Single‐Atom Catalysis in Organic Synthesis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(34)

Published: March 15, 2023

Single-atom catalysts hold the potential to significantly impact chemical sector, pushing boundaries of catalysis in new, uncharted directions. These materials, featuring isolated metal species ligated on solid supports, can exist many coordination environments, all which have shown important functions specific transformations. Their emergence has also provided exciting opportunities for mimicking metalloenzymes and bridging gap between homogeneous heterogeneous catalysis. This Review outlines impressive progress made recent years regarding use single-atom organic synthesis. We illustrate knowledge gaps search more sustainable, earth-abundant synthetic applications.

Language: Английский

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Sustainable Aerobic Allylic C–H Bond Oxidation with Heterogeneous Iron Catalyst

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(4), P. 2769 - 2778

Published: Jan. 19, 2024

Emerging techniques are revolutionizing the realm of chemical synthesis by introducing new avenues for C–H bond functionalization, which have been exploited pharmaceuticals, natural compounds, and functional materials. Allylic oxidation alkenes serves as possibly most employed functionalization reaction. However, sustainable selective approaches remain scarce, majority existing conditions still hinge on hazardous oxidants or costly metal catalysts. In this context, we introduce a heterogeneous iron catalyst that addresses above-mentioned concerns showcasing aerobic steroids, terpenes, simple olefins to corresponding enone products. This novel method provides powerful tool arsenal allylic while minimizing environmental concerns.

Language: Английский

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Resolving the Nanostructure of Carbon Nitride‐Supported Single‐Atom Catalysts

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 9, 2025

Abstract Single‐atom catalysts (SACs) are gathering significant attention in chemistry due to their unique properties, offering uniform active site distribution and enhanced selectivity. However, precise structure often remains unclear, with multiple models proposed the literature. Understanding coordination environment of at atomic level is crucial for explaining catalytic activity. Here, a comprehensive study SACs made carbon nitride (CN x ) containing isolated nickel atoms presented. Using combination synthesis techniques characterization methods including Fourier‐transform infrared spectroscopy, X‐ray absorption spectroscopy (XAS), density functional theory (DFT) calculations, local centers CN ‐supported investigated. These results challenge conventional structural propose new architecture that better aligns current experimental evidence. This serves as foundational step toward rational approach catalyst development can facilitate more design application these innovative catalysts.

Language: Английский

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Recent advances in the accessibility, synthetic utility, and biological applications of aziridines

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(22), P. 4553 - 4573

Published: Jan. 1, 2023

Compounds featuring aziridine moieties are widely known and extensively reported in the literature. Due to their great potential from both synthetic pharmacological points of view, many researchers have focused efforts on development new methodologies for preparation transformation these interesting compounds. Over years, more ways obtain molecules bearing three-membered functional groups, which challenging due inherent reactivity, been described. Among them, several sustainable. In this review, we report recent advances biological chemical evolution derivatives, particular, variety described synthesis aziridines transformations leading formation such as 4-7 membered heterocycles pharmaceutical interest promising activities.

Language: Английский

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Reductive Coupling of Nitroarenes and HCHO for General Synthesis of Functional Ethane-1,2-diamines by a Cobalt Single-Atom Catalyst

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(31), P. 17329 - 17336

Published: July 7, 2023

Despite the extensive applications, selective and diverse access to N,N'-diarylethane-1,2-diamines remains, date, a challenge. Here, by developing bifunctional cobalt single-atom catalyst (CoSA-N/NC), we present general method for direct synthesis of such compounds via reductive coupling cheap abundant nitroarenes formaldehyde, featuring good substrate functionality compatibility, an easily accessible base metal with excellent reusability, high step atom efficiency. Mechanistic studies reveal that N-anchored single atoms (CoN4) serve as catalytically active sites reduction processes, N-doped carbon support enriches HCHO timely trap in situ formed hydroxyamines affords requisite nitrones under weak alkaline conditions, subsequent inverse electron demand 1,3-dipolar cycloaddition imines followed hydrodeoxygenation cycloadducts furnishes products. In this work, concept catalyst-controlled nitroarene create specific building blocks is anticipated develop more useful chemical transformations.

Language: Английский

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Well‐defined N₃C₁‐anchored Single‐Metal‐Sites for Oxygen Reduction Reaction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(1)

Published: Nov. 23, 2023

N-, C-, O-, S-coordinated single-metal-sites (SMSs) have garnered significant attention due to the potential for significantly enhanced catalytic capabilities resulting from charge redistribution. However, challenges persist in precise design of well-defined such SMSs, and fundamental comprehension has long been impeded case-by-case reports using carbon materials as investigation targets. In this work, molecular catalysts with N3 C1 -anchored i.e., N-confused metalloporphyrins (NCPor-Ms), are calculated their oxygen reduction activity. Then, NCPor-Ms corresponding N4 SMSs (metalloporphyrins, Por-Ms), synthesized activity evaluation. Among all, NCPor-Co reaches top established volcano plots. also shows highest half-wave 0.83 V vs. RHE, which is much better than that Por-Co (0.77 RHE). Electron-rich, low band gap regulated d-band center contribute high NCPor-Co. This study delves into examination asymmetric SMS catalysts, encompassing both theoretical experimental facets. It serves a pioneering step towards enhancing facilitating development high-performance catalysts.

Language: Английский

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Cobalt-Catalyzed Acceptorless Dehydrogenation of Primary Amines to Nitriles

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(17), P. 11801 - 11810

Published: April 16, 2024

The direct double dehydrogenation from primary amines to nitriles without an oxidant or hydrogen acceptor is both intriguing and challenging. In this paper, we describe a non-noble metal catalyst capable of realizing such transformation with high efficiency. A cobalt-centered N,N-bidentate complex was designed employed as metal–ligand cooperative catalyst. Detailed kinetic studies, control experiments, DFT calculations revealed the crucial hydride transfer, proton evolution processes. Finally, tandem outer-sphere/inner-sphere mechanism proposed for through imine intermediate.

Language: Английский

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Single-Atom Fe-Catalyzed Acceptorless Dehydrogenative Coupling to Quinolines

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(33), P. 23338 - 23347

Published: Aug. 6, 2024

A single-atom iron catalyst was found to exhibit exceptional reactivity in acceptorless dehydrogenative coupling for quinoline synthesis, outperforming known homogeneous and nanocatalyst systems. Detailed characterizations, including aberration-corrected HAADF-STEM, XANES, EXAFS, jointly confirmed the presence of atomically dispersed centers. Various functionalized quinolines were efficiently synthesized from different amino alcohols a range ketones or alcohols. The achieved turnover number (TON) up 10

Language: Английский

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

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(7), P. 4690 - 4698

Published: March 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.

Language: Английский

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Multicomponent Reductive Coupling for Selective Access to Functional γ-Lactams by a Single-Atom Cobalt Catalyst

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: March 21, 2024

Despite their significant importance to numerous fields, the difficulties in direct and diverse synthesis of α-hydroxy-γ-lactams pose substantial obstacles practical applications. Here, we designed a nitrogen TiO2 co-doped graphitic carbon-supported material with atomically dispersed cobalt sites (CoSA-N/NC-TiO2), which was successfully applied as multifunctional catalyst establish general method for construction from cheap abundant nitro(hetero)arenes, aldehydes, H2O alkynoates. The striking features operational simplicity, broad substrate functionality compatibility (>100 examples), high step atom efficiency, good selectivity, exceptional reusability highlight practicality this new catalytic transformation. Mechanistic studies reveal that active CoN4 species dopants exhibit synergistic effect on formation key acid-masked nitrones; subsequent nucleophilic addition alkynoates followed by successive reduction, alkenyl hydration, intramolecular ester ammonolysis delivers desired products. In work, concept reduction interruption leading reaction route will open door further develop useful transformations rational design.

Language: Английский

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