The goal of this master thesis was the synthesis of selected triazolium salts, that would be functionalized with two pyridyl substituents, as potential ligands for complexes of palladium and other transition metals. We have successfully synthesized two such triazolium salts. The framework of both is 1,4-di(pyridine-2-yl)-1H-1,2,3-triazolium salt, which in one case is methylated at position 3, and arylated in other. The literature pathway for methylated compound uses 1,4-di(pyridine-2-yl)-1H-1,2,3-triazole as starting precursor that is methylated, however, majority of methylation occurs on pyridine (75%), and only 25% of the desired product is formed. We synthesized the starting 1,4-di(pyridine-2-yl)-1H-1,2,3-triazole with ‘click’ reaction between 2-azydopyridine and 2-ethynilpyridine. We tested three different copper catalysts for this transformation and optimized the reaction conditions. We wanted to synthesize the final product from 1,4-di(pyridine-2-yl)-1H-1,2,3-triazole with a synthetic pathway that includes the protection of pyridine with oxidation, methylation and deprotection of the N-oxide. We have managed to obtain the desired ligand, but with low overall yield (32%). We attempted the synthesis of the palladium complex with methylated triazolium salt. We have managed to obtain encouraging results with mass spectrometry, which indicated desired palladium complex formation with two bonded ligands, but the NMR spectra of the same products were too complex to definitely describe the structure of the complex. We have tried to obtain suitable crystals for diffraction analysis, but were unsuccessful. Arylated triazolium salt was prepared from 1-phenyl-5-(pyridine-2-yl)-1H-1,2,3-triazole, which we synthesized with ‘click’ reaction, and arylated subsequently. We have successfully synthesized the arylated triazolium salt, which we then tried to coordinate to palladium. We again obtained encouraging mass spectroscopy results, which indicated desired palladium complex formation with two bonded ligands, but although we tried several solvents and anion exchange, we did not manage to obtain crystal structure or NMR spectra from which we could inconclusively determine the structure of the complex.
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