Synthesis of Quinoxaline Derivatives using Sulfonic Acid Functionalized Imidazolium Salts as Highly Efficient and Reusable Bronsted Acidic Ionic Liquids Catalysts under Solvent-free Conditions

Abstract

A simple, highly efficient and green procedure for the condensation of aryl and alkyl 1,2-diamines with α-diketones in the presence of catalytic amount of sulfonic acid functionalized imidazolium salts (SAFIS) is described. Using this method, quinoxaline derivatives as biologically interesting compounds are produced in high to excellent yields and short reaction times. Environmentally benign, simple methodologies, easy workup procedure, clean reaction, short reaction time, high yield and easy preparation of the catalysts are some advantages of this work. In this work, some sulfonic acid functionalized imidazolium salts (SAFIS), as a new category of ionic liquids, are synthesized by eco-friendly and simple procedures, and used as highly efficient and reusable catalysts to promote the following one-pot organic transformations under solvent-free conditions.