Syntheses and Characterizations of Copper(I), Ag(I) and Ru Complexes with α-diimine ligands

• Main Authors: Chien-Ho Lin, 林建合
• Other Authors: 王文竹
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/20699864254295952027

碩士 === 淡江大學 === 化學學系碩士班 === 93 === The use of the diimine moiety as a part of ligand systems has gained considerable attention in recent years. This is mainly because of the fact that these ligands have the good characteristics of conjugat π electronic system and lowπ* orbital. Further, the investigations on the chemical and physical behavior of ruthenium(II) complexes with the polydendate chelating ligands have attracted much attention. As a consequence of their unique combination of ground- and excited-state properties, this class of coordination complexes has played an important role in the devolpment of chemistry, such as photochemistry, photophysical, photocatalysis, electrochemistry, chemiluminescence, electrochemiluminescence, and supramolecular photochemistry. The main purpose of this study is to synthesze and characterize a series of novel diimine ligands, and their Ru(II), Ag(I) and Cu(I) complexes, [Ru(L)(bpy)2](PF6)2, [Ag(L)(PPh3)2] (ClO4), [Cu(L)(PPh3)I] and [Ag(L)]n(ClO4)n . The absorption spectra of the Ru(II) series complexes show intense ligand-centered(LC) bands in the UV region and broad metal-to-ligand charge-transfer(MLCT) bands at lower bands, about 445nm. All the Ru(II) complexes exhibit intense photoluminescence, which has been attributed to MLCT triplet emission. The maximum emission wavelengths at room temperature in the range of 600 ~660 nm. The cyclic voltammetry was measured, showing a metal-centered RuII / RuIII oxidation with potentials at 1.345 V, as well as two reversible reduction waves with potentials at -1.235 V and -2.16 V, attributed to bpy / bpy- and L / L- respectively. According to the result above, presuming the lowestπ* orbital is occupied by bpy . In the series complexes of Cu(I), the The absorption spectra show MLCT bands ranging from 350 nm to 545 nm, and the maximum emission wavelengths at room temperature in the range of 600 ~640 nm. The cyclic voltammetry show the CuI / CuII oxidation and CuI / Cu0 reduction with the potentials at 0.685 V and –0.545 V respectively. The electrochemistry behavior correspond with the typical Cu(I) property of the literature . In the complexes of [Ag(L)(PPh3)2] ](ClO4) and [Ag(L)]n(ClO4)n, all the photophysical properties are similar to their ligands’ . The complex, [Ag(L)]n(ClO4)n is prepared in a 1:1 ligand-to-metal molar ratio and structurally characterized by single-crystal X-ray analysis, showing one-dimensional coordination polymers. The Ag(I) centers exhibit a distorted tetrahedral configuration, there are not obvious interactions with the adjacent Ag(I) units, but exist weak π•••π stacking interactions in the crystal packing. The coordination polymers are characterized as zipper structure .