Synthesis of quinoxalines accelerated by a new nanocatalyst based on ionicliquid stabilized on TiO۲ and Kaolin

Ionic liquids (ILs) have been recognized as appropriate green catalysts/solvents in organictransformations. This is due to their remarkable properties such as negligible vapor pressure,thermal stability over a wide temperature range,non-flammability and ability to dissolve organicand inorganic compounds. Nevertheless, several drawbacks of ILs such as high cost, highviscosity, large consumption and separation difficulties restrict their large-scale applications.However, these issues can be solved efficiently by using supported ionic liquids (SILs) preparedby the immobilization of ILs on solid supports. SILs offer several advantages such as ease ofhandling, minimizing the amount of IL utilized in the reactions and simple separation, and reuse.In this regard, various supports have been used to immobilize ILs, including silica, clays and metaloxides. In the meantime, natural clays such as kaolin have received more attention due to theiroutstanding physical and chemical properties, abundance in nature around the world, low cost, andenvironmental advantages. Also, TiO۲ nanoparticles due to their low cost, easy synthesis and highthermal stability can efficiently be used for this purpose. In this project, we want to make a catalystby the immobilization of an the ionic liquid on a solid substrate prpared from TiO۲ and Kaolin thatcan be easily separated from the reactions. The simple preparation of the catalyst, short reactiontime, high efficiency, and the ability to recycle the catalyst are the main advantages of this method.Also, this catalyst is effective in increasing the speed of the synthesis of quinoxalines orbenzopyrazines, as very important groups of nitrogen-containing compounds.

کلیدواژه ها:

TiO۲ ، Kaolin ، Ionic liquid ، Nano-catalyst ، Quinoxalines