芳杯離子感測器之合成與化學

Abstract

本計畫為期三年共分六個主題: (一)、合成上緣含有不同數目的偶氮基團以及丙烯 基、硫乙醯丙基的芳杯化合物2-5，探討它們如何影響決定金屬離子錯合的能力。下緣 再添加對位雙官能基的酯基或是醯胺基時，這些偶氮芳杯6-8 可以探討所謂的分子變構 性(又稱分子跆拳道)。此外將它們接枝在矽膠的表面也是個重要的目標。(二)、合成具 有掌性的偶氮化合物13-15a,b 然後測量其Circular Dichroism 光譜。因為兩個偶氮基團 在芳杯上緣相距太遠，添加汞離子應該可以將兩者拉近，照光之下可形成所謂的激子。 這些掌性偶氮也可以用紫外可見光光譜或是氫核磁共振光譜來進行掌性辨識之研究。 (三)、合成下緣含isoxazoles 螢光基團的芳杯20-27，利用螢光光譜探討它們對金屬離子 錯合的能力。利用時間解析螢光光譜法可以偵測生命期，從而瞭解它們的淬熄是動態或 是靜態的。另外在二價銅離子存在之下的循環伏安光譜，可以瞭解此類化合物是否發生 氧化還原反應。 (四)、用即合化學(click chemistry)合成下緣含三唑螢光基團的芳杯 33-36a-d，利用螢光光譜探討它們對金屬離子錯合的能力。此外利用即合化學可以將雙 炔芳杯(18、19)接枝到矽膠的表面以達應用價值。(五)、合成下緣含雙螯合基團芳杯或 上緣有偶氮下緣有螢光螯合基團的芳杯38-45，探討它們的分子變構性(allosteric effect)，也就是分階段錯合不同金屬離子或是錯合陽離子然後再錯合陰離子(或是次序相 反)之間的差異性。(六)、合成下緣含三唑香豆素螯合基團芳杯49-51 或三唑香豆素螯合 化合物52-56，利用螢光光譜探討它們對金屬離子錯合的能力。探討主客化學採用的偵 測方法將包括傳統的紫外可見光光譜儀、穩態及時間解析螢光光譜量測、循環伏安法、 氫與碳十三核磁共振光譜、紅外光譜以及X-光單晶晶體解析。

This is a three year project which contains six themes: (1) The synthesis of upper-rim various para-methoxyphenylazo group(s), allyl, and thioacetylpropyl substituted calix[4]arenes 2-5 and the study of their metal ion complexation abilities. The importance of the orientation and numbers of the azo groups will be determined from their binding studies. When the lower-rim of these azo calix[4]arenes is further modified with 1,3-diesters or diamide groups, one can study the so-called allosteric or molecular tae-kwon-do effects. Moreover, the grafting of these azo calix[4]arenas onto the surface of silica gel will be important objectives.(2) Synthesis of chiral azocalix[4]arenas 13-15a,b and their Circular Dichroism measurements. The two azo chromophores are remote from each other in space, however, they may get together, when Hg2+ ion is added, forming exciton coupling. These chiral azo calix[4]arenas can also be used to do chiral recognition using Uv/vis and 1H NMR spectroscopy methods. (3) Synthesis of lower-rim arylisoxazoles substituted calix[4]arenes 20-27 and the study of their metal ion complexation abilities by fluorescence quenching. Data from time resolved fluorescence lifetime measurements will allow us to clarify whether they are static or dynamic quenching. CV of these molecules in the presence and absence of Cu2+ will help to understand whether there involves a redox reaction in the specific quenching of these hosts. (4) Click chemistry synthesis of lower-rim triazole modified calix[4]arenes (33-36a-d) and their metal ion screening by fluorescence spectroscopy. Using the Click chemistry one can graft the mono- or bis-propagylcalix[4]arenas (18 and 19) onto the surface of silica gel which would make these molecules useful for sensor applications. (5) Synthesis of bifunctional calix[4]arenes 38-45 as allosteric (or molecular tae-kwon-do) chemosensors. (6) The synthesis of lower-rim calix[4]arenas with bis-metal ion binding sites or calix[4]arenas with upper rim azo groups and lower rim triazo-coumarin substituents 53-56 and the study of their metal ion complexation abilities by fluorescence quenching. Methodologies used in the host-guest chemistry include: UV/vis, steady-state and time-resolved fluorescence spectroscopy, cyclic voltammetry, 1H- and 13C NMR spectroscopy, FT-IR, and X-ray single crystal analysis.