Recent advances in cyclization reactions of unsaturated oxime esters (ethers): synthesis of versatile functionalized nitrogen-containing scaffolds

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(14), С. 1948 - 1969

Опубликована: Янв. 1, 2020

We summarized recent advances in cyclization reactions of unsaturated oxime esters (ethers), which provide diversiform functionalized nitrogen-containing scaffolds.

Язык: Английский

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NH₄I-Triggered [4 + 2] Annulation of α,β-Unsaturated Ketoxime Acetates with N-Acetyl Enamides for the Synthesis of Pyridines

The Journal of Organic Chemistry, Год журнала: 2020, Номер 85(12), С. 8157 - 8165

Опубликована: Июнь 1, 2020

The NH4I-triggered formal [4 + 2] annulation of α,β-unsaturated ketoxime acetates with N-acetyl enamides has been developed. current protocol employs electron-rich as C2 synthons and enables the efficient straightforward construction polysubstituted pyridines in moderate to good yields based on metal-free systems. reaction tolerates a wide range functional groups represents an alternate route toward synthesis pyridine derivatives.

Язык: Английский

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Trifunctionalization of alkenes and alkynes

Organic & Biomolecular Chemistry, Год журнала: 2020, Номер 18(40), С. 7948 - 7976

Опубликована: Янв. 1, 2020

In this review, the development of trifunctionalization methods for alkenes and alkynes, including arynes allenes, over last decade is disclosed.

Язык: Английский

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Iron-catalyzed [4 + 2] annulation of α,β-unsaturated ketoxime acetates with enaminones toward functionalized pyridines

Green Synthesis and Catalysis, Год журнала: 2021, Номер 2(2), С. 237 - 240

Опубликована: Март 28, 2021

The iron-catalyzed [4 ​+ ​2] annulation of α,β-unsaturated ketoxime acetates with enaminones has been developed, providing efficient access to highly substituted pyridines in moderate good yields. Notable features the present strategy include low-cost catalytic system, simple and mild reaction condition wide substrate scope. Mechanistic studies reveal that FeCl2 may directly serve as a Lewis acid activate for nucleophilic addition.

Язык: Английский

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Synthesis of Stable N–H Imines with a Benzo[7,8]indolizine Core and Benzo[7,8]indolizino[1,2-c]quinolines via Copper-Catalyzed Annulation of α,β-Unsaturated O-Acyl Ketoximes with Isoquinolinium N-Ylides

Organic Letters, Год журнала: 2022, Номер 24(21), С. 3828 - 3833

Опубликована: Май 23, 2022

A copper-catalyzed annulation of α,β-unsaturated O-acyl ketoximes with isoquinolinium N-ylides has been developed for the concise synthesis stable N-H imines a benzo[7,8]indolizine core. When β-(2-bromoaryl)-α,β-unsaturated are used as starting materials, cascade cyclization occurs to afford benzo[7,8]indolizino[1,2-c]quinolines.

Язык: Английский

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Construction of Pyridine Ring Systems by Mn(OAc)₂‐Promoted Formal Dehydrative Dehydroaromatizing [4+2] Cycloaddition of Enamides with Maleimides

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(10), С. 1683 - 1688

Опубликована: Март 31, 2022

Abstract Herein, we report a Mn(OAc) 2 ‐promoted formal dehydrative dehydroaromatizing [4+2] cycloaddition of enamides with maleimides for the construction pyridine rings to access diverse synthetically valuable pyrrolo[3,4‐c]‐pyridine derivatives. This protocol allows two C−C bond formation assembly derivatives from synthesizable in steps and inexpensive maleimides, which exhibits broad substrate scope good functional group compatibility. magnified image

Язык: Английский

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Copper-catalyzed three-component annulation toward pyrroles via the cleavage of two C–C bonds in 1,3-dicarbonyls

Chemical Communications, Год журнала: 2023, Номер 59(71), С. 10636 - 10639

Опубликована: Янв. 1, 2023

The first copper-catalyzed three-component annulation of α,β-unsaturated ketoximes, 1,3-dicarbonyls and paraformaldehyde has been documented. This novel strategy achieved the two C-C bond cleavage 1,3-dicarbonyl compounds directly as a single-carbon synthon provided new highly efficient method for synthesis 2,3-disubstituted pyrroles in moderate to good yields with broad functional group compatibility.

Язык: Английский

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Iodine‐Promoted Synthesis of Dipyrazolo/Diuracil‐Fused Pyridines and o‐Amino Diheteroaryl ketones via Oxidative Domino Annulation of 2/4‐Methylazaarenes

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(19), С. 4632 - 4638

Опубликована: Авг. 24, 2021

Abstract The iodine‐promoted oxidative domino annulation and carbonylation process has been developed for the synthesis of biologically important azaarene‐substituted bis‐pyrazolo[3,4‐ b :4′,3′‐ e ]pyridines (BPPs), diuracilpyridines o ‐amino diheteroaryl ketones. procedure proceeded with easily available methyl azaarenes, 5‐aminouracils substituted 5‐aminopyrazoles. This protocol is a simple metal‐free approach which exhibits high functional group compatibility broad substrates scope. Moreover, this transformation can be applied preparation dipyrazolo/diuracil‐fused pyridines on gram scale. magnified image

Язык: Английский

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1,2,4‐Triazines and Calcium Carbide in the Catalyst‐Free Synthesis of 2,3,6‐Trisubstituted Pyridines and Their D‐, ¹³C‐, and Doubly D₂‐¹³C₂‐Labeled Analogues

Chemistry - An Asian Journal, Год журнала: 2023, Номер 18(23)

Опубликована: Окт. 16, 2023

A novel synthetic approach to 2,3,6-trisubstituted pyridines, their 4,5-dideuterated derivatives, 4,5-13 C2 - and doubly-labeled D2 -13 -pyridines has been developed using catalyst-free [4+2] cycloaddition of 1,2,4-triazines in situ generated acetylene or labeled acetylene. Calcium carbide water deuterium oxide were used for the generation dideuteroacetylene. carbide-13 mixture with was applied as 13 -acetylene source.

Язык: Английский

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Mild and efficient copper-catalyzed oxidative cyclization of oximes with 2-aminobenzyl alcohols at room temperature: synthesis of polysubstituted quinolines

Organic & Biomolecular Chemistry, Год журнала: 2020, Номер 19(3), С. 659 - 666

Опубликована: Дек. 22, 2020

A simple and efficient protocol for the synthesis of polysubstituted quinolines at room temperature has been developed by ligand-free Cu-catalyzed oxidative cyclization oxime acetates with 2-aminobenzyl alcohols.

Язык: Английский

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