Catalyst-free ambient temperature synthesis of isoquinoline-fused benzimidazoles from 2-alkynylbenzaldehydes <i>via</i> alkyne hydroamination
作者:Manisha Mishra、Dylan Twardy、Clifford Ellstrom、Kraig A. Wheeler、Roman Dembinski、Béla Török
DOI:10.1039/c8gc02520g
日期:——
route for the synthesis of benzimidazo[2,1-a]isoquinoline has been developed by reacting 2-ethynylbenzaldehyde and related substituted alkynylbenzaldehydes with variously substituted ortho-phenylenediamines and aliphatic amines in ethanol. This method provides a convenient, room temperature, atom-economical, and catalyst-free access to diversely substituted isoquinoline fusedbenzimidazoles. Regioselectivity
通过使2-乙炔基苯甲醛和相关的取代的炔基苯甲醛与各种取代的邻苯二胺和脂肪族胺在乙醇中反应,已开发出一种用于合成苯并咪唑并[ 2,1- a ]异喹啉的有效的环境友好途径。该方法提供了一种方便,室温,原子经济且无催化剂的方法,可轻松获得各种取代的异喹啉稠合的苯并咪唑类化合物。通过X射线晶体学证实了该反应的区域选择性,称为邻苯二胺。发现该反应发生在三个主要步骤(亚胺形成,环化和芳构化)中,并提出了一种机理。
Copper-Catalyzed Inter- and Intramolecular C–N Bond Formation: Synthesis of Benzimidazole-Fused Heterocycles
作者:Sk. Rasheed、D. Nageswar Rao、Parthasarathi Das
DOI:10.1021/acs.joc.5b01396
日期:2015.9.18
Cu (II)-catalyzed, inter/intramolecular C–N bond formation for the synthesis of various benzimidazole-fused heterocycles in a concise manner has been reported. The robustness of this reaction is demonstrated by the synthesis of a series of benzimidazole-fused heteroaromatics (e.g., pyrido[1,2-a] benzimidazole, benzimidazo[1,2-a]quinolines, benzimidazo [1,2-a]pyrazine, benzo[4,5] imidazo[2,1-b]thiazoles)
据报道,一种Cu(II)催化的,分子间/分子内CN键的形成可用于简明合成各种苯并咪唑稠合的杂环。通过一系列苯并咪唑稠合的杂芳族化合物(例如,吡啶并[1,2- a ]苯并咪唑,苯并咪唑[1,2- a ]喹啉,苯并咪唑并[1,2- a ]吡嗪)的合成证明了该反应的稳健性。一锅中直接来自2-氨基杂戊烯类和2-碘芳基硼酸的苯并[4,5]咪唑并[ 2,1- b ]噻唑类化合物 C–N键形成的新型级联方案是通过Chan–Lam型偶联的独特结合然后进行Ullmann型反应来进行的。
Copper-Catalyzed Construction of Benzo[4,5]imidazo[2,1-<i>a</i>]isoquinolines Using Calcium Carbide as a Solid Alkyne Source
作者:Haiyan Liu、Zheng Li
DOI:10.1021/acs.orglett.1c03133
日期:2021.11.5
cross-coupling/nucleophilic addition tandem reactions usingcalciumcarbide as a solidalkynesource, 2-(2-bromophenyl)benzimidazoles as starting materials, and copper as a catalyst is described. The target products can also be synthesized through one-pot three-component reactions of o-phenylenediamines, o-bromobenzaldehydes, and calciumcarbide. Both reaction routes can also be scaled up to gram scale
一种以碳化钙为固体炔烃源,2-(2-溴苯基)苯并咪唑为原料,通过Sonogashira交叉偶联/亲核加成串联反应合成苯并[4,5]咪唑并[2,1- a ]异喹啉的方法材料,并描述了铜作为催化剂。目标产物还可以通过单罐三组分反应合成ö苯二胺类,ø -bromobenzaldehydes,和电石。两种反应路线也可以放大到克级。