以三苯胺爲主的有機配子之金屬配位聚合物的電化學研究和性質探討

Abstract

摘要 本論文採用烏耳曼耦合反應（Ullmann coupling）合成以三苯胺為主的有機配子-tris(4-(1H-1,2,4-triazol-1-yl)phenyl)amine (TTPA)。TTPA有機配子具有電化學活性，藉由引入三苯胺和金屬離子可合成具可調控電化學性質的材料。在第三章，本論文將有機配子分別與金屬鹽類錳離子以及鈷離子進行反應，合成具有二維結構之有機金屬配位聚合物 [Mn(TTPA)Cl2·DMF]n (1) 和 {[Cu(TTPA)Cl2]·2DMF}n (2)。兩個化合物皆利用單晶X-ray繞射結果探討其晶體結構，並以固態電化學，氧化劑和電化學光譜探討化合物之物理性質。 本論文利用TTPA與具有不同羧酸根之有機配子與金屬鹽類配位聚合，可合成具有三維結構之有機金屬配位聚合物3-6。金屬錯合物不但保有TTPA有機配子之電化學活性，還更因結構不同，而具有不同性質。化合物{[Zn3(TTPA)2(DHTP)3]·2DMF}n (3) 結構穩定具有孔洞，對二氧化碳的捕捉表現優異。化合物3最特別的是，藉由氧化還原之電化學反應進一步調控固體螢光的開關。化合物 {[Co2(µ-OH2)(TTPA)(DTDN)2·DMF]·H2O}n (4) 因為採用了鈷金屬離子，導致其結構雙鈷配位而擁有磁性特徵。化合物{[Co(TTPA)(TDC)(H2O)]·2DMF}n (5) 和 {[Cd(TTPA)(TDC)]·2H2O}n (6) 分別利用鈷和鎘離子，在相同的反應溫度和溶劑環境下得到兩次互穿和四次互穿之結構。

It is possible to alter the properties of redox-active materials by altering their redox state. The incorporation of a redox-active ligand in the construction of multifunctional materials has received limited attention despite the potentially high versatility. The tris(1,2,4-triazolphenyl)amine (TTPA) ligand with its triarylamine as a core is well-known for its redox and spectral properties. The TTPA ligand has significant potential for the development of coordination polymers where interplay exists between redox, optical, and host–guest properties. This thesis investigates the synthesis, design and physical properties of coordination polymers with TTPA incorporated within them. Two dimensional coordination polymers can be achieved by merely incorporated the TTPA ligand with Cu2+ and Mn2+ metal ions to afford [MnTTPACl2·DMF]n (1) and {[CuTTPACl2]·2DMF}n (2). The redox-active behaviour of 1 and 2 was interrogated using chemical oxidants, solid state cyclic voltammetry and in situ solid state spectroelectrochemical techniques. Frameworks with higher dimensionality 3–6 can be obtained when the TTPA ligand is inserted with carboxylates as a co-ligand. Besides remained an electroactive framework, additional physical properties were observed and characterised. The robust and permanent porosity of {[Zn3(TTPA)2(DHTP)3]·2DMF}n (3), (DHTP = dihydroxyl terepthalic acid) is confirmed by gas adsorption measurements. Compound 3 has a Brunauer-Emmett-Teller (BET) surface area of 715.76 m2/g. 3 shows favorable interaction with carbon dioxide. One highlight of 3 is its photoluminescence intensity could be tuned “on” and “off”. {[Co2(µ-OH2)(TTPA)(DTDN)2·DMF]·H2O}n (4), (DTDN = dithiodinicotinic acid) constructed using Co2+ as the metal precursor, the binuclear centre of the framework allows for magnetic measurement. Magnetic studies indicated that 4 exhibits antiferromagnetic interactions and undergoes a field-induced spin-flop transition. {[Co(TTPA)(TDC)(H2O)]·2DMF}n (5), (TDC = thiophene dicarboxylate) and {[Cd(TTPA)(TDC)]·2H2O}n (6) were synthesised under same reaction conditions except for the use of different metal ions. The degree of interpenetration could be controlled by the metal ions as the sole reaction variable, and it subsequently influenced the coordination behaviour of TDC2– (thiophene dicarboxylate) ligand. Therefore 5 is 2-fold interpenetrated, and 6 is 4-fold interpenetrated. Spectral, fluorescence and host-guest properties of the frameworks were able to tune as a function of the redox state. In situ UV/Vis/NIR, fluorescence spectroelectrochemical techniques in both the solution and solid-states formed an integral part of the characterization of these compounds. The thesis describes a systematic approach towards the study of the fundamental and applied aspects of redox activity as a platform for multifunctional systems. The functionalities can be controlled and fine-tuned.