A total synthesis of ellipticine could be attained through the palladium catalyzed tandem cyclization-cross-coupling reaction of indolylborate (2b) with vinyl bromide (3) as a key reaction.
Ishikura, Minoru,Hino, Ayako,Katagiri, Nobuya
p. 11 - 14
(2007/10/03)
A novel entry to pyrido[4,3-b]carbazoles: An efficient synthesis of ellipticine
The palladium catalyzed tandem cyclization-cross-coupling reaction of indolylborate (2) with vinyl bromide (9) was developed for the preparation of pyrido[4,3-b]carbazole as a key reaction. The cross-coupling reaction of 2a provided hexatriene (10), and then cyclization of 10 to pyrido[4,3- b]carbazole (12) was effected with irradiation or Lewis acid. Using indolylborate (2c) for the cross-coupling reaction, a novel construction of ellipticine was attained through similar reaction sequences.