An efficient green synthesis of highly substituted imidazoles catalyzed by Al-MCM-41 nanoreactors

Al-MCM-41 nanoreactor is found to be a remarkable efficient catalyst for one-pot multicomponent cyclocondensation of benzil, aniline or ammonium acetate and aromatic aldehydes for the synthesis of polysubstituted imidazoles under solvent-free conditions. The reaction was efficiently promoted by nano-Al-MCM-41 and the heterogeneous catalyst was recycled for four runs in this reaction without losing its catalytic activity. The key advantages of this process are operational simplicity, reusable catalyst, shorter reaction time, convenient work-up procedures, avoiding the use of organic solvents and purification of products by non-chromatographic methods. By this advantage, several polysubstituted imidazoles, as pharmaceutical important molecules, can be prepared in high yield and high purity.