Cu(II)-mediated annulation of 4-hydroxycoumarins with propargyl carbonates: Facile access to furo[3,2-c]coumarin scaffold

Tetrahedron Letters, Год журнала: 2023, Номер 128, С. 154697 - 154697

Опубликована: Авг. 9, 2023

Язык: Английский

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Enantioselective Alkynylation of Pyrazole-4,5-diones with Terminal Alkynes Catalyzed by Copper/PyBisulidine

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(19), С. 13645 - 13654

Опубликована: Сен. 8, 2023

A copper/PyBisulidine-catalyzed enantioselective alkynylation of electrophilic pyrazole-4,5-dione with terminal alkynes has been developed. Chiral tertiary propargylic alcohols bearing the pyrazolone motif were prepared yields (up to 99%) and enantioselectivities 99% ee). The prominent feature this protocol includes its mild reaction conditions good stereoselectivities. nonlinear effect study showed that catalytically active specie was a monomeric catalyst excess copper activated through π-system.

Язык: Английский

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Recent Synthesis of Mono‐ & Bis‐Pyranopyrazole Derivatives

ChemistrySelect, Год журнала: 2024, Номер 9(8)

Опубликована: Фев. 22, 2024

Abstract Pyranopyrazole is an important structural unit in heterocyclic chemistry and useful pharmaceutical agrochemical industries. The pyranopyrazole‐based compounds are known the agricultural industry as herbicides, fungicides, insecticide agents medicinal fields antimicrobial, anticancer, antiHIV agents. Despite its wide range of applications, synthesis pyranopyrazole has several limitations such cost reagents, potential environmental risks, harsh reaction conditions, longer times, laborious workup procedures, unsatisfactory yields. However, many studies have been recently reported on pyranopyrazoles using mild, green, environmentally friendly methods that also give higher Different catalysts conditions for four, three, two components. Among these, four‐component commonly by benzaldehyde, hydrazine derivatives, ethyl acetoacetate malononitrile due to commercial availability stability reagents. This review summarized recent i. e ., mono ‐ bis ‐pyranopyrazole derivatives via four‐, three‐ two‐component‐based reactions. Mono varied number units contributed play role increasing binding interaction biological activities beneficial

Язык: Английский

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Copper‐Catalyzed α,β‐Regioselective (2+4) Cycloaddition of Propargylic Esters

European Journal of Organic Chemistry, Год журнала: 2023, Номер 26(46)

Опубликована: Сен. 26, 2023

Abstract A copper‐catalyzed α,β‐regioselective (2+4) cycloaddition of propargylic esters with o ‐hydroxyphenyl substituted secondary phosphine oxides (SPOs) was established, which afforded a series phosphorus‐containing six‐membered heterocycles in high yields. This reaction represents the first (2+n) via intermediates copper‐allenylidenes, will enrich chemistry and copper‐allenylidenes. Moreover, this work also application SPOs as 1,4‐dinucleophiles cycloadditions, provides useful protocol for synthesis potential bioactivity.

Язык: Английский

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Copper‐Catalyzed Formal [4+2] Cycloaddition of Ethynylethylene Carbonates for the Construction of 3,4‐Dihydro‐2H‐benzo[b][1,4]oxazines

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(25)

Опубликована: Апрель 9, 2024

Abstract A formal [4+2] cycloaddition reaction of ethynylethylene carbonates and 2‐aminophenols has been developed for the synthesis 3,4‐dihydro‐2 H ‐benzo[ b ][1,4]oxazines bearing quaternary carbon atoms. The features mild conditions, good functional group compatibility yields. Furthermore, when using chiral PyBox ligand, this strategy could also achieve asymmetric ][1,4]oxazines. Application studies indicated that hydroxymethyl final products was an excellent can be further modified easily.

Язык: Английский

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Five-membered ring systems: with more than one N atom

Progress in heterocyclic chemistry, Год журнала: 2023, Номер unknown, С. 281 - 332

Опубликована: Янв. 1, 2023

Язык: Английский

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Five-membered ring systems: with O and S (Se, Te) atoms

Progress in heterocyclic chemistry, Год журнала: 2023, Номер unknown, С. 333 - 349

Опубликована: Янв. 1, 2023

Язык: Английский

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Six-membered ring systems: With O and/or S atoms

Progress in heterocyclic chemistry, Год журнала: 2023, Номер unknown, С. 493 - 568

Опубликована: Янв. 1, 2023

Язык: Английский

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