Palladium-Catalyzed Coupling of Aldehyde-Derived Hydrazones: Practical Synthesis of Triazolopyridines and Related Heterocycles
作者:Oliver R. Thiel、Michal M. Achmatowicz、Andreas Reichelt、Robert D. Larsen
DOI:10.1002/anie.201001999
日期:2010.11.2
The palladium‐catalyzed intermolecular coupling of aldehyde‐derived hydrazones with chloroazines, followed by oxidative cyclization under mild conditions afforded access to a broad variety of bicyclic heterocyclic scaffolds (see scheme) that have potential for use in drug discovery.
Synthesis of 1,2,4-Triazoles,<i>N</i>-Fused 1,2,4-Triazoles and 1,2,4-Oxadiazoles<i>via</i>Molybdenum Hexacarbonyl-Mediated Carbonylation of Aryl Iodides
protocol has been developed for the synthesis of 1,2,4‐triazoles, N‐fused 1,2,4‐triazoles and 1,2,4‐oxadiazoles using molybdenum hexacarbonyl where, for the first time, molybdenum hexacarbonyl acts as a convenient and reliable solid source of carbon monoxide. This procedure provides an easy access to a library of 1,2,4‐triazole, N‐fused 1,2,4‐triazole and 1,2,4‐oxadiazole derivatives in fair to good
TBAI/TBHP-Catalyzed Synthesis of [1,2,4]Triazolo[4,3-a]pyridines and 3,5-Diaryl-1,2,4-oxadiazoles via Oxidative Cleavage of C=C Double Bond
作者:S. L. Matcha、S. Vidavalur
DOI:10.1134/s1070428021090141
日期:2021.9
Abstract A simple and efficient protocol has been described for the synthesis of [1,2,4]triazolo[4,3-a]pyridines and 3,5-disubstituted-1,2,4-oxadiazoles by reacting 2-hydrazinylpyridine and benzamidoximes, respectively, with styrenes via TBAI/TBHP-mediated oxidative cleavage of C=C bond under ligand- and metal-free conditions.
A facile and efficient approach to access 1,2,4‐triazolo[4,3‐a]pyridines and related heterocycles has been accomplished through condensation of readily available aryl hydrazines with corresponding aldehydes followed by iodine‐mediated oxidative cyclization. This transition‐metal‐free synthetic process is broadly applicable to a variety of aromatic, aliphatic, and α,β‐unsaturated aldehydes, and can
通过容易获得的芳基肼与相应的醛缩合,然后由碘介导的氧化环化反应,可以轻松而有效地获得1,2,4-三唑并[4,3- a ]吡啶和相关杂环。这种无过渡金属的合成方法广泛适用于各种芳香族,脂肪族和α,β-不饱和醛类,并且可以以克为单位方便地进行。
Facile one pot synthesis of N-fused 1,2,4-triazoles via oxidative cyclisation using DDQ
作者:Ashish Bhatt、Rajesh K. Singh、Ravi Kant
DOI:10.24820/ark.5550190.p010.696
日期:——
Abstract A facile and expedient onepotsynthesis of N-fused1,2,4-triazoles from 2-hydrazinopyridines or 2hydrazinopyrazines and aldehydes is described viaoxidative cyclization usingDDQ as a safe and convenient oxidizing agent and polyethylene glycol as recyclable reaction medium. This protocol is effective toward various substrates having different functionalities. The easy recyclability of the