中文摘要 本論文為利用鈀金屬催化方法合成一系列含N,N-雙吡啶之三芳基胺並探討其對金屬離子螢光化學感應之行為，藉由X-光晶體繞射結構對其螢光變化機制作一深入的研究。 我們利用鈀金屬催化的C-N偶合反應成功地合成了新型二苯乙烯胺系列的本質型螢光離子感應器，因為N-吡啶(胺基共軛效應)取代使得此系列化合物擁有高螢光量子產率，來作為螢光訊號的改變，且N,N-二吡啶為一良好的過渡金屬離子的接受區；結果顯示，此系列化合物與鋅離子錯合後，原來分子內電荷轉移(ICT)的放射峰逐漸減弱取而代之是藍位移微弱Le (local excited)峰生成；而鹼金與鹼土族隨著離子的增加對吸收與放射光譜則無影響。由螢光光譜及X-光繞射晶體數據得知，N,N-雙吡啶與鋅離子錯合後，C(吡啶)-N-C(吡啶)構成的平面與二苯乙烯胺的苯環平面之夾角變大，因而抑制了ICT。由於雙吡啶胺基與二苯乙烯部分的共軛性減弱，這是導致螢光光譜變化的因素。 此外，我們亦合含N,N-雙吡啶之三芳基胺系列來探討夾角大小與光譜變化之間的關係。由螢光放射光譜與X-光繞射晶體數據亦顯示，放射峰偏移且強度增加的程度，和C(吡啶)-N-C(吡啶)構成的平面與苯環平面的夾角大小有極大的關係。 Abstract In this thesis, we report the synthesis of a series of triarylamines containing the N,N-dipyridyl group via palladium-catalyzed C-N bond formation. The fluorescence sensing behavior of these triarylamines to metal ions was also investigated with a particular focus on the relationship between the X-ray crystal structures and the corresponding fluorescence responses. We have successfully prepared new aminostilbene-based palladium-catalyzed by utilizing the Pd-catalyzed C-N coupling method. The probe design was based in part on the fact that the N,N-dipyridyl group is a good receptor for transition metal ions. As a result of the “amino conjugation effect”, N-aryl substituted 4-aminostilbenes are strongly fluorescent, which is an attribute in performing the “on-ff” type of fluorescence signaling. We observed that the emission from the internal charge-transfer (ICT) state is decreased but a week and blue-shifted emission, which is designated as a locally excited (LE) emission, is formed when the fluoroionophores are complexed with zinc(II) ions. In contrast, alkali and alkaline earth metal ions impose little or no effects on the absorption and emission spectra. On the basis of the fluorescence spectra and the X-ray crystal structures, we attribute the decrease of ICT emission to the de-conjugation of the system by twisting the stilbene-dipyridylamino (C-N) bond when the complexation occurs. We also synthesized a series of simple triarylamines to further investigate the relationship between the C-N bond twisting and thobserved spectra changes. Our results suggest that the C-N bond twisting play an important role in the fluorescence responses of these N,N-dipyridyl-containing triarylamines.
