含咔唑基团芘类荧光材料的合成与发光性质

Synthesis and Fluorescent Properties of Carbazole-based Pyrene Light-emitting Materials

摘要:

以1-溴芘、1,6-二溴芘和9-对乙炔苯基咔唑为原料，通过Sonogashira偶联反应合成了1-（4-（9-咔唑）苯乙炔基）芘和1,6-二（4-（9-咔唑）苯乙炔基）芘两种荧光分子。经熔点、核磁共振氢谱以及元素分析等结构表征，对中间体和目标产物的紫外-可见吸收、荧光发射以及结构与性质之间的构效关系进行了研究。通过结构修饰，可有效调节此类分子的吸收及发射性质。当芘单元作为中心电子受体，以4-苯乙炔基为桥连基，引入咔唑基团作为电子给体时，其分子共轭程度、结构刚性和分子内电荷转移能力显著提高。相对于D-π-A结构的单取代化合物，双取代D-π-A-π-D结构分子的最大发射峰由422 nm红移至446 nm，荧光量子效率由0.64提升至1.08。该类化合物可作为高效的蓝光荧光材料，应用于有机光致/电致发光材料以及有机发光二极管等领域。

Abstract:

Two carbazole-based pyrene compounds, 9-(4-(pyren-1-ylethynyl)phenyl)-9H- carbazole and 1,6-bis((4-(9H-carbazol-9-yl) phenyl)ethynyl)pyrene were synthesized by 1-bromopyrene, 1,6-dibromopyrene and 9-(4-ethynylphenyl)-9H-carbazole via Sonogashira coupling reaction. All proposed structures are characterized by melting point, 1H NMR and elemental analyses. Their optical properties were investigated by UV-vis absorption and emission spectra with the aim of understanding the structure-property correlations. The results indicate that the introduction of carbazole unit as electron donor in the pyrene-based molecule can increase the conjugation, structural rigid and fluorescent quantum yields of the compounds. The optical properties could be tuned by the modification of the structures. These compounds can be utilized as efficient blue fluorescent materials (λemmax = 413 ~ 446 nm, ФF = 0.58 ~ 1.08), which have potential applications in the field of organic lighting-emitting diodes (OLEDS).