描述了两种有效的碘介导的经济方法,一种是经济的,而且是一锅法,可用于获得双(咪唑并[1,2 - a ]吡啶-3-基)硫烷和双(咪唑并[1,2 - a ]吡啶-3)。通过使用廉价的硫化钠作为硫源,直接将咪唑-杂环进行氧化均质偶合,在氯仿和乙酸中分别制得[-yl)二硫。这些策略是可扩展的,并且一系列底物以优异的产率提供了其相应的稳定的硫桥联咪唑-杂环。
Metal-free C–N bond formations: one-pot synthesis of pyrido[2′,1′:2,3]imidazo[4,5-c]cinnolines, benzo[4′,5']thiazolo- and thiazolo[2′,3′:2,3]imidazo[4,5-c]cinnolines
An efficient one-pot synthesis of novel pyrido[2′,1′:2,3]imidazo[4,5-c]cinnoline derivatives has been achieved with moderate to good yields, with two C–N bond formations through C–H functionalization of 2-arylimidazo[1,2-a]pyridines. The reaction proceeds via C-3 regioselective hydrazination with diisopropyl azodicarboxylate followed by oxidative N-arylation mediated by phenyliodine(III) diacetate
一种高效的一锅合成新型吡啶并[2',1':2,3]咪唑并[4,5- c ] cinnoline衍生物已实现,具有中等至良好的产率,并通过CH形成了两个C–N键2-芳基咪唑并[1,2- a ]吡啶的官能化。反应通过偶氮二异丙基二异丙基酯的C-3区域选择性酰化进行,然后通过C–H官能化在三氟乙酸中由苯基碘(III)二乙酸酯(PIDA)介导的氧化N-芳基化反应生成吡啶基[2',1':2, 3]咪唑并[4,5- c ] cinnolines。其他imidazoheterocycles如2-芳基苯并[ d ]咪唑并[2,1- b ]噻唑和6-芳基咪唑并[2,1- b对噻唑在无过渡金属和温和条件下进行相似的转化,得到相应的辛啉。
Ring-Opening Reaction of Imidazo[1,2-<i>a</i>]pyridines Using (Diacetoxyiodo)benzene and NaN<sub>3</sub>: The Synthesis of α-Iminonitriles
作者:Amit H. Kalbandhe、Ashish C. Kavale、Nandkishor N. Karade
DOI:10.1002/ejoc.201601480
日期:2017.3.10
Imidazo[1,2‐a]pyridines undergo an unusual ring‐opening reaction to form α‐iminonitriles by using (diacetoxyiodo)benzene and NaN3 under mild conditions.
咪唑并[1,2- a ]吡啶在温和的条件下通过使用(二乙酰氧基碘)苯和NaN 3进行不寻常的开环反应,形成α-亚甲基腈。
Organic-Dye-Catalyzed Visible-Light-Mediated Regioselective C-3 Alkoxycarbonylation of Imidazopyridines by Carbazates
作者:Durgesh Sarothiya、Rajesh T. Bhawale、Umesh A. Kshirsagar
DOI:10.1021/acs.joc.2c01742
日期:2022.11.4
bengal as a photoredox catalyst at roomtemperature has been developed. Biologically important alkoxycarboxylated imidazo[1,2-a]pyridines at the C-3 position as well as coumarins and quinoxalin-2(1H)-ones have been prepared. The present approach has the advantage of having a user- and eco-friendly catalyst, a carbonyl source, as well as extremely mild conditions for direct and regioselective C–H alkoxycarbonylation
已开发出一种温和且环保的可见光介导的咪唑并[1,2- a ]吡啶杂环化合物的区域选择性 C-H 烷氧基羰基化反应,该反应在室温下使用玫瑰红作为光氧化还原催化剂。已经制备了 C-3 位具有重要生物学意义的烷氧基羧基化咪唑并 [1,2 - a ] 吡啶以及香豆素和喹喔啉-2(1 H )-酮。本方法的优点是具有用户友好和生态友好的催化剂、羰基源,以及由可见光作为绿色能源介导的直接和区域选择性 C-H 烷氧基羰基化的极其温和的条件。
Synthesis of imidazole-fused nitrogen-bridgehead heterocycles catalysed by lipase and their antifungal and antimicrobial bioactivity
作者:Manjit Singh、Manisha Malviya、Vijay B. Yadav、Aishwarya Nikhil、Munesh Gupta
DOI:10.1039/d3ra07145f
日期:——
An effective approach for selective C–N bond formation for synthesising imidazo[1,2-a] pyridine-based heterocycles using porcine pancreatic lipase (PPL) as a biocatalyst has been devised.
An ultrasound-assisted expedient protocol has been developed for the synthesis of imidazo[1,2-a]pyridines and imidazo[2,1-b]thiazoles by the C–H functionalization of ketones using a KI/tert-butyl hydroperoxide catalytic system. The reaction takes place in water, a green solvent, and does not require a metal catalyst; it also gives good yields of the products. The method offers numerous noteworthy characteristics
开发了一种超声辅助的简便方案,用于使用 KI/叔丁基过氧化氢催化系统通过酮的 C-H 官能化来合成咪唑并[1,2- a ]吡啶和咪唑并[2,1- b ]噻唑。反应在水这种绿色溶剂中进行,不需要金属催化剂;它还提供了良好的产品产量。该方法具有许多值得注意的特点,包括温和的反应条件、不存在碱、广泛的官能团兼容性和优异的反应产率。此外,它避免了使用昂贵且对空气敏感的化学品,并且可以在环境反应条件下进行。