The colourless imidazolyl-quinoline derivatives 1 and 2 are ready utilizing a Debus−Radziszewski methodology, which proves relevant to phenanthrene- and phenanthroline-based precursors in addition to a variety of functionalized anilines, the place X = H, OMe, Cl and Br (pictured). Following ultraviolet (UV) irradiation of 1 in a combined dichloromethane and methanol answer for twenty-four h, a darkish purple species, 3, is obtained in 73% yield. Equally, 2 may very well be transformed to 4 (brilliant crimson species) in 69–93% yields. Crystallographic evaluation of 4 (the place X = H) confirms the 1,4-aryl switch response.