Keto-anthraquinone covalent organic framework for H2O2 photosynthesis with oxygen and alkaline water

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 26, 2024

Hydrogen peroxide photosynthesis suffers from insufficient catalytic activity due to the high energy barrier of hydrogen extraction H2O. Herein, we report that mechanochemically synthesized keto-form anthraquinone covalent organic framework which is able directly synthesize H2O2 (4784 μmol h-1 g-1 at λ > 400 nm) oxygen and alkaline water (pH = 13) in absence any sacrificial reagents. The strong alkalinity resulted formation OH-(H2O)n clusters water, were adsorbed on keto moieties within then dissociated into O2 active hydrogen, because was largely lowered. produced reacted with generate anthrahydroquinone, subsequently oxidized by produce H2O2. This study ultimately sheds light importance H2O for demonstrates synthesis achievable under conditions.

Язык: Английский

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Endogenous Photosensitizers in Human Skin

Chemical Reviews, Год журнала: 2023, Номер 123(16), С. 9720 - 9785

Опубликована: Июль 17, 2023

Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, the development sun care products. This review offers comprehensive analysis endogenous human skin, investigating connections between electronic excitation subsequent activation or damage organic biomolecules. We gather physicochemical photochemical properties key examine relationships chemical reactivity, location within primary biochemical events following solar radiation exposure, along with influence on skin physiology pathology. An important take-home message this that photosensitization allows visible light UV-A to have large effects skin. The presented here unveils potential causes continuous increase global cancer cases emphasizes limitations current protection approaches.

Язык: Английский

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Understanding the Interplay of the Brønsted Acidity of Catalyst Ancillary Groups and the Solution Components in Iron-porphyrin-Mediated Carbon Dioxide Reduction

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(6), С. 3721 - 3731

Опубликована: Фев. 2, 2024

The rapid and efficient conversion of carbon dioxide (CO2) to monoxide (CO) is an ongoing challenge. Catalysts based on iron-porphyrin cores have emerged as excellent electrochemical mediators the two proton + electron reduction CO2 CO, many design features that promote function are known. Of those features, incorporation Brønsted acids in second coordination sphere iron ion has a significant impact catalyst turnover kinetics. often form hydroxyphenyl groups. Herein, we explore how acidity ancillary 2-hydroxyphenyl group affects performance electrocatalysts. A series meso-5,10,15,20-tetraaryl porphyrins were prepared where only functional at 5-meso position ionizable proton. cyclic voltammetry (CV) experiments reveal complex with −OMe positioned para −OH shows largest rate constants acetonitrile solvent. This least acidic compounds surveyed. frequency derivative can be further improved addition 4-trifluoromethylphenol solution. In contrast, −CF3 opposite smallest constants, its less enhanced phenols reaction solutions. origin this effect rationalized kinetic isotope density calculations. We conclude catalysts weaker internal coupled stronger external acid additives provide superior

Язык: Английский

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Radical Brook rearrangement: past, present, and future

Chemical Society Reviews, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

This review aims to provide an overview of radical Brook rearrangement, which is organized by grouping three type reactive species generated via the unique rearrangement process.

Язык: Английский

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Photocatalytic Three-Component Reductive Coupling Synthesis of gem-Difluorohomoallyl Secondary Amines

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

Опубликована: Янв. 23, 2025

gem-Difluorohomoallyl amines, an important class of gem-difluoroalkenes, are prevalent moieties in many bioactive compounds. However, limited methods suitable for the synthesis this type compound containing secondary amines. Here, we display a photocatalytic multicomponent protocol gem-difluoroalkenes which makes use readily available materials: arylamines, alkyl aldehydes, and α-trifluoromethyl alkenes. Moreover, ketones amines also substrates. Preliminary mechanistic experiments indicate that key α-amino radical was involved, generated from reduction situ-formed imines (or iminium ions) by reduced photocatalyst. Subsequent addition to alkenes β-F elimination deliver desired products.

Язык: Английский

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Next-Generation Green Intelligent Self-Sensing Geopolymer Composites for Enhancing Construction Security and Sustainability: A Review

Composites Part B Engineering, Год журнала: 2025, Номер 295, С. 112191 - 112191

Опубликована: Фев. 1, 2025

Язык: Английский

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Nickel-mediated aerobic C(sp2)–nucleophile coupling reactions for late-stage diversification of aryl electrophiles

Nature Synthesis, Год журнала: 2025, Номер unknown

Опубликована: Янв. 16, 2025

Язык: Английский

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Inverse kinetic isotope effects in the oxygen reduction reaction at platinum single crystals

Nature Chemistry, Год журнала: 2022, Номер 15(2), С. 271 - 277

Опубликована: Ноя. 10, 2022

Язык: Английский

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Photocatalyzed Cascade Reactions of Cyclopropanols and α‐Trifluoromethyl‐Substituted Olefins for the Synthesis of Fused gem‐Difluorooxetanes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(44)

Опубликована: Сен. 16, 2022

Fluorinated fused rings are challenging to construct from simple starting materials. Herein, we report the first photocatalyzed cascade reactions of readily available cyclopropanols and α-trifluoromethyl-substituted olefins for synthesis gem-difluorooxetanes. Two three bonds were efficiently constructed in one reaction. The reaction showed broad substrate scope downstream transformations products demonstrated synthetic potential mechanistic study supported presence photoredox catalysis energy transfer catalysis/direct photo-excitation processes.

Язык: Английский

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Radical Activation of N–H and O–H Bonds at Bismuth(II)

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(36), С. 16535 - 16544

Опубликована: Сен. 2, 2022

The development of unconventional strategies for the activation ammonia (NH3) and water (H2O) is capital importance advancement sustainable chemical strategies. Herein we provide synthesis characterization a radical equilibrium complex based on bismuth featuring an extremely weak Bi–O bond, which permits in situ generation reactive Bi(II) species. ensuing organobismuth(II) engages with various amines alcohols exerts unprecedented effect onto X–H leading to low BDFEX–H. As result, N–H O–H bonds─including water─occurs seconds at room temperature, delivering well-defined Bi(III)-amido -alkoxy complexes. Moreover, demonstrate that resulting Bi(III)–N complexes engage unique reactivity pattern triad H+, H–, H• sources, thus providing alternative pathways main group chemistry.

Язык: Английский

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