Recent developments in 1,6-addition reactions of para-quinone methides (p-QMs)

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(13), С. 1743 - 1778

Опубликована: Янв. 1, 2020

In this review, we provide a comprehensive overview of recent progress in rapidly growing field by summarizing the 1,6-conjugate addition and annulation reactions p-QMs with consideration their mechanisms applications.

Язык: Английский

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para‐Quinone Methides as Acceptors in 1,6‐Nucleophilic Conjugate Addition Reactions for the Synthesis of Structurally Diverse Molecules

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(18), С. 2650 - 2692

Опубликована: Фев. 28, 2020

para ‐Quinone methides ( p ‐QMs) are naturally occurring molecules that have been finding increasing synthetic applications in the last few years. The presence of two electronically different exocyclic conjugate substituents their structure, carbonyl and methylidene, leads to a pronounced reactivity owing polarization molecule. In this sense, those prone undergo attack nucleophiles terminal carbon double bond, behaving as vinylogous electrophiles generating 1,6‐addition products. context, years development catalytic approaches for 1,6‐nucleophilic addition reactions involving ‐QMs has attracted considerable attention. Considering extensive such found decades reactions, review we comprehensively discuss historical field, starting with early on natural product synthesis, going through seminal non‐stereoselective processes progressing cutting‐edge asymmetric‐catalyzed approaches.

Язык: Английский

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Recent Progress in Synthetic Applications of Hypervalent Iodine(III) Reagents

Chemical Reviews, Год журнала: 2024, Номер unknown

Опубликована: Сен. 13, 2024

Hypervalent iodine(III) compounds have found wide application in modern organic chemistry as environmentally friendly reagents and catalysts. iodine are commonly used synthetically important halogenations, oxidations, aminations, heterocyclizations, various oxidative functionalizations of substrates. Iodonium salts arylating reagents, while iodonium ylides imides excellent carbene nitrene precursors. Various derivatives benziodoxoles, such azidobenziodoxoles, trifluoromethylbenziodoxoles, alkynylbenziodoxoles, alkenylbenziodoxoles group transfer the presence transition metal catalysts, under metal-free conditions, or using photocatalysts photoirradiation conditions. Development hypervalent catalytic systems discovery highly enantioselective reactions chiral represent a particularly recent achievement field chemistry. Chemical transformations promoted by many cases unique cannot be performed any other common, non-iodine-based reagent. This review covers literature published mainly last 7-8 years, between 2016 2024.

Язык: Английский

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Bifunctional Phosphonium Salt Directed Enantioselective Formal [4 + 1] Annulation of Hydroxyl-Substituted para-Quinone Methides with α-Halogenated Ketones

Organic Letters, Год журнала: 2019, Номер 21(18), С. 7298 - 7302

Опубликована: Сен. 6, 2019

A highly diastereo- and enantioselective [4 + 1] cycloaddition of para-quinone methides to α-halogenated ketones was realized by bifunctional phosphonium salt catalysis, furnishing functionalized 2,3-dihydrobenzofurans in high yields excellent stereoselectivities (>20:1 dr up >99.9% ee). Mechanistic observations suggested that the reaction underwent a cascade intermolecular substitution/intramolecular 1,6-addition process. DFT calculations revealed presence multiple H-bonding interactions between catalyst enolate intermediate stereodetermining transition states.

Язык: Английский

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Construction of Oxygen‐ and Nitrogen‐based Heterocycles from p‐Quinone Methides

The Chemical Record, Год журнала: 2021, Номер 21(12), С. 4150 - 4173

Опубликована: Авг. 9, 2021

In the last few years, there has been an explosive growth in area of para-quinone methide (p-QM) chemistry. This boom is actually due to unique reactivity pattern p-QMs, and also their remarkable synthetic applications. fact, p-QMs serve as synthons for unsymmetrical diaryl- triarylmethanes, construction diverse range carbocycles heterocycles. a wide structurally complex heterocyclic frameworks could be accessed through transformations modified stable p-QMs. Therefore, main focus this review article cover recent advancements transition-metal, Lewis acid base-catalyzed/mediated p-quinone methides (p-QMs) oxygen- nitrogen-containing

Язык: Английский

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Recent progress in the application of iodonium ylides in organic synthesis

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(24), С. 6999 - 7015

Опубликована: Янв. 1, 2022

This review summarizes the recent advances in synthetic application of iodonium ylides covering 2017 to 2022.

Язык: Английский

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Enantioselective Catalytic [4+1]‐Cyclization of ortho‐Hydroxy‐para‐Quinone Methides with Allenoates

Chemistry - A European Journal, Год журнала: 2019, Номер 25(34), С. 8163 - 8168

Опубликована: Апрель 25, 2019

The first highly asymmetric catalytic synthesis of densely functionalized dihydrobenzofurans is reported, which starts from ortho-hydroxy-containing para-quinone methides. reaction relies on an unprecedented formal [4+1]-annulation these quinone methides with allenoates in the presence a commercially available chiral phosphine catalyst. were obtained as single diastereomers yields up to 90 % and enantiomeric ratios 95:5.

Язык: Английский

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Visible light and base promoted O-H insertion/cyclization of para-quinone methides with aryl diazoacetates: An approach to 2,3-dihydrobenzofuran derivatives

Chinese Chemical Letters, Год журнала: 2021, Номер 32(8), С. 2577 - 2581

Опубликована: Март 7, 2021

Язык: Английский

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Enantioselective Synthesis of Triarylmethanes via Organocatalytic 1,6‐Addition of Arylboronic Acids to para‐Quinone Methides

Advanced Synthesis & Catalysis, Год журнала: 2018, Номер 361(6), С. 1241 - 1246

Опубликована: Дек. 21, 2018

Abstract A method for the preparation of chiral triarylmethanes via organocatalytic 1,6‐addition arylboronic acids to para ‐quinone methides ( p ‐QMs) was established. Here use salicylaldehyde‐derived ‐QMs with an ortho ‐hydroxy substituent as a directing group essential remote stereocontrol. In presence BINOL catalyst, can be obtained in high yields (up 99%) excellent enantioselectivities 99% ee ). This shows broad substrate tolerance and easily scaled up, both electron‐rich electron‐deficient are suitable substrates this addition reaction. magnified image

Язык: Английский

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[4+2]‐Cycloaddition of para‐Quinone Methides with Hexahydro‐1,3,5‐Triazines: Access to 1,3‐Benzoxazine Derivatives

Advanced Synthesis & Catalysis, Год журнала: 2019, Номер 362(3), С. 523 - 527

Опубликована: Ноя. 29, 2019

Abstract A [4+2]‐cycloaddition of para ‐quinone methides with hexahydro‐1,3,5‐triazines is reported. The reaction occurs under very mild conditions (catalyst‐, ligand‐, and base‐free), exhibits a broad substrate scope excellent functional group tolerance, affords series biologically important 1,3‐benzoxazine derivatives in good to yields. Moreover, the successful late‐stage functionalization pharmaceutically relevant compounds further renders approach valuable. magnified image

Язык: Английский

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