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Novel naphthalene diimides and a cyclophane thereof: synthesis, characterization, photophysical and electrochemical propertiesThis paper is dedicated to Professor Jean Kossanyi on the occasion of his 70th birthday.

Department of Chemistry, Mersin University, Zephyrium, Mersin, Turkey
Photochemical and Photobiological Sciences (Impact Factor: 2.27). 04/2003; 2(3):218-23. DOI: 10.1039/B208856H
Source: PubMed

ABSTRACT

Three novel naphthalene diimides (1-3) and a cyclophane (4) containing two naphthalene diimide moieties were synthesized and characterized. In contrast to the absorption spectra, the emission spectra were strongly dependent on the solvent polarity. The excimer-like emission and low fluorescence rate constant suggest the formation of ground state complexes in DMF. All the compounds have low fluorescence quantum yields (0.001-0.012). They undergo reversible electron reduction and oxidation while deltaEp values depend strongly on solvent polarity. The LUMO energy values of 1 (3.76 eV), 2 (3.69 eV), and 3 (3.66 eV) vary with the substituent pattern. The structurally relatively rigid cyclophane 4 exhibits excellent thermal stability, a high glass transition temperature (tg, 102 degrees C) and a low LUMO energy value (3.59 eV). Compound 2 is insoluble in DMF at room temperature, but begins to dissolve at 37 degrees C and could therefore potentially serve as a sensor in temperature-sensing devices.

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