Direct Imidation to Construct 1<i>H</i>-Benzo[<i>d</i>]imidazole through Pd<sup>II</sup>-Catalyzed CH Activation Promoted by Thiourea
作者:Qing Xiao、Wen-Hua Wang、Gang Liu、Fan-Ke Meng、Jia-Hua Chen、Zhen Yang、Zhang-Jie Shi
DOI:10.1002/chem.200900154
日期:2009.7.27
method to construct 1H‐benzo[d]imidazole was developed by means of PdII‐catalyzed intramolecular CHactivation starting from easily available N‐phenylbenzimidamide (see scheme). The detailed mechanism studies indicated that a palladacycle monomer or dimer is the key intermediate for this transformation and thiourea was used for the first time to promote the efficiency of CHactivation.
通过Pd II催化的分子内CH活化作用,从容易获得的N -苯基苯甲酰胺开始(见方案),开发了一种新的直接构建1 H苯并[ d ]咪唑的方法。详细的机理研究表明,palladacycle单体或二聚体是该转化的关键中间体,硫脲首次用于提高CH活化效率。
Iron(II) Bromide-Catalyzed Synthesis of Benzimidazoles from Aryl Azides
作者:Meihua Shen、Tom G. Driver
DOI:10.1021/ol801227f
日期:2008.8.7
The identity of the ortho-substituent of an arylazide influences its reactivity toward transition metals. Substitution of a vinyl group with an imine disables rhodium(II)-mediated C-H amination and triggers a Lewis acid mechanism catalyzed by iron(II) bromide to facilitate benzimidazole formation.
Formation of Amidinyl Radicals via Visible-Light-Promoted Reduction of <i>N</i>-Phenyl Amidoxime Esters and Application to the Synthesis of 2-Substituted Benzimidazoles
作者:Gang Li、Ru He、Qiang Liu、Ziwen Wang、Yuxiu Liu、Qingmin Wang
DOI:10.1021/acs.joc.9b01158
日期:2019.7.5
We have developed a new method for the synthesis of 2-substituted benzimidazoles via amidinyl radicals generated by visible-light-promoted reduction of N-phenyl amidoxime esters in the presence of an iridium photocatalyst. This is the first report of the use of N-phenyl amidoxime esters as amidinyl radical precursors, and the first use of substituted benzene rings as amidinyl radical acceptors. This
Oxone-mediated annulation of 2-aminobenzamides and 1,2-diaminobenzenes with<i>sec</i>-amines<i>via</i>imine-<i>N</i>-oxides: new syntheses of 2,3-dihydroquinazolin-4(1<i>H</i>)-ones and 1<i>H</i>-benzimidazoles
An efficient and mild method for the preparation of 2,3-dihydroquinazolin-4(1H)-ones and 1H-benzimidazoles by the oxone-mediated reaction of sec-amines via imine-N-oxides with 2-amino-N-substituted benzamides and 1,2-diaminobenzenes respectively in THF–water (2 : 1) at ambient temperature is described.
Copper(II)-catalyzed oxidative cross-coupling of anilines, primary alkyl amines, and sodium azide is described in the presence of TBHP at moderate temperature. This one-pot multicomponent protocol involves a domino C–H functionalization, transimination, ortho-selective amination, and a cyclization sequence. The broad substrate scope and functional group compatibility are the significant practical features