偶氮類及自組裝類calix[4]arenes之合成研究與前者的金屬離子感測研究

Abstract

本論文主要研究方向分為兩部份，分別為偶氮calix[4]arene之合成與感測研究，以及自組裝類calix[4]arene之合成。 首先，合成出七種偶氮calix[4]arene衍生物42、43、44a-b、45a-b及47，分別進行紫外可見光譜之量測，依據Beer-Lambert Law求得莫耳吸收係數，並針對十四種過氯酸鹽金屬進行初步篩選，結果顯示以感測過渡金屬的靈敏度最好，尤其以跟Hg2+錯合後的溶液顏色變化最為明顯，且造成最大吸收波長紅位移現象。利用Benesi-Hildebrand plot計算偶氮calix[4]arene與Hg2+錯合之結合常數 Ka，以化合物44a對Hg2+的錯合能力最佳。經由氫核磁共振光譜滴定實驗及紅外光譜之測量，推測化合物42、43及45a與Hg2+錯合時，發生了azophenol-quinone-hydrazone互變異構化現象，進而推測出42•Hg2+及43•Hg2+之錯合型態示意圖。 其次，成功合成具硫醇修飾calix[4]arene 49及50，期望未來利用硫-金鍵結形成自組裝薄膜，進行相關表面化學之測量，另一方面也欲合成具有胺基修飾calix[4]arene，使其與3,3-dithiobis(propionic acid N-hydroxysuccinimide ester) 鍵結形成具有長鏈之化合物，以利於在金表面上的排列，但遺憾未能成功合成出目標物，期望未來不同合成策略能完成此目標。

In this thesis, the synthesis of azo- and self-assembled-calix[4]arene are described. Furthermore, the metal ions sensing studies of the seven newly synthesized azocalix[4]arene are discussed . First of all, a series of new azocalix[4]arene 42, 43, 44a-b, 45a-b and 47 were synthesized. Before screening with metal ions, the extinction coefficients of azocalix[4]arenes were determined by the Beer-Lambert Law. Fourteen different metal perchlorates was screened by azocalix[4]arenes 42, 43, 44a-b, 45a-b and 47 using UV/vis spectroscopy as a tool. The results revealed that azocalix[4]arenes are sensitive to transition metal ions with large bathochromic shifts in λmax. Benesi-Hildebrand plots were used to determine the association constants of azocalix[4]arenes with Hg2+. Possible complexation models of 42•Hg2+ and 43•Hg2+ were proposed based on the information obtained from 1H-NMR titration experiments and the IR spectroscopy measurements. The results also implied that there is an equilibrium between metal complexation-induced release of protons from the azophenol to the quinone-hydrazone tautomer. The synthesis of calix[4]arene with self-assembled functional groups are studied next, where thiocalix[4]arene 49 and 50 were synthesized. We expected that they may be applicable on the gold surface by a S-Au bond formation. In order to arrange calix[4]arenes well on the gold surface, we also wish to attach amino group on the upper rim of calix[4]arene for binding with 3,3-dithiobis(propionic acid N-hydroxysuccinimide ester). We anticipated that this long chain compound can arrange more regularly on the gold surface, however, the synthesis of these compounds have not been achieved yet, and new synthetic strategy is needed.