Access to Benzyl Oxindoles via Electron Donor‐Acceptor Complex Photoactivation Using Thianthrenium Salts and Potassium Carbonate

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(11), С. 2587 - 2595

Опубликована: Апрель 19, 2024

Abstract A photochemical synthesis of biologically relevant benzyl oxindoles is presented via electron‐donor acceptor (EDA) complex strategy. This exogenous photocatalyst‐free method describes the formation a new electron donor‐acceptor based on potassium carbonate and thianthrenium salts for C( sp 2 )−C( 3 ) bond formation. transition‐metal free reaction allows rapid increase in molecular complexity chemical space, tolerating different functional groups as well sophisticated biomolecules. The scalability sustainability this highlighted by an important waste recovery protocol. Mechanistic investigations support EDA that induces radical chain, applicability showcased straightforward derivatization reactions.

Язык: Английский

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Synthesis of Sulfur-Containing Trisubstituted Imidazoles by One-Pot, Multicomponent Reaction via Electron Donor–Acceptor Complex Photoactivation

Organic Letters, Год журнала: 2024, Номер 26(17), С. 3541 - 3546

Опубликована: Апрель 24, 2024

Rapid and efficient construction of multifunctionalized skeletons through a one-pot multicompound domino reaction has been recognized as simple practical strategy. Herein, visible-light-enabled three-component isothiocyanates, isocyanides, thianthrenium salt-functionalized arenes is presented, which affords facile approach to sulfur-containing trisubstituted imidazoles in good yields with broad substrate scope excellent functional group tolerance. The byproduct thianthrene recovered quantity, thereby ultimately reducing the production chemical waste. developed methodology potential value for discovery development thioimidazole-based drugs.

Язык: Английский

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Arylcyanation of Styrenes by Photoactive Electron Donor–Acceptor Complexes/Copper Catalysis

Organic Letters, Год журнала: 2024, Номер 26(37), С. 7949 - 7955

Опубликована: Сен. 11, 2024

A novel electron donor-acceptor (EDA) complex/copper catalysis model has been proposed for the construction of 2,3-diarylpropionitriles under visible light conditions. The developed protocol proceeds via intermolecular charge transfer between photoactive EDA complex dibutamine (DBA), aryl thianthrenium salts, and trimethylsilyl cyanide (TMSCN), followed by a copper catalytic cycle. UV-vis absorption measurements confirm participation complexes as reactive intermediates. This three-component process smoothly in presence pharmaceutically relevant core structures sensitive functional groups, which offers possibility precise editing drug molecules with important scaffolds.

Язык: Английский

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Thianthrenium-Enabled Chromium-Catalyzed Deuterated Alkyl Addition to Aldehydes via a Photoactive Electron Donor–Acceptor Complex

Organic Letters, Год журнала: 2025, Номер 27(5), С. 1112 - 1117

Опубликована: Янв. 23, 2025

The Nozaki-Hiyama-Kishi reaction offers effective and reliable strategies for the preparation of alcohols via carbon-carbon bond formation. Typical methods usually require stoichiometric amounts chromium salts, co-transition metals, auxiliary reagents, which limits their practical application in industrial chemistry. To mitigate these limitations, substantial efforts have been made to develop chromium-catalytic approaches. However, an excess metal reductants or expensive photocatalysts played essential roles during catalytic cycles. Here, we present a photoactive electron donor-acceptor (EDA) complex-induced chromium-catalyzed route, accomplishing alkyl addition aldehydes without requirement photocatalysts. Furthermore, on basis pH-dependent site-selective hydrogen isotope exchange thianthrenium range β-deuterated secondary could be prepared with high efficiency excellent deuterium incorporation. Mechanistic studies revealed that photoinduced intramolecular single-electron transfer EDA complex happened provide radicals are captured by Cr(II) species facilitate subsequent Meanwhile, excited Hantzsch ester act as terminal reductant turnover catalyst.

Язык: Английский

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Dual Copper/Photoredox Catalysis for Radical-Mediated Arylation and Alkylation of Sulfenamides

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 4007 - 4016

Опубликована: Фев. 20, 2025

Язык: Английский

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Synergistic Photoenzymatic Anti-Markovnikov Hydroarylation of Olefins via Heteroaryl Radical Intermediates

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 16, 2025

Heteroaromatic alkylations are indispensable reactions for synthesizing biologically active molecules. The anti-Markovnikov hydroarylation of olefins using heteroaryl halides furnishes the product as a single regioisomer; however, catalytic variants ineffective at controlling stereochemical outcome these reactions. Here, we report synergistic photoenzymatic flavin-dependent "ene"-reductases with ruthenium photoredox catalysts. Enzyme homologues were identified, which provide access to both enantiomers in greater than 80% yield up 99:1 er. This method is effective styrenyl- and unactivated alkenes, highlighting generality this approach. highest yielding system involves carboxylated photocatalyst increased affinity enzyme. work expands types radical intermediates that enzymes can use stereoselective intermolecular coupling

Язык: Английский

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Visible Light‐promoted C(sp³)‐H α‐Carbamoylation of Cyclic Ethers with Isocyanides

Chemistry - A European Journal, Год журнала: 2024, Номер 30(48)

Опубликована: Июнь 14, 2024

Abstract A protocol exploiting isocyanides as carbamoylating agents for the α‐C( sp 3 )‐H functionalization of cyclic ethers has been optimized via a combined visible light‐driven hydrogen atom transfer/Lewis acid‐catalyzed approach. The isocyanide substrate scope revealed an exquisite functional group compatibility (18 examples, with yields up to 99 %). Both radical and polar trapping, kinetic isotopic effect real‐time NMR studies support mechanistic hypothesis provide insightful details design new chemical processes involving generation oxocarbenium ions.

Язык: Английский

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Photoinduced Cu(II)‐Mediated Decarboxylative Thianthrenation of Aryl and Heteroaryl Carboxylic Acids

Angewandte Chemie International Edition, Год журнала: 2024, Номер unknown

Опубликована: Июль 16, 2024

Given that (hetero)aryl carboxylic acids are inexpensive materials available in a great variety from commercial and natural resources or synthesis, the strategies enabling their use as starting for preparing fine chemicals highly sought after. Here we report photoinduced Cu(II)-mediated protocol converting into thianthrenium salts, high value-added building blocks can undergo various subsequent transformations, creating an attractive two-step pathway divergent functionalization of these ubiquitous materials. The excellent compatibility method is shown by broad range sterically electronically varied including derivatives pharmaceuticals, such ataluren, celecoxib, flavoxate, probenecid, repaglinide, tamibarotene. syntheses 13 C-labeled probenecid bioisosteres ataluren well unconventional modifications celecoxib illustrate synthetic potential strategy. Mechanistic studies line with reaction occurring through ligand-to-metal charge transfer (LMCT) Cu(II)-arylcarboxylates, radical decarboxylative carbometallation to form arylcopper(II) intermediates turn react thianthrene product. Noteworthy, susceptibility aryl salts photodegradation overcome Cu(I)-driven salvage loop, which continuously intercepts transiently formed radicals regenerates products.

Язык: Английский

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Overcoming Copper Reduction Limitation in Asymmetric Substitution: Aryl-Radical-Enabled Enantioconvergent Cyanation of Alkyl Iodides

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(46), С. 31982 - 31991

Опубликована: Ноя. 6, 2024

Cu-catalyzed enantioconvergent cross-coupling of alkyl halides has emerged as a powerful strategy for synthesizing enantioenriched molecules. However, this approach is intrinsically limited by the weak reducing power copper(I) species, which restricts scope compatible nucleophiles and necessitates extensive ligand optimization or use complex chiral scaffolds. To overcome these challenges, we introduce an aryl-radical-enabled that decouples halide activation step from Cu center. We demonstrate merging iodine abstraction with asymmetric radical functionalization enables conversion racemic α-iodoamides to nitrile products good yield enantioselectivity. The rational design ligands identified new class carboxamide-containing BOX ligands. Mechanistic studies support pathway unique hydrogen-bonding ability in newly designed This substitution reaction potential significantly expand reactions.

Язык: Английский

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Photoinduced Cu(II)‐Mediated Decarboxylative Thianthrenation of Aryl and Heteroaryl Carboxylic Acids

Angewandte Chemie, Год журнала: 2024, Номер 136(42)

Опубликована: Июль 16, 2024

Abstract Given that (hetero)aryl carboxylic acids are inexpensive materials available in a great variety from commercial and natural resources or synthesis, the strategies enabling their use as starting for preparing fine chemicals highly sought after. Here we report photoinduced Cu(II)‐mediated protocol converting into thianthrenium salts, high value‐added building blocks can undergo various subsequent transformations, creating an attractive two‐step pathway divergent functionalization of these ubiquitous materials. The excellent compatibility method is shown by broad range sterically electronically varied including derivatives pharmaceuticals, such ataluren, celecoxib, flavoxate, probenecid, repaglinide, tamibarotene. syntheses 13 C‐labeled probenecid bioisosteres ataluren well unconventional modifications celecoxib illustrate synthetic potential strategy. Mechanistic studies line with reaction occurring through ligand‐to‐metal charge transfer (LMCT) Cu(II)‐arylcarboxylates, radical decarboxylative carbometallation to form arylcopper(II) intermediates turn react thianthrene product. Noteworthy, susceptibility aryl salts photodegradation overcome Cu(I)‐driven salvage loop, which continuously intercepts transiently formed radicals regenerates products.

Язык: Английский

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