Marcos Humanes, Jaime Mateos-Gil, Francisco Mendicuti, Manuel A Fernández-Rodríguez, Patricia García-García
A modular, metal-free, cascade cyclization of functionalized enynes provides rapid access to structurally diverse boron-doped polycyclic aromatic hydrocarbons. The method simultaneously constructs the polycyclic framework and B-O, B-N, or C-B bonds while allowing straightforward boron functionalization. The alkene substitution pattern dictates the cyclization pathway, enabling selective formation of five- or six-membered rings. Photophysical studies reveal how structural variations govern the optical and fluorescence properties of these π-conjugated materials.