Novel and Efficient Synthetic Path to Proaporphine Alkaloids: Total Synthesis of (±)-Stepharine and (±)-Pronuciferine

Abstract

[reaction: see text] A novel synthetic path to proaporphine alkaloids was established by employing aromatic oxidation with a hypervalent iodine reagent, where an unprecedented carbon-carbon bond forming reaction between the para-position of a phenol group and an enamide-carbon took place smoothly to give the desired spiro-cyclohexadienone.