Selective Coupling of 1,2‐Bis‐Boronic Esters at the more Substituted Site through Visible‐Light Activation of Electron Donor–Acceptor Complexes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(18)

Опубликована: Фев. 25, 2022

1,2-Bis-boronic esters are useful synthetic intermediates particularly as the two boronic can be selectively functionalized. Usually, less hindered primary ester reacts, but herein, we report a coupling reaction that enables reversal of this selectivity. This is achieved through formation boronate complex with an electron-rich aryllithium which, in presence electron-deficient aryl nitrile, leads to electron donor-acceptor complex. Following visible-light photoinduced transfer, radical generated which isomerizes more stable secondary before radical-radical arene radical-anion, giving β-aryl products. The reactions proceed under catalyst-free conditions. method also allows stereodivergent cyclic cis-1,2-bis-boronic provide trans-substituted products, complementing selectivity observed Suzuki-Miyaura reaction.

Язык: Английский

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Synthesis of carbinoxamine via α-C(sp³)–H 2-pyridylation of O, S or N-containing compounds enabled by non-D–A-type super organoreductants and sulfoxide- or sulfide HAT reagents

Chemical Science, Год журнала: 2022, Номер 13(37), С. 11246 - 11251

Опубликована: Янв. 1, 2022

We report the discovery of a non-donor–acceptor (D–A) type organic photoreductant CBZ6 and sulfoxide/sulfide synergistically catalyzed general α-C(sp 3 )–H arylation ethers, thioethers amines.

Язык: Английский

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Visible Light‐induced Functionalization of C−H Bonds: Opening of New Avenues in Organic Synthesis

Asian Journal of Organic Chemistry, Год журнала: 2022, Номер 11(6)

Опубликована: Фев. 14, 2022

Abstract In the last three decades, resurgence and astonishing evolution of visible light‐mediated unreactive C−H bond functionalization has led to a sustainable greener approach for introducing various moieties into imperative organic frameworks without need substrate preactivation. Unlike traditional electrophilic or nucleophilic reactions, free radical mechanism photoredox catalysis opens up new routes achieve unprecedented functionalization. this context, single‐electron transfer energy interactions among exogenous photocatalysts, i. e ., TM photocatalysts dye photosensitizers, etc., in their excited state with targeted substrate, thus generates active species, which encompasses further elusive reaction pathways. This review covers distinct generation methods via trigger cleavage through light irradiation. Herein, we provide an overview progress made five years visible‐light‐induced functionalization, may help chemists envision significant chemical transformations molecular complexity.

Язык: Английский

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Regio-Selective C3- and N-Alkylation of Indolines in Water under Air Using Alcohols

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(9), С. 5603 - 5616

Опубликована: Апрель 13, 2022

We disclosed a regio-selective C–H and N–H bond functionalization of indolines using alcohols in water via tandem dehydrogenation N-heterocycles alcohols. A diverse range N- C3-alkylated indolines/indoles were accessed utilizing new cooperative iridium catalyst. The practical applicability this methodology was demonstrated by the preparative-scale synthesis psychoactive drug, N,N-dimethyltryptamine. catalytic cycle is proposed based on several kinetic experiments, series control experiments density functional theory calculations.

Язык: Английский

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Visible-Light-Induced Oxyalkylation of 1,2,4-Triazine-3,5(2H, 4H)-diones with Ethers via Oxidative Cross-Dehydrogenative Coupling

The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(13), С. 8551 - 8561

Опубликована: Июнь 22, 2022

An efficient and convenient method to synthesize 6-oxyalkylated 1,2,4-triazine-3,5(2H, 4H)-diones has been developed via visible-light-induced cross-dehydrogenative coupling reaction between ethers with a wide range of functional group tolerance. The present transformation employs the cheap low-toxic 2-tert-butylanthraquinone as metal-free photocatalyst air green oxidant at room temperature. Moreover, this can also be driven by sunlight clean energy resource. synthetic utility is further demonstrated gram-scale application in preparation key intermediates bioactive molecules.

Язык: Английский

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Catalyst-Free Photoinduced C–C Bond Formations

Synthesis, Год журнала: 2023, Номер 55(10), С. 1467 - 1486

Опубликована: Фев. 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

Язык: Английский

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Electron Donor‐Acceptor (EDA) Complex Enabled C−C Cross‐Coupling Reactions of α‐Amino Radicals

Asian Journal of Organic Chemistry, Год журнала: 2024, Номер 13(6)

Опубликована: Апрель 18, 2024

Abstract Electron‐donor acceptor (EDA) complex has been an integral part of visible‐light photocatalysis and is different from the traditional photoredox catalysis, which requires exogenous photocatalyst, typically a colored compound to initiate photocatalytic cycle. Interestingly, EDA‐complex photochemistry found profound use in activating inert α‐C−H bonds amines. The strategy relied upon formation between donor (amine) (Lewis acid), harvesting light energy perform SET process generate radical cation anion intermediates. then loses activated acidic proton (because SET, acidity α‐proton increases by lowering BDE) form α‐amino radical, participates various C−C coupling cascades. In this review, conceptual approaches for generation radicals their bond‐forming reaction under triggered will be discussed with particular emphasis on mechanism 2018 onwards.

Язык: Английский

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Electron Donor-Acceptor (EDA) Complex-Driven Activation of N-α C—H Bonds

Chinese Journal of Organic Chemistry, Год журнала: 2025, Номер 45(2), С. 559 - 559

Опубликована: Янв. 1, 2025

Язык: Английский

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Photocatalytic α-C(sp³)–H Arylation/Heteroarylation of Amines Enabled by Pyrylium Salt

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 6, 2025

A general photocatalytic α-C(sp3)-H arylation/heteroarylation of amines has been developed. In the presence newly designed DPA-TPT, reaction can operate under mild conditions and produce a diverse array tertiary benzylic in good yields. Additionally, late-stage arylation tetracaine demonstrated practical application this protocol, highlighting its versatility efficiency functionalizing complex molecules.

Язык: Английский

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Towards a More Sustainable Photocatalyzed α‐Arylation of Amines: Green Solvents, Catalyst Recycling and Low Loading

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(2), С. 252 - 262

Опубликована: Янв. 7, 2023

Abstract A more sustainable and efficient protocol for the photocatalytic α‐amino arylation promoted by fac ‐Ir(ppy) 3 was developed. Three noteworthy results were achieved: i) replacement of toxic medium DMA with greener solvents NBP NHP, concurrent improvement process efficiency lowering both amine base amount; ii) development a recycling solvent NHP commercially available costly photocatalyst , achieving environmental economic benefits. This approach to recovery avoids very demanding catalyst structural modifications; iii) in green proved be scalable up 10 mmol limiting reagent, maintaining excellent performance also loading down 0.05 mol%. is first example α‐arylation amines such low amount catalyst. Lastly, versatility this demonstrated extending use another photoredox process. magnified image

Язык: Английский

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