摘要
A novel crown ether, 2,3-naphtho-10-aza-15-crown-5 (NAC) was synthesized.This compound does not show strong fluorescence and phosphorescence due to photoinducedintramolecular electron transfer from the nitrogen lone pair of electrons to the singlet excitedstate of the naphthalene chromophore. Complexation with heavy-metal ions results in the quenching ofthe fluorescence and enhancement of the phosphorescence significantly. These observations wereinterpreted in terms of the binding interactions, between the nitrogen lone pair electrons and themetal cation, which prevent photoinduced intramolecular electron transfer, and the heavy-atomeffects which induce quenching of the fluorescence and enhancement of the phosphorescence. Theseazacrown and heavy-metal-based systems could be useful as potential chemical sensors and molecularphotonic devices.
A novel crown ether, 2,3-naphtho-10-aza-15-crown-5 (NAC) was synthesized.This compound does not show strong fluorescence and phosphorescence due to photoinducedintramolecular electron transfer from the nitrogen lone pair of electrons to the singlet excitedstate of the naphthalene chromophore. Complexation with heavy-metal ions results in the quenching ofthe fluorescence and enhancement of the phosphorescence significantly. These observations wereinterpreted in terms of the binding interactions, between the nitrogen lone pair electrons and themetal cation, which prevent photoinduced intramolecular electron transfer, and the heavy-atomeffects which induce quenching of the fluorescence and enhancement of the phosphorescence. Theseazacrown and heavy-metal-based systems could be useful as potential chemical sensors and molecularphotonic devices.
基金
theMinistryofScienceandTechnologyofChina (Nos.G 2 0 0 0 0 7810 4andG 2 0 0 0 0 775 0 2 )
theNationalNatu ralScienceFoundationofChina (Nos.2 0 0 730 5 1and 2 9972 0 4 2 )
