Zeolite Assemabled Metals As Catalyst In Heterogeneous Organic Synthesis

Until now,homogeneous catalysis reaction have palyed a very important role in most organic synthesis process,it is an important way for scientfic researchers to contructing a wide range of compounds by homogeneous catalyst.Homogeneous catalysis reaction have been successfully used in many industries,and generally these catalysts have high catalytic activity and selectivity for target products.However,they suffer from some ubiquitous defects;Such as the use of organic ligands improve the catalytic activity,at the same time the reaction conditions become more harsh;And these kind of catalysts are instability at high temperatures,it is diffcult to seperated them from reaction system and recovery for repeat use,make the cost increased.These problems have precluded the widely industrial applications of homogeneous catalysts.It is a key development direction of synthesis chemistry to design a new kind of catalyst which can promote the organic synthesis carried out efficiently.Heterogeneous transition metals catalysts which use solid materials as support have received researchers considerable attention in recent years,for they offer a strategic to overcome these problems.Zeolite is a kind of porous materials which have special channel structure and higher surface area,have been used in catalysis and adsorption industrials.Recent years,with the develop understanding of zeolite structure and properties,more and more new kinds of artificial synthesis zeolite have been successful synthesized,making possible for design a kind of efficient heterogeneous catalyst use zeolite as support and apply it in organic reactions.In this paper,transition metal copper and palladium was assembled with zeolite to prepare new kinds of catalysts which have catalytic activity of transition metal and special characteristics of zeolite,and then use them in organic synthesis reaction.It mainly consists of the following three parts:The first part: The review introduced the wide application of homogeneous and heterogeneous catalysts.The review introduced the structure?properties?synthesis methods and application fields of zeolite.The second part: The transition metal copper doped zeolite Beta was synthesized via an in-situ formation approach,the structure of catalysts have been determined by the technology of X-ray diffraction,nitrogen adsorption-desorption,transmission electron microscope,scanning electron microscope and so on.The catalyst was used in the thioesterification to studied the catalytic activity,we found that this kind of catalyst can promote the synthesis of thioester compounds with high efficient and selectivity,and it also have excellent reusability with good application market.The third part: Palladium nanoparticles supported on mordenite(Pd/MOR)were prepared by tradition ion-exchange method,and then the new kind of catalyst was used to promote the formation of indazole compounds.This catalyst showed higher catalytic activity and efficiency for construct indazoles by the reaction of azobenzenes with unsaturated esters.The Pd/MOR catalyst shows good stability and recyclability,it is an excellent catalyst for the synthesis of indazoles.