Stereodivergent Synthesis of Tetrahydrofuroindoles through Pd‐Catalyzed Asymmetric Dearomative Formal [3+2] Cycloaddition

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(8), С. 2134 - 2138

Опубликована: Янв. 13, 2018

A stereodivergent synthesis of tetrahydrofuroindoles through palladium-catalyzed asymmetric dearomative formal [3+2] cycloaddition nitroindoles with epoxybutenes was developed. The polarity the solvent found to play a key role in diastereoselectivity. In toluene, good excellent yields (70-99 %), diastereoselectivity (87/13->95/5 d.r.), and enantioselectivity (85/15-94/6 e.r.) were obtained, regardless properties substituents on nitroindoles. acetonitrile, different diastereoisomer produced (75-98 %) stereoselectivity (78/22-93/7 d.r., 93/7-99/1 e.r.). Mechanistic studies conducted illustrate origin diastereodivergency. kinetic experiments indicate that rate-determining step this reaction is solvents. ESI-MS also support existence palladium complex intermediates catalytic cycle reaction.

Язык: Английский

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Phosphine‐Catalyzed Enantioselective Dearomative [3+2]‐Cycloaddition of 3‐Nitroindoles and 2‐Nitrobenzofurans

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(16), С. 5422 - 5426

Опубликована: Фев. 12, 2019

Abstract Over the past years, metal‐catalyzed dearomative cycloaddition of 3‐nitroindoles and 2‐nitrobenzofurans have emerged as a powerful protocol to construct chiral fused heterocyclic rings. However, organocatalytic reaction these two classes heteroarenes has become long‐standing challenging task. Herein, we report first example phosphine‐catalyzed asymmetric [3+2]‐cycloadditio 2‐nitrobenzofurans, which provide new, facile, efficient for synthesis 2,3‐fused cyclopentannulated indolines dihydrobenzofurans by reacting with allenoates MBH carbonates, respectively through [3+2]‐cycloaddition.

Язык: Английский

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Pd‐Catalyzed Dearomatization of Anthranils with Vinylcyclopropanes by [4+3] Cyclization Reaction

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(17), С. 5739 - 5743

Опубликована: Фев. 27, 2019

Abstract Dearomatization of anthranils with vinylcyclopropanes (VCPs) by Pd‐catalyzed [4+3] cyclization reaction has been realized. In the presence a catalytic amount borane as an activator, bridged cyclic products were obtained in good to excellent yields stereoselectivities. By introducing chiral PHOX ligand ( L5 ), asymmetric dearomatization reactions proceeded enantioselectivity. Borane plays key role for reactivity, likely owing formation borane–anthranil complex which confirmed NMR experiments.

Язык: Английский

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Recent Advances in the Catalytic Dearomatization of Naphthols

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(27), С. 4087 - 4097

Опубликована: Фев. 19, 2020

The catalytic dearomatization of naphthols offers a unique platform to rapidly access structurally complex and densely functionalized molecular architectures. Thermodynamically more favorable, with respect the analogous phenol‐variant, transformation phenolic ring into corresponding naphthalenone (cited here as naphthyl dearomatization) has faced considerable amount attention over past decade constant improvements towards stereocontrol. A collection most representative recent variants involving carbon–carbon well carbon–heteroatom bond forming events are presented in this Minireview article.

Язык: Английский

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Enantioselective Copper-Catalyzed Dearomative Spiroannulation of β-Naphthols or Indoles with Yne-Allylic Esters

ACS Catalysis, Год журнала: 2024, Номер 14(12), С. 9254 - 9264

Опубликована: Июнь 3, 2024

Catalytic asymmetric dearomatization reactions of α-unsubstituted β-naphthols are very challenging due to the high energy barrier resulting from loss aromaticity. Herein, we describe an example enantioselective catalytic dearomative spiroannulation with yne-allylic esters. The success this reaction relied on copper-catalyzed remote strategy using esters as bis-electrophilic reagents. This transformation features mild conditions, broad functional group tolerance, and extensive substrate scope, thereby facilitating efficient construction array enantioenriched naphthalene-2-one spiroindolenine derivatives. Experimental studies density theory calculations establish pathway origin stereoselectivity.

Язык: Английский

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Catalytic asymmetric multiple dearomatizations of phenols enabled by a cascade 1,8-addition and Diels–Alder reaction

Chemical Science, Год журнала: 2019, Номер 11(3), С. 671 - 676

Опубликована: Дек. 6, 2019

The first chiral phosphoric acid catalyzed asymmetric multiple dearomatizations of phenols for the synthesis bridged polycyclic compounds are reported.

Язык: Английский

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Chiral phosphoric acid catalyzed aminative dearomatization of α-naphthols/Michael addition sequence

Nature Communications, Год журнала: 2019, Номер 10(1)

Опубликована: Июль 17, 2019

Asymmetric dearomatization reactions have recently emerged as a powerful tool for the rapid build-up of molecular complexity. Chiral three-dimensional polycyclic molecules bearing contiguous stereogenic centers can be synthesized from readily available planar aromatic feedstocks. Here we report that an intermolecular asymmetric reaction α-naphthols tethered nucleophile at C4 position naphthol ring is achieved by chiral phosphoric acid. The proceeds via highly chemo- and regioselective aminative dearomatization/Michael addition sequence, affording wide array functionalized cyclic ketones in good yields (up to 93%) with excellent enantioselectivity >99% ee). catalyst loading reduced 0.1 mol%. Preliminary mechanistic investigations identify established step, while Michael rate-limiting step. A working model accounting origin stereochemistry proposed based on DFT calculations.

Язык: Английский

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Asymmetric Dearomative Fluorination of 2‐Naphthols with a Dicarboxylate Phase‐Transfer Catalyst

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(33), С. 14101 - 14105

Опубликована: Май 11, 2020

Abstract A linked dicarboxylate phase‐transfer catalyst enables smooth asymmetric dearomative fluorination of 2‐naphthols with Selectfluor under mild conditions to give the corresponding 1‐fluoronaphthalenone derivatives in a highly enantioselective manner. This reaction, which is compatible range functional groups, first example catalytic 2‐naphthols, and expected be useful synthesis bioactive molecules.

Язык: Английский

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Organocatalytic Asymmetric Dearomatization Reaction for the Synthesis of Axial Chiral Allene-Derived Naphthalenones Bearing Quaternary Stereocenters

Organic Letters, Год журнала: 2021, Номер 23(17), С. 6606 - 6611

Опубликована: Авг. 13, 2021

The highly regio-, diastereo-, and enantioselective dearomatization reaction of 1-substituted 2-naphthols β,γ-alkynyl-α-imino esters with complete atom economy is disclosed via chiral phosphoric acid catalysis. This protocol provides facile efficient access to asymmetric construction a broad range axially allene-derived naphthalenones bearing quaternary stereocenters in good yields high diastereoselectivities enantioselectivities.

Язык: Английский

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meta-Selective C–H arylation of phenols via regiodiversion of electrophilic aromatic substitution

Nature Chemistry, Год журнала: 2022, Номер 15(3), С. 386 - 394

Опубликована: Дек. 12, 2022

Язык: Английский

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