Studied On Synthesis And Characteristic IR Spectra Analysis Of Coumarin Derivatives

Coumarin is the lactone of cis-2-hydroxycinnamic acid. constitute a structural motif shared by many biologically interesting natural compounds that show anti-HIV, anti-tumor, antioxidation or antibacterial properties. They are also widely applied in optical materials, such as fluorescent bleacher, fluorescence probe and laser dye etc.This thesis is mainly composed of three parts:Chapter 1. The classification, application and synthetic methods of coumarins were summarized. In addition, application and basic principles of infrared spectra, the advantages of Fourier transform infrared spectra, qualitative/quantitative analysis, as well as sample preparation techniques in infrared spectroscopy were all concluded in detail.Chapter 2. A series of 3,4-bisubstituted coumarins were designed and synthesized according to literatures. The synthetic method includes amide-directed C-H bond activation, cyclization with diphenyl acetylene and desulphurization. Moreover, the structures of coumarin derivatives were identified with IR, HNMR, CNMR and MS.Chapter 3. After characterization, IR characteristics of the coumarin derivatives were studied. Firstly, we compared the IR spectrum of 3,4-biphenylcoumarin and other coumarin substituted with different groups, to find out effect of different substituents on the IR spectroscopic properties. Finally, we compared the IR spectrum of the coumarin samples prepared by three different methods including pellet method, film method and paraffin oil paste method, to find out the best preparation method.