【作者】 李洪峰；

【导师】 闫鹏飞； 李光明；

【作者基本信息】 黑龙江大学 ， 无机化学， 2012， 博士

【摘要】 稀土β-二酮配合物由于其优良的发光性质已被广泛用于时间分辨荧光免疫分析，生物成像，光纤通讯和有机发光二极管等领域的研究。双β-二酮是两个单β-二酮通过间隔基连接的一类四酮配体。由于其具有多个配位原子及自身酮式与烯醇式的互变异构，使得这类化合物可通过多种配位方式与金属离子配位而形成结构丰富(双螺旋，三螺旋，四螺旋，三角，四面体，笼状，一维链等)的金属配合物。从已有文献来看多核稀土配合物相比于单核稀土配合物具有更高的发光效率，但其高效发光的原因并未被人们所认知。因此，合成一系列双β-二酮稀土配合物并获得其晶体结构，建立结构和发光性质的关系对稀土配合物发光的理论研究具有重要意义。本文通过偶联三种常见双齿β-二酮配体苯甲酰三氟丙酮(BTFA)，二苯甲酰甲烷(DBM)和噻吩甲酰三氟丙酮(TTA)合成了三种四齿双β-二酮配体3,3’-双(4,4,4-三氟-1,3-丁二酮基)联苯(BTB)，3,3’-双(3-苯基-1,3-丙二酮基)联苯(BPB)和5,5’-双(4,4,4-三氟-1,3-丁二酮基)联噻吩(BTT)。通过在芳环适当位置偶联单β-二酮配体实现了对双β-二酮配体结构和激发态能级的可控。芳环间可自由旋转的C-C键使配体与氯化稀土以３:２比例反应时生成了三个系列稀土配合物Ln2L3。X-射线单晶衍射分析证实配合物具有双核三螺旋结构。此外，三个配体中间隔基的改变实现了对配体三线态能级调控，使其与稀土离子的激发态能级达到较好的匹配实现了对不同稀土离子的高效敏化。光致发光研究显示双核配合物相比于单核配合物具有更加优异的发光性能。三个系列配合物的合成、结构的获得及其发光性质的研究为配合物螺旋结构的形成提供了重要了理论指导，为理论上解释双核配合物的发光性能提供了有价值的实验数据。更多还原

【Abstract】 The unique optical properties of lanthanide ions have made their complexes ofintense interest for a wide range of photonic applications such as tunable lasers, lightemitting diodes, optical amplifier, luminescence probes for bio-analysis and medicalimaging. Bis-diketones are derived from the diketones through the bridging spacers,resulting in a series of tetra-ketones, which promise their rich structural chemistry withthe metal ions in various modes. Typical structures are featured by the double-strandedhelical, triple-stranded helical, tetra-stranded helical, triangular, and chainlike motifs.Reviewing the reported literatures, it is found that the fluorescent intensity andefficiency of the multi-nuclear lanthanide complexes are much better than thecorresponding mono-nuclear lanthanide complexes, unfortunately, we do not know toomuch about why. We have designed and synthesized a series of lanthanide complexesassembled about the bis-diketones and their luminescent properties have beeninvestigated, which would pave the way for further study the theoretical work on therelationship of the structures and luminescent behaviors.In this work, we have prepared three bis-diketones BTB, BPB and BTT throughthe coupling of two mono-ketones (BTFA, DBM and TTA) via spacers, respectively.Interestingly, the energy levels of the excited state are controllable through the couplingat the proper position. The rigidity of the aryl groups prevents the two binding sitesfrom chelating a single metal ion, and the flexibility originating from the free rotation ofC-C single bond, allows the formation of structures (Ln: ligand=2:3) in a twistconformation, which has been confirmed by the single crystal structural analysis andMS-TOF. The control on the energy level of triple state of the ligand is achievedthrough introduction of the spacers between the two mono-ketone moieties, whichmatches well with the energy level of the excited state of the lanthanide ions, leading tothe significant sensitization to the lanthanide ions. The fluorescent investigation reveals that dinuclear complexes possess better behavior than the mononuclear complex. Thedesigns, syntheses, and fluorescent studies of the three series of triple-strandedlanthanide complexes have supplied valuable information for the theoretical workconcerning the relationship of the structure and the luminescence.更多还原