Sulfate Radical Anion (SO4•–) Mediated C(sp3)–H Nitrogenation/Oxygenation in N-Aryl Benzylic Amines Expanded the Scope for the Synthesis of Benzamidine/Oxazine Heterocycles
摘要:
A transition-metal-free, K2S2O8-mediated intra-molecular, oxidative nitrogenation/oxygenation of C(sp(3))-H in N-aryl benzylic amines followed by oxidation at the benzylic center has been developed for the synthesis of benzamidine/benzoxazine heterocycles, providing an expedient access to quinazolin-4(3H)-ones, N-aryl-2-arylbenzimidazoles, and 4H-3,1-benzoxazin-4-ones. A considerable amount of work dealing with the mechanistic study to understand the crucial intramolecular cyclization step largely favors an iminium ion as the key intermediate.
Iron nitrate/TEMPO-catalyzed aerobic oxidative synthesis of quinazolinones from alcohols and 2-aminobenzamides with air as the oxidant
作者:Yongke Hu、Lei Chen、Bindong Li
DOI:10.1039/c6ra12164k
日期:——
A highly efficient, Iron nitrate/TEMPO-catalyzed approach for the synthesis of quinazolinones has been achieved via a one-pot, tandem aerobic oxidative cyclization of primary alcohols with 2-aminobenzamides. This practical reaction tolerates...
Copper-Catalyzed One-Pot Synthesis of Quinazolinones from 2-Nitrobenzaldehydes with Aldehydes: Application toward the Synthesis of Natural Products
作者:Subrata Sahoo、Shantanu Pal
DOI:10.1021/acs.joc.1c02343
日期:2021.12.17
A novel, efficient, and atom-economical approach for the construction of quinazolinones from 2-nitrobenzaldehydes has been unveiled via copper-catalyzed nitrile formation, hydrolysis, and reduction in onepot for the first time. In this reaction, urea is used as a source of nitrogen for nitrile formation, hydrazine hydrate is used for both the reduction of the nitro group and the hydrolysis of nitrile
首次通过铜催化的腈形成、水解和还原在一个锅中揭示了一种从 2-硝基苯甲醛构建喹唑啉酮的新型、高效和原子经济的方法。在该反应中,尿素用作生成腈的氮源,水合肼用于硝基的还原和腈的水解,大气中的氧气用作唯一的氧化剂。该方法描绘了具有良好官能团耐受性的宽底物范围。此外,该方法还用于合成裂殖菌素、色胺菊酯、phaitanthrin-A、phaitanthrin-B和8 H-喹唑啉[4,3 - b ]quinazolin-8-one。
Three-Component Couplings among Heteroarenes, Difluorocyclopropenes, and Water via C–H Activation
Three-component couplings have been realized for efficiently constructing various nitrogen-containing skeletons via C–H activation, where difluorocyclopropenes have been first identified as coupling partners. Many substrates including sp2 and sp3 C–H substrates were well tolerated, furnishing the corresponding products in good yields. Furthermore, a catalyst-dependent reaction was also developed, enabling
Synthesis of quinazolinones from anthranilamides and aldehydes via metal-free aerobic oxidation in DMSO
作者:Na Yeun Kim、Cheol-Hong Cheon
DOI:10.1016/j.tetlet.2014.02.065
日期:2014.4
A highly environmentally benign protocol for the synthesis of quinazolinones from anthranilamides and aldehydes via aerobicoxidation was developed in wet DMSO. This protocol is operationally simple, exhibits broad substrate scope, and does not need toxic metal catalysts and bases. In addition, the utility of this transformation was further demonstrated by converting the resulting quinazolinones into
Synergistic catalysis on Fe–N<sub>x</sub> sites and Fe nanoparticles for efficient synthesis of quinolines and quinazolinones <i>via</i> oxidative coupling of amines and aldehydes
作者:Zhiming Ma、Tao Song、Youzhu Yuan、Yong Yang
DOI:10.1039/c9sc04060a
日期:——
this paper, we developed a reusable heterogeneous non-precious iron nanocomposite comprising metallic Fe-Fe3C nanoparticles and Fe-N x sites on N-doped porous carbon, which allows for highly efficient synthesis of quinolines and quinazolinones via oxidativecoupling of amines and aldehydes using H2O2 as the oxidant in aqueous solution under mild conditions. A set of quinazolines and quinazolinones
在本文中,我们开发了一种可重复使用的异质非贵铁纳米复合材料,包含金属 Fe-Fe3C 纳米颗粒和 N 掺杂多孔碳上的 Fe-N x 位点,可通过胺和醛的氧化偶联高效合成喹啉和喹唑啉酮在温和条件下以H2O2为氧化剂水溶液。以高产率合成了一系列喹唑啉和喹唑啉酮类化合物,具有广泛的底物范围和良好的官能团耐受性。表征和控制实验表明,金属 Fe 纳米粒子和内置 Fe-N x 位点之间的协同效应是其出色催化性能的主要原因。此外,铁纳米复合材料可以很容易地回收以供连续使用,而催化活性和选择性没有明显损失。这项工作提供了一种方便且可持续的方法来获取药学相关的 N-杂环。