本篇論文以一系列缺電子性錸金屬三羰基錯合物為主要的陰離子感測器，以錸金屬為主要配位中心，配位的缺電子結構為萘四羧酸二醯亞胺(NDI)，此結構具有較大的正四極矩，是探索陰離子⁃π相互作用的理想π酸性芳香環系統。利用合成結構改變兩錸金屬間距離，間接影響到兩NDI間的距離，透過類似的單晶結構，可大致推算錯合物BppEb-Re-L2與錯合物Bppb-Re-L2兩NDI間的距離分別為9.108 Å與8.798 Å，另外再設計單核錸金屬的錯合物BrRe(CO)3(L2)2與雙核錸金屬的錯合物BppEb-Re-L2與錯合物Bppb-Re-L2做比較。 由陰離子辨識實驗可知，錯合物BrRe(CO)3(L2)2與錯合物BppEb-Re-L2對於F–與CN–兩陰離子作用的機制不太一樣。電化學還原吸收光譜與電子順磁共振譜中因形成易於辨識的自由基陰離子可推斷加入CN–的途徑可能是透過電子轉移的方式。而1H NMR、19F NMR與質譜的測試中可確認缺電子的NDI片段與F–、CN–之間有陰離子-π作用力，從19F NMR與吸收光譜的測試中可得知F–滴定的過程中並沒有產生F˙的自由基陰離子，可推斷加入F–的途徑不是透過電子轉移的方式，而有可能是電荷轉移的方式。 另外，單獨測試配體L2 的陰離子辨識實驗，發現在陰離子的感測實驗中錯合物BrRe(CO)3(L2)2和配體L2 的性質比較相似，由陰離子滴定數據中可知錯合物BppEb-Re-L2在陰離子感測的方面具有較高的敏感度，可推測兩NDI間的距離會影響陰離子的感測程度。由此可推測兩NDI間的距離比錯合物BppEb-Re-L2近的錯合物Bppb-Re-L2會成為更有效的陰離子辨識感測器，透過電子轉移與電荷轉移導致的顏色變化，可簡單的用肉眼辨識F–與CN–。 ;Here, we synthesized a series of Electron-Deficient Re(I) Tricarbonyl Complexes for anion recognition. Rhenium is the main coordination center in our compounds. The electron-deficient part is naphthalene diimides(NDI), which has a large positive quadrupole moment and is a well-known π-acidic aromatic ring for understanding the mechanisms of anion−π interactions. We designed and synthesized BppEb-Re-L2 (n = 2) and Bppb-Re-L2 (n = 1) with the different distances between the two NDI ligands, which are 9.108 Å and 8.798 Å. Furthermore, we designed and synthesized single rhenium complex BrRe(CO)3(L2)2 to make a comparison. From anion sensing experiments, we could see there were two mechanisms when we added F–、CN– to BrRe(CO)3(L2)2、BppEb-Re-L2 solution. We conducted spectroelectrochemical analysis and EPR analysis of BrRe(CO)3(L2)2 and BppEb-Re-L2, and we could predict that there might have electron transfer from CN– to NDI due to the formation of NDI˙– and NDI2– which was observed in the UV-Vis absorption spectra too. From 1H NMR、19F NMR and Mass spectra, we could see the anion-π interactions between F–、CN– and complexes. The 19F NMR spectrum didn’t show any oxidation of F– to F˙, which indicated no electron transfer happened. Maybe it underwent charge transfer process. Furthermore, we conducted several anion sensing experiments for L2 ligand. And we discovered that the sensing properties between L2 ligand and BrRe(CO)3(L2)2 were similar. But BppEb-Re-L2 is more sensitive to anion recognition than L2 ligand and BrRe(CO)3(L2)2. To sum up, we could point out that the distance between two NDI ligands will make a great influence on anion recognition. We can infer from above results that Bppb-Re-L2 might be the most sensitive anion sensor. And we can recognize F–、CN– easily with our anion sensors due to obvious color change.
