Three-component Reaction Based On Trapping Ammonium Ylide And Synthesis Of Two Functional-organic Moleculars

As active intermediates, ylides have been widely used in organic synthesis. Multi-component reactions (MCRs) offer an efficient and convenient entry into constructing diversified and complex molecules. MCRs are considered to be with high atom economy and closely approach to the concept of ideal synthesis. In this thesis, we investigate a new MCR. The reaction is based on trapping active ammonium ylide withβ,γ-unsaturate keto esters. Thus, copper(Ⅱ) catalyzed three-component reactions of diazoacetates, aryl amines andβ,γ-unsaturate keto esters gave coupling product in good yield with high diastereoselective control. Reaction conditions were optimized and the substrate scope was studied. By adjusting the electronic effect and steric effect of substitutions on the components, good diastereoselectivity of the reaction was achieved. Possible reaction pathway leading to the desired three-component coupling product was proposed. Based on several controlling reactions, possibility for the product formation from two component products is excluded. The control experiments support the ylide trapping process, in which, an active ammonium ylide is trapped by the ketoesters. In addition, efforts have been made to achieve asymmetric catalysis of the reaction. Preliminary results are positive for the success of the asymmetric catalysis.Cyclobutene-1,2-diyldimethanol and its precursor dimethyl cyclobut-1-ene-1,2-dicarboxylate are important intermediates in organic synthesis. We optimized the process of the synthesis, and we successfully synthesized dimethyl cyclobut-1-ene-1,2-dicarboxylate in kilogram scale.