2H‐Azirines: Recent Progress in Synthesis and Applications

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(11)

Published: Jan. 29, 2024

Abstract 2H ‐arizines are important three‐membered heterocycles in organic chemistry. Recently, many advances the synthesis and functionalization of have been reported. Neber rearrangement, isomerization isoxazole, oxidation enamine, C−H bond activation, decomposition vinyl azide, alkyne, multi‐step developed for efficient assembly ‐azirines. As versatile highly strained unsaturated heterocycles, ‐azirines can be used as distinctive building blocks towards significant functional groups, attracted extensive attention fabrication numerous heterocycles. Recent studies focused on [3+n] ring‐expansion reactions, nucleophilic addition C=N double or continuous followed by cyclization, ring‐opening to acyclic compounds, substitution sp 3 ‐C−H One most critical challenges is seeking a selective opening specific three bonds azirine circle, some what achieved basis metal catalyst, photocatalysis, combination catalyst photocatalysis. In this review, recent involving reactivity accompanied with breakthroughs summarized. The review mainly covers period from 2019 2023.

Language: Английский

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Direct Functionalization of para‐Quinones: A Historical Review and New Perspectives

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(27)

Published: May 21, 2024

Abstract The direct functionalization of quinones has always fascinated research communities due to their biological and redox activities subsequent application. Quinone motifs play a vital role as precursors for many bioactive compounds materials; hence, ingenious methodologies have been elaborated exploring these units. A significant part the synthetic strategies towards functionalized achieved by installing substituents on hydroquinones, phenols, or quinone itself different oxidative coupling reactions via radical pathways with without utilization metal catalysts. simple C−H bond remains challenging inherited electronic nature high dissociation energy. This review article summarizes recent advancement made through quinones. Our primary focus will be approaches mechanistic that appeared in last two decades, along short historical importance family.

Language: Английский

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Photocatalytic Transition‐Metal‐Free Direct 3‐Acetalation of Quinoxaline‐2(1H)‐ones

Chinese Journal of Chemistry, Journal Year: 2022, Volume and Issue: 40(22), P. 2655 - 2662

Published: Aug. 16, 2022

Comprehensive Summary A general transition‐metal‐free visible‐light‐promoted 3‐acetalation reaction of quinoxaline‐2(1 H )‐ones was developed under mild conditions. By employing 1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN) as an inexpensive photocatalyst, and glyoxylic acid acetal a radical source, various acetalated were constructed in moderate to good yields. Moreover, the versatility this protocol is highlighted by successful application late‐stage modification drug molecules functionality transformations. The excellent antitumor activity product demonstrated that streamlined sustainable approach could have emerged powerful strategy for structural medicinal chemistry.

Language: Английский

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Modular Synthesis of Tetrasubstituted Pyrroles through a Four-Component Cyclization Strategy Using Ammonium Salt as the Nitrogen Source

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(3), P. 1533 - 1544

Published: Jan. 19, 2023

A four-component synthesis of tetrasubstituted pyrroles was developed under metal-free conditions. The pyrrole ring formed in one pot through [2 + 1 1] condensation using ammonium salt as the nitrogen source. In this strategy, 1,4-naphthoquinones and maleimides were used versatile C2 fragments to provide substituted benzo[f]isoindole-4,9-diones pyrrolo[3,4-c]pyrrole-1,3-diones, respectively. This work is highlighted by source, readily available starting materials multibond formation (two C–C two C–N bonds) a single operation.

Language: Английский

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Visible‐Light‐Induced C−H Amidation of (Hetero)arenes with Hypervalent Iodine(III) Reagents

Asian Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Abstract A visible‐light‐promoted C−H amidation of (hetero)arenes with hypervalent iodine reagents has been successfully achieved good yields. The high efficiency, broad substrate range and functional group compatibility demonstrated the utility method. Moreover, this protocol was suitable for late‐stage functionalization natural products. Mechanistic studies have shown that N‐centred saccharin radical mediates arenes.

Language: Английский

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Substituted 2H-azirine derivatives - Versatile reagents to access skeletal diversity

Journal of Molecular Structure, Journal Year: 2025, Volume and Issue: unknown, P. 142148 - 142148

Published: March 1, 2025

Language: Английский

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Heterocycle Synthesis Through Photochemical Transformation of 2H-Azirines

Topics in heterocyclic chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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Synthesis of Δ¹-Pyrrolines via Formal (3 + 2)-Cycloaddition of 2H-Azirines with Enones Promoted by Visible Light under Continuous Flow

ACS Omega, Journal Year: 2025, Volume and Issue: unknown

Published: April 22, 2025

Language: Английский

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Desymmetric [3+3] Cyclization of p-Quinamines for the Synthesis of 1,2,4-Oxadiazines and Hydroquinoxalines

Organic Letters, Journal Year: 2024, Volume and Issue: 26(9), P. 1770 - 1774

Published: Feb. 14, 2024

General and efficient strategies for highly diastereoselective synthesis of divergent heterocyclic scaffolds through desymmetric [3+3] cycloaddition p-quinamines with 1,3-dipole surrogates hydroximoyl halides α-halohydroxamates have been developed. This synthetic protocol provided a variety architectures containing 1,2,4-oxadiazine hydroquinoxaline skeletons in good yields wide substrate scope.

Language: Английский

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Visible‐Light‐Induced Metal‐Free Three‐Component Amidoheteroarylation of Alkenes to Synthesize β‐(Hetero)arylethylamines

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(19)

Published: March 21, 2024

Abstract Herein, visible‐light‐induced metal‐free three‐component amidoheteroarylation of alkenes with quinoxalin‐2(1 H )‐ones and N‐sulfonylaminopyridinium salts is developed. This protocol involves a radical relay process in which the N‐centered radicals undergo chemoselective addition to form an alkyl that selectively combines heteroarenes, leading formation C−C C−N bonds one step under mild reaction conditions. The involved high efficiency selectivity, wide substrate scope, excellent functional‐group compatibility demonstrate practicability developed protocol.

Language: Английский

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