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 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。
Synthesis of imidazo and benzimidazo[2,1-a]isoquinolines by rhodium-catalyzed intramolecular double C–H bond activation
The rhodium-catalyzed intramolecular direct arylation of imidazole and benzimidazole derivatives via double C–H bond activation is described. This approach provides new access to a wide range of imidazo and benzimidazo[2,1-a]isoquinoline derivatives in moderate to high yields. This reaction provides an alternative method to the known Pd-catalyzed intramolecular oxidative cross-coupling reactions.
铑催化的分子内芳基直接芳基化 咪唑和苯并咪唑衍生物通过双CH键活化。该方法以中等至高收率提供了广泛的咪唑和苯并咪唑并[2,1- a ]异喹啉衍生物的新途径。该反应为已知的Pd催化的分子内氧化交叉偶联反应提供了替代方法。