Enantioselective [2π + 2σ] Cycloadditions of Bicyclo[1.1.0]butanes with Vinylazaarenes through Asymmetric Photoredox Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(12), С. 8372 - 8380

Опубликована: Март 18, 2024

Here we present a highly enantioselective [2π + 2σ] photocycloaddition of bicyclo[1.1.0]butanes (BCBs). The reaction uses variety vinylazaarenes as partners and is catalyzed by polycyclic aromatic hydrocarbon (PAH)-containing chiral phosphoric acid bifunctional photosensitizer. A wide array pharmaceutically important bicyclo[2.1.1]hexane (BCH) derivatives have been synthesized with high yields, enantioselectivity, diastereoselectivity. In addition to the diverse 1-ketocarbonyl-3-substituted BCBs, α/β-substituted are compatible such an unprecedented photoredox catalytic pathway, resulting in successful assembly all-carbon quaternary stereocenter or two adjacent tertiary stereocenters on product.

Язык: Английский

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Asymmetric Cross-Coupling of Aldehydes with Diverse Carbonyl or Iminyl Compounds by Photoredox-Mediated Cobalt Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10857 - 10867

Опубликована: Апрель 8, 2024

The asymmetric cross-coupling of unsaturated bonds, hampered by their comparable polarity and reactivity, as well the scarcity efficient catalytic systems capable diastereo- enantiocontrol, presents a significant hurdle in organic synthesis. In this study, we introduce highly adaptable photochemical cobalt catalysis framework that facilitates chemo- stereoselective reductive cross-couplings between common aldehydes with broad array carbonyl iminyl compounds, including N-acylhydrazones, aryl ketones, aldehydes, α-keto esters. Our methodology hinges on synergistic mechanism driven photoredox-induced single-electron reduction subsequent radical–radical coupling, all precisely guided chiral catalyst. Various optically enriched β-amino alcohols unsymmetrical 1,2-diol derivatives (80 examples) have been synthesized good yields (up to 90% yield) high stereoselectivities >20:1 dr, 99% ee). Of particular note, approach accomplishes unattainable transformations disparate partners without reliance any external photosensitizer, thereby further emphasizing its versatility cost-efficiency.

Язык: Английский

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Catalytic Asymmetric Redox‐Neutral [3+2] Photocycloadditions of Cyclopropyl Ketones with Vinylazaarenes Enabled by Consecutive Photoinduced Electron Transfer

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(30)

Опубликована: Апрель 30, 2024

Abstract Consecutive photoinduced electron transfer (ConPET) is a powerful and atom‐economical protocol to overcome the limitations of intrinsic redox potential visible light‐absorbing photosensitizers, thereby considerably improving substrate reaction types. Likely because such an exothermic single‐electron (SET) process usually does not require aid chiral catalysts, resulting in inevitable racemic background reaction, notably, no enantioselective manifolds have been reported. Herein, we report on viability cooperative ConPET hydrogen‐bonding catalysis for [3+2] photocycloaddition cyclopropyl ketones with vinylazaarenes. In addition enabling first use olefins that preferentially interact this platform paves way efficient synthesis pharmaceutically synthetically important cyclopentyl functionalized by azaarenes high yields, ees dr. The robust capacity method can be further highlighted low loading catalyst (1.0 mol %), good compatibility both 2‐azaarene 3‐pyridine‐based olefins, successful concurrent construction three stereocenters cyclopentane rings involving elusive but all‐carbon quaternary.

Язык: Английский

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Enantioselective [2 + 2] Photocycloreversion Enables De Novo Deracemization Synthesis of Cyclobutanes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(32), С. 22840 - 22849

Опубликована: Авг. 2, 2024

While photochemical deracemization significantly enhances atom economy by eliminating the necessity for additional oxidants or reductants, laborious presynthesis of substrates from feedstock chemicals is often required, thereby compromising practicality this method. In study, we propose a novel approach known as de novo synthesis, which involves direct utilization simple undergoing both transformation and reversible transformation. The efficient enantiocontrol chiral catalysts in latter process establishes an effective platform deracemization. This alternative practical to address challenges asymmetric photocatalysis has been successfully demonstrated photosensitized synthesis azaarene-functionalized cyclobutanes featuring three stereocenters, including all-carbon quaternary center. By exclusively employing suitable catalyst enable kinetically controlled [2 + 2] photocycloreversion, pave creative path toward achieving more cost-effective

Язык: Английский

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Catalytic asymmetric photocycloaddition reactions mediated by enantioselective radical approaches

Chemical Society Reviews, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

The use of olefins in the construction cyclic compounds represents a powerful strategy for advancing pharmaceutical industry.

Язык: Английский

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Asymmetric Photoredox Catalytic Minisci-Type Reactions of α-Bromide Amides

Organic Letters, Год журнала: 2025, Номер 27(5), С. 1244 - 1249

Опубликована: Янв. 23, 2025

An asymmetric photoredox catalytic Minisci-type reaction between α-bromide amides and imine-containing azaarenes has been successfully developed. This catalyst system employs a chiral phosphoric acid alongside 3DPAFIPN as photosensitizer. The produces diverse array of valuable amides, featuring azaarene-substituted tertiary carbon stereocenters at the β-position, in high yields (up to 85%) good excellent enantioselectivities >99% enantiomeric excess (ee)). Importantly, this work marks first example radical addition simple utilizing radicals functionalized with electron-withdrawing carbonyl groups, which are conventionally considered unfavorable for such transformations, especially an enantioselective manner.

Язык: Английский

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Catalytic asymmetric [4 + 2] dearomative photocycloadditions of anthracene and its derivatives with alkenylazaarenes

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

Опубликована: Май 29, 2024

Abstract Photocatalysis through energy transfer has been investigated for the facilitation of [4 + 2] cycloaddition reactions. However, high reactivity radical species poses a challenging obstacle to achieving enantiocontrol with chiral catalysts, as no enantioselective examples have reported thus far. Here, we present development catalytic asymmetric dearomative photocycloaddition involving anthracene and its derivatives alkenylazaarenes. This accomplishment is achieved by utilizing cooperative photosensitizer Brønsted acid catalysis platform. Importantly, this process enables activation substrates from triplet DPZ, thereby initiating precise stereoselective sequential transformation. The significance our work highlighted synthesis diverse range pharmaceutical valuable cycloadducts incorporating attractive azaarenes, all obtained yields, ees, drs. broad substrate scope further underscored successful construction all-carbon quaternary stereocenters adjacent stereocenters.

Язык: Английский

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Chemodivergent Synthesis of Benzofurans and 2,3‐Dihydrobenzofurans via Tandem Oxidative Annulation of Enaminones and Salicylaldehydes

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(15), С. 1727 - 1733

Опубликована: Март 26, 2024

Comprehensive Summary Chemodivergent synthesis of benzofurans and 2,3‐dihydrobenzofurans has been realized. Under a reaction system consisting DBDMH K 2 CO 3 as promotors, controlled conditions enabled the formation two sets valuable heterocycles from tandem transformation enaminones salicylaldehydes. The key to success was identification parameters, in which imine intermediate formed by transient halogenation coupling substitution processes underwent either aldol condensation/annulation or hydrolysis/aldol condensation. additives NH 4 Cl Fe (SO ) unique selectivity this reaction. A broad substrate scope salicylaldehydes employed reaction, demonstrating excellent functional group tolerance versatility.

Язык: Английский

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Lead-halide perovskite quantum dots embedded in mesoporous silica as heterogeneous photocatalysts combined with organocatalysts for asymmetric catalysis

Green Chemistry, Год журнала: 2024, Номер 26(10), С. 6068 - 6077

Опубликована: Янв. 1, 2024

CsPbBr 3 quantum dots embedded in KIT-6 to form silica-shell-protected heterogeneous photocatalysts, which were further combined with chiral organocatalysts forming dual-catalysts explore the activity and stereoselectivity asymmetric catalysis.

Язык: Английский

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Chiral Primary Amine-Catalyzed Asymmetric Photochemical Reactions of Pyridotriazoles with Boronic Acids to Access Triarylmethanes

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

Опубликована: Янв. 29, 2025

Imine-containing azaarene-based triarylmethanes are vital molecular motifs that prevalent in a wide array of bioactive compounds. Recognizing the limitations current synthetic methodologies─marked by scarcity examples and difficulties flexible functional group modulation─we have developed an efficient modular asymmetric photochemical strategy employing pyridotriazoles boronic acids as substrates. Utilizing novel chiral diamine-derived pyrroles primary amines catalysts, we successfully synthesized diverse range with high yields excellent enantioselectivities. This method not only exhibits broad substrate scope outstanding tolerance but also enables precise synthesis deuterated derivatives using inexpensive D2O deuterium source. Mechanistic studies reveal unusual 1,4-boron shift is critical step generating boronated enamine intermediate, while shedding light on potential enantiocontrol mechanisms facilitated catalyst.

Язык: Английский

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