开发了一种氧化剂促进苯并咪唑鎓烷基化物与烯烃的1,3-偶极环加成反应,用于在温和条件下以中等收率制备4 H-吡咯并[1,2- a ]苯并咪唑衍生物。在合适的氧化剂存在下,最商业上可买到的“正构”烯烃,而不是炔烃或“反常”烯烃,可以成功地用作双极性亲和剂。此外,在该程序中,已证明CrO 3 / Et 3 N是比MnO 2或重铬酸四基吡啶钴(II)更为有效的脱氢剂。
开发了一种氧化剂促进苯并咪唑鎓烷基化物与烯烃的1,3-偶极环加成反应,用于在温和条件下以中等收率制备4 H-吡咯并[1,2- a ]苯并咪唑衍生物。在合适的氧化剂存在下,最商业上可买到的“正构”烯烃,而不是炔烃或“反常”烯烃,可以成功地用作双极性亲和剂。此外,在该程序中,已证明CrO 3 / Et 3 N是比MnO 2或重铬酸四基吡啶钴(II)更为有效的脱氢剂。
Molecular Diversity of the Three-Component Reactions of N-Benzylbenzimidazolium Salts, Aromatic Aldehydes, and Active Methylene Compounds
作者:Li Hui、Yu-Xiu Jin、Jin-Xiu Wang、Chao-Guo Yan
DOI:10.1002/ejoc.201101199
日期:2011.12
The three-componentreactions of in-situ-formed N-benzylbenzimidazoliumsalts, aromaticaldehydes, and activemethylenecompounds in the presence of triethylamine showed very interesting moleculardiversity. The reactions with Meldrum's acid or barbiturate in acetonitrile gave a series of the novel zwitterionic salts in high yields. Under similar reaction conditions, the reactions with malononitrile
Synthesis of Fluorinated Indolizines and 4<i>H</i>-Pyrrolo[1,2-<i>a</i>]benzimidazoles via 1,3-Dipolar Cycloaddition of Fluoroalkenes to<i>N</i>-Ylides
作者:Qing-Yun Chen、Kai Wu
DOI:10.1055/s-2003-36246
日期:——
In the presence of K2CO3 and Et3N, pyridinium, quinolinium, isoquinolinium and benzimidazolinium N-ylides, generated in situ from their halides, react with gaseous flouroalkenes [CF2=CFX (1), X = Cl (a), Br (b), CF3 (d)] in DMF under atmospheric pressure in normal glassware at 70 °C to give the corresponding fluorinated indolizines or H-pyrrolo[1,2-a]benzimidazoles via 1,3-dipolar [3+2] cycloaddition. Similar results are obtained with tetrafluoroethene in an autoclave.
Construction of dispirocyclohexyl-3,3′-bisoxindole and dispirocyclopentyl-3,3′-bisoxindole via domino cycloaddition reactions of N-benzylbenzimidazolium salts with 2-(2-oxoindolin-3-ylidene)acetates
作者:Guo-Liang Shen、Jing Sun、Chao-Guo Yan
DOI:10.1039/c4ra13760d
日期:——
Two kinds of spirocyclic oxindoles were selectively synthesized from cycloaddition of N-benzyl-N-phenacylbenzimidazolium salts with two molecules of 2-(2-oxoindolin-3-ylidene)acetates.
straightforward synthesis of highly functionalized pyrroles was achieved by a one-pot reaction between 3-(cyanomethyl)benzimidazolium salts and acetylenic dipolarophiles under reflux in 1,2-epoxybutane. The new pyrroles can also be obtained by a one-pot three-component reaction from substituted benzimidazoles, bromoacetonitrile, and activated acetylenes. The structures of the pyrroles were deduced by
Reaction of 1-alkylbenzimidazolium 3-ylides with ethyl 2,2-dihydropolyfluoroalkanoates
作者:Xue-chun Zhang、Wei-yuan Huang
DOI:10.1016/s0040-4020(98)00728-5
日期:1998.10
In the presence of base, ethyl 2,2-dihydropolyfluoroalkanoates(2) reacted with N-phenacyl(1a-1b), N-acetonyl(1c), N-ethoxycarbonylmethyl(1d) and N-(diethylaminocarbonyl-methyl) benzimidazole bromides(le) in DMF to give the corresponding pyrrolo[1,2-a]quinoxaline derivatives (3) respectively. When (2) was reacted with N-cyanomethyl benzimidazole bromides (1f-1g), fluoroalkyl substituted I-aryl pyrrole derivatives (4) were formed as the major products. (C) 1998 Elsevier Science Ltd. All rights reserved.