2H‐Azirines: Recent Progress in Synthesis and Applications

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(11)

Опубликована: Янв. 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.

Язык: Английский

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TMSOTf-Catalyzed [4 + 2] Annulation of Ynamides and β-(2-Aminophenyl)-α,β-ynones for the Synthesis 2-Aminoquinolines

Organic Letters, Год журнала: 2024, Номер 26(17), С. 3503 - 3508

Опубликована: Апрель 25, 2024

A metal-free TMSOTf-catalyzed [4 + 2] annulation of ynamides with β-(2-aminophenyl)-α,β-ynones enables the regiospecific and facile assembly 2-aminoquinoline frameworks. The catalyst TMSOTf presented a remarkable advancement compared to previously reported transition-metal catalysts. wide range 3-aryl/alkyl-substituted 2-aminoquinolines were generated in moderate excellent yields due mild conditions.

Язык: Английский

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Pd-Catalyzed Regioselective Tandem Heck/C–H Activation/Bisamination Reactions with Ynamides and Diaziridinone. Rapid Access to 3-Aminoindoles

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Май 19, 2025

This work describes a highly efficient Pd-catalyzed annulation process of aryl iodides, ynamides, and di-tert-butyldiaziridinone. A wide variety 3-aminoindoles bearing various functional groups have been readily obtained in up to 99% yield. 3-Aminoindole functionalities can also be easily introduced into medicinally important molecules. The reaction likely proceeds through sequential regioselective Heck C-H activation form pallada(II)cycle species, which is bisaminated with diaziridinone via pallada(IV)cycle intermediate. resulting serve as versatile precursors for the construction structurally diverse aza-polycyclic compounds.

Язык: Английский

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Triethylamine-Promoted Oxidative Cyclodimerization of 2H-Azirine-2-carboxylates to Pyrimidine-4,6-dicarboxylates: Experimental and DFT Study

Molecules, Год журнала: 2023, Номер 28(11), С. 4315 - 4315

Опубликована: Май 24, 2023

An unprecedented oxidative cyclodimerization reaction of 2H-azirine-2-carboxylates to pyrimidine-4,6-dicarboxylates under heating with triethylamine in air is described. In this reaction, one azirine molecule undergoes formal cleavage across the C-C bond and another C=N bond. According experimental study DFT calculations, key steps mechanism include nucleophilic addition N,N-diethylhydroxylamine an form (aminooxy)aziridine, generation azomethine ylide, its 1,3-dipolar cycloaddition second molecule. The crucial condition for synthesis pyrimidines mixture a very low concentration, which ensured by slow oxidation oxygen. Addition radical initiator accelerated resulted higher yields pyrimidines. Under these conditions, scope pyrimidine formation was elucidated, series synthesized.

Язык: Английский

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Catalysts-Controlled Roles Exchange between 2,3-Diaryl-2H-azirines and Acetone: Chemodivergent Synthesis of Pyrroles and 3-Oxazolines

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(9), С. 6064 - 6073

Опубликована: Апрель 11, 2024

We report two practical and step-economical methodologies for the chemodivergent synthesis of tri-substituted pyrroles 3-oxazolines from domino reactions 2H-azirines acetone. For instance, acetone served as a nucleophile to react with under basic conditions furnish pyrroles. Upon changing catalyst TfOH, an electrophile synthesize 3-oxazolines. Moreover, products could be synthesized on gram scale, possible catalytic cycles were proposed.

Язык: Английский

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Metal-free [2 + 2] and [4 + 2] cycloadditions ofN-aryl-substituted ynamides to construct functionalized aminocyclobutenes and 4-aminoquinolines

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(16), С. 4043 - 4054

Опубликована: Янв. 1, 2023

Metal-free [2 + 2] and [4 self-cycloadditions of N -aryl-substituted ynamides provide various valuable functionalized aminocyclobutenes 4-aminoquinoline derivatives.

Язык: Английский

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Five-membered ring systems: pyrroles and benzo analogs

Progress in heterocyclic chemistry, Год журнала: 2023, Номер unknown, С. 199 - 250

Опубликована: Янв. 1, 2023

Язык: Английский

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Brønsted acid catalyzed Ficini [2 + 2] cycloaddition of ynamides with enones

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(21), С. 4264 - 4268

Опубликована: Янв. 1, 2024

Herein, we describe a novel metal-free Brønsted acid-catalyzed Ficini [2 + 2] cycloaddition of ynamides with enones under mild reaction conditions, leading to the formation various cyclobutenamides in generally good excellent yields within short times. This work represents first example involved nonmetal-catalyzed enones.

Язык: Английский

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