Amine‐Free, Directing‐Group‐Free and Redox‐Neutral α‐Alkylation of Saturated Cyclic Ketones

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(29)

Published: May 23, 2023

Abstract The activation of the α‐C−H bond ketones typically requires an amine and a directing group to guide reaction selectivity in amine‐catalysis carbonyl chemistry. For ketone, groups are also required control selectivity. Reported herein is first α‐alkylation cyclic absence catalyst group. 1 H NMR, XPS, EPR studies DFT calculations indicate that α‐carbon radical intermediate formed through direct selective inert chelating on surface colloidal quantum dots (QDs). Such interaction essential for weakening C−H bond, as exemplified, using CdSe QDs sole photocatalyst execute alkylation under visible‐light irradiation. Without group, high step‐ atom‐economy transformation redox‐neutral condition opens new way functionalization

Language: Английский

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Divergent Photosensitizer Controlled Reactions of 4‐Hydroxycoumarins and Unactivated Olefins: Hydroarylation and Subsequent [2+2] Cycloaddition

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(45)

Published: Sept. 26, 2023

Herein, we report a photoinduced approach for hydroarylation of unactivated olefins using 4-hydroxycoumarins as the arylating reagent. Key to success this reaction is conversion nucleophilic into electrophilic carbon radicals via photocatalytic arene oxidation, which not only circumvents polarity-mismatch issue encountered under ionic conditions but also accommodates broad substrate scope and inhibits side reactions that were previously observed. Moreover, divergent reactivity was achieved by changing photocatalyst, enabling subsequent [2+2] cycloaddition deliver cyclobutane-fused pentacyclic products are otherwise challenging access in high yields with diastereoselectivity. Mechanistic studies have elucidated mechanism origin reactivity.

Language: Английский

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Photocatalytic Cracking of non‐Biodegradable Plastics to Chemicals and Fuels

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(35)

Published: June 19, 2024

Plastic pollution is worsening the living conditions on Earth, primarily due to toxicity and stability of non-biodegradable plastics (NBPs). Photocatalytic cracking NBPs emerging as a promising way cleave inert C-C bonds abstract carbon atoms from these wastes into valuable chemicals fuels. However, controlling processes huge challenge, ascribed complicated reactions various NBPs. Herein, we summarize recent advances in CO

Language: Английский

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Solar Fuel Synthesis Using a Semiartificial Colloidal Z-Scheme

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(43), P. 29865 - 29876

Published: Oct. 16, 2024

The integration of enzymes with semiconductor light absorbers in semiartificial photosynthetic assemblies offers an emerging strategy for solar fuel production. However, such colloidal biohybrid systems rely currently on sacrificial reagents, and semiconductor-enzyme powder that couple production to water oxidation are therefore needed mimic overall reaction. Here, we present a Z-scheme enzyme system produces electrons sourced from water. This "closed-cycle" approach utilizes particulate SrTiO

Language: Английский

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Organic Photocatalysts for Wastewater Decontamination

Journal of Photochemistry and Photobiology C Photochemistry Reviews, Journal Year: 2025, Volume and Issue: unknown, P. 100689 - 100689

Published: Jan. 1, 2025

Language: Английский

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