Enaminones are compounds consisting of an amino group linked through a double bond to a carbonyl group. They are some of the most frequently employed building blocks in organic, especially heterocyclic synthesis. In my undergraduate thesis, I focused on photochemical oxidation of nitrogen in enaminones. Special attention was given to the selection of appropriate photoredox catalyst. The most logical choice were organic photoredox catalysts, which offer metal-free alternatives to transition metal catalyzed reactions, while also providing appropriate reduction potentials. First attempts of enaminone conversion were done with acridinium photocatalyst. An instant change in color from transparent yellow to dark brown was observed within few minutes, which dramatically decreased reaction yield. Hence, I was trying to prepare an alternative method, which would preserve transparency of solution throughout the duration of the reaction. The best results were obtained while using anthraquinone as catalyst. Optimized reaction method was than tested on different types of enaminones. Best yields were obtained, when 1,2-dichloroethane was employed as a solvent.
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