Diastereoselective Synthesis of Substituted Chromenopyrrolidinones from Amino Acid-Derived Nitriles

Novel, substituted chromenopyrrolidininones have been synthesized from natural amino acid derivatives through an unprecedented sequence involving a Knoevenagel-Transesterification sequence and an allylative palladium-catalyzed cyclization reaction. The products are nature-inspired heterocycles derived from natural amino acids. The targets could be synthesized with varying degrees of stereoselectivity: racemization is a known issue with amino acids and provided a formidable challenge to our method development, as well. Altogether, six derivatives were synthesized with yields from moderate to good.