Diversification of 4-bromo-1H-indole-3-carbaldehyde-derived Ugi adducts: Access to the azepino[3,4,5-cd]indoles and spiroindolines

[Display omitted] 4-Bromo-1H-indole-3-carbaldehyde has been explored as a key building block for a post-Ugi assembly of azepino[3,4,5-cd]indoles and spiroindolines. First, the corresponding Ugi adducts were successfully employed in palladium-catalyzed reductive Heck cyclization producing a range of azepinoindoles. Then, 4-bromo-1H-indole-3-carbaldehyde-derived Ugi adducts were subjected to cationic gold catalysis affording tetracyclic spiroindolines. Furthermore, the aryl bromide moiety retained in the resulting spiroindolines was found to be amendable to further functionalization via Suzuki and Sonogashira couplings.