Novel Synthetic Approach towards Amino‐Substituted Polycyclic Aromatic Hydrocarbons through Electrocyclization of Keteniminium Salts

Polycyclic aromatic hydrocarbons (PAHs) are an important family of molecules in science and technology. Amino‐substituted PAHs are promising building blocks to create attractive molecules for materials science. However, the synthetic limitations have hampered to produce diverse structures of amino‐substituted PAHs. Here we describe a novel efficient synthetic method to access amino‐substituted PAHs through the electrocyclization of highly reactive keteniminium species. We demonstrated the synthesis of various amino‐substituted PAHs and disclosed some of their photophysical properties. Furthermore, combination with theoretical calculation revealed that the multiple electrocyclization reactions of keteniminium species is a stepwise process and the fusion of additional aromatic ring to the substrate accelerates the electrocyclization.