One-pot Synthesis Methodology Of Benzithiazole And Benzimidazole Compounds

Benzothiazole and benzimidazole compounds are two types of representative nitrogen-containing heterocycles,which have high biological and pharmacological activities and are widely used in the fields of medicinal chemistry and medicine.In traditional synthesis methods,toxic solvents and various catalysts are often used,which does not conform to the concept of green organic synthesis.In this paper,following the concept of green chemistry,two types of compounds(benzothiazole compounds and benzimidazole compounds)with broad application prospects were studied in one-pot synthesis method under solvent-free and catalyst-free conditions:(1)Using o-aminothiophenol and its derivatives and carboxylic acid compounds as raw materials(Scheme Ⅰ)and o-aminothiophenol and its derivatives and orthoesters as raw materials(Scheme Ⅱ)Synthesis of benzothiazole compounds.Eight differently substituted benzothiazole derivatives were synthesized in a one-pot method.After simple post-treatment,the yield of the target compound can reach more than 90%.At the same time,the reaction temperature,time and feed ratio were optimized,the best reaction conditions were determined,and the possible reaction mechanism was proposed.(2)In the methodological research of benzimidazole compounds,using ophenylenediamine and its derivatives and various substituted aldehydes as raw materials,9 different substituents were synthesized in one pot under solvent-free and catalyst-free conditions The yield of benzimidazole derivatives is good.At the same time,using o-phenylenediamine and formaldehyde as model reaction substrates.In summary,this article discusses the green synthesis methods of benzothiazole and benzimidazole.Compared with traditional synthesis methods,this synthesis method does not use various toxic solvents,transition metals,non-metals,enzymes and other catalysts,avoids environmental pollution and damage,and has high efficiency and speed,mild conditions,simple operation,and atomic utilization.High advantages,in line with the concept of green chemistry.