety N-heteroaromatics, such quinoline, carbazole, quinoxaline, acridine, indole derivatives, well aldehydes ketones, synthesized. Detailed mechanistic studies validate proposed mechanism. Fluorescence lifetime CV experiments revealed crucial role water on efficiency reaction. present also provides chemoselectivity scalability, leading to superior results allowing for functionalization bioactive molecules at late stage sustainable manner.

Язык: Английский

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