与众所周知的钯催化的氧化脱氢偶联反应相比,由铜/氧引发的类似转化越来越受到关注。我们研究了通过芳基烷基或烷基烷基酮与2-氨基吡啶的碘化亚铜(I)/三氟化硼醚化物/氧介导的脱氢反应,研究杂芳族咪唑并[1,2- a ]吡啶的新型结构。通过亚胺的形成和氧化性C(sp 3)H官能化一步除去四个氢原子并形成两个新的CN键。
been carried out at room temperature through the functionalization of the sp2 C–Hbond employing Langlois reagent under ambient air. A library of 3-(trifluoromethyl)imidazo[1,2-a]pyridines with broad functionalities have been synthesized regioselectively. This methodology is also applicable to imidazo[2,1-b]thiazole and benzo[d]imidazo[2,1-b]thiazole.
咪唑并吡啶的氧化三氟甲基化反应已在室温下通过使用Langlois试剂对sp 2 C–H键进行官能化来进行。已经选择性地合成了具有广泛功能的3-(三氟甲基)咪唑并[1,2- a ]吡啶的文库。该方法也适用于咪唑并[2,1- b ]噻唑和苯并[ d ]咪唑并[2,1- b ]噻唑。
Copper-Catalyzed Synthesis of Imidazo[1,2-<i>a</i>]pyridines through Tandem Imine Formation-Oxidative Cyclization under Ambient Air: One-Step Synthesis of Zolimidine on a Gram-Scale
A new copper‐catalyzed oxidative cyclization via CH amination between 2‐aminopyridines and methyl aryl/heteroaryl ketones has been developed under ambient air. Imidazo[1,2‐a]pyridines containing a wide range of functional groups have been synthesized from basic and easily available starting materials. This simple, one‐pot reaction protocol is applicable for the direct preparation of zolimidine (a
一种新的铜催化的氧化环化经由Ç ħ胺化2-氨基吡啶和间甲基芳基/杂芳基酮已根据环境空气显影。含有多种官能团的咪唑并[1,2- a ]吡啶是从碱性且容易获得的起始原料合成的。这种简单的一锅法反应方案适用于大规模直接制备唑来咪定(市售的抗溃疡药)。
Nickel-Catalyzed C-H Trifluoromethylation of Electron-Rich Heteroarenes
作者:Yun Wu、Hao-Ran Zhang、Ruo-Xing Jin、Quan Lan、Xi-Sheng Wang
DOI:10.1002/adsc.201600702
日期:2016.11.17
The first example of a nickel‐catalyzed C–H trifluoromethylation of electron‐richheteroarenes, including imidazopyridines, indoles and thiophenes, has been developed with the commercially available and relatively inexpensive industrial raw material iodotrifluoromethane (CF3I) as the trifluoromethylating reagent. The synthetic potential of this method is demonstrated by its successful application to
A direct and efficient protocol for thiocyanation of imidazoheterocycles accompanying with the hydrogen evolution under electrochemical oxidation has been described. Various important thiocyanated and selenocyanated imidazoheterocycles have been constructed through this method in moderate to excellent yields and can easily be scaled up. Further mechanistic studies suggest that aryl radical cation is
<i>N,N</i>-Dimethylacetamide (DMA) as a Methylene Synthon for Regioselective Linkage of Imidazo[1,2-<i>a</i>]pyridine
作者:Anju Modi、Wajid Ali、Bhisma K. Patel
DOI:10.1002/adsc.201600067
日期:2016.6.30
dimerization of two analogous imidazo[1,2‐a]pyridines has been achieved using N,N‐dimethylacetamide (DMA) as solvent cum methylene source. This reaction works with a variety of substituted imidazo[1,2‐a]pyridines giving their products in moderate to good yields. Isotopic labelling experiments revealed that the methylene group in the product originates from the N,N‐dimethyl moiety of DMA.
使用N,N-二甲基乙酰胺(DMA)作为溶剂和亚甲基来源,已实现了两个类似的咪唑并[1,2- a ]吡啶的铜(II)催化的氧化亚甲基桥二聚反应。该反应可与多种取代的咪唑并[1,2- a ]吡啶一起使用,从而使其产物具有中等至良好的收率。同位素标记实验表明,产物中的亚甲基源于DMA的N,N-二甲基部分。