Design, Synthesis And Properties Of Novel Fluorescent Dyestuff And Fluorescent Probes Based On4-amine-naphthalimide And Perylene Diimide

With the pursuit of human exploration of science, organic fluorescent dyes, which have a broadapplication prospect in industry, agriculture, medicine, textile, energy, defense and gene biology, have beenwidely used in coatings, printing ink, paper, food, plastics, detergents, cosmetics, and the textile industry.4-amino-1,8-naphthalimide derivatives are attractive molecular building blocks that have beenextensively investigated for use in a variety of photoactive organic materials.1,8-naphthalimidederivatives with good rigidity and coplanar, and simple structure, easy modification on the molecularstructure, high luminescence efficiency, large stokes shift have been widely used in industrial fluorescentdye, photovoltaic materials, laser materials, fluorescent labeling and fluorescent probe.In the first part of our research, six4-amino-1,8-naphthalimide derivatives withdi-(2-picolyl)-amine (DPA) group through different linkers were successfully synthesized andcharacterized through1H NMR,13C NMR. The UV-vis and fluorescent spectra experiments wereinvestigated. The results showed that the different substituents of naphthalimide in the same conditions hada remarkable effect on the spectroscopic properties. By comparison, the identical substituents at4-positionof naphthalimide were more easier to cause fluorescence quenching than at N-position. In addition, bycomparing meta-position isomer and para-position isomer, we found para-position substituents ofnaphthalimide had a bigger quenching degree.Perylene tetracarboxylic diimide derivatives which were widely used as fluorophore with goodelectron accepting ability have generated great interest in the field of photonic materials, because of theirexcellent light and thermal stabilities, high fluorescence efficiency and good semiconducting properties.In the second part of our research, three PDIs derivatives PDI-1, PDI-2and PDI-3were rationallydesigned and synthesized. The PDI with four substituents at the bay positions was chosen as fluorophoreand di(2-pyridylmethyl)amine (DPA) group was used as receptor owing to their powerful chelating abilityto many transitional metal ions. The different linker, including aromatic benzyl ring, N-ethyl-aniline andsaturated ethyl groups, connected the fluorophores with DPA moieties, respectively. The results ofspectroscopy experiment revealed that PDI-1showed excellent selectivity and sensitivity for Pd2+ions over other competing metal ions in mixed aqueous media (DMF/H2O, v/v,7:1). A1:1stoichiometry was foundfor the complex formed by PDI-1and Pd2+by a Job’s plot, by non-linear least square fitting of thefluorescence titration curves and by ESI-MS. The association constant Kawas calculated to be2.24×104M-1through the Benesi-Hildebrand analysis. This is the first report of Perylene diimide based “turn-on”fluorescence sensor for detection of Pd2+in mixed aqueous media.