N-取代的吲哚并[2,3- b ]喹喔啉的合成是通过Ru(II)催化的2-芳基喹喔啉与磺酰叠氮化物的邻位C-H官能化并用2,3-二氯-5进一步氧化而开发的, 6-二氰基-1,4-苯醌一锅。这种双C-N键形成策略为制备一系列生物相关的6 H-吲哚[2,3- b ]喹喔啉衍生物提供了一条新的有效途径,产率高达94%,表明底物适用范围广泛。初步的机理研究表明,连续的 C-N 键形成是通过第一步中五元钌环中间体的形成和第二步中自由基机制的形成进行的。
基于脱氢偶合的反应已成为合成大量杂环的有效途径。本文中,我们报道了两个重要杂环(如喹啉和喹喔啉)的高效,镍催化合成。该催化剂是分子定义的,不含膦,可以在80°C的温和反应温度下运行。两个杂环可以容易地组装经由在较短的反应时间内,分别从2-氨基苄醇/ 1-苯乙醇和二胺/二醇开始的双脱氢偶联。这种使用廉价催化剂的环境友好的合成方案可以与许多其他为制造两个推定的杂环而开发的过渡金属系统相媲美。从机理上讲,仲醇的脱氢遵循干净的拟一级动力学,并表现出相当大的动力学同位素效应。有趣的是,这种催化剂提供了一个将捕获的氢存储在配体主链中,避免形成金属氢化物的例子。在好氧/ O 2氧化作用下,催化剂的氧化形式易于再生,从而使该方案变得环保且易于处理。
Logic design and synthesis of quinoxalines via the integration of iodination/oxidation/cyclization sequences from ketones and 1,2-diamines
作者:Mi Lian、Qi Li、Yanping Zhu、Guodong Yin、Anxin Wu
DOI:10.1016/j.tet.2012.09.056
日期:2012.11
A novel protocol for the synthesis of quinoxalines has been developed from simple ketones and 1,2-diamines. This process underwent a logic approach to bis-substituted quinoxalines via a consecutive iodination/Kornblum oxidation/cyclization in the presence of I2/CuO/DMSO and to mono-substituted quinoxalines via an iodination/cyclization/aromatization in the presence of I2/CuO/K3PO4·3H2O.
从简单的酮和1,2-二胺开发了一种新颖的喹喔啉合成方案。此过程通过连续碘化经历了一个逻辑方式双-取代的喹喔啉/ kornblum氧化反应/环化在我的存在2 /的CuO / DMSO中,并通过以单取代的喹喔啉碘化/环化/芳构化中的我的存在2 /的CuO / K 3 PO 4 ·3H 2 O.
Gold-Catalyzed Synthesis of Glyoxals by Oxidation of Terminal Alkynes: One-Pot Synthesis of Quinoxalines
作者:Shuai Shi、Tao Wang、Weibo Yang、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/chem.201300518
日期:2013.5.17
From terminalalkynes to glyoxals: Terminalalkynes can be oxidized under mild conditions by the use of an N‐oxide in the presence of a gold catalyst. The intermediate glyoxal derivatives can be transferred in a one‐pot procedure to substituted quinoxalines (see scheme).
We have designed a general, inexpensive, and versatile method for the synthesis of (1H-benzo[d]imidazol-2-yl)(phenyl)methanone and the formation of C–N bonds via an aromaticaldehyde and o-phenylenediamine. In the presence of N,N-dimethylformamide/sulfur, (1H-benzo[d]imidazol-2-yl)(phenyl)methanone was obtained; however, in the absence of sulfur, quinoxaline was obtained in 1,4-dioxane. A wide range
我们设计了一种通用,廉价且通用的方法,用于合成(1 H-苯并[ d ]咪唑-2-基)(苯基)甲酮并通过芳香醛和邻苯二胺形成C–N键。在N,N-二甲基甲酰胺/硫的存在下,得到(1H-苯并[ d ]咪唑-2-基)(苯基)甲酮。然而,在不存在硫的情况下,在1,4-二恶烷中获得了喹喔啉。在温和的条件下获得了广泛的喹喔啉和(1 H-苯并[ d ]咪唑-2-基)(苯基)亚甲酮。
A heterogeneous catalytic strategy for facile production of benzimidazoles and quinoxalines from primary amines using the Al-MCM-41 catalyst
This study reports a straightforward heterogeneous catalytic (Al-MCM-41) approach to synthesize nitrogen heterocycle moieties from primaryamines under solvent-free conditions. The Al-MCM-41 catalyst was prepared using a hydrothermal method and characterized by various analytical techniques. The probability and limitations of the catalytic methodology were presented with various substrates. The catalytic
The effective Cp*IrIII‐catalyzed [4+2] tandem cyclization reaction of β‐keto sulfoxonium ylides and o ‐phenylenediamine has been reported for the first time, furnishing monosubstituted quinoxaline and its derivatives with moderate to excellent yield. This novel protocol exhibits broad substrate scope as well as feasibility for late‐stage modification of drug molecules
首次报道了有效的Cp * Ir III催化β-酮基硫代氧鎓基化物和邻苯二胺的串联[4 + 2]环化反应,提供了中等至优异收率的单取代喹喔啉及其衍生物。该新方案展示了广泛的底物范围以及药物分子后期修饰的可行性