Catalytic Asymmetric Construction of Axially Chiral Indole‐Based Frameworks: An Emerging Area

Chemistry - A European Journal, Год журнала: 2020, Номер 26(68), С. 15779 - 15792

Опубликована: Май 4, 2020

Axially chiral indole-based frameworks have been recognized as a class of important five-membered heterobiaryls and developing catalytic asymmetric approaches for constructing these in an enantioselective manner is highly desirable. In recent years, synthetic chemists paid much attention to this research field, rapid developments occurred. At point, range axially scaffolds constructed via various reactions based on different strategies. Thus, the construction has become emerging area. This minireview summarizes advances field gives some insights into future developments, which will help thrive.

Язык: Английский

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Progresses in organocatalytic asymmetric dearomatization reactions of indole derivatives

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(23), С. 3967 - 3998

Опубликована: Янв. 1, 2020

This review summarizes the progresses in organocatalytic asymmetric dearomatization reactions of indole derivatives and their applications total synthesis natural products, gives some insights into challenging issues this research field.

Язык: Английский

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Cascade asymmetric dearomative cyclization reactions via transition-metal-catalysis

Nature Synthesis, Год журнала: 2022, Номер 1(3), С. 203 - 216

Опубликована: Март 14, 2022

Язык: Английский

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Reductive dearomative arylcarboxylation of indoles with CO2 via visible-light photoredox catalysis

Nature Communications, Год журнала: 2020, Номер 11(1)

Опубликована: Июнь 29, 2020

Abstract Catalytic reductive coupling of two electrophiles and one unsaturated bond represents an economic efficient way to construct complex skeletons, which is dominated by transition-metal catalysis via electron transfer. Herein, we report a strategy visible-light photoredox-catalyzed successive single transfer, realizing dearomative arylcarboxylation indoles with CO 2 . This avoids common side reactions in catalysis, including ipso-carboxylation aryl halides β-hydride elimination. photoredox shows high chemoselectivity, low loading photocatalyst, mild reaction conditions (room temperature, 1 atm) good functional group tolerance, providing great potential for the synthesis valuable but difficultly accessible indoline-3-carboxylic acids. Mechanistic studies indicate that benzylic radicals anions might be generated as key intermediates, thus direction couplings other electrophiles, D O aldehyde.

Язык: Английский

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Atroposelective Construction of Axially Chiral Alkene‐Indole Scaffolds via Catalytic Enantioselective Addition Reaction of 3‐Alkynyl‐2‐indolylmethanols^†

Chinese Journal of Chemistry, Год журнала: 2021, Номер 39(8), С. 2163 - 2171

Опубликована: Апрель 29, 2021

Main observation and conclusion Atroposelective construction of axially chiral alkene‐heteroaryl scaffolds is highly desired but challenging. In this work, we established an atroposelective alkene‐indole via the strategy catalytic enantioselective addition reaction 3‐alkynyl‐2‐indolylmethanols with bulky nucleophiles. strategy, α‐amido sulfones were used as competent nucleophiles phosphoric acid (CPA) acted suitable catalyst for reaction. By a new class acyclic alkene‐indoles was synthesized in overall high yields (up to 86%), excellent ( E / Z )‐selectivity (all > 95 : 5) good enantioselectivities 92 8 er). This represents first frameworks, which will add member family atropoisomeric heterocycles, especially indole compounds.

Язык: Английский

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Visible-Light-Induced Dearomatization of Indoles/Pyrroles with Vinylcyclopropanes: Expedient Synthesis of Structurally Diverse Polycyclic Indolines/Pyrrolines

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(33), С. 13441 - 13449

Опубликована: Авг. 16, 2021

Visible-light-induced cycloaddition reactions initiated via energy-transfer processes have recently evolved as powerful methods for the construction of strained cyclic molecules that are not easily accessed using known ground-state synthetic methods. Particularly, by excitation aromatic rings provide an alternative solution to direct transformations feedstocks under scheme dearomatization. Vinylcyclopropanes (VCPs) well-known reagents in radical clock experiments, working a probe detect transient intermediates. However, applications this regard still remain limited due uncontrollable selectivities. Herein, we report visible-light-induced dearomatization indole- or pyrrole-tethered VCPs, which several competitive reaction pathways, including [5 + 2], [2 interrupted and 4] cycloadditions, can be well regulated engineering substrate structures tuning conditions. The mechanism has been explored combined experimental computational investigations. These convenient method synthesize structurally diverse polycyclic with high efficiency good selectivity.

Язык: Английский

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Asymmetric Dearomatization of Indoles with Azodicarboxylates via Cascade Electrophilic Amination/Aza-Prins Cyclization/Phenonium-like Rearrangement

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(21), С. 11745 - 11753

Опубликована: Май 19, 2023

Herein, we report a highly efficient synthesis of enantioenriched aza-[3.3.1]-bicyclic enamines and ketones, class structural cores in many natural products, via asymmetric dearomatization indoles with azodicarboxylates. The reaction is initiated by electrophilic amination followed aza-Prins cyclization/phenonium-like rearrangement. A newly developed fluorine-containing chiral phosphoric acid displays excellent activity promoting this cascade reaction. absence or presence water as the additive directs pathway toward either enamine ketone products high yields (up to 93%) enantiopurity 98% ee). Comprehensive density functional theory (DFT) calculations reveal energy profile origins enantioselectivity water-induced chemoselectivity.

Язык: Английский

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Silver-Enabled Dearomative Trifluoromethoxylation of Indoles

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(4), С. 2325 - 2332

Опубликована: Янв. 17, 2024

The only known method for the dearomative trifluoromethoxylation of indoles is preliminary, with one substrate successfully undergoing reaction. In this study, we not developed a broadly applicable indole but also achieved divergent by fine-tuning reaction conditions. Under optimized conditions, silver salt and an easily handled OCF3 reagent, various smoothly underwent dearomatization to afford diverse array ditrifluoromethoxylated indolines in 50–84% isolated yields up 37:1 diastereoselectivity, fluorinated trifluoromethoxylated were obtained exclusive trans selectivity. addition, conditions compatible other heteroaromatic rings as well styrene moieties.

Язык: Английский

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Gd(III)-Catalyzed Regio-, Diastereo-, and Enantioselective [4 + 2] Photocycloaddition of Naphthalene Derivatives

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(25), С. 16982 - 16989

Опубликована: Июнь 13, 2024

Catalytic asymmetric dearomatization (CADA) reactions have evolved into an efficient strategy for accessing chiral polycyclic and spirocyclic scaffolds from readily available planar aromatics. Despite the significant developments, CADA reaction of naphthalenes remains underdeveloped. Herein, we report a Gd(III)-catalyzed naphthalene with PyBox ligand via visible-light-enabled [4 + 2] cycloaddition. This features application Gd/PyBox complex, which regulates reactivity selectivity simultaneously, in excited-state catalysis. A wide range functional groups is compatible this protocol, giving highly enantioenriched bridged polycycles excellent yields (up to 96%) >20:1 chemoselectivity, dr, >99% ee). The synthetic utility demonstrated by 2 mmol scale reaction, removal directing group, diversifications products. Preliminary mechanistic experiments are performed elucidate mechanism.

Язык: Английский

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Photo-induced intramolecular dearomative [5 + 4] cycloaddition of arenes for the construction of highly strained medium-sized-rings

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

Опубликована: Март 19, 2024

Abstract Medium-sized-ring compounds have been recognized as challenging synthetic targets in organic chemistry. Especially, the difficulty of synthesis will be augmented if an E -olefin moiety is embedded. Recently, photo-induced dearomative cycloaddition reactions that proceed via energy transfer mechanism witnessed significant developments and provided powerful methods for transformations are not easily realized under thermal conditions. Herein, we report intramolecular [5 + 4] naphthalene-derived vinylcyclopropanes visible-light irradiation a proper triplet photosensitizer. The reaction affords dearomatized polycyclic molecules possessing nine-membered-ring with good yields (up to 86%) stereoselectivity 8.8/1 / Z ). Detailed computational studies reveal origin behind favorable formation thermodynamically less stable isomers. Diverse derivations products also demonstrated.

Язык: Английский

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