Photochemical Insights on Intramolecular Dye-Sensitized Free-Radical Processes with a Quinoline Antenna

Under mild ultraviolet illumination, a quinoline dye acts as a molecular ‘antenna’ to promote the reactivity of chemically coupled TEMPO toward H abstraction to form the corresponding N-hydroxylamine. The hydrogen can also be abstracted from a polymer matrix (R), and subsequent linkage of the dye-nitroxide to the polymer skeleton can occur. In all cases, the intramolecular quenching pathway is suppressed and the fluorescence of the quinoline dye is restored.