Synthesis Of Imidazole Compounds Under "Green" Condition

As very important five-membered nitrogen-containing organic compounds, imidazole compounds have very excellent biological activity and pharmacological properties, such as anti-tumor, anti-infective, anti-HTV, anti-inflammatory and so on. In addition, they have wide range of applications in the field of analytical chemistry, biological medicine, agricultural chemicals, organic synthetic chemistry, polymer materials, organic optoelectronic materials. This paper focuses on the research and discussion on the synthesis of an imidazole skeleton, three components as the following:First, because of the unique biological and pharmacological activity, imidazole compounds were paid a lot of attention by chemists and biologists, pharmacists. And its terms have important applications such as materials science, agricultural chemicals and dyes. Since the 19th century, the first synthesis method was reported, subsequently, a large number methods were constantly being discovered. In this chapter, we have a summary about some classical methods and recent research progress on to synthesizing imidazole compounds.Second, iodine-catalyzed synthesis of multi-substituted imidazoles. Through the the previous work, we have developed a green, efficient catalysis by molecular iodine to synthesize 1,2,4-substituted imidazole through [3+2] cycloaddition with benzamidine and ketones. This method uses a green and economy catalyst, no ligand, no alkaline environment, no special atmosphere, simple operation and environmentally friendly.Third, acid promoted to the synthesis of metal-benzo [4,5] imidazo [2,1-a] isoindole and 1,2-dialkyl-2,3-dihydro-benzimidazol under metal-free conditions. This method synthesized a series of compounds containing an imidazole skeleton in the promotion of an acid with o-phenylenediamine and dialdehydes, and no metal involved, mild conditions, green and economy in the whole course of the reaction with prospect application.