Degradation of plastic wastes to commercial chemicals and monomers under visible light

Science Bulletin, Journal Year: 2023, Volume and Issue: 68(14), P. 1522 - 1530

Published: June 26, 2023

Language: Английский

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Photouranium-Catalyzed C–F Activation Hydroxylation via Water Splitting

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

Published: April 9, 2024

The C–F bond is the strongest covalent single (126 kcal/mol) in carbon-centered bonds, which highest electronegativity of fluorine (χ = 4) gives rise to shortest length (1.38 Å) and smallest van der Waals radius (rw 1.47 Å), resulting enormous challenges for activation transformation. Herein, conversion was realized via photouranium-catalyzed hydroxylation unactivated aryl fluorides using water as a hydroxyl source deliver multifunctional phenols under ambient conditions. featured cascade sequences electron transfer (SET)/hydrogen atom (HAT)/oxygen (OAT), highly integrated from excited uranyl cation. *UO22+ prompted splitting mild photoexcitation, caging active oxygen peroxo-bridged manner critical OAT process releasing hydrogen HAT process.

Language: Английский

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All-Solid-State Z-Scheme CsPbBr₃/Au/g-C₃N₄ Heterojunctions for Enhanced Photocatalytic C–H Oxidation

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 6, 2025

Z-scheme heterojunctions have emerged as a novel type of environmental and energy photocatalysts owing to their unique charge separation transfer pathways well robust redox capabilities. Herein, this paper reports straightforward technique for fabricating an anisotropic all-solid-state CsPbBr3/Au/g-C3N4 heterojunction, wherein CsPbBr3, g-C3N4, the electron-transfer system (Au) are spatially immobilized. This three-component presented high photocatalytic activity oxidation C-H bonds carboxylic acids, ketones, alcohols, respectively. Notably, metallic Au species, functioning solid-state electron mediators, can significantly accelerate rate photogenerated electrons holes between photocatalysts. As verified by trapping experiments paramagnetic resonance, results indicate that h+ ·O2- serve primary active species in process. study provides perspectives on development high-performance perovskite-based field organic synthesis.

Language: Английский

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Catalysis in the Excited State: Bringing Innate Transition Metal Photochemistry into Play

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 4665 - 4680

Published: March 5, 2025

Transition metal catalysis is an indispensable tool for organic synthesis that has been harnessed, modulated, and perfected many decades by careful selection of centers ligands, giving rise to synthetic methods with unparalleled efficiency chemoselectivity. Recent developments have demonstrated how light irradiation can also be recruited as a powerful dramatically alter the outcome catalytic reactions, providing access innovative pathways remarkable potential. In this context, adoption photochemical conditions mainstream strategy drive reactions unveiled exciting opportunities exploit rich excited-state framework transition metals applications. This Perspective examines advances in application complexes standalone photocatalysts, exploiting innate reactivity their excited states beyond common use photoredox catalysts. An account relevant examples dissected provide discussion on electronic reorganization, orbitals involved, associated different types states. analysis aims practitioners fundamental principles guiding strategies understand, design, apply light-activation homogeneous synthesis.

Language: Английский

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Chemical Upcycling of Polyolefins through C−H Functionalization

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(39)

Published: Aug. 9, 2023

Abstract Polyolefins consist of abundant hydrophobic C−C and C−H bonds, are considered as immensely potential untapped resources. Chemical upcycling offers a convenient promising recycling strategy polyolefins to produce newly‐functionalized polymeric materials, high‐value added chemicals. The significant progress made in functionalization reactions alkane molecules provides new opportunities for improving polyolefin treatments. This review focuses on recent advancements post‐modification routes, specifically the introduction C−X (X=O, N, S, halogens etc.) bonds onto chain backbones, well degradation models involving homogeneous functionalization. By emphasizing these developments, we aim highlight chemical enhancing treatment polyolefins.

Language: Английский

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Mechanism of the Visible-Light-Promoted C(sp³)–H Oxidation via Uranyl Photocatalysis

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(5), P. 2418 - 2430

Published: Jan. 24, 2024

Uranyl cation, as an emerging photocatalyst, has been successfully applied to synthetic chemistry in recent years and displayed remarkable catalytic ability under visible light. However, the molecular-level reaction mechanisms of uranyl photocatalysis are unclear. Here, we explore mechanism stepwise benzylic C-H oxygenation typical alkyl-substituted aromatics (i.e., toluene, ethylbenzene, cumene) via using theoretical experimental methods. Theoretical calculation results show that most favorable path for photocatalytic oxidation is follows: first, hydrogen atom transfer (HAT) from benzyl position form a carbon radical ([R

Language: Английский

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Uranyl Photocatalyzed Polystyrene Oxidative Degradation under Visible Light in a Green Solvent

Industrial & Engineering Chemistry Research, Journal Year: 2024, Volume and Issue: 63(11), P. 4817 - 4824

Published: March 6, 2024

Polystyrene (PS) provides a huge convenience and promotes economic social development. However, difficulties in recycling degradation of PS make waste hazardous to the environment organisms. In recent years, up-recycling PS, which turns oxygenated monomer products with added value such as benzoic acid, has attracted much attention since it into treasure offers reference for pollution treatment. Considering solubility character solvent toxicity, volatility, explosiveness, herein, we described mild, green, effective under uranyl photocatalysis. The main high-value upgrading product, was obtained. Mechanism discussed based on multianalysis gas chromatography/mass spectrometry (GC-MS), gel permeation chromatography (GPC), infrared spectrum (IR), isotopic labeling, simulations small units, so on. addition, successful application 20-g scale sunlight demonstrated potential this method utilizing solar energy degradation.

Language: Английский

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Photochemical selective difluoroalkylation reactions of bicyclobutanes: direct sustainable pathways to functionalized bioisosteres for drug discovery

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(9), P. 5512 - 5518

Published: Jan. 1, 2024

Photochemical solvent-controlled difluoromethylation and bromo-difluoromethylation reactions of bicyclobutanes are described. The method provides efficient pathways to obtain difluoroalkyl functionalized bioisosteres for drug discovery.

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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Radical cascade cyclization for the green and simple synthesis of silylated indolo[2,1-a]isoquinoline derivatives via visible light-mediated Si–H bonds activation

Chinese Chemical Letters, Journal Year: 2023, Volume and Issue: 35(1), P. 108633 - 108633

Published: June 1, 2023

Language: Английский

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