Metal-Free Visible-Light-Mediated Aromatization of 1,2-Dihydronaphthalenes
Abstract
A series of polyaromatic naphthalenes have been synthesized through the dehydrogenation of the corresponding 1,2‐dihydroarylnaphthalenes by using 9‐mesityl‐10‐methylacridinium perchlorate as a photocatalyst and diphenyliodonium triflate as an external oxidant under visible light irradiation. The reaction proceeds smoothly under metal‐free conditions and tolerates some functionalities. Interestingly, the reaction is also amenable to the aromatization of tetrahydronaphthalenes and fair conversions were obtained. Preliminary mechanistic investigations have been conducted and a reasonable mechanism is proposed.