Heterogeneous Photocatalytic Strategies for C(sp³)−H Activation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(13)

Published: Jan. 16, 2024

Abstract Activation of ubiquitous C(sp 3 )−H bonds is extremely attractive but remains a great challenge. Heterogeneous photocatalysis offers promising and sustainable approach for activation has been fast developing in the past decade. This Minireview focuses on mechanism strategies heterogeneous photocatalytic activation. After introducing mechanistic insights, including precise design active sites, regulation reactive radical species, improving charge separation reactor innovations are discussed. In addition, recent advances hydrocarbons, alcohols, ethers, amines amides by summarized. Lastly, challenges opportunities outlined to encourage more efforts development this exciting field.

Language: Английский

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The Carbene Chemistry of N-Sulfonyl Hydrazones: The Past, Present, and Future

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

N-Sulfonyl hydrazones have been extensively used as operationally safe carbene precursors in modern organic synthesis due to their ready availability, facile functionalization, and environmental benignity. Over the past two decades, there has tremendous progress chemistry of N-sulfonyl presence transition metal catalysts, under metal-free conditions, or using photocatalysts photoirradiation conditions. Many transfer reactions are unique cannot be achieved by any alternative methods. The discovery novel development highly enantioselective new skeletal editing represent notable recent achievements hydrazones. This review describes overall made hydrazones, organized based on reaction types, spotlighting current state-of-the-art remaining challenges addressed future. Special emphasis is devoted identifying, describing, comparing scope limitations methodologies, key mechanistic scenarios, potential applications complex molecules.

Language: Английский

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Photochemical Carbene Transfer Reactions of Aryl/Aryl Diazoalkanes—Experiment and Theory**

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(24), P. 13271 - 13279

Published: March 9, 2021

Controlling the reactivity of carbene intermediates is a key parameter in development selective transfer reactions and usually achieved by metal complexes via singlet metal-carbene intermediates. In this combined experimental computational studies, we show that free diaryl carbenes can be controlled electronic properties substituents without need external additives. The introduction electron-donating -withdrawing groups results significant perturbation triplet energy splitting intermediate activation energies consecutive reactions. This strategy now overcomes long-standing paradigm allows realization highly chemoselective with alkynes. We could readily accessed photolysis corresponding diazo compounds these undergo cyclopropenation, cascade, or C-H functionalization Experimental theoretical mechanistic analyses confirm participation different spin states rationalize for observed reactivity.

Language: Английский

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Enantioselective Diarylcarbene Insertion into Si–H Bonds Induced by Electronic Properties of the Carbenes

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(28), P. 12394 - 12399

Published: June 16, 2020

Catalytic enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered carbene Si-H insertion which the enantioselectivity primarily electronic characteristics of substrate, log(er) values are linearly related to Hammett parameters. A new class tetraphosphate dirhodium catalysts was developed; it shows excellent activity for diarylcarbenes into bond silanes. Computational mechanistic studies show how two aryls lead energies diastereomeric transition states. This study provides strategy asymmetric catalysis exploiting properties substrates.

Language: Английский

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Cu-catalysed intramolecular radical enantioconvergent tertiary β-C(sp3)–H amination of racemic ketones

Nature Catalysis, Journal Year: 2020, Volume and Issue: 3(7), P. 539 - 546

Published: May 18, 2020

Language: Английский

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