Transition Metal Catalyzed Coupling Reactions Using Phenylacetylene As A Substrate

Organic synthesis, breaking the old organic bonds and forming the new bonds, is the process of preparing complex organic compounds through the formation of carbon-carbon bond and functional group transformation of small molecular compounds. Generally speaking, the electrophilic saturated carbon (sp3) can form corresponding carbon-carbon, carbon-heteroatom bonds directly with the nucleophilic carbon, nitrogen, oxygen, sulfur atoms, while the direct bond formation of electrophilic unsaturated carbon (sp or sp2) is relatively difficult. In recent years, as a new approach to form the bond between the unsaturated carbon and nucleophilic carbon or heteroatom, the Cross-Coupling Reactions and Conia-Ene Reactions were developed.In2003, Li Chao-Jun’s group reported the gold-catalyzed three-component coupling reaction for the first time. Then, various three-component coupling reactions catalyzed by copper, silver, gold, indium and gold nanoparticles, copper nanoparticles, iron nanoparticles, and so on were reported in diverse literatures.In this thesis, we studied the silver-nanoparticles catalyzed three-component coupling reaction which can be carried out without the nitrogen atmosphere since silver nanoparticles are stable in the air. Through the optimization of the reaction conditions, we confirmed that the reactions can be carried in chloroform at room temperature. Subsequently, a variety of propargylamines are prepared from various aldehydes, alkynes, and amines using the optimized reaction conditions to expand the scope of the substrates, and satisfactory results were achieved. After simple purification, the catalyst can be reused several times without significant loss of yield, which indicates that the activity of the catalyst is not significantly reduced. The silver nanoparticles can be readily synthesized and separated, and the reactions are rapid and efficient under wild conditions. This method meets the requirements of green chemistry, and it can be applied for the synthesis of propargylamines.On the other hand, from1980s, scientists were working on metal-catalyzed Conia-Ene reactions. They developed various metal catalysts such as aluminum, palladium, gold, indium and so on to catalyze the Conia-Ene reactions, and achieved various degrees of success. In this thesis, we tested copper(Ⅰ) compounds catalyzed Conia-Ene reactions. The reaction was carried out under argon atmosphere since the copper(Ⅰ) compounds can be easily oxidized in the air. After optimization, the target product can be obtained by using CuOTf as a catalyst, and AgBF4as an additive, at80℃in1,2-dichloroethane. However, the reaction yield is still low, and it is not beneficial to expand the scope of the substrates. Therefore, we need to find better conditions to improve the yield, and the related work is still in progress.