Organocatalysis, which is beside metal and enzymatic catalysis part of asymmetric synthesis, has become an important area of modern organic synthesis. Representatives of organocatalysts are small organic molecules that lead reactions to stereoselective outcome. Commonly used bifunctional organocatalysts contain thio(urea) or squaramide fragments. Potential catalysts for asymmetric reaction are organocatalsysts with thiosquaramide fragment which are analogues of squaramide organocatalsysts. In the dissertation we were interested in the effect of the organocatalsyst with the thiosquaramide fragment on the stereoselectivity of the reaction between N-methylisatin imine and 3-phenylisoxazol-5(4H)-one. The second conversion step was electrophilic fluorination of the resulting intermediate. Stereoselective outcome of reaction is influenced by different parameters; therefore, we optimized the reaction conditions. We tested the effect of different organocatalysts, solvent and catalyst concentration on the stereoselectivity of the reaction. After determining the optimal reaction conditions, we used them to study organocatalytic transformation between differently substituted isatin imines and 3-phenylisoxazol-5(4H)-on. The final products, with two centers of chirality, are formed in two stages. The isolated products are analyzed with HPLC analysis. The products are evaluated with enantiomeric excess and diastereomeric ratio. The results showed high ee values.
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