A Straightforward Approach towards Functionalized Amino Acids and Pipecolinic Acids via Ruthenium-Catalyzed Allylic Alkylation

Chelated amino acid ester enolates react with cis-butene diol substrates via Ru-catalyzed allylic alkylations to functionalized amino acids. The use of [(p-cymene)RuCl₂]₂ as catalyst allows the introduction of Z-configured allylic alcohols in the side chain of the amino acid. They facilitate access to pipecolinic acid and baikiaine derivatives.