A new facile, efficient synthesis and structure peculiarity of quinoxaline derivatives with two benzimidazole fragments
作者:Vakhid A. Mamedov、Nataliya A. Zhukova、Victor V. Syakaev、Aidar T. Gubaidullin、Tat'yana N. Beschastnova、Dil'bar I. Adgamova、Aida I. Samigullina、Shamil K. Latypov
DOI:10.1016/j.tet.2012.10.045
日期:2013.1
A highly efficient and versatile method for the synthesis of quinoxalinederivatives with two benzimidazole fragments have been developed on the basis of the ring contraction of 3-(benzimidazo-2-yl)quinoxalin-2(1H)-one with 1,2-diaminobenzene and its various types of substituted and condensed derivatives. Owing to the inter- and intramolecular processes, involving self association, proton exchange
基于3-(苯并咪唑-2-基)喹喔啉-2(1 H)-与1,2-的环收缩,已开发出一种高效且通用的具有两个苯并咪唑片段的喹喔啉衍生物的合成方法。二氨基苯及其各种类型的取代和稠合衍生物。由于分子间和分子内过程,涉及桥联和相邻碳原子的大多数双-苯并咪唑基喹喔啉信号的几种形式之间的自缔合,质子交换,构象和/或互变异构交换,且NMR光谱中的苯并咪唑片段变宽。苯并咪唑片段与分子的喹喔啉核心之间的共轭作用比喹喔啉衍生物(10c)与其噻二唑[ f ]-(17)和吡咯并[ a ]-(19)环化了衍生物,导致整个分子的平面度更大。
Synthesis of a polymer-capped palladium nanoparticles and its application as a reusable catalyst in oxidative coupling reaction of α-hydroxyketones and 1,2-diamines for preparation of pyrazines and quinoxalines
作者:Mohammad Ali Karimi Zarchi、Seyed Shahab Addin Darbandizadeh Mo Abadi
DOI:10.1007/s13738-018-1290-6
日期:2018.4
support. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of α-hydroxyketones with 1,2-diamines. A few pyrazine derivatives and various quinoxalines are prepared via coupling reaction of α-hydroxyketones and 1,2-diamines in high–excellent yields (81–99%) with short reaction times. The quinoxalines products were characterized by FT-IR, 1H and 13C
在交联的聚(4-乙烯基吡啶)-稳定的Pd(0)纳米粒子[P4-VP]-存在下,使用α-羟基酮和1,2-二胺开发了一种新型的吡嗪和喹喔啉合成方法PdNPs。该催化剂易于使用多种技术进行制备和表征,例如FT-IR和UV-Vis光谱,AAS,TEM,FESEM,EDX分析和XRD。结果证实了钯纳米颗粒在聚合物载体上的良好分散。当该催化剂通过α-羟基酮与1,2-二胺的缩合反应合成喹喔啉时,该催化剂表现出良好的催化活性。通过α-羟基酮与1,2-二胺的偶联反应,可以以短时间的高产率(81-99%)制备一些吡嗪衍生物和各种喹喔啉。FT-IR表征喹喔啉产品,将1 H和13 C NMR光谱和物理性质与已知化合物的文献值进行比较。本方法相对于常规经典方法的优点是快速且非常简单的后处理,并且该催化剂可重复使用多次而其活性没有明显损失。
Ball-milling synthesized hydrotalcite supported Cu–Mn mixed oxide under solvent-free conditions: an active catalyst for aerobic oxidative synthesis of 2-acylbenzothiazoles and quinoxalines
bis(indolyl)methanes was developed using 3,5-bis(trifluoromethyl) phenyl ammonium hexafluorophosphate (BFPHP) as a novel organocatalyst. MATERIALS AND METHODS All of the obtained products are known compounds and identified by IR, 1HNMR, 13CNMR and melting points. RESULT Various products were obtained in good to excellent yields under reaction conditions. CONCLUSION The BFPHP organocatalyst demonstrates a novel class
active quinoxalines and dipyridophenazines were efficiently synthesized in excellent yield and less reaction time using inexpensive, easily recyclable sulfated titania (TiO2–SO42−). TiO2–SO42−, prepared by sol–gel method, was characterized by XRD, FT-IR and SEM techniques to confirm the sulfate loading. TiO2–SO42− has more acidic sites when compared to TiO2 (prepared )and TiO2–P25. Synthesis of quinoxalines