This master's thesis describes attempts of optimization of copper-free Sonogashira cross-coupling reaction. Namely, we aimed to accelerate the reaction by accellerating its key step, transmetallation. Two reaction intermediates, the oxidative palladium adduct and the palladium acetylide, were prepared independently. We performed the transmetallation reaction between these two complexes and added different additives to study their influence on the rate of transmetallation. Additives that showed a positive effect were used to accelerate the catalytic reactions between aryl halides and terminal alkynes.
We also investigated the reactivity of various boric acids and terminal alkynes in the palladium-catalyzed coupling reaction with halogenated acetylenes, which led to the desired products.
A terminal alkyne containing a 15N-labeled pyridine ring was synthesized. The latter can enter the Sonogashira coupling reaction as one of the reactants.
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