In recent decades, the use of N-heterocyclic carbenes (NHC) as ligands has been greatly expanded, paricularly in transition metal complexes for homogeneous catalysis. The discovery of NHC ligands had a major impact on the development of the chemistry of transition metal complexes, especially for copper, nickel and cobalt. The initially exotic complexes soon gained great practical importance due to their relatively simple and efficient preparation, the easy handling of the imidazolium salt precursor and their ability to stabilize reactive transition metal intermediates.
In the Master thesis, we optimized the reaction pathway to the imidazolium NHC ligand (IPr**) 1,3-Bis[2,6-bis[bis(4-tert-butylphenyl)methyl]-4-methylphenyl]-1H-imidazol-3-ium chloride and in the next step to the copper(I) chlorine complex with this ligand [(IPr**)CuCl]. The progress of the reactions and the isolated products were monitored by spectroscopic methods. Intermediates and products were characterized by 1H and 13C NMR, IR and mass spectroscopy. Furthermore, we tried to replace the chloride ligand in the copper(I) complex with some other ligands such as –OH, –NO3 and –OCOOH.
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