Abstract
M.Sc. (Chemistry)
A series of pyrazolyl pyridyl ligands, 2,6-bis{(3,5-dimethyl-1H-pyrazolyl)methyl}pyridine (L1), 2,6-bis{(3,5-di-tert-butyl-1H-pyrazolyl)methyl}pyridine (L2), 2,6-bis{(3,5-diphenyl-1H pyrazolyl)methyl}pyridine (L3), 2-{(3,5-dimethyl-1H-pyrazolyl)methyl)}pyridine (L4), 2-{(3,5-di-tert-butyl-1H-pyrazolyl)methyl}pyridine (L5), 2-{(3,5-diphenyl-1H-pyrazolyl)-methyl)pyridine (L6), 2-{(3-(trifluoromethyl)-5-phenyl-1H-pyrazol-1-yl)methyl}pyridine (L7) were synthesized via a phase transfer catalysed reaction from the appropriate starting materials.
The reaction between L1-L7 and NiCl2(DME) resulted in the formation of the appropriate pyrazolyl ligand nickel(II) chloride complexes indicated as follows: [NiCl2(L1)] (1a), [NiCl2(L2)] (2a), [NiCl2(L3)] (3a), [NiCl2(L4)] (4a), [NiCl2(L5)] (5a), [NiCl2(L6)] (6a), and [NiCl2(L7)] (7a); while the reaction of L1-L7 with NiBr2(DME) resulted in nickel (II) bromide complexes: [NiBr2(L1)] (1b), [NiBr2(L2)] (2b), [NiBr2(L3)] (3b), [NiBr2(L4)] (4b), [NiBr2(L5)] (5b), [NiBr2(L6)] (6b) and [NiBr2(L7)] (7b). These nickel complexes were characterized by elemental analysis, mass spectrometry and Infrared spectroscopy; and in selected cases where single crystals could be grown (i.e. 1b and 7b) by single crystal X-ray crystallography. Complex 1b was identified as a salt with two ligands (L1) coordinated to the nickel and two bromide ions as counter ions...