Catalyst design for asymmetric organozinc addition to aldehydes and progress toward the total synthesis of the marine alkaloid, (-)-lepadiformine

A novel dihydropyridone was synthesized in search for a chiral ligand for the asymmetric addition of an alkyl group to an aldehyde. The target amine was derived from an enamine through a hydrogenation reaction.; A study directed toward the total synthesis of the marine alkaloid (-)-lepadiformine was carried out. Two approaches were investigated toward the core perhydroquinoline system. The first approach utilized a Grignard addition to an N -acylpyridinium salt and a [2+2] photochemical addition as the key synthetic steps. The second approach was based upon quinoline chemistry. The model study was completed with a one-carbon alkene homologation to form a terminal butane. An asymmetric route was examined.