自由基對化學與含螢光基團芳杯之合成與主客化學

Abstract

計畫分兩大部分，第一部分是自由基對化學，第二部分則是含螢光基團的芳杯與雙 芳杯的合成及其主客化學研究。 未來一年我們期望陸續合成雙.咯衍生物14, 15 及咪唑化合物17-20，這些化合物 是自由基對，兩個自由基對甚至是三個自由基對的前驅物，其構造如下圖所示： 在成功合成這些化合物之後，進行照光之後的電子順磁共振光譜(ESR)、溫度變化(Curie Plots)、以及低溫介質霍氏紅外光譜（與本系李遠鵬教授合作）。低溫X-ray 的晶體解析， 以及低溫下照光後的晶體解析，將是此項研最關鑑的證據（將與台大王瑜及清大游靜惠 兩位教授合作）。另外，化合物17a-d 的原料將由中山大學周金興教授提供。我們也將 針對triazoles 16a-c 進行加熱及照光裂解反應，過程中將加入各種烯類及自由基捕捉試 劑（MNP, DMPO），期望能捕捉到反應的雙自由基中區物(請參考表C012 第5 頁)。 第二部分，合成上緣或下緣含Isoxazolines 以及Isoxazoles 螢光基團的芳杯與雙芳杯 化合物及其主客化學研究，包含化合物25-28, 35-38, 44, 45, 47, 48, 以及52-54，至少有 十五大類型的不同組合。針對其中的Isoxazolines (25, 26)以及Isoxazoles(27, 28)化合物 進行開環反應，預期應可獲得多種雙官能基的衍生物，例如1,3-胺基酮以及1,3-氫氧基 酮的芳杯。開環反應將嘗試多種不同試劑，例如Raney Ni, H2/Pt, Mo(CO)6。 完成這些宿主的合成之後將多方嘗試主客化學的探討，測試這些化合物成為金屬離 子偵測器之可行性。採用的偵測方法將包括傳統的紫外可見光光譜儀、穩態及時間分割 螢光光譜量測、氫與碳十三核磁共振光譜，以及X-光單晶晶體解析。

This project includes two major parts: the first part is the study of radical pair chemistry and the second part is the synthesis of isoxazolines and Isoxazoles appended calix[4]arenes and their applications in host guest chemistry. In the following year, we shall complete the synthesis of bispyrroles 14 and 15 and imidazoles 17-20. These compounds are excellent precursors for mono- (triplet), bis- (quintet) and tri-radical pairs (septet); and their structures are shown below: After completing the synthesis of these compounds, we shall take their EPR spectra after photolyzing them for some time. Curie Plots and matrix isolated FTIR (in collaborate with Prof. Lee, Y.-P.) will also be studied. Low temperature X-ray single crystal analysis as well as the analysis after photolysis will provide the most crucial evidences for this radical pair research. This will be collaborated with Prof. Wang, Y. (National Taiwan University) and Yu, C.-H (National Tsing Hua University). Furthermore, the precursors for triarylimidazoles 17a-d will be provided by Prof. Chou, C.-H of National Sun Yat-Sen University. We shall study the pyrolysis and photochemical trapping of triazoles (16a-c) with various olefins and spin trapping agents (MNP or DMPO) in the hope that biradical intermediates can be trapped (cf. p. 5 of C012). The second part is the synthesis of multifunctional calix[4]arenes by the ring opening reactions of isoxazolines, isoxazoles, and heterocycles appended calix[4]arenes. This includes the syntheses of at least 15 types of compounds (25-28, 35-38, 44, 45, 47, 48, and 52-54). Ring-opening reactions on the isoxazolines (25 and 26) and isoxazoles (27 and 28) appended calix[4]arenes should provide us various useful multifunctional derivatives such as beta-amino ketones and beta-hydroxy ketones. Ring-opening reactions will be using (1) Raney Ni, (2) H2/Pt, and (3) Mo(CO)6. After completing the syntheses of these host molecules, we shall explore their application as molecular or ion sensors. Standard methods used in the host-guest chemistry will be carried out for the screening of these novel hosts; and the methods include: UV/vis, steady-state, and time-resolved fluorescence spectroscopy, 1H- and 13C NMR spectroscopy. Finally, X-ray single crystal analysis of these host molecules will be tried whenever possible.