Fluorinated organic molecules are important for their role in pharmaceuticals, agrochemicals, materials and medicine. In this thesis we have studied reaction of fluorodehydroxylation with the imidazole-type reagent (2-chloro-1,3-bis(2,6-diisopropylphenyl)-1H-imidazol-3-ium dihydrogen trifluoride), which has the advantage of being stable under ambient conditions and reactive in the presence of water, while it can be regenerated using aqueous solution of hydrogen fluoride. The deoxyfluorination was studied on model substrates of differently substituted benzyl alcohols. The focus was on time, temperature, solvent, type of base, and the ratio of substrate, reagent and base. For the main model substrate 4-tert-butylbenzyl alcohol, 76% conversion to 4-tert-butylbenzyl fluoride was achieved by varying the conditions. The reaction pathway was also investigated and 4-tert-butylbenzyl chloride was identified as an intermediate product of the two-step deoxyfluorination mechanism. The Hammett equation was used to determine the reaction constant ρ and the SN2 mechanism of the nucleophilic substitution was derived. Some other substituted benzylic alcohols were converted to the corresponding fluorides with the reagent, and the activity of the reagent was also demonstrated on some other types of substrates (carboxylic acid, aliphatic alcohols).
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