N-Amino pyridinium salts in organic synthesis

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(10), С. 2563 - 2580

Опубликована: Янв. 1, 2023

This review summarizes the synthesis and reactivity of N -aminopyridinium salts, discusses applications in organic synthesis, highlights potential for these reagents to enable novel synthetic disconnections innovations.

Язык: Английский

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Photoinduced Electron Transfer from Xanthates to Acyl Azoliums: Divergent Ketone Synthesis via N‐Heterocyclic Carbene Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(32)

Опубликована: Июнь 12, 2023

Considering the prevalence of alcohols and carboxylic acids, their fragment cross-coupling reactions could hold significant implications in organic synthesis. Herein, we report a versatile method for synthesizing diverse range ketones from acid derivatives via N-heterocyclic carbene (NHC) catalysis. Mechanistic investigations revealed that photoexcited xanthates acyl azoliums undergo single electron transfer (SET) under photocatalyst-free conditions, generating NHC-derived ketyl radicals alkyl radicals. These open-shell intermediates subsequently radical-radical reaction, yielding valuable ketones. Furthermore, this approach can be employed three-component involving alkenes enynes, resulting structurally cross-coupled The unified strategy offers unique opportunity coupling derivatives, accommodating functional groups even complex settings.

Язык: Английский

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C–H Functionalization of Pyridines via Oxazino Pyridine Intermediates: Switching to para-Selectivity under Acidic Conditions

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(28), С. 15581 - 15588

Опубликована: Июль 10, 2023

para-Selective C-H functionalization of pyridines holds a significant value but remains underdeveloped. Site-switchable under easily tunable conditions expedites drug development. We recently reported redox-neutral dearomatization-rearomatization strategy for meta-C-H via oxazino pyridine intermediates. Here, we demonstrate that these intermediates undergo highly para-selective simply by switching to acidic conditions. A broad scope para-alkylated and arylated is prepared through radical as well ionic pathways. These mild catalyst-free methods are applied the late-stage para-functionalization drugs using limiting reagents. Consecutive meta,para-difunctionalization also achieved with complete regiocontrol relying on pH-dependent reactivity pyridines.

Язык: Английский

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Late‐Stage Functionalisation of Pyridine‐Containing Bioactive Molecules: Recent Strategies and Perspectives

European Journal of Organic Chemistry, Год журнала: 2023, Номер 26(16)

Опубликована: Фев. 21, 2023

Abstract Late‐Stage Functionalisation (LSF) is an innovative technique that has been successfully applied to the C−H diversification of pharmaceuticals. However, LSF pyridine ring in drug‐like molecules often unselective. As a result, mixture structurally related products obtained, thus making purification tedious and time‐consuming. This review shines light on recent strategies addressing selectivity issue complex natural or drugs containing moiety. Specifically, we have reviewed efforts reported both academia industries with hope providing guide for elaborated pyridines.

Язык: Английский

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Photoinduced difunctionalization with bifunctional reagents containing N-heteroaryl moieties

Science China Chemistry, Год журнала: 2023, Номер 66(6), С. 1688 - 1700

Опубликована: Май 10, 2023

Язык: Английский

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