Transition metal complexes in organic synthesis, part 69. Total synthesis of the Amaryllidaceae alkaloids anhydrolycorinone and hippadine using iron-and palladium-mediated coupling reactions
A novel synthesis of the Amaryllidaceae alkaloids anhydrolycorinone and hippadine has been developed using an iron-mediated oxidative alkylamine cyclization and an intramolecular palladium-mediated biaryl coupling as the key steps.
(+)-γ-Lycorane has been synthesized in ten steps from piperonylic alcohol. Two radical reactions were used successively to build the D and B rings. A formal synthesis of (+)-γ-lycorane was achieved via an optically active unsaturated aldehyde intermediate