Visible-Light-Induced Energy-Transfer-Mediated Hydrofunctionalization and Difunctionalization of Unsaturated Compounds via Sigma-Bond Homolysis of Energy-Transfer Acceptors

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1854 - 1941

Published: Jan. 17, 2025

Over the past decade, visible-light-mediated energy-transfer (EnT) catalysis, particularly triplet–triplet (TTEnT) has emerged as a mild and environmentally friendly approach for diverse organic synthetic transformations. In contrast to photoredox which typically requires sacrificial electron donors or acceptors complete catalytic cycle, EnT photocatalysis generally proceeds with high atom economy while minimizing generation of wasteful byproducts. Furthermore, successful catalysis is contingent upon precise control redox potentials both photocatalysts substrates, strategies are primarily influenced by triplet energy compatibility between these entities. Considering growing importance photocatalysis, well hydrofunctionalization difunctionalization reactions in synthesis, this review systematically summarizes significant advancements EnT-enabled unsaturated compounds via sigma-bond homolysis over decade. Special emphasis placed on elucidating substrate scopes mechanistic scenarios. Additionally, discusses versatile applications methodologies addresses current challenges opportunities within evolving research field. This structured into six main categories based different types sigma-bonds undergoing homolysis. These include transformations mediated 1) N–O bond oxime esters other N,O-radical precursors; 2) N–S N-sulfonyl imines N,S-radical 3) chalcogen–chalcogen disulfides oxy/thio/selenosulfonates; 4) C–S tri/difluoromethylated sulfinates, acetylenic triflones, arylsulfonium salts; 5) C–X (X = halogen) halides; 6) acceptors. Through providing theoretical backgrounds along comprehensive overview currently employed acceptors, photosensitizers, contemporary EnT-induced compounds, aims serve an invaluable resource future innovations rapidly

Language: Английский

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Shining Fresh Light on Complex Photoredox Mechanisms through Isolation of Intermediate Radical Anions

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(14), P. 9392 - 9403

Published: June 30, 2023

Photoredox catalysis (PRC) has gained enormous and wide-ranging interest in recent years but also been subject to significant mechanistic uncertainty, even controversy. To provide a method by which the missing understanding can begin be filled in, we demonstrate herein that it is possible isolate as authentic materials one-electron reduction products of representative PRC catalysts (PCs). Specifically, KC8 both 9,10-dicyanoanthracene naphthalene monoamide derivative presence cryptand provides convenient access corresponding [K(crypt)+][PC·-] salts clean fully characterized techniques including EPR XRD. Because PC·- states are key intermediates reactions, such isolation allows for highly controlled study these anions' specific reactivity hence their roles. As demonstration this principle, show used conveniently interrogate mechanisms recent, high-profile "conPET" "e-PRC" currently acute Using very simple experiments, able striking insights into reactions' underlying observe surprising levels hidden complexity would otherwise have challenging identify emphasize care control needed when interrogating interpreting mechanisms. These studies foundation far broader range questions around conPET, e-PRC, other reaction future, using same strategy isolation.

Language: Английский

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Photocatalyst‐ and Transition‐Metal‐Free Light‐Induced Formation of Carbon‐Chalcogen Bonds

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 366(2), P. 168 - 182

Published: Dec. 16, 2023

Abstract Photoinduced chemical transformations have become a promising aspect of organic synthesis. This review focuses on the recent advancements in harnessing photoinduced processes for formation carbon‐chalcogen (C−O, C−S, C−Se, and C−Te) bonds under catalyst‐free conditions. These pathways typically involve either radical mechanism or creation electron‐donor‐acceptor (EDA) complexes. The explores intricacies underlying mechanisms, discusses limitations, evaluates applicability various methodologies this field. Notably, photocatalyst transition metal‐free photochemical reactions offer effective alternatives to enhance sustainability research area.

Language: Английский

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Emerging Activation Modes and Techniques in Visible-Light-Photocatalyzed Organic Synthesis

Synthesis, Journal Year: 2022, Volume and Issue: 55(02), P. 193 - 231

Published: Sept. 16, 2022

Abstract Visible light photocatalysis has evolved into a promising mild and sustainable strategy to access radicals. This field unlocks formerly challenging or even previously inaccessible organic transformations. In this review, an overview of some lesser-known modes photochemical activation molecules several emerging techniques within the versatile visible are discussed. These illustrated by selected photocatalytic reactions, with particular attention given reaction mechanism. 1 Introduction 2 Advanced Photoactivation Modes 2.1 Photoinduced Hydrogen-Atom Transfer 2.2 Proton-Coupled Electron 2.3 Donor-Acceptor Organic Substrates 2.4 Excited-State Transition Metal Catalysis 3 Emerging Techniques 3.1 Dual 3.2 Excited Radical Ion Photocatalysis 3.3 Upconversion Strategies Other Two-Photon Mechanisms 3.4 Red Near-Infrared 4 Conclusions Outlook

Language: Английский

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Catalyst-Free Photoinduced C–C Bond Formations

Synthesis, Journal Year: 2023, Volume and Issue: 55(10), P. 1467 - 1486

Published: Feb. 27, 2023

Abstract Use of sustainable energy sources in synthetic organic chemistry has become one the most popular research topics due to environmental pollution and global warming. In this review, we discuss photocatalyst-free transition-metal-free light-induced reactions for construction carbon–carbon (C–C) bonds. The reaction systems discussed here are C–C bond formation via carbene intermediates, radical miscellaneous cyclization. 1 Introduction 2 Bond Formation Carbene Intermediates 3 Radical 4 Miscellaneous Cyclization 5 Conclusion

Language: Английский

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Sustainable Synthesis through Catalyst‐Free Photoinduced Cascaded Bond Formation

Chemistry - An Asian Journal, Journal Year: 2024, Volume and Issue: 19(14)

Published: May 8, 2024

The beginning of photochemical reactions revolutionized synthetic chemistry through sustainable practices. This review explores cutting-edge developments in leveraging light-induced processes for generating cascaded C-C and C-hetero bonds without catalysts. Significantly, catalyst-free photoinduced methodologies have garnered considerable attention, especially the creation varied heterocyclic frameworks drug design synthesis natural products. article delves into underlying mechanisms, addresses limitations, evaluates various methodologies, emphasizing potential photocatalyst transition metal-free to enhance sustainability. Divided two sections, it covers recent strides C-heteroatom multiple bond formation reactions.

Language: Английский

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Hydrosulfonylation of Unactivated Alkenes Involving Sulfonyl Radical Generation via Photocatalytic Activation of Symmetrical Disulfones by an Energy Transfer Mimicry

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(16), P. 12282 - 12296

Published: Aug. 2, 2024

A visible-light-photocatalyzed hydrosulfonylation of unactivated alkenes with symmetrical disulfones using 2,4,6-triisopropylthiophenol as a hydrogen atom donor (H-D) has been developed. Generation two sulfonyl radicals from via activation visible light photocatalysis is involved. Mechanistic studies rule out that are generated disulfone an energy transfer mechanism previously found for lower oxidation state sulfur–sulfur-based reactants (i.e., thiosulfonates and disulfides). Instead, mimic process occurs. This involves photoinduced electron (PET) oxidative quenching the excited photocatalyst (*PC) disulfone, which generates radical sulfinate byproduct, followed by reduction oxidized (PC•+) this byproduct (SET) generating second (PC). The reaction can be performed in dimethyl carbonate at room temperature, features broad functional group compatibility, allows easy recycling disulfide provided 2,4,6-trisubstituted thiophenol used H-D. compared state-of-the-art green metrics.

Language: Английский

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Recent developments in optical aptamer sensors for pesticide residues detectio

Applied Spectroscopy Reviews, Journal Year: 2024, Volume and Issue: 59(9), P. 1147 - 1182

Published: Feb. 1, 2024

Pesticide residues seriously impact food safety and environmental protection. Consequently, there is a pressing demand for the development of dependable efficient methods pesticide detection. In recent years, optical aptamer sensors have emerged as highly sensitive fast-response sensing platforms These developed rely on selectivity sensitivity nucleic acid to specifically interact with target pesticide, resulting in an observable signal response. Various such fluorescence, colorimetry, surface-enhanced Raman scattering (SERS) methods, chemiluminescence (CL) been effectively employed accurate rapid detection pesticides, encompassing range types including insecticides, fungicides, herbicides. offer several advantages quick response times, high sensitivity, user-friendly operation, enabling real-time monitoring. This paper provides comprehensive review advancements application residue assay overarching goal furnishing invaluable reference point forthcoming research realm swift

Language: Английский

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Development of SF₆ as a Formal Electrophilic Fluorinating Reagent for Photocatalyzed Oxidative Fluorination of Phosphine Oxides

Organic Letters, Journal Year: 2024, Volume and Issue: 26(27), P. 5776 - 5781

Published: June 27, 2024

Organophosphorus–fluorine compounds are of significant utility across biology, pharmacy, and chemical synthesis. Here, we introduce a photocatalyzed oxidative-fluorination approach employing SF6 as formal electrophilic fluorinating reagent. It offers an innovative pathway to forge P(O)–F bonds. Notably, sulfur hexafluoride plays dual role both the oxidant reagent under mild conditions in this transformation. Meanwhile, method contributes environmental sustainability by consuming notorious greenhouse gas, underscoring ecological benefits our approach.

Language: Английский

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Recent advances of 3DPAFIPN in photoredox catalysis

Tetrahedron, Journal Year: 2024, Volume and Issue: 163, P. 134138 - 134138

Published: Aug. 1, 2024

Language: Английский

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