Investigation On Novel Microwave-assisted Synthesis Method Based On MCM-41 Microreactor

The synthesis methodology plays an important role in synthetic chemistry. The organic reaction in the microreactors (nano-reactors) was different from that in solution, which was better selectivity and higher reaction rate and attract more and more attention of organic chemists. The microreactors include: cyclic ligands hole (cyclodextrins, crown ethers, calixarenes, etc.), molecular aggregates (micelles, reverse micelles, LB films, vesicles, liquid crystal, etc.) and porous solid (MCM-41s, aluminum oxide, clay, etc.). In many published examples, microwave radiation accelerated chemical tansformations significantly, microwave-assisted organic synthesis was one of the focus of organic chemistry in recent years. However, most research was still limited to the applications of microwave in organic synthesis. No microreactors based on microwave-assisted synthesis method was found. In this article, a new method of microwave assisted synthesis based on MCM-41s microreactors were put forward for the first time, which combines microwave radiation with microreactors of MCM-41s. And the synthesis of benzofuran-2(3H)-ketone derivatives was selected as modeling reaction. Microreactors lactone reaction at microwave radiation and MCM-41 family microreactors was investigated through the rational discussion of the experimental design.The main research results are as follow:In the first part, the benzofuran derivatives was synthesised under conventional heating and microwave irradiation. The reaction conditions including temperature, reaction time, microwave radiation were investigated and the optimized conditions were obtained.In part two, by comparison of the yield in solution with and that in MCM-41s microreactors, the law of benzofuran-2(3H)-one derivatives reaction in MCM-41s microreactors was obtained. It is confirmed that in MCM-41s microreactor the yield was significantly higher than that under solution conditions. After imposed by microwave, the production rate was further increased. The reaction was different in MCM-41s microreactors with different pore sizes and different functional groups.In chapter III, by comparison of the yields in solution and in MCM-41 microreactors, the law of the reaction of synthesis of benzofuran-2(3H)-ones derivatives in MCM-41 microreactor was obtained; the effect of microwave radiation was discussed. It was confirmed that the yield in MCM-41 microreactor was significantly higher than that under solution conditions, in addition, the yield of the reaction in MCM-41 microreactor could be improved under microwave radiation, resulting from the microreactor chamber effect and the selectivity of microwave heating.In the fourth chapter, by comparison of the yields in solution and in MCM-41-(CH₂)₃Cl microreactor, the law of reaction of synthesis of benzofuran-2(3H)-ones derivatives in MCM-41-(CH₂)₃Cl microreactor was obtained. It was confirmed that the yield in MCM-41-(CH₂)₃Cl microreactor was significantly higher than that under solution conditions. In addition, the yield of the reaction in MCM-41 microreactor could be improved under microwave radiation. The influence of aperture size and functional group on the microreactor chamber was discussed.In the fifth chapter, by comparison of the yields in solution and in MCM-41-(CH₂)₃NH2 microreactor, the law of reaction of synthesis of benzofuran-2(3H)-ones derivatives reaction in MCM-41-(CH₂)₃NH2 microreactor was obtained. It was confirmed that the yield in MCM-41-(CH₂)₃NH2 microreactor was significantly higher than that under solution conditions again. In addition, the yield of the reaction in MCM-41 microreactor could be improved under microwave radiation. The influence of aperture size and functional group on the microreactor chamber was discussed.