Metal-Catalyzed Approaches toward the Oxindole Core

Accounts of Chemical Research, Год журнала: 2020, Номер 53(8), С. 1605 - 1619

Опубликована: Июль 24, 2020

ConspectusThe oxindole scaffold is a privileged structural motif that found in variety of bioactive targets and natural products. Moreover, derivatives the structure are widely present number biologically relevant compounds key intermediates synthesis diverse products pharmaceuticals. Therefore, novel methods to obtain oxindoles remain high priority synthetic organic chemistry.Over past several decades, transition-metal-catalyzed methodologies have been applied toward heterocycles. A detailed mechanistic understanding facilitates disruption traditional catalytic pathways access useful intermediates. The strategies employed generally revolved around generation high-energy organometallic intermediates, which undergo cyclization reactions through domino processes. Domino therefore attractive, as they allow facile functionalized containing all-carbon quaternary centers or tetrasubstituted olefins with chemo- stereoselectivities. Furthermore, these developed can often be easily syntheses other related scaffolds.In this Account, we discuss three unique our group has leveraged for valuable scaffolds. first section Account outlines use an initial oxidative addition C(sp2)–X bond, followed by migratory insertion, yielding neopentyl species amenable subsequent functionalizations. From reactive metal species, reported C–X reductive eliminations, anionic capture cascade reactions, intramolecular C–H functionalization second summarizes group's findings on 1,2-insertions metal–nucleophile across unsaturation, generating intermediate; tethered electrophiles form desired heterocyclic core. We explored wide array transition metal-catalyzed using approach, including rhodium-catalyzed conjugate additions, asymmetric copper-catalyzed borylcupration, palladium(II)-catalyzed chloropalladation protocol. final details dual-metal catalysis perform functionalization–allylation reaction. Throughout provide studies better enabled processes.Overall, exploiting reactivity palladium, nickel, copper, rhodium, ruthenium catalysts develop On basis utility, diversity, applicability developed, believe will prove highly important inspire further development various

Язык: Английский

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Aromatic π-Components for Enantioselective Heck Reactions and Heck/Anion-Capture Domino Sequences

Accounts of Chemical Research, Год журнала: 2022, Номер 55(5), С. 734 - 745

Опубликована: Фев. 4, 2022

ConspectusOlefin functionalization represents one of the most important synthetic transformations in organic synthesis. Over past decades, palladium-catalyzed enantioselective Heck reactions, and Heck/anion-capture domino sequences through olefin carbopalladation followed by termination resulting alkyl-Pd species have been extensively developed. Extension coupling partners from classical olefins to other π-components would enable further advances open new space this field. Aromatics are easily available bulk chemicals. Dearomative transformation endocyclic aromatic π-bonds via reaction pathway provides an efficient straightforward route structurally diverse alicyclic compounds. Nevertheless, major challenges for include aromaticity breaking reactivity selectivity issues.Recently, we engaged developing catalytic dearomative reactions related reactions. A range heteroarenes naphthalenes employed as novel π-coupling these Through migratory insertion C–C interception transient species, reductive difunctionalization heteroarenyne cycloisomerization established. Relying on β-H elimination intermediate, realized with a partners, including heterocyclic indoles, pyrroles, furans, benzofurans, more challenging carbocyclic naphthalenes. In order avoid utilization organohalide electrophiles, was developed merging intermolecular alkyne hydropalladation intramolecular reaction. Cycloisomerization alkyne-tethered indoles delivered chiral indolines excellent enantioselectivities 100% atom economy. On hand, were established nucleophilic trapping intermediate. When HCO2Na capturing reagent, realized. By employing nucleophiles, alkynes, N-sulfonylhydrazones, organoboron reagents, series Two vicinal stereocenters enantio- diastereoselectivities constructed corresponding Heck/Sonogashira, Heck/vinylation, Heck/borylation Moreover, 1,4-diarylation Heck/Suzuki which competitive C–H arylation direct Suzuki almost fully inhibited presence spiro-phosphoramidite ligand.In Account, provide panoramic view our results since 2015 extending systems. Investigations outlined Account access variety heteropolycyclic molecules starting simple planar

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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The emergence of Pd-mediated reversible oxidative addition in cross coupling, carbohalogenation and carbonylation reactions

Nature Catalysis, Год журнала: 2019, Номер 2(10), С. 843 - 851

Опубликована: Окт. 7, 2019

Язык: Английский

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Palladium‐Catalyzed Enantioselective Heteroarenyne Cycloisomerization Reaction

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(13), С. 7412 - 7417

Опубликована: Янв. 13, 2021

Abstract The extensively developed ene‐type enantioselective cycloisomerization of classical 1,n‐enynes provides an efficient approach to chiral cyclic 1,4‐dienes. In contrast, the catalytic asymmetric heteroarenyne (heteroarene–alkyne) involving dearomative transformation endocyclic aromatic C=C bonds remains unknown. Herein, we communicate a PdH‐catalyzed reaction alkyne‐tethered indole substrates (formal 1,5‐ and 1,6‐enynes). Based on this strategy, variety structurally diverse spiro fused indoline derivatives bearing quaternary stereocenters exocyclic are afforded in moderate excellent yields enantioselectivities (up 98 % ee). 1,5‐enyne N ‐vinylpropiolamides is also afford 2‐pyrrolones good ee values.

Язык: Английский

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Nickel‐Catalyzed Intermolecular Asymmetric Addition of Aryl Iodides across Aldehydes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(20)

Опубликована: Фев. 11, 2022

Enantioenriched alcohols comprise much of the framework organic molecules. Here, we first report that chiral nickel complexes can catalyze intermolecular enantioselective addition aryl iodides across aldehydes to provide diverse optically active secondary using zinc metal as reducing agent. This method shows a broad substrate scope under mild reaction conditions and precludes traditional strategy through pre-generation organometallic reagents. Mechanistic studies indicate an in situ formed arylnickel, instead arylzinc, adds efficiently aldehydes, forming new C-C bond alkoxide may be turned over by powder.

Язык: Английский

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Nickel-Catalyzed Enantioselective Carbamoyl Iodination: A Surrogate for Carbamoyl Iodides

ACS Catalysis, Год журнала: 2020, Номер 10(8), С. 4780 - 4785

Опубликована: Март 26, 2020

This work reports the enantioselective formal transfer of a carbamoyl iodide across 1,1-disubstituted styrene using Ni-catalysis. Employing an air-stable Ni(II) precatalyst and commercially available chiral ligand ((S)-tBuPHOX), enantioenriched 3,3-disubstituted iodooxindoles were obtained in up to 90% yield 97:3 e.r. methodology was applied total synthesis (−)-esermethole (−)-phenserine.

Язык: Английский

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Migratory Insertion Strategies for Dearomatization

Synthesis, Год журнала: 2019, Номер 51(22), С. 4137 - 4146

Опубликована: Авг. 26, 2019

Development of strategies for molecule functionalization by dearomatization has surged in the last two decades. The benefits overcoming resonance stabilization energy outweigh cost; diverse compounds could be accessed a short number steps. One approach that been interest recent years is indoles and other (hetero)aromatic migratory insertion. chiral σ-bond palladium intermediate reduced or trapped second functionalization. In this review we will summarize recently discovered reactions from our group others field metal-catalyzed dearomatizations 1 Introduction 2 Monofunctionalizations: Heck Reductive Reactions 2.1 N-Tethered Heterocycles 2.2 Non-N-tethered 2.3 Non-heterocycles 3 Dearomative Difunctionalizations: Interrupted Reaction 3.1 3.2 4 Conclusion

Язык: Английский

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Isoindolinone Synthesis via One‐Pot Type Transition Metal Catalyzed C−C Bond Forming Reactions

Chemistry - A European Journal, Год журнала: 2020, Номер 27(17), С. 5344 - 5378

Опубликована: Окт. 30, 2020

Isoindolinone structure is an important privileged scaffold found in a large variety of naturally occurring as well synthetic, biologically and pharmaceutically active compounds. Owing to its crucial role number applications, the synthetic methodologies for accessing this heterocyclic skeleton have received significant attention during past decade. In general, strategies can be divided into two categories: First, direct utilization phthalimides or phthalimidines starting materials synthesis isoindolinones; second, construction lactam and/or aromatic rings by different catalytic methods, including C-H activation, cross-coupling, carbonylation, condensation, addition formal cycloaddition reactions. Especially last mentioned, transition metal catalysts provides access broad range substituted isoindolinones. Herein, recent advances (2010-2020) catalyzed via formation new C-C bonds isoindolinones are reviewed.

Язык: Английский

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Dearomative 1,4-difunctionalization of naphthalenes via palladium-catalyzed tandem Heck/Suzuki coupling reaction

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

Опубликована: Сен. 1, 2020

Dearomative functionalization reactions represent an important strategy for the synthesis of valuable three-dimensional molecules from simple planar aromatics. Naphthalene is a challenging arene towards transition-metal-catalyzed dearomative difunctionalization reactions. Reported herein application naphthalene as masked conjugated diene in palladium-catalyzed 1,4-diarylation or 1,4-vinylarylation reaction via tandem Heck/Suzuki sequence. Three types 1,4-dihydronaphthalene-based spirocyclic compounds are achieved excellent regio- and diastereoselectivities. Key to this transformation inhibition few competitive side reactions, including intramolecular naphthalenyl C-H arylation, intermolecular Suzuki cross-coupling, 1,2-difunctionalization, reductive-Heck reaction. Density functional theory (DFT) calculations imply that facile exergonic insertion double bond disrupts sequence direct coupling, leading coupling The observed regioselectivity 1,4-difunctionalization due steric repulsions between introduced aryl group spiro-scaffold 1,2-difunctionalization.

Язык: Английский

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