Synthesis of benzimidazole and quinoxaline derivatives using reusable sulfonated rice husk ash (RHA-SO3H) as a green and efficient solid acid catalyst
作者:Mahnaz Shamsi-Sani、Farhad Shirini、Masoumeh Abedini、Mohadeseh Seddighi
DOI:10.1007/s11164-015-2075-5
日期:2016.2
In this work, a simple, rapid and efficient method for the preparation of benzimidazoles and quinoxalines from the condensation of o-phenylene diamines with aldehydes and/or 1,2-dicarbonyl compounds in the presence of sulfonated rice husk ash (RHA-SO3H) as an efficient green catalyst is reported. RHA-SO3H can be easily prepared using a readily available organic compound by simple modification of rice husk ash. All reactions are performed under mild reaction conditions with high to excellent yields. The method is applicable to aromatic, unsaturated and hetero aromatic aldehydes. The advantages of this method are short reaction times, milder conditions, easy work-up, solvent-free conditions and catalyst reusability.
在这项工作中,报告了一种简单、快速和高效的方法,通过将邻苯二胺与醛类和/或1,2-二酮化合物在磺化稻壳灰(RHA-SO3H)作为高效绿色催化剂的存在下进行缩合,制备苯并咪唑和喹喔啉。RHA-SO3H可以通过简单的稻壳灰改性,使用一种易于获得的有机化合物轻松制备。所有反应都在温和的反应条件下进行,产率高至优异。该方法适用于芳香族、非饱和和杂环芳香醛。此方法的优点包括反应时间短、条件温和、操作简便、无溶剂条件和催化剂可重复使用。