Scalable decarboxylative trifluoromethylation by ion-shielding heterogeneous photoelectrocatalysis

Science, Год журнала: 2024, Номер 384(6696), С. 670 - 676

Опубликована: Май 9, 2024

Electrochemistry offers a sustainable synthesis route to value-added fine chemicals but is often constrained by competing electron transfer between the electrode and redox-sensitive functionalities distinct from target site. Here, we describe an ion-shielding heterogeneous photoelectrocatalysis strategy impose mass-transfer limitations that invert thermodynamically determined order of transfer. This showcased enable decarboxylative trifluoromethylation sensitive (hetero)arenes using trifluoroacetate, inexpensive yet relatively inert trifluoromethyl group (CF

Язык: Английский

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Catalysis in the Excited State: Bringing Innate Transition Metal Photochemistry into Play

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 4665 - 4680

Опубликована: Март 5, 2025

Transition metal catalysis is an indispensable tool for organic synthesis that has been harnessed, modulated, and perfected many decades by careful selection of centers ligands, giving rise to synthetic methods with unparalleled efficiency chemoselectivity. Recent developments have demonstrated how light irradiation can also be recruited as a powerful dramatically alter the outcome catalytic reactions, providing access innovative pathways remarkable potential. In this context, adoption photochemical conditions mainstream strategy drive reactions unveiled exciting opportunities exploit rich excited-state framework transition metals applications. This Perspective examines advances in application complexes standalone photocatalysts, exploiting innate reactivity their excited states beyond common use photoredox catalysts. An account relevant examples dissected provide discussion on electronic reorganization, orbitals involved, associated different types states. analysis aims practitioners fundamental principles guiding strategies understand, design, apply light-activation homogeneous synthesis.

Язык: Английский

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Bi-Catalyzed Trifluoromethylation of C(sp²)–H Bonds under Light

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(47), С. 25538 - 25544

Опубликована: Ноя. 14, 2023

We disclose a Bi-catalyzed C–H trifluoromethylation of (hetero)arenes using CF3SO2Cl under light irradiation. The catalytic method permits the direct functionalization various heterocycles bearing distinct functional groups. structural and computational studies suggest that process occurs through an open-shell redox manifold at bismuth, comprising three unusual elementary steps for main group element. cycle starts with rapid oxidative addition to low-valent Bi(I) catalyst, followed by light-induced homolysis Bi(III)–O bond generate trifluoromethyl radical upon extrusion SO2, is closed hydrogen-atom transfer Bi(II) intermediate.

Язык: Английский

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Decarboxylative Sulfonylation of Carboxylic Acids under Mild Photomediated Iron Catalysis

Organic Letters, Год журнала: 2024, Номер 26(12), С. 2381 - 2386

Опубликована: Март 15, 2024

Organic sulfones are an important class of chemical compounds widely used in many research fields. The direct decarboxylative sulfonylation carboxylic acids is attractive but challenging, particularly when iron as a metal catalyst. Herein, we describe photoinduced iron-catalytic method for the synthesis directly using via radical-based decarboxylation. This protocol mild, highly efficient, and easy-to-operate. A broad scope carbon electrophiles could be well tolerated. mechanism involving iron-catalyzed decarboxylation, radical transfer, single-electron reduction, nucleophilic attack proposed.

Язык: Английский

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Radical-Mediated Decarboxylative C–C and C–S Couplings of Carboxylic Acids via Iron Photocatalysis

Organic Letters, Год журнала: 2024, Номер 26(5), С. 1110 - 1115

Опубликована: Янв. 26, 2024

Despite the significant success of decarboxylative radical reactions, catalytic systems vary considerably upon different acceptors, requiring renewed case-by-case reaction optimization. Herein, we developed an iron condition that enables highly efficient decarboxylation various carboxylic acids for a range transformations. This operationally simple protocol was amenable to wide array delivering structurally diverse oxime ethers, alkenylation, alkynylation, thiolation, and amidation products in useful excellent yields (>40 examples, up 95% yield).

Язык: Английский

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Iron photocatalysis via Brønsted acid-unlocked ligand-to-metal charge transfer

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

Опубликована: Июль 20, 2024

Abstract Reforming sustainable 3d-metal-based visible light catalytic platforms for inert bulk chemical activation is highly desirable. Herein, we demonstrate the use of a Brønsted acid to unlock robust and practical iron ligand-to-metal charge transfer (LMCT) photocatalysis multifarious haloalkylcarboxylates (C n X m COO − , = F or Cl) produce C radicals. This process enables fluoro-polyhaloalkylation non-activated alkenes by combining easily available Selectfluor as fluorine source. Valuable alkyl fluorides including potential drug molecules can be obtained through this protocol. Mechanistic studies indicate that real light-harvesting species may derive from in situ-assembly Fe 3+ H + acetonitrile solvent, which indeed increases efficiency LMCT between center via hydrogen-bond interactions. We anticipate acid-unlocked platform would an intriguing option execute compounds.

Язык: Английский

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Iron(III) Carbene Complexes with Tunable Excited State Energies for Photoredox and Upconversion

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Апрель 10, 2024

Substituting precious elements in luminophores and photocatalysts by abundant first-row transition metals remains a significant challenge, iron continues to be particularly attractive owing its high natural abundance low cost. Most complexes known date face severe limitations due undesirably efficient deactivation of luminescent photoredox-active excited states. Two new iron(III) with structurally simple chelate ligands enable straightforward tuning ground state properties, contrasting recent examples, which chemical modification had minor impact. Crude samples feature two luminescence bands strongly reminiscent complex, this observation was attributed dual luminescence, but our case, there is clear-cut evidence that the higher-energy stems from an impurity only red photoluminescence doublet ligand-to-metal charge transfer (2LMCT) genuine. Photoinduced oxidative reductive electron reactions methyl viologen 10-methylphenothiazine occur nearly diffusion-limited kinetics. Photocatalytic not previously reported for compound class, particular C–H arylation diazonium salts aerobic hydroxylation boronic acids, were achieved low-energy light excitation. Doublet–triplet energy (DTET) 2LMCT anthracene annihilator permits proof principle triplet–triplet annihilation upconversion based on molecular photosensitizer. These findings are relevant development featuring photophysical photochemical properties competitive noble-metal-based compounds.

Язык: Английский

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Selective Arene Photonitration via Iron-Complex β-Homolysis

JACS Au, Год журнала: 2024, Номер 4(12), С. 4899 - 4909

Опубликована: Ноя. 21, 2024

Nitroaromatics, as an important member and source of nitrogen-containing aromatics, is bringing enormous economic benefits in fields pharmaceuticals, dyes, pesticides, functional materials, fertilizers, explosives. Nonetheless, the notoriously polluting nitration industry, which suffers from excessive discharge fumes waste acids, poor group tolerance, tremendous purification difficulty, renders mild, efficient, environmentally friendly a formidable challenge. Herein, we develop visible-light-driven biocompatible arene C–H strategy with good efficiency regioselectivity, marvelous substrate applicability wide application scale-up synthesis, total late-stage functionalization. A nitryl radical delivered through unusual β-homolysis photoexcited ferric-nitrate complex proposed to be key nitrification reagent this system.

Язык: Английский

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A General Iron‐Catalyzed Decarboxylative Oxygenation of Aliphatic Carboxylic Acids

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(32)

Опубликована: Май 13, 2024

Abstract We report an iron‐catalyzed decarboxylative C(sp 3 )−O bond‐forming reaction under mild, base‐free conditions with visible light irradiation. The transformation uses readily available and structurally diverse carboxylic acids, iron photocatalyst, 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) derivatives as oxygenation reagents. process exhibits a broad scope in acids possessing wide range of stereoelectronic properties functional groups. developed was applied to late‐stage series bio‐active molecules. leverages the ability complexes generate carbon‐centered radicals directly from by photoinduced carboxylate‐to‐iron charge transfer. Kinetic, electrochemical, EPR, UV/Vis, HRMS, DFT studies revealed that TEMPO has triple role reaction: reagent, oxidant turn over Fe‐catalyst, internal base for acid deprotonation. obtained adducts represent versatile synthetic intermediates were further engaged C−C C‐heteroatom reactions using commercial organo‐photocatalysts nucleophilic

Язык: Английский

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Photoinduced difunctionalizations of unactivated olefins enabled by ligand-to-iron charge transfer and functional group migration strategies

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(17), С. 4748 - 4756

Опубликована: Янв. 1, 2024

Difunctionalizations of unactivated olefins with fluoroalkyl carboxylic acids or aldehydes via a radical-mediated functional group migration strategy are herein reported.

Язык: Английский

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