Abstract: A kind of open chain compounds, containing tri-, di- or mono-naphthylurea substituted amines, were synthesized in this work. It is found that the photophysical behaviors of these compounds in DMF solution strongly depend on the structure and the fluorescence intensity of tripodal compound if affected by the acidity of solution. In the same time, apparent intramolecular photoinduced electron transfer(PET) of the tripodal compound with a tertiary amine group was found, resulting in self-quenching of excited state of this compound. Furthermore, this process can be well reduced by protonation of nitrogen of the tertiary amine group of tripodal compound.

Key words: multi-podal compounds, fluorescence spectra, intramolecular photoinduced electron transfer, pH effect