Lewis Base Promoted [4+2] Annulation of o-Acylamino-aryl MBH Carbonates with Isatin

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

The first example of Lewis base promoted [4 + 2] annulation between

Язык: Английский

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Lewis Base Promoted [4+2] Annulation of o‐Acylamino‐Aryl Morita‐Baylis‐Hillman Carbonates With Isatylidene Malononitriles: Facile Access to Spiro[Indolin‐3,2′‐Quinoline] Frameworks

Journal of Heterocyclic Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Окт. 10, 2024

ABSTRACT A novel [4+2] annulation reaction between o ‐acylamino‐aryl MBH carbonates and isatylidene malononitriles has been successfully developed. This methodology exhibits excellent substrate tolerance, affording a series of spiro[indolin‐3,2′‐quinoline] framework compounds with yields up to 98%. The scalability the is also noteworthy, as evidenced by 95% yield final product upon 50‐fold scale‐up.

Язык: Английский

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Selective Preparation of Pyrrolo[2,3‐c]tetrahydroquinolines and Indolo[3,2‐c]tetrahydroquinolines through N‐Arylation/Cycloaddition/Rearrangement Annulation Reactions of Alkynyl‐Tethered Oximes with Diaryliodonium Salts

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Окт. 25, 2024

Abstract We describe a selective preparation of variety functionalized pyrrolo[2,3‐ c ]tetrahydroquinolines and indolo[3,2‐ in 40–82% 40–80% yields from alkynyl‐tethered oximes with diaryliodonium triflates, respectively. The one‐pot reaction underwent N ‐arylation, intramolecular [3+2] cycloaddition, [1.3] or [3,3]‐rearrangement N−O bond total three steps. Experimental studies revealed that EtOAc solvent copper(II)‐catalyst played crucial roles on the formation these two tetrahydroquinoline scaffolds. Moreover, scaffolds could be converted into various building blocks by further transformations.

Язык: Английский

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Base-Promoted Formal (3 + 2) Cycloaddition of α-Halohydroxamates with Electron-Deficient Alkenyl-iminoindolines To Synthesize Spiro-indolinepyrrolidinones

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(20), С. 14619 - 14633

Опубликована: Окт. 4, 2023

Construction of pyrrolidinyl-spiroindoles with easily available starting materials has attracted considerable attention from the synthesis community and is in great demand. Here, we describe a base-promoted formal (3 + 2) cycloaddition α-halohydroxamates alkenyl-iminoindolines. The present methodology features mild reaction conditions broad substrate scope up to 99% yield excellent diastereoselectivity. versatility this approach demonstrated through valuable synthetic transformations. Preliminary mechanistic studies shed light on mechanism process.

Язык: Английский

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Stereoselective skeletal modification of tryptanthrins to install chiral piperidine-2-ones enabled by Brønsted acid catalysis

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(8), С. 2171 - 2177

Опубликована: Янв. 1, 2024

An asymmetric formal [4 + 2] cyclisation between azlactones and aza-dienes derived from simple tryptanthrins has been developed. With this established protocol, yielding a series of novel piperidine-2-one-fused with up to >99 : 1 er under mild conditions.

Язык: Английский

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Bifunctional Lewis Base-Catalyzed (3 + 2) Cycloadditions of Pyrazolone-Derived MBH Carbonates with Arynes

Organic Letters, Год журнала: 2024, Номер 26(42), С. 9108 - 9113

Опубликована: Окт. 16, 2024

The (3 + 2) cycloaddition of arynes with allylic ylides remains a formidable challenge because both intermediates are highly reactive and prone to spontaneous quenching. Here, we report pyrazolone MBH carbonates arynes, enabling the efficient synthesis diverse indene-fused spiropyrazolones. key is employing new bifunctional Lewis base catalyst facilitate

Язык: Английский

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Enantioselective Cascade Catalysis for the Construction of Tetrahydroquinolines

Organic Letters, Год журнала: 2024, Номер 26(44), С. 9448 - 9454

Опубликована: Окт. 30, 2024

Secondary amines are widely used as robust catalysts for the enantioselective functionalization of aldehydes, yet they rarely employed Lewis bases or hydrogen-bonding alkene activation. In this study, we present a decarboxylative [4 + 2] cycloaddition vinyl benzoxazinanones with nitroolefins to construct tetrahydroquinolines through cascade catalysis. A single chiral morpholine catalyst sequentially functions both base and catalyst. These activation modes effectively drive process control stereochemistry.

Язык: Английский

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The [4+2] Annulation of o-Acylamino-aryl MBH Carbonates with Coumarins: Facile Access to Tetrahydrochromeno[4,3-b]quinolin-6-ones

New Journal of Chemistry, Год журнала: 2024, Номер 49(3), С. 683 - 686

Опубликована: Дек. 16, 2024

This study presents a [4+2] annulation reaction with o -acylamino-aryl MBH carbonates and coumarins, yielding tetrahydrochromeno[4,3- b ]quinolin-6-ones up to 95% efficiency excellent substrate tolerance.

Язык: Английский

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