Total Synthesis of Benzo[c]phenanthridine Alkaloids, Chelerythrine and 12-Methoxydihydrochelerythrine, by a Palladium-Assisted Internal Biaryl Coupling Reaction
A convenient and versatile synthesis of benzo[c]phenanthridine alkaloids, chelerythrine (1) and 12-methoxydihydrochelerythrine (5), was accomplished via an internal aryl-aryl coupling reaction of haloamides 8 and 9 by a palladium-assisted cyclization reaction.