Energy transfer photocatalysis: exciting modes of reactivity

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1068 - 1089

Published: Jan. 1, 2024

Leveraging light energy to expose the ‘dark’ reactive states describes whole essence of triplet–triplet transfer. This offers an impressive opportunity conduct a multitude diverse reactions and access sought-after molecular motifs.

Language: Английский

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EnT-Mediated N–S Bond Homolysis of a Bifunctional Reagent Leading to Aliphatic Sulfonyl Fluorides

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(4), P. 2364 - 2374

Published: Jan. 18, 2023

Sulfur(VI) fluoride exchange (SuFEx) gives rise to a plethora of high-valent sulfur linkages; however, the availability (aliphatic) sulfonyl manifolds lag behind, owing limited sources introducing SO2F moiety via classical two-electron approach. Recently, radical-based methodologies have emerged as complementary strategy increase diversity accessible click partners. In this work, synthesis bench-stable sulfamoyl reagent is presented, which may undergo sigma-bond homolysis upon visible-light-induced sensitization form protected β-amino fluorides from alkene feedstocks. Notably, offers an appealing access various building blocks for peptido fluorides, relevant in medicinal chemistry context, well intriguing entry β-ammonium sulfonates and β-sultams, alkenes. Densely functionalized 1,3-sultones were obtained by employing allyl alcohols substrates. Surprisingly, chloride-derived β-imino underwent S-O bond formation ring closure yield rigid cyclopropyl sulfonate ester under SuFEx conditions. Furthermore, engaging thiol-based hydrogen atom donor reaction, reactivity same can be tuned toward direct aliphatic fluorides. Mechanistic experiments indicate energy transfer (EnT)-mediated process. The transient radical adds product occurs either radical-radical coupling or (HAT), respectively.

Language: Английский

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Metal-Free Amino(hetero)arylation and Aminosulfonylation of Alkenes Enabled by Photoinduced Energy Transfer

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(30), P. 16630 - 16641

Published: July 24, 2023

β-(Hetero)arylethylamines are privileged structural motifs found in many high-value organic molecules, including pharmaceuticals and natural products. To construct these important molecular skeletons, previous methods mainly achieved by amino(hetero)arylation reaction with the aid of transition metals preactivated substrates. Herein, we report a metal-free photoinduced intermolecular for single-step installation both (hetero)aryl iminyl groups across alkenes an efficient regioselective manner. This method shows broad scope (up to 124 examples) excellent tolerance various olefins─from simplest ethylene complex multisubstituted can all participate reaction. Furthermore, aminosulfonylation be also conducted presence sodium bisulfite as SO2 source.

Language: Английский

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γ-Amino Alcohols via Energy Transfer Enabled Brook Rearrangement

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(15), P. 10899 - 10907

Published: April 3, 2024

In the long-standing quest to synthesize fundamental building blocks with key functional group motifs, photochemistry in recent past has comprehensively established its attractiveness. Amino alcohols are not only functionally diverse but ubiquitous biologically active realm of compounds. We developed bench-stable bifunctional reagents that could then access sparsely reported γ-amino directly from feedstock alkenes through energy transfer (EnT) photocatalysis. A designed 1,3-linkage across is made possible by intervention a radical Brook rearrangement takes place downstream EnT-mediated homolysis our reagent(s). combination experimental mechanistic investigations and detailed computational studies (DFT) indicates chain propagated reaction pathway.

Language: Английский

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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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Photoredox-Catalyzed Alkene Acylesterification with Acyloxime Esters via C–C and Tertiary C–O Bond Formation

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 7, 2025

We describe an efficient acyl esterification method for alkenes utilizing acyloxime esters as bifunctional reagents featuring radical acylation and congested C–O bond formation. This approach is characterized by mild photoredox conditions, high step atom economy, a broad substrate scope, excellent regioselectivity. A variety of valuable α-acyl hindered alcohol esters, including those obtained via gram-scale synthesis late-stage functionalization pharmaceutical molecules, were presented, demonstrating its synthetic potential practicability.

Language: Английский

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Highly Selective Radical Relay 1,4-Oxyimination of Two Electronically Differentiated Olefins

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(47), P. 21664 - 21673

Published: Nov. 16, 2022

Radical addition reactions of olefins have emerged as an attractive tool for the rapid assembly complex structures, and plentiful applications in organic synthesis, however, such are often limited to polymerization or 1,2-difunctionalization. Herein, we disclose unprecedented radical relay 1,4-oxyimination two electronically differentiated with a class bifunctional oxime carbonate reagents via energy transfer strategy. The protocol is highly chemo- regioselective, three different chemical bonds (C-O, C-C, C-N bonds) were formed single operation orchestrated manner. Notably, this reaction provides access large variety structurally diverse products, obtained products could be easily converted into valuable biologically relevant δ-hydroxyl-α-amino acids. With combination experimental theoretical methods, mechanism has been investigated. Theoretical calculations reveal that chain might operate reaction.

Language: Английский

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Metal-Free Photoinduced Acylboration of [1.1.1]Propellane via Energy Transfer Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(14), P. 9542 - 9549

Published: July 5, 2023

Highly strained 1,3-disubstituted bicyclo[1.1.1]pentanes (BCPs) have been established as bioisosteres of para-disubstituted benzene because they impart valuable pharmacokinetic properties. Herein, we demonstrate an energy transfer-mediated protocol for acylboration [1.1.1]propellanes that allows the direct construction various carbonyl species, such carbamoyl-, carboxyl-, and acyl-, in tandem with synthetically versatile pinacol boronate (Bpin) groups onto BCP substructure under simple reaction conditions. Moreover, drug-like molecules containing boronates are further submitted to late-stage functionalization events. Several important transformations Bpin functional group boronates, including photoinduced cross-coupling reactions BCP-BF3K, derived from BCP-Bpin, were successfully performed showcase synthetic utility. Additionally, diverse elaborate mechanistic investigations provide insights, a plausible mechanism is proposed.

Language: Английский

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Metal-free photosensitized radical relay 1,4-carboimination across two distinct olefins

Chemical Science, Journal Year: 2023, Volume and Issue: 14(9), P. 2447 - 2454

Published: Jan. 1, 2023

Intermolecular carboamination of olefins offers a powerful platform for the rapid construction structurally complex amines from abundant feedstocks. However, these reactions often require transition-metal catalysis, and are mainly limited to 1,2-carboamination. Herein, we report novel radical relay 1,4-carboimination across two distinct with alkyl carboxylic acid-derived bifunctional oxime esters

Language: Английский

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1,2‐Difunctionalization of Acetylene Enabled by Light

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(16)

Published: Feb. 27, 2023

Although the direct conversion of gaseous acetylene into value-added liquid commodity chemicals is becoming increasingly attractive, majority established methodologies are focused on cross-coupling, hydro-functionalization, and polymerization. Herein, we describe a 1,2-difunctionalization method that inserts directly readily available bifunctional reagents. This provides access to diverse C2-linked 1,2-bis-heteroatom products in high regio- stereoselectivity along with opening up previously unexplored synthetic directions. In addition, demonstrate this method's potential by converting obtained functionalized molecules chiral sulfoxide-containing bidentate ligands. Using combination experimental theoretical methods, mechanism for insertion reaction was investigated.

Language: Английский

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