Differentially substituted indolocarbazoles are readily prepared via a synthetic route employing two palladium catalyzed reactions. First, biindoles are prepared from a palladium catalyzed cross coupling reaction. Second, a new palladium catalyzed benzannulation reaction employing biindolyl iodides and alkynes provides indolocarbazoles.
[Merlic, Craig A.; You, Ying; McInnes, Daniel M.; Zechman, Andrea L.; Miller, Michael M.; Deng, Qiaolin Tetrahedron, 2001 , vol. 57, # 24 p. 5199 - 5212]
