Advances in the Synthesis of α-Trifluoromethyl Ketones and Their Application via Defluorinative Reactions

Chinese Journal of Organic Chemistry, Год журнала: 2025, Номер 45(1), С. 86 - 86

Опубликована: Янв. 1, 2025

Язык: Английский

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Cu‐Catalyzed Cascade Cyclization of Ketoxime Acetates and Alkynals Enabling Synthesis of Acylpyrroles

Chinese Journal of Chemistry, Год журнала: 2021, Номер 39(5), С. 1175 - 1180

Опубликована: Янв. 23, 2021

Main observation and conclusion A facile copper‐based catalytic system has been developed to enable efficient cyclization of methylketoximes alkynals. This protocol provides a viable entry synthetically pharmaceutically useful 2‐acylpyrroles with broad range compatible functionalities. Mechanistically, key acyl migration is probably involved that leads the formation N ‐acyl pyrroles or otherwise NH by further hydrolysis. More importantly, present reaction also gives an opportunity realize three‐component pyrrole assembly simple addition carboxylic acid.

Язык: Английский

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tert-Butyl nitrite triggered radical cascade reaction for synthesizing isoxazoles by a one-pot multicomponent strategy

Chemical Communications, Год журнала: 2022, Номер 58(65), С. 9152 - 9155

Опубликована: Янв. 1, 2022

TBN/Na 2 S O 8 -mediated radical cascade reaction of alkenes with aldehydes involving the formation diverse new bonds in one-pot.

Язык: Английский

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Regiodivergent Synthesis of 4‐ and 5‐Sulfenyl Oxazoles from Alkynyl Thioethers

Chemistry - A European Journal, Год журнала: 2024, Номер 30(40)

Опубликована: Май 14, 2024

The regiodivergent synthesis of 4- and 5-sulfenyl oxazoles from 1,4,2-dioxazoles alkynyl thioethers has been achieved. Gold-catalysed conditions are used to favour the formation via β-selective attack nitrenoid relative sulfenyl group. In contrast, 4-sulfenyl formed by α-selective reaction under Brønsted acid same substrates. nature stabilising gold-sulfur interactions have investigated natural bond orbital analysis, showing that S→Au significantly stronger in intermediate favours oxazoles. A kinetic survey identifies catalyst inhibition processes. This study into methods includes development telescoped annulation-oxidation protocols for regioselective access oxazole sulfoxides sulfones.

Язык: Английский

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Copper-catalyzed [4+2] oxidative annulation of α,β-unsaturated ketoxime acetates with ethyl trifluoropyruvate

Chemical Communications, Год журнала: 2022, Номер 58(47), С. 6757 - 6760

Опубликована: Янв. 1, 2022

A novel route for tandem C-N/C-O formation via copper-catalyzed [4+2] oxidative annulation of α,β-unsaturated ketoxime acetates with ethyl trifluoropyruvate to synthesize valuable trifluoromethyl-containing 2H-1,3-oxazines in moderate good yields is developed. This procedure represents the first oxime derivatives activated CO bonds and provides an alternative towards functionalized 2H-1,3-oxazines.

Язык: Английский

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Synthesis of fused 3-trifluoromethyl-1,2,4-triazoles via base-promoted [3 + 2] cycloaddition of nitrile imines and 1H-benzo[d]imidazole-2-thiols

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(35), С. 7095 - 7099

Опубликована: Янв. 1, 2023

Here we report a strategy for the facile assembly of fused 3-trifluoromethyl-1,2,4-triazoles, which are difficult to synthesize using traditional strategies, in 50-96% yields through triethylamine-promoted intermolecular [3 + 2] cycloaddition pathway. This protocol features high efficiency, good functional group tolerance, mild conditions, and easy operation. Furthermore, gram-scale reaction product derivatizations were carried out smoothly illustrate practicability this method.

Язык: Английский

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BF₃·OEt₂-TFAA Mediated Tetra-Functionalization of Amino Acids - Synthesis of Di- and Tri-Substituted 2-Trifluoromethyl Oxazoles in One Pot

Organic Letters, Год журнала: 2020, Номер 22(18), С. 7147 - 7151

Опубликована: Сен. 9, 2020

A highly efficient, TFAA-BF3·OEt2 mediated multicomponent coupling of amino acid, TFAA, and aromatics provides a broad library 2-trifluoromethyl equipped 2,5-disubstituted/2,4,5-trisubstituted oxazoles or N-(trifluoroacetyl)-β-aminoalkyl ketones. This acid tetra-functionalization approach involves amidation (C–N), anhydride (C–O), Friedel–Crafts acylation (C–C), Robinson–Gabriel annulation (C–O) followed by dehydrative aromatization. reaction takes place under operationally simple, mild, metal-free conditions using readily available acids aromatic compounds.

Язык: Английский

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Iron-Catalyzed Cycloaddition of Amides and 2,3-Diaryl-2H-azirines To Access Oxazoles via C–N Bond Cleavage

The Journal of Organic Chemistry, Год журнала: 2021, Номер 86(3), С. 2957 - 2964

Опубликована: Янв. 14, 2021

A novel and efficient iron-catalyzed cycloaddition reaction using readily available 2,3-diaryl-2H-azirines primary amides is reported. wide range of trisubstituted oxazoles could be achieved in good yields with functional group compatibility. In this transformation, two C–N bonds were cleaed new C–O formed.

Язык: Английский

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Copper-catalyzed regioselective [3+2] annulation of malonate-tethered acyl oximes with isatins

Chemical Communications, Год журнала: 2021, Номер 57(27), С. 3379 - 3382

Опубликована: Янв. 1, 2021

A copper-catalyzed regioselective [3+2] annulation of malonate-tethered acyl oximes with isatins was developed, affording valuable 2,3-dihydrooxazole-spirooxindoles in moderate to good yields excellent diastereoselectivity.

Язык: Английский

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Recent Progress in Iodine‐Catalysed C−O/C−N Bond Formation of 1,3‐Oxazoles: A Comprehensive Review

ChemistrySelect, Год журнала: 2021, Номер 6(4), С. 754 - 787

Опубликована: Янв. 26, 2021

Abstract Over the last few decades, iodine has been a stellar catalyst for numerous organic transformations such as C−H activation, hetero‐annulation and coupling reactions. In heterocyclic chemistry, is primarily an economical eco‐friendly that fascinates construction of C−O/C−N bonds via oxidative, radical, electrophilic pathways. Several novel Iodine‐catalyzed methodologies have reported, presenting advances in synthesis with regioselectivity, wide substrate scope excellent yields. Furthermore, feasible protocols implemented to get oxazole annulation literature enormous impact on new synthetic applications. Therefore, this analysis comprises advancements field iodine‐mediated 1,3‐oxazole since 1998. For ease readers, reported categorised based functioning reactions insight into reaction mechanisms highlights.

Язык: Английский

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