Blue-phosphorescent bis-cyclometalated iridium complexes with aryl isocyanide ancillary ligands
Blue-phosphorescent bis-cyclometalated iridium complexes with aryl isocyanide ancillary ligands
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DOI：
10.1016/j.poly.2019.114332
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发表时间：
2020-03-01
期刊：
影响因子：
2.6
通讯作者：
Teets, Thomas S.
中科院分区：
文献类型：
--
作者：
Canada, Louise M.;Kolling, Johanna;Teets, Thomas S.
高效蓝色磷光有机金属络合物的设计一直是光电子学领域的一大挑战。本文报道了一系列通式为[Ir((CY)-Y-Boolean and)(2)(CNAr)(2)](PF6)的阳离子、异氰化物连接的双环金属化Ir络合物[Ir((CY)-Y-Boolean and)(2)(CNAr)(2)](PF6)，其中(CY)-Y-Boolean是基于三唑的(CN)-N-Boolean和环金属配体或基于NHC的(CC)-C-Boolean和：环金属配体，CNAr是芳基异氰化物。三氮唑和NHC衍生的环金属配体与p-酸性异氰酸酯辅助配体结合，产生较大的HOMO-LUMO能隙，并在光谱的蓝色区域产生光致发光。这些化合物是通过一般的合成程序合成的，并以中等到良好的分离产率进行分离，结合核磁共振光谱、质谱学和X射线结晶学(对于八种化合物中的六种)来确定每种化合物的特性和总体纯度。用循环伏安法研究了化合物的氧化还原性质，证明了较大的HOMO-LUMO能隙是蓝色光致发光的关键。这些三氮唑基化合物在室温下在液体溶液中都有微弱的发光，所有的配合物在77K下都能在冷冻溶剂玻璃中或在室温下固定在透明的聚甲基丙烯酸甲酯(PMMA)薄膜中发光。光致发光光谱的Cie坐标表示所有化合物的纯蓝色发射，CIEy
The design of organometallic complexes with efficient blue phosphorescence remains a challenge in the field of optoelectronics. This paper describes a series of eight cationic, isocyanide-ligated bis-cyclometalated iridium complexes of the general formula [Ir((CY)-Y-boolean AND)(2)(CNAr)(2)](PF6), where (CY)-Y-boolean AND is a triazole-based (CN)-N-boolean AND cyclometalating ligand or an NHC-based (CC)-C-boolean AND: cyclometalating ligand, and CNAr is an aryl isocyanide. The triazole- and NHC-derived cyclometalating ligands, in combination with the p-acidic isocyanide ancillary ligands, result in large HOMO-LUMO gaps and engender these compounds with photoluminescence in the blue region of the spectrum. The complexes are synthesized by a general synthetic procedure and isolated in moderate to good isolated yields, with a combination of NMR spectroscopy, mass spectrometry, and X-ray crystallography (for six of the eight compounds) establishing the identity and bulk purity of each compound. The redox properties of the compounds are studied by cyclic voltammetry, which provide evidence for the large HOMO-LUMO gaps that are critical for the blue photoluminescence. The triazole-based compounds are weakly luminescent in fluid solution at room temperature, and all complexes luminesce at 77 K in frozen solvent glass or at room temperature when immobilized in a transparent poly (methyl methacrylate) (PMMA) film. CIE coordinates for the photoluminescence spectra indicate pure blue emission for all compounds, with CIEy