Synthesis Of Bioactive Substances Catalyzed By Supported Lewis Acids

Lewis acid is a commonly used catalyst that exhibits excellent catalytic activity in organic synthesis.However,Lewis acid has many disadvantages as a catalyst,such as too many side reactions,large dosage,corrosiveness,and a large amount of wastewater generated in the post-experimental treatment process.The immobilized Lewis acid catalyst has the advantages of being clean,environmentally friendly,non-toxic or low-toxic,not complicated for post-processing,recoverable,and recyclable.This article mainly discusses the application of Montmorillnoite loaded Lewis acid in the organic synthesis methodology.Taking montmorillonite-loaded Lewis acid as an example,the single factor method is used to investigate its application as a catalyst in the catalytic synthesis of biologically active substances.The main conclusions are as follows:First,using montmorillonite loaded iodine?MMT/I₂?as a catalyst to investigate the optimal reaction conditions of multi-component synthetic imidazole derivatives.The results showed that when MMT/I₂ was used as the catalyst and the amount of 10 mol%of benzyl alcohol and equivalent of DABCO were used as the alkali additive,the ratio of the amount of ammonium acetate,aniline,benzaldehyde,and benzaldehyde was 8.0:2.0:2.0:1.0,reaction at 110?for 16 h,yield up to 91.5%.Second,the influence of montmorillonite loaded ferric chloride MMT/FeCl₃ on the quinoxaline derivatives was investigated,including the catalyst,reaction solvent,time,temperature,catalyst amount and raw material molar ratio.The results showed that the molar ratio of benzoin and o-phenylenediamine was 1.0:1.0 using MMT/FeCl₃ as a catalyst,and the reaction was carried out at 70?with ethanol as the solvent for 8 hours at a yield of 92.8%.Third,using montmorillonite loaded aluminum chloride MMT/AlCl₃ as a catalyst,the use of ultrasound-assisted reaction conditions catalytic synthesis of cyanochalcones,to explore the catalytic reaction of the reaction conditions such as time,temperature,solvent,catalyst and raw material dosage on the target.The results showed that benzoyl acetonitrile and aromatic aldehyde were used as raw materials,the mass ratio of the benzoyl acetonitrile and the aromatic aldehyde was1.0:1.2,the amount of catalyst was 5%of the amount of benzoyl acetonitrile material,ultrasonication was performed at 25?for 15 min,and it was allowed to stand at room temperature the yield can reach 98.8%.Fourth,using Lewis acid---I₂ and proton acid---toluenesulfonic acid?TsOH?as a catalyst,lauric acid and methanol as raw materials,under the conditions of heating catalytic synthesis of methyl laurate.The effects of two catalysts on methyl laurate were investigated.The optimum conditions were as follows:molar ratio of raw material 15:1,amount of iodine was 6%of lauric acid,reaction molar ratio of p-toluenesulfonic acid to iodine was 1.0:2.0,reaction temperature was 60?,reaction time was 90 min,yield was 93.5%.Fifth,montmorillonite loaded with Lewis acid as catalyst has good catalytic activity and shows promising prospects for the synthesis of high-value substances.Montmorillonite loaded with Lewis acid as catalyst has not only milder and simpler conditions?such as lower reaction temperature?than the catalysts studied by previous researchers,but also has high catalytic efficiency,simple post-treatment,low catalyst consumption,low cost,and simple production;meanwhile,it is environmentally friendly,with development prospects.