Magnetic nanoparticle supported ionic liquid as novel and effective heterogeneous catalyst for synthesis of substituted imidazoles under ultrasonic irradiation

The ionic liquid 1-methyl-3-(3-trimethoxysilylpropyl)imidazolium chloride was immobilized on Fe3O4 nanoparticles and used as an efficient and reusable catalyst for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles at room temperature under ultrasonic irradiation. The immobilized ionic liquid catalysts proved to be effective and easily separated from the reaction media by applying an external magnetic field. This procedure has many obvious advantages compared to those reported in the previous literatures, including avoiding the use of harmful catalysts, reacting at room temperature, high yields, and simplicity of the methodology.