Copper-Catalyzed Oxidative Amination of Benzoxazoles via C−H and C−N Bond Activation: A New Strategy for Using Tertiary Amines as Nitrogen Group Sources
method for oxidative amination of azoles with tertiary aminesviacopper-catalyzed C−H and C−Nbond activation has been developed. This protocol can be performed in the absence of external base and only requires atmospheric oxygen as oxidant. The catalyst system is very simple and efficient, which opens a new way for using tertiary amines as nitrogen group sources for C−Nbondformation reactions.
A Metal-Free Amination of Benzoxazoles – The First Example of an Iodide-Catalyzed Oxidative Amination of Heteroarenes
作者:Tanja Froehr、Christian P. Sindlinger、Ulrich Kloeckner、Peter Finkbeiner、Boris J. Nachtsheim
DOI:10.1021/ol201439t
日期:2011.7.15
An efficient transition-metal-free amination of benzoxazoles has been developed. With catalytic amounts of tetrabutylammoniumiodide (TBAI), aqueous solutions of H2O2 or TBHP as co-oxidant and undermild reaction conditions, highly desirable 2-aminobenzoxazoles were isolated in excellent yields of up to 93%. First mechanistic experiments indicate the in situ iodination of the secondary amine as the
已经开发出有效的无过渡金属苯并恶唑胺化的方法。用催化量的四丁基碘化铵(TBAI),H 2 O 2或TBHP水溶液作为助氧化剂,并在温和的反应条件下,以高达93%的优异收率分离出了非常理想的2-氨基苯并恶唑。最初的机械实验表明,仲胺的原位碘化是假定的活化方式。
Iodine-Catalyzed Amination of Benzoxazoles: A Metal-Free Route to 2-Aminobenzoxazoles under Mild Conditions
作者:Manjunath Lamani、Kandikere Ramaiah Prabhu
DOI:10.1021/jo201402a
日期:2011.10.7
route of oxidative amination of benzoxazole by activation of C–H bonds with secondary or primary amines in the presence of catalytic iodine in aqueous tert-butyl hydroperoxide proceeds smoothly at ambient temperature under neat reaction condition to furnish the high yield of the aminated product. This user-friendly method to form C–Nbonds produces tertiary butanol and water as the byproduct, which are
Copper-Catalyzed Electrophilic Amination of Benzoxazoles via Magnesation
作者:Sangback Lee、Yunmi Lee
DOI:10.1002/ejoc.201900335
日期:2019.5.26
A mild and efficient method for the synthesis of 2‐aminobenzoxazoles through a Cu‐catalyzed electrophilicamination of benzoxazole derivatives with O‐benzoyl hydroxylamines by direct magnesation has been developed.
Cooperative Catalysis with Aldehydes and Copper: Development and Application in Aerobic Oxidative CH Amination at Room Temperature
作者:Yinjun Xie、Bo Qian、Pan Xie、Hanmin Huang
DOI:10.1002/adsc.201200944
日期:2013.5.3
formation of an aminal, hydrolysis of the aminal to generate the copper‐amide species, subsequent CH amination and re‐oxidation of copper(I) to copper(II) by oxygen. It not only provides an efficient method to realize the oxidative CH amination of benzoxazoles with free amines at room temperature, but also paves the way for establishing new CN bond formation reactions by using this efficient cooperative