Design, Synthesis And Optical Properties Of The Λ-type Pyrimidine Derivaties

Two-photon induced fluorescence(TPEF) materials have great potential applications in bio-imaging, three-dimensional optical storage and three-dimensional micro-processing applications, due to its good penetration, high spatial selectivity and resolution, which are the most widely used materials in non-linear field of application. Pyrimidine, one of the four bases of DNA, has good biocompatibility and activity, with a broad research background in biological simulation, electroluminescence and so on. Additionally, it has a high ionization potential and high reactivity, to be easily modified. The current survey on TPEF materials in international material field are reviewed in the dissertation. Seven novel organic chromophores based on pyrimidine have been designed, synthesized and characterized. Single-and two-photon optical properties of the synthesized compounds were investigated both experimentally, and theoretical. Furthermore, The valuable results and conclusions were provided for investigation on TPA materials. The research was introduced as follows:1. Through overlook the research on two-photon fluorescent materials, a brief history and the current development of TPEF materials were reviewed, the feasibility and significance of pyrimidine derivatives with two-photon activifies were elucidated. Based on reviewing, we designed seven target compounds, with a large two-photon absorption cross sections.2. Seven pyrimidine derivatives were synthesized and characterized by IR spectra, Mass spectrum,1H-NMR spectra, 13C-NMR spectra and Elemental analysises (C, H, N). the single-crystal structure of two compounds were analyzed. Of these, compound Z7 crystalizes in P21/c space group, compound Z10 in non-centrosymmetric space group P212121, showing network structure.The crystal should exhibit second harmomic generation response.3. The linear and nonlinear optical properties of pyrimidine derivatives were investigated. The target compounds in different solvents has a high fluorescence quantum yield, which decrease with the electron withdrawing ability of substituent attached to the pyrimidine 2 unit. The results showed that nonlinear response of the compounds increase with the electron withdrawing ability of substituent attached to pyrimidine at 2 unit. Theoretical caclulation show that the main peaks are from the HOMO to LUMO orbital of the transition, that is, the donor (D) and acceptor (A), which also verified the D-Ï€-A-Ï€-D configuration can enhance and improve the two-photon response.