| 摘要: | 由於放光材料於分子辨識、螢光探針、顯微鏡成相、有機發光二極體 (OLED)等現代科技中被廣泛應用，故放光範圍寬廣之發光材料於近期吸引 科學家們的研究與討論。液晶材料具有良好的自組裝特性，其誘導分子間 無缺陷排列的能力與高電荷遷移率皆可進而提升裝置之效能。開發同時具 有液晶與發光特性之材料則是目前的一大挑戰。
本研究延伸實驗室先前所研究之結構，保留分子同時含有五員雜環與 β-diketonate 之設計，以及含有相異雙五員雜環之設計，將化合物 1a-b、 3a-c 其中一側之苯環置換成?環，製備化合物 2a-b、4a-c，藉此延長分子 內的共軛系統、增加分子結構之不對稱性及分子間作用力，並藉由偏光顯 微鏡、微差式掃描熱分析儀與 X-ray 繞射之鑑定得知，含有?環之化合物 2a-b、4a-c 成功誘導出較寬廣之液晶相範圍。此外，將化合物 1a-b、2a-b 與二氟化硼進行配位，藉由硼原子缺乏 p 軌域電子的特性，延長其錯合物 分子內之共軛並降低分子的 LUMO 軌域，成功開發放光紅移、較大 stokes shift 之化合物 1a-BF2、1b-BF2、2a-BF2、2b-BF2。本研究亦將化合物 1a- b、2a-b 與 Cu 進行配位，引入重原子效應，希望開發高量子產率之磷光液 晶材料，此系列化合物 1a-Cu、1b-Cu、2a-Cu、2b-Cu 雖具有液晶性質， 但不具有良好之熱穩定性，其熱裂解溫度低於成清點溫度，故未進行光物 理性質之測試。;In recent years, emission materials are especially interesting because the wide range of applications in advanced technologies such as molecular recognition, fluorescence probes, microscopy imaging, and organic light-emitting diodes (OLEDs). Liquid crystals are also interest in research, because its properties of orientational ordering and molecular self-organization. These materials provided charge carrier mobility to improve device performance. Therefore, exploiting the luminesecent mesogens actract lots of discussion.
In this work, five-membered heterocyclic ring derivatives 2a-b, 4a-c and their borondifluoride complexes 1a-BF2, 1b-BF2, 2a-BF2, 2b-BF2 and coper complexes 1a-Cu, 1b-Cu, 2a-Cu, 2b-Cu were prepared and investigated. All compounds were characterized by 1H and 13C NMR spectroscopes, elementary analysis. Their mesomorphic behavior was studied by polarized optical microscope, differential scanning calorimeter and X-ray diffraction. All compounds exhibited liquid crystal phases except borondifluoride complexes. Futhermore, compounds 2a-b, 4a-c with five-membered heterocyclic ring and naphthalene have wider mesophases, owing to the increasing of structure asymmetry and intermoluce interaction. Optical property was investigated by UV/Vis and photoluminescence spectroscopy. Because of the donor-acceptor effect, their BF2 complexes have emissions of near-infrared wavelengths. |
