碳-氫鍵活化合成錸金屬環錯合物及其分子辨識研究

Abstract

本論文的研究是利用Re2(CO)10與2-(2-pyridyl)-benzimidazole (HBim-C6H4N) 及1,4-bis(benzimidazole-1-ylmethyl)-2,3,5,6-tetramethylbenzene (p-TXyBim, L1)、 α,α′-bis(benzimidazol-1-yl)-o-xylene (o-XyBim, L2) 、 1,3-bis(benzimidazole-1-ylmethyl)-2,4,6-trismethylbenzene (m-TXyBim, L3) 、 1,2-bis(4-pyridyl)ethane (bpea, L4)或1,3-bis(4-pyridyl)propane (bppa, L5)等有機配 子在水熱條件下自組裝合成，分別得到[{Re(CO)3(μ-Bim-C6H4N)}2(μ-L1)] (1)、 [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L2)] (2)、[{Re(CO)3}2(μ-Bim-C6H3N)(μ-L3)] (3)、 [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L4)] (4)、[{Re(CO)3}2(μ-Bim-C6H3N)(μ-L5)] (5)等錸 金屬錯合物。錯合物15經由UV-vis、IR、NMR、FAB-MS等方法鑑定，其結構 也以單晶X光繞射法解析。化合物1為一雙核非環狀錯合物，具發光特性，可藉 由可見-紫外光光譜上的差異來辨識Hg+、Cu2+及Ag+等三種金屬離子。化合物25 的結構為雙核金屬環化物，除了其光物理性質之外，該系列分子的特色是錸金屬 將有機配子2-(2-pyridyl)benzimidazole中3號位置(C3)的碳-氫鍵活化而形成雙核 環化物。Compounds [{Re(CO)3(μ-Bim-C6H4N)}2(μ-L1)] (1), [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L2)] (2), [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L3)] (3), [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L4)] (4), and [{Re(CO)3}2(μ-Bim-C6H3N)(μ-L5)] (5) were successfully synthesized by treatment of Re2(CO)10 with 2-(2-pyridyl)-benzimidazole (HBim-C6H4N) and 1,4-bis(benzimidazole-1-ylmethyl)-2,3,5,6-tetramethylbenzene (p-TXyBim, L1), α,α′-bis(benzimidazol-1-yl)-o-xylene (o-XyBim, L2), 1,3-bis(benzimidazole-1-ylmethyl)-2,4,6-trismethylbenzene (m-TXyBim, L3), 1,2-bis(4-pyridyl)ethane (bpea, L4), or 1,3-bis(4-pyridyl)propane (bppa, L5) respectively, under solvothermal conditions. The series of rhenium-based complexes 15 was characterized using IR, UV-vis, and NMR spectroscopic techniques. The structures were further confirmed by X-ray single-crystal diffraction analysis. Compound 1 is a dimetallic complex with an acyclic conformation. Compound 1 exhibited luminescent properties. In addition, it recognized Hg+,Cu2+ and Ag+ ions by means of discrimination on UV-vis spectra. Crystal structures showed that compounds 25 possess dimetallic cyclic conformations. It is noteworthy that C-H activation on 2-(2-pyridyl)benzimidazole occurred during preparation of these metallacyclic compounds.