"1,8號位雙取代之萘衍生物之合成、性質探討"

Abstract

本篇論文是以萘環為結構中心，選擇在具有立體障礙的1,8位置(Peri)分別接上一個咔唑基團以及不同拉電子基團(噁二唑、苯并咪唑、丁腈、硝基、甲酸基)，合成一系列可藉由立體障礙阻斷共軛的雙偶極咔唑化合物。由於推拉電子基團之間的距離十分接近，所以針對不同拉電子基的化合物進行光物理及電化學性質的測量與比較，並觀察基團間可能的交互作用。另外，將咔唑基團置換成具有重原子效應的溴原子，對這些不同拉電子基的萘溴衍生物進行光物理及電化學性質的比較與探討。 經由螢光、磷光光譜以及循環伏安法的測量結果，得知所有萘化合物的最低未填滿分子軌域(LUMO)及三重激發態都是位在萘環結構上，而且三重激發態的能階並不會隨著取代基改變而有太大的變化，其中雙偶極萘化合物皆在2.55 eV附近，以化合物12為代表與綠光磷光有機發光二極體(PhOLED)之客發光體Ir(ppy)3以及紅光磷光有機發光二極體之客發光體Ir(2-phq)2(acac)進行能量轉移實驗，得知其對於Ir(ppy)3與Ir(2-phq)2(acac)良好的能量轉移效率，未來也許有作為綠光及紅光有機發光二極體主發光體材料的潛力。

In this study, a series of bipolar compounds that containing carbazole group at the 8-position of naphthalene, and with the 1-position substituted by an electron-withdrawing group (oxadiazole, benzimidazole, nitrile, and nitro, formic acid) were synthesized. The 1,8-position di-substituted naphthalene, being called as peri-substituted of naphthalene derivatives, has large steric hindrance resulting an orthogonal arrangement that interrupted the conjugation between the donating and the withdrawing groups. The 8-position substituted carbazole of naphthalene derivatives were discussed that intermolecular interaction between carbazole and withdrawing moieties and through measuring photophysical and electrochemical properties. Furthermore, we replaced carbazole group with bromine which has heavy atom effect, and demonstrated the properties of these naphthalene derivatives with different withdrawing moieties through measuring photophysical and electrochemical properties. Fluorescence, phosphorescence spectra and cyclic voltammetry were used to characterize the 1, 8-position di-substituted of naphthalene. The LUMO and the triplet state of all naphthalene derivatives are located in naphthalene structure. The triplet energy doesn’t change a lot with different substituent. The triplet energy of bipolar naphthalene derivatives are about 2.55 eV, and we found that compound 12 can transfer energy to the Ir(ppy)3 and the Ir(2-phq)2(acac) efficiently, so it is possible that these bipolar naphthalene derivatives become a good host material of green and red PhOLED.