Visible-Light Auto-Catalyzed Transformation in Naphthylamines and their Spiroacridines

Visible-light-induced self-sensitization reaction are of crucial importance to understand the biological color mechanism and defect-triggered accelerating degradation and to design photocatalysis for practical application. Here, we discovered a visible-light auto-catalyzed transformation in naphthylamines and their spiroacridines. A series of spiro[fluorene-9,7'-dibenzo[c,h]acridine]-5'-one (SFDBAO) derivatives have been concisely and cleanly obtained by directly irradiating sunlight in the higher yields than that when using a UV lamp. An interesting auto-catalysed and self-sensitive procedure has been proposed to explain the effective photooxygenation. Air atmosphere and sunlight irradiations are crucial conditions of the photooxygenation reaction to obtain the high-yield products. SFDBAO derivatives exhibit the continuous