Boc-glycine was converted with the help of Meldrum's acid into the corresponding tetramic acid. The goal was to C-alkylate tetramic acid with benzyl bromide in the presence of a base and/or to add trans-β-nitrostyrene via Michael addition using an organocatalyst. Two different organocatalysts were used: an achiral and a chiral one. Firstly, the tetramic acid was alkylated with benzyl bromide. The major isolated product was C- and O-di-alkylated compound, while the desired C-mono-alkylated compound represented only the minor product. The C-mono-alkylated product was further reacted with trans-β-nitrostyrene in the presence of an achiral organocatalyst but no reaction occurred. Therefore, trans-β-nitrostyrene was first attached to the tetramic acid in the presence of an organocatalysts. Both organocatalysts successfully catalyzed the reaction. Next, the product of the Michael addition was alkylated with benzyl bromide. Exclusively O-alkylation occurred. With the help of HPLC, enantiomeric excess for the final products were determined and all the products were fully characterized.
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