Synthesis Of MCM-41-Supported Sulfur Palladium(O) Complexes And Their Applications In Organic Synthesis

This dissertation consists of two parts:Part one: A MCM-41 -supported mercapto palladium(0) complex has been prepared from γ-mercaptopropyltriethoxysilane via immobilization on MCM-41, followed by reacting with Me₃SiCl and palladium chloride, then the reduction with hydrazine hydrate. It was found that this palladium(0) complex has not only high activity and stereoselectivity for arylation reaction of conjugated alkenes with aryl iodides and activated aryl bromides, but also can efficiently catalyze the Sonogashira coupling and the Suzuki coupling reactions. This palladium(0) complex catalyst can be easily recovered from the products and reused many times without loss of activity.Part two: A MCM-41-supported thioether palladium(0) complex has beensynthesized from 3-(2-cyanoethylsulfanyl)propyltriethoxysilane via immobilization on MCM-41, followed by reacting with with Me₃SiCl and palladium chloride, and then the reduction with hydrazine hydrate. It was found that this complex has high activity for arylation reaction of conjugated alkenes with unactivated bromoarenes and for the Suzuki coupling reaction of aryl halides with ArB(OH)₂. It also provided a mild route for the copper-free Sonogashira coupling of aryl iodides with terminal acetylenes in water under air. This thioether palladium(0) complex can be easily recovered from the products and reused many times without loss of activity.