金屬超分子.
腙基架橋萘啶之銀錯合物研究

超分子結構的獲得，配位子的設計是重要的一步，而本篇研究目標定位於金屬簇螺旋( Cluster Helicate ) 超分子結構。要形成簇狀螺旋錯合物，配位子必須要能鍵結多個金屬離子，基於此，我們設計配位子是含有三個萘啶結構，並由柔軟且具配位能力的腙基連接組成。金屬離子則選用銀離子，因為銀離子的鍵結構形可調性高，可依不同類型配位子所提供的鍵結單元調整其鍵結形狀，且銀離子為過渡金屬，具有d 軌域含有未成對電子，使金屬簇螺旋超分子結構會產生豐富的物理及化學性質，在奈米系統上，更可以形成金屬線的特異表現。因此，設計可以鍵結多金屬離子的系統，使其形成有系統的金屬簇超分子錯合物。在本篇報告中合成了一個具腙基架橋的萘啶配位子，並與銀離子形成錯合物，利用1-D NMR、COSY、HMBC、HSQC等方法，成功的鑑定出配位子以及錯合物的結構。在UV-Vis吸收光譜中發現配位子與錯合物的π→π*有明顯位移，螢光波長在510 nm。且從UV-vis滴定光譜中，得到錯合物的自組裝過程為[L]、[ML]、[M2L]、[M3L]、[M3L2]、[M4L2]、[M5L2]、[M6L2]，並在ESI-MS質譜儀中確認[M6L2]的存在。此外利用電子吸收光譜酸鹼滴定，求得萘啶配位子之pKa為3.83。

關鍵字

金屬超分子；萘啶化合物；銀錯合物

並列摘要

Metallosupramolecules have been extensively studied due to their supramolecular behavior with properties supplemented by the metal ions, such as electronics, magnetism, color, or electrochemical behavior. Moreover, metalloupramolecules have been utilized to fabricate metal nanomaterials and molecular machine because of their ability to self-assemble into ordered suprastructures. A novel polydentate ligand L was synthesized by condensation of 2,7-dihydrazinyl-1,8-naphthyridine and 2-dimethylglyoxal-hydrazonyl- naphthyridine. Reaction of L ligand strands with silver perchlorate in CH3CN generates a double helical hexanuclear complex. The ligands and silver complex were successfully identified by 1H-NMR and 2-D NMR technical as COSY, HMBC and HSQC. The complexation behavior of L was studied by UV-Vis spectrophotometric titration. The experimental results reveal the formation of hexanuclear complexes [Ag6L2]+6. Moreover, the double-helical structure of [Ag6L2]+6 was confirmed by electrospray ionization mass spectrometer. The pKa value of ligand L was determined by UV-Vis spectroscopic titration.

並列關鍵字

Supramolecule ； Silver complex ； Self-assembly ； Helicate ； Hydrazone bridged

參考文獻

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金屬超分子. 腙基架橋萘啶之銀錯合物研究

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