Modular Synthesis of Bicyclic and Tricyclic (Aza‐) Arenes from Nucleophilic (Aza‐)Arenes with Electrophilic Side Arms via [4+2] Annulation Reactions

• DOI: 10.1002/adsc.201900425
• Publication Date: 2019-07-13T02:48:35Z
• Authors: Wenbo Huang; Shaomin Chen; Jian Yang; Ahmed El‐Harairy; Xin Wang; Minghao Li; Yanlong Gu
• Keywords: Annulation; Trifluoromethanesulfonate; Tricyclic

Abstract An efficient strategy for the synthesis of bicyclic and tricyclic (aza‐)arenes from a nucleophilic (aza‐)arene with an electrophilic side arm was developed. The precursor has both sites, which were fixed at 1,4‐distance. products constructed via [4+2] annulation by using scandium(III) triflate as catalyst enolizable ketones or aldehydes counterpart reagents. A variety six‐membered carbocycles heterocycles, such indolizines, indoles, naphthalenes, carbazoles, pyrido[1,2‐α]indoles, successfully synthesized. Some one‐pot sequential reactions also developed, in 1,4‐donor‐acceptor precursors can be synthesized oxidation alcohols proper condensation reaction. magnified image