| Homogeneous Pd (II) complexes are used widely because of its high activity andselectivity. However, because of homogeneous palladium catalysts can not berecycled, as well as catalysts for industrial production are difficult to separate fromthe products, the application of homogeneous Pd (II) complexes in industrialproduction is limited. Immobilization of Pd (II) catalysts on polymers can overcomethis disadvantage. This immobilized Pd (II) catalyst can be removed after reaction bysimple filtration with the advantages of easy separation, recyclablity and easypurification of products; in addition, the the micro-environment of polymer adjacentchain is differ from the micro-environment the solution reaction, such difference willlead to a favorable response rate and the special effects. To immobilize thehomogeneous transition metal catalysts on polymers has become a very meaningfultopic to study in organic synthesis and industrial catalysis.At present, the green organic synthetic chemistry, that is developingenvironmentally friendly methods in organic synthesis, has attracted more and moreattention to the modern chemistry and is becoming an important research. Looking forthe environment-friendly reaction medium is one of an important topic of greenchemistry. Liquid low-molecular-weight polyethylene glycol (PEG) is of greatconcern by researchers as a new type of green organic reaction solvent. PEG has theadvantages of good thermal stability, non-volatile, non-flammable, non-toxic,biodegradable, as well as easy recovery and recycling. In addition, PEG can dissolve alarge number of organic compounds and organic metal complexes. Therefore, PEG asa substitute for organic solvents and homogeneous catalyst carrier has beensuccessfully applied to many organic reactions.This thesis investigatesthe Heck reaction and Sonogashira reaction catalyzed byMerrifield resin-supported palladium catalyst in DMF or PEG-400/H2O.The thesis has three chapters: Chapter One Summary of Heck ReactionThis chapter reviews the latest research progress of Heck reaction from the catalyst,the reaction medium, new technology applied in Heck reaction, non-halogen leavinggroup substrates etc. in recent years.Chapter Two Study on Merrifield Resin-supported Palladium-catalyzed HeckReactionSynthesized Merrifield resin-supported palladium catalyst under Ultrasonicradiation. Studied the catalytic activity as well as recycling situation of the catalyst inHeck reaction. Successfully used the Merrifield resin-supported palladium catalyst inthe Heck reaction in PEG/H2O system, synthesized a series of compounds, obtained amore satisfactory result.Chapter Three Study on Merrifield Resin-supported Palladium-catalyzedSonogashira ReactionSuccessfully used the Merrifield resin-supported palladium catalyst in the Heckreaction in PEG/H2O system, synthesized a series of compounds, obtained a moresatisfactory result.Merrifield resin-supported palladium catalyst is stable in water and air, andhas thermal stability. The catalyst remained considerable catalytic activityrecycling more than 50 with the prospects for industrial applications.
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