Efficient Visible‐Light‐Induced π‐Extension of Perylene Tetraesters: An Investigation on Regioselectivity

Abstract The present study discloses a highly efficient visible‐light‐induced π‐extension of perylene tetraesters and discussion on the regioselectivity in the photocyclization. We initially found that π‐extension reaction of 3,4‐dimethoxyphenyl perylene tetraester smoothly proceeded by only irradiating blue LED with a complete regioselectivity. Investigations of the photocyclization with various substrates revealed the relationship between the regioselectivity and electron‐donating/withdrawing effects of the substituents on the aromatic groups. Moreover, theoretical investigation suggested the importance of bond alteration in the aromatic groups: cyclization proceeds preferentially at shorter C−C bonds with higher double bond characters. The findings will open new possibilities for the practical synthesis of custom‐designed π‐extended perylene materials.