Degree
Doctor of Philosophy (PhD)
Department
Chemistry
Document Type
Dissertation
Abstract
Four Ni(II) complexes have been obtained with the pyridyltriazole ligand, bpt, or the bis(pyridyltriazole) ligand, m-xpt, in chapter 2. This work was carried out as a comparison with the previously established coordination chemistry of copper(II) with bpt and m-xpt. Initially, the reaction between Ni(II) and bpt only produced one mononuclear compound, [Ni(bpt)2(H2O)2](NO3)2 (1). In order to study the formation of Ni-bpt and Ni-m-xpt complexes in solution, mixtures of Ni(NO3)2 and ligand (m-xpt or bpt) were prepared in different ratios and their UV-Vis spectra measured. The analysis and simulation by the computer program ZSQUAD suggested corresponding individual species of [Ni(bpt)n]2+ and [Ni2(m-xpt)n]4+ (n = 1, 2, 3). Meanwhile, two more complexes of [Ni(bpt)3](PF6)2 (2) and [Ni2(bpt)4(N3)2](PF6)2·2C4H10O (3) (C4H10O = Diethyl Ether) were successfully isolated by introducing N3− and PF6− into the reaction mixture. And one dinuclear complex, [Ni2(m-xpt)2(C2O4)](NO3)2 (4), was prepared to support the formulation of [Ni2(m-xpt)2]4+.
Chapter 3 is part of a study of the formation of copper(II) oxalate complexes. Two Cu complexes with oxalate, Cu(bpt)(C2O4)(DMF) (7) and Cu2(bpt)2(NO3)2(DMF)2(C2O4) (8), were prepared through multiple-steps reactions among Cu(NO3)2, bpt and ascorbic acid. The oxalate was a decomposition product of ascorbic acid. A polymer compound, [Cu(bpy)(C2O4)]n (10), was synthesized through mixing Cu2(bpy)2(OH)2(NO3) with dehydroascorbic acid and Dabco (bpy = bipyridine, Dabco = 1,4-diazabicyclo[2.2.2]octane). Another complex, [Cu2(bpy)2(Dabco)(C2O4)]n(PF6)2n (11), was obtained by adding Dabco into solution of [Cu(bpy)2]2+. Dabco functioned as a reducing agent in these reactions and decomposed to oxalate.
Chapter 4 describes the reactions between Pd(CH3CN)4(BF4)2 and m-xpt or p-xpt in mixture solvent of CH2Cl2 and (CH3)2CO. These experiments were assumed to prepare dimer structures similar to copper(II) and nickel(II) complexes. Colorless crystal, [Pd2(m-xpt)2](DMSO)6(BF4)4 (12), was formed. [Pd2(p-xpt)2]4+ was supported by mass spectra.
Chapter 5 describes a side product, Cu(bpy)(C4H4O6) (13), that is formed in a reaction of [Cu(bpy)2(NO3)](NO3), ascorbic acid and Dabco. C4H4O62− is an uncommon product from ascorbic acid degradation. Both inter- and intramolecular hydrogen bonds of O—H···O are found in the crystal structure of (13).
Recommended Citation
Gao, Sen, "Transition Metal Complexes of Pyridyltriazole and Bipyridine Ligands" (2020). LSU Doctoral Dissertations. 5353.
https://repository.lsu.edu/gradschool_dissertations/5353
Committee Chair
Maverick, Andrew
DOI
10.31390/gradschool_dissertations.5353