Recent advances in transition metal-free annulation toward heterocycle diversity based on the C–N bond cleavage of enaminone platform

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 20(12), С. 2356 - 2369

Опубликована: Янв. 1, 2022

Enaminones and analogous stable enamines are well known as platform building blocks in organic synthesis for the construction of heterocyclic compounds, especially N-heterocycles. To date, enaminones have been successfully employed various 5- or 6- membered heterocycles. Recently, synthetic protocols accomplished by diversity-oriented annulation reactions based on C-N bond cleavage gained notable success. In this review, development transition metal-free product featuring a is reviewed.

Язык: Английский

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A Strategy for Accessing Trifluoromethyl Carbinol-Containing Chromones from o-Hydroxyaryl Enaminones and Trifluoroacetaldehyde/Ketone Derivatives

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(9), С. 5586 - 5596

Опубликована: Апрель 6, 2023

Herein, we present a practical strategy for the direct construction of structurally diverse trifluoromethyl carbinol-containing compounds, especially CF3-substituted tertiary alcohol with chromone derivatives from easily available o-hydroxyaryl enaminones and trifluoroacetaldehyde/ketone under metal-free conditions. This reaction features broad substrate scope good yields is scaled up. Notably, one-pot in two-steps obtained products amidines also developed to provide series multi-substituted pyrimidine bearing two unique hydroxyls one containing functional units.

Язык: Английский

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Pd-Catalyzed Triple-Fold C(sp²)–H Activation with Enaminones and Alkenes for Pyrrole Synthesis via Hydrogen Evolution

Organic Letters, Год журнала: 2021, Номер 23(11), С. 4363 - 4367

Опубликована: Май 20, 2021

The synthesis of NH-free pyrroles via Pd-catalyzed annulation enaminones and alkenes is reported. With the catalysis Pd(II), activation triple C(sp2)-H bonds, including one internal bond in enaminone, has been activated to provide various pyrroles. interesting evolution hydrogen gas from reactions observed by a detector.

Язык: Английский

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Metal-Free Photosynthesis of Alkylated Benzimidazo[2,1-a]isoquinoline-6(5H)-ones and Indolo[2,1-a]isoquinolin-6(5H)-ones in PEG-200

The Journal of Organic Chemistry, Год журнала: 2021, Номер 86(13), С. 9055 - 9066

Опубликована: Июнь 23, 2021

A visible-light-induced decarboxylation reaction was developed for the synthesis of alkylated benzimidazo[2,1-a]isoquinoline-6(5H)-ones and indolo[2,1-a]isoquinolin-6(5H)-ones under metal-free conditions. Impressively, metal catalysts traditionally volatile organic solvents could be effectively avoided.

Язык: Английский

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Preparation of Thiazole-2-thiones through TBPB-Promoted Oxidative Cascade Cyclization of Enaminones with Elemental Sulfur

Organic Letters, Год журнала: 2021, Номер 23(8), С. 3076 - 3082

Опубликована: Март 26, 2021

An unprecedented method for the construction of thiazole-2-thiones via an oxidative cascade cyclization strategy is described. The novel protocol involves simultaneous formation two C—S bonds and a C═S bond on structure enaminones in single operation through C(sp2)—H/C(sp3)—H sulfurations C(sp3)–H thiocarbonylation. This transformation allows efficient synthesis with broad tolerance moderate to excellent yields from simple elemental sulfur.

Язык: Английский

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Copper-catalyzed C–H/N–H annulation of enaminones and alkynyl esters for densely substituted pyrrole synthesis

Chemical Communications, Год журнала: 2022, Номер 58(11), С. 1808 - 1811

Опубликована: Янв. 1, 2022

Herein, the copper-catalyzed annulation of enaminones with alkynyl esters for facile synthesis different pyrroles a 2,3,4,5-tetrasubstituted structure has been developed. With Cu(OAc)2 as only catalyst, tunable 2-vinyl and 2,3-dicarboxyl-functionalized achieved by using terminal internal esters, respectively. The represents first example accessing substituted via direct cascade reactions involving vinylation pyrrole ring formation.

Язык: Английский

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Recent advances in transition metal-catalyzed transformations in N,N-disubstituted enaminones

Tetrahedron Letters, Год журнала: 2023, Номер 130, С. 154766 - 154766

Опубликована: Сен. 26, 2023

Язык: Английский

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Transition metal-free tunable synthesis of 3-(trifluoromethylthio) and 3-trifluoromethylsulfinyl chromones via domino C-H functionalization and chromone annulation of enaminones

Chinese Chemical Letters, Год журнала: 2024, Номер 35(11), С. 109683 - 109683

Опубликована: Март 2, 2024

Язык: Английский

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Silver‐catalyzed Cascade Bis‐heteroannulation Reaction of Enynones and o‐Hydroxyphenyl Enaminones: Access to Highly Functionalized 3‐Furylmethyl Chromones

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(10), С. 2363 - 2369

Опубликована: Март 16, 2024

Abstract A synthetic protocol was developed to synthesize highly functionalized 3‐furylmethyl chromones from enynones and o ‐hydroxyphenyl enaminones via silver‐catalyzed cascade bis‐heteroannulation reaction. This strategy features broad substrate scope good functional group tolerance. Furthermore, the chromone skeleton shows potential application value through further gram‐scale synthesis derivatization.

Язык: Английский

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Selective synthesis of pyridazin-fused chromones and 3-pyridazinyl chromones through intermolecular chromone annulation of o-hydroxyphenylenaminones with aryldiazonium salts

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(14), С. 3906 - 3912

Опубликована: Янв. 1, 2024

A chemodivergent and skeleton-controllable annulation reactions of readily available o -HPEs aryldiazonium salts was described for the synthesis highly functionalized pyridazine-fused chromones with high antiviral activity higher safety.

Язык: Английский

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