[3 + 2]-Cycloaddition of <i>in Situ</i> Generated Nitrile Imines and Acetylene for Assembling of 1,3-Disubstituted Pyrazoles with Quantitative Deuterium Labeling
作者:Vladimir V. Voronin、Maria S. Ledovskaya、Evgeniy G. Gordeev、Konstantin S. Rodygin、Valentine P. Ananikov
DOI:10.1021/acs.joc.8b00155
日期:2018.4.6
methodology for the preparation of 1,3-disubstituted pyrazoles from in situ generated nitrile imines and acetylene is reported. The reactions are performed in a simple two-chamber reactor. One part of the reactor is loaded with hydrazonoyl chloride precursors of active nitrile imine species and a base. The other part is used to generate acetylenefrom CaC2 and water. Partitioning of the reactants improves
A nickel-promoted cascadeannulation reaction for the facile synthesis of 3H-1,2,4-triazol-3-ones from readily available hydrazonoyl chlorides and sodium cyanate has been developed. The transformation occurs through a cascade nickel-promoted intermolecular nucleophilic addition–elimination process, intramolecular nucleophilic addition, and a hydrogen-transfer sequence. The method has been successfully
已经开发了镍促进的级联环化反应,用于从容易获得的酰肼基氯和氰酸钠容易地合成3 H -1,2,4-三唑-3-酮。通过级联镍促进的分子间亲核加成-消除过程,分子内亲核加成和氢转移序列进行转化。该方法已成功应用于血管紧张素II拮抗剂的核心骨架的构建。
Palladium-Catalyzed Cascade Carbonylative Synthesis of 1,2,4-Triazol-3-ones from Hydrazonoyl Chlorides and NaN<sub>3</sub>
A palladium-catalyzed three-component carbonylative reaction for the synthesis of 3H-1,2,4-triazol-3-ones from hydrazonoyl chlorides and NaN3 has been achieved. The reaction presumably proceeds through a cascadecarbonylation, acyl azide formation, Curtius rearrangement, and intramolecular nucleophilic addition sequence. A wide variety of structurally diverse 3H-1,2,4-triazol-3-ones were constructed
已实现了钯催化的三组分羰基化反应,该反应可从酰氯和NaN 3合成3 H -1,2,4-三唑-3-酮。该反应大概通过级联羰基化,酰基叠氮化物形成,Curtius重排和分子内亲核加成序列进行。以中等至优异的产率构建了各种结构多样的3 H -1,2,4-三唑-3-酮。1,2,3,5-三甲酸三苯酯(TFBen)被用作固体和方便的一氧化碳替代物。
Copper(<scp>ii</scp>)-catalyzed coupling reaction: an efficient and regioselective approach to N′,N′-diaryl acylhydrazines
作者:Ji-Quan Zhang、Gong-Bin Huang、Jiang Weng、Gui Lu、Albert S. C. Chan
DOI:10.1039/c4ob02343a
日期:——
An efficient and regioselective copper(ii)-catalyzed coupling reaction of N′-aryl acylhydrazines for the synthesis of N′,N′-diaryl acylhydrazines has been developed.
[3+3] Cycloadditions of Azomethine Ylides with Nitrile Imines for the Synthesis of 2,3,4,5‐Tetrahydro‐1,2,4‐Triazine‐5‐Carboxylates
作者:Limei M. Gao、Xiaomeng M. Wang、Qinglang L. Wei、Kexin X. Su、Renhong H. Huang、Ju Guo、Yongsheng S. Zheng、Jikai K. Liu
DOI:10.1002/ejoc.202200768
日期:2022.9.20
[3+3] cycloaddition of azomethineylides with nitrile imines was established to access unnatural cyclic amino acids containing 1,2,4-triazines. A series of 2,3,4,5-tetrahydro-1,2,4-triazine-5-carboxylates were obtained in moderate to excellent yields under mild reaction conditions.