Rhodium‐Catalyzed Asymmetric Macrocyclization towards Crown Ethers Using Hydroamination of Bis(allenes)

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(14)

Опубликована: Фев. 7, 2024

Abstract Enantiomerically enriched crown ethers (CE) exhibit strong asymmetric induction in phase transfer catalysis, supramolecular catalysis and molecular recognition processes. Traditional methods have often been used to access these valuable compounds, which limit their diversity consequently applicability. Herein, a practical catalytic method is described for the gram scale synthesis of class chiral CEs (aza‐crown ethers; ACEs) using Rh‐catalyzed hydroamination bis(allenes) with diamines. Using this approach, wide range vinyl functionalized ring sizes ranging from 12 36 successfully prepared high yields up 92 %, dr >20 : 1 er >99 1. These substituted allow further diversification giving facile various CE derivatives as well three‐dimensional analogues ring‐closing metathesis. Some themselves display potential use catalysis.

Язык: Английский

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Photoredox and Cobalt-Catalyzed Markovnikov-Selective Radical Hydroamination of Unactivated Alkenes with Anilines

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 26, 2025

The intermolecular hydroamination of unactivated alkenes with simple amines continues to be an attractive and challenging undertaking in organic synthesis. current state-of-the-art strategies for photocatalyzed usually commence the formation a C–N bond, thereby delivering exclusively anti-Markovnikov products. We herein reported facile mild Markovnikov anilines through photoredox cobalt-catalyzed hydrogen atom transfer followed by radical-polar crossover nucleophilic amination process. reaction features wide substrate scope, good functional group tolerance, excellent yields. Application this late-stage functionalization relatively complex natural products bioactive molecules further increases utility developed methodology.

Язык: Английский

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Photoredox Catalysis

Elsevier eBooks, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Язык: Английский

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Achieving High-Efficient Carbon Radical-Mediated Cross-Coupling Reaction by Confined Radical Microenvironment in Metal-Organic Framework

Chemical Science, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

It has been well-demonstrated that the combination of photosensitive (PS), hydrogen atom transfer (HAT) and single electron (SET) processes can achieve efficient radical-mediated organic synthesis, but such reaction systems are usually homogeneous, requiring additional HAT agents only activate one substrate. Here, we constructed two crystalline porous materials, Zr/Hf-NDI, which possess excellent light absorbing capacity a confined radical microenvironment, making them able to integrate PS, HAT, SET simultaneously substrates. Thus, as heterogeneous photocatalysts, they exhibited catalytic performance for carbon cross-coupling between alcohols o-phenylenediamine (OPD) synthesize benzimidazoles (yield > 99%). More importantly, displayed very good substrate compatibility, especially OPD substrates with electron-withdrawing groups, even surpassing those noble metal catalysts. In situ characterizations combined theoretical calculations showed high activity these catalysts arose from: (i) metal-oxo clusters NDI˙- ligands form bonding traction activation alcohol substrate, thus facilitate it generate key intermediate α-carbon through process; (ii) acting an donor, forms strong D-A interaction NDI ligand activates itself into radicals OPD˙+, respectively, via process, further promoting reaction. To best our knowledge, this is performing catalyst photocatalytic radical-induced benzimidazole synthesis.

Язык: Английский

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Cooperative Organosulfur/Photoredox Catalysis Enables Radical-Polar Crossover C(sp³)–N Coupling via Inner-Sphere Electron Shuttling

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

Опубликована: Июнь 2, 2025

Radical-polar crossover (RPC) is a valuable mechanistic tool for revitalizing traditional radical and polar chemistries by integrating them. However, transitioning from to pathways across multiple redox events requires precise potential matching between the reaction components (catalysts substrates), which inherently limits scope of these transformations. Here, we present cooperative catalytic platform that diverts key RPC mechanism outer-sphere inner-sphere manifolds, enabling C(sp3)-N coupling active esters with otherwise oxidizable (hetero)arylamines. The success identification organosulfur catalyst capable selectively shuttling electrons photocatalyst incipient in preference competing arylamine oxidation. Experimental computational studies reveal tailored plays crucial role steering post-radical generation steps guide desired trajectory bond formation. This method displays good functional group compatibility chemoselectivity, providing an efficient route functionally rich secondary tertiary arylamines. virtue this was further demonstrated late-stage applications synthesizing medically relevant nitrogen-containing compounds.

Язык: Английский

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Photoredox catalyzed hydroazolylation of alkenes via phosphoranyl radicals

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(10), С. 2839 - 2844

Опубликована: Янв. 1, 2024

A general protocol for the hydroazolylation of alkenes with N -hydroxyl azoles is reported. These reactions proceed via a phosphoranyl radical, followed by radical coupling resulting azole to alkene radical.

Язык: Английский

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Photoredox‐Catalyzed Metal‐Free Regio‐ & Stereoselective C(sp²)–H Amination of Enamides with N‐Aminopyridium Salts

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(18), С. 2235 - 2242

Опубликована: Май 11, 2024

Comprehensive Summary A visible‐light‐induced photoredox‐catalyzed regioselective and stereoselective C(sp 2 )–H amination of enamides with bench‐stable easily accessible N ‐aminopyridium salts is developed, affording synthetically biologically prominent vicinal 1,2‐diamine scaffolds broad substrate scope excellent functional group compatibility. The transformation proceeded through a radical pathway involving the Giese addition relatively electrophilic ‐centered sulfonamidyl species to nucleophilic β‐olefinic position followed by ensuing single electron oxidation β‐H elimination, delivering geometrically‐defined Z ‐configured β‐sulfonamidylated enamides. operational simplicity, environmental friendliness cost efficiency this methodology allowed it pave new avenue enrich arsenal crucial functionalized their related derivatives.

Язык: Английский

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Cooperative Phosphine-Photoredox Catalysis Enables N–H Activation of Azoles for Intermolecular Olefin Hydroamination

Опубликована: Апрель 30, 2024

Catalytic intermolecular olefin hydroamination is an enabling synthetic strategy that offers direct and atom-economical access to a variety of nitrogen-containing compounds from abundant feedstocks. However, despite numerous advances in catalyst design reaction development, N–H azoles with unactivated olefins remains unsolved problem synthesis. We report dual phosphine photoredox catalytic protocol for the structurally diverse medicinally relevant olefins. Hydroamination proceeds high anti-Markovnikov regioselectivity N-site selectivity. The mild conditions functional group tolerance permit rapid construction molecular complexity late-stage functionalization bioactive compounds. bond activation proposed proceed via polar addition heterocycle radical cation, followed by P–N α-scission phosphoranyl intermediate. Reac-tivity selectivity are classified BDFE nitrogen-centered (NCR) spin density, respectively, which can serve as useful predictive aid extending unseen azoles.

Язык: Английский

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Bidirectional Electron Transfer Strategies for Anti-Markovnikov Olefin Aminofunctionalization via Arylamine Radicals

ACS Catalysis, Год журнала: 2024, Номер 14(17), С. 13156 - 13162

Опубликована: Авг. 17, 2024

Arylamines are common structural motifs in pharmaceuticals, natural products, and materials precursors. While olefin aminofunctionalization chemistry can provide entry to arylamines, classical polar reactions typically afford Markovnikov products. Nitrogen-centered radical intermediates the opportunity access anti-Markovnikov selectivity; however, arylamination is unknown large part due lack of arylamine Here, we introduce bidirectional electron transfer processes generate from N-pyridinium arylamines: Single-electron oxidation provides radicals that engage aminopyridylation; single-electron reduction unveils aminofunctionalization. The development redox complements design principles for precursors, which function via a single manifold. Demonstration both oxidative reductive mechanisms N-aminopyridinium precursor complementary methods rapidly construct diversify scaffolds readily available

Язык: Английский

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Generation of alkene radical cation for thioxanthone-TfOH complex-catalyzed intramolecular cyclization using a photoredox catalysis strategy

Journal of Catalysis, Год журнала: 2024, Номер unknown, С. 115817 - 115817

Опубликована: Окт. 1, 2024

Язык: Английский

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