Syntheses And Crystal Structures Of Triazole Derivative Ligands And Their Complexes

The complexes of transition-metal ions with triazole derivatives have gained considerable attention in recent years. Because some of them exhibit spin crossover behavior, it can be used potentially to molecular electronic devices. Three ligands 3-phenyl-6-(pyridine-4-yl)-1,2,4-triazolo[3,4-b]1,3,4-thiadiazole(L¹), 3-phenyl-6-(pyr idine-3-yl)-1,2,4-triazolo[3,4-b]1,3,4-thiadiazole(L²) and 3,6-diphenyl-1,2,4-tri-azolo [3,4-b]1,3,4-thiadiazole(L³) have been synthesized. And two complexes of CuII with L¹ have been synthesized and characterized. Moreover a complex of AgI and two complexes of CuII with 5-methyl-1-(4-methylphenyl)-1,2,3-triazole-4-carboxylic acid (L⁴) have been synthesized and characterized. Their crystal structures were determined by X-ray analyses. A new ligand N-(benzothiazole-2-yl)-2- (5-pyridin-4-yl)-1,3,4-thiadiazol-2-mercapto)acetamide has been synthesized, its structure has been determined by X-ray. The thesis is composed of the following four section:Part I. L^1L3 were synthesized by several-step reactions from benzoic acid ethyl ester, the structures of L^1L3 were confirmed by elemental analysis and IR spectra.Part II. The complexes of [Cu(L¹)₂(NO₃)₂(CH₂Cl₂)]_∞(1) and [Cu₂(L¹)₄(OH)₂(Me OH)₄·BF₄]_∞(2) have been prepared by reaction CuII with L1, and the structures of 1 and 2 were determined by X-ray analyses.Part III. The complexes of [Cu(L⁴)₂(MeOH)] (3), [Ag₂L₂⁴(HL⁴)₂(MeOH)] (4) and [Cu(L⁴)₂(H₂O)₂]·2H₂O (5) have been prepared, and the structures were determined by X-ray analyses.Part IV. A new ligand N-(benzothiazole-2-yl)-2- (5-pyridin-4-yl)-1,3,4-thiadiazol-2-mercapto)acetamide(L⁵) has been synthesized, and its crystal structure has been analysis by X-ray diffraction.