Nickel-Catalyzed Heteroarenes Cross Coupling via Tandem C–H/C–O Activation
作者:Ting-Hsuan Wang、Ram Ambre、Qing Wang、Wei-Chih Lee、Pen-Cheng Wang、Yuhua Liu、Lili Zhao、Tiow-Gan Ong
DOI:10.1021/acscatal.8b03436
日期:2018.12.7
Inert aryl methyl ethers as coupling components via C–O activation have been established with a Ni catalyst for C–H activation of heteroarene. The key to simultaneous C–H/C–O bond activation is the use of sterically demanding o-tolylMgBr. The protocol is effective for a wide scope of substrates including naphthyl methyl ethers, anisoles, and a variety of other heteroarene derivatives. Detailed mechanistic
Electrochemical Synthesis of Benzimidazoles via Dehydrogenative Cyclization of Amidines
作者:Huai‐Bo Zhao、Jin‐Liang Zhuang、Hai‐Chao Xu
DOI:10.1002/cssc.202100254
日期:2021.4.9
sustainable methodologies for the synthesis of N‐heterocycles is a constant focus of organic synthesis. Herein an electrochemical method is reported for the synthesis of benzimidazoles through dehydrogenative cyclization of easily available N‐aryl amidines. The reactions were conducted under simple constant current conditions in an undivided cell without need for catalysts, chemical oxidants, or additives, and
Gold nanoparticles supported on titanium dioxide: an efficient catalyst for highly selective synthesis of benzoxazoles and benzimidazoles
作者:Lin Tang、Xuefeng Guo、Yu Yang、Zhenggen Zha、Zhiyong Wang
DOI:10.1039/c4cc01822b
日期:——
A highly efficient and selective reaction for the synthesis of 2-substitutedbenzoxazoles and benzimidazoles catalyzed by Au/TiO2 has been developed via two hydrogen-transfer processes. This reaction has a good tolerance to air and water, a wide substrate scope, and represents a new avenue for practical C-N and C-O bond formation. More importantly, no additional additives, oxidants and reductants are
Aerobic Oxidative Coupling of Amines by Carbon Nitride Photocatalysis with Visible Light
作者:Fangzheng Su、Smitha C. Mathew、Lennart Möhlmann、Markus Antonietti、Xinchen Wang、Siegfried Blechert
DOI:10.1002/anie.201004365
日期:2011.1.17
Coupling on sunshine: A simple and efficient synthesis of benzoxazoles, benzimidazoles, and benzothiazoles is realized through a one‐pot preparation driven by a photocatalyticcascade reaction. Carbon nitride and visiblelight are employed to achieve this metal‐free aerobic oxidation of amines to imines (see scheme; mpg‐C3N4=mesoporous graphite carbon nitride).
阳光下的耦合:通过光催化级联反应驱动的一锅法制备,可实现苯并恶唑,苯并咪唑和苯并噻唑的简单有效合成。氮化碳和可见光可用于实现胺向亚胺的无金属需氧氧化(请参阅方案; mpg-C 3 N 4 =中等石墨氮化碳)。
Synthesis of 2-substituted benzimidazoles and benzothiazoles using Ag2CO3/Celite as an efficient solid catalyst
作者:Ebrahim Soleimani、Mohammad Mehdi Khodaei、Hossein Yazdani、Parisa Saei、Javad Zavar Reza
DOI:10.1007/s13738-015-0592-1
日期:2015.7
An efficient and simple approach for the synthesis of 2-substitutedbenzimidazoles and benzothiazoles through a coupling of 1,2-phenylenediamines and 2-aminothiophenols with variety of aryl aldehydes in ethanol at 70 °C using Ag2CO3/Celite as solid catalyst is described. The procedure features short reaction time, excellent yields and simple workup.
在20°C的乙醇中,使用Ag 2 CO 3 / Celite作为固体催化剂,通过1,2-苯二胺和2-氨基苯硫酚与各种芳基醛的偶合,合成2位取代的苯并咪唑和苯并噻唑的有效而简单的方法是描述。该程序的特点是反应时间短,产率高,后处理简单。