三吡啶二胺配基(H2tpda)之四核鉬與釕金屬串及新型三核鎳金屬串的合成與研究

Abstract

The aim of thesis can be separated in two parts. The first part of thesis is to investigate the tri-nickel metal string complexes which are surrounded by the new type of asymmetric tri-nitrogen ligand, Hphpta (5-phenylpyridinyl-thiazolylamine). The linear tri-nickel complexes, [Ni3(phpta)4(X)2] (X = Cl, NCS),can be synthesized at high temperature by using naphthalene as the solvent. We can find that the tri-metal string complexes are helically wrapped by four phpta- ligands. The X-ray structure shows that [Ni3(phpta)4Cl2] has some trouble of ligand disorder which means that we cannot distinguish between pyridyl and thiazyl parts of phpta-, owing to their similar structure. Luckily, [Ni3(phpta)4(NCS)2] do not face the problem, and we can find that all the thiazyl part of phpta- ligands bind on the same side of the metal string, known as (4,0)-form. There is no metal-metal bond between any two nickels, by qualitative M.O. analysis. Magnetic measurement shows μeff = 3.37 B.M. at 350 K. Furthermore, the conductance value of [Ni3(phpta)4(NCS)2] is around 1.2 × 10-3 (Go), measuring by STM-bj. The second part of my thesis is focus on synthesis the first tetra-molybdenum metal string complex, [Mo4(tpda)4](PF6), which using N5 ligand, H2tpda (tri-pyridyl-di-amine). The X-ray structural studies reveal that four molybdenum metals are chelated by four tpda- ligands and arranged in a straight line. Judging from the [PF6]- anion, we can sure that the total charge of four molybdenum is 9+. Magnetic measurement shows a paramagnetic curve and S = 1/2. Moreover, we could also find the [Ru4(tpda)4]+ signal on ESI-MS spectra by using Ru precursor.