An intramolecularly hydrogen-bonded crescent aromatic oligoamide 1 bearing two coumarin residues was syn- thesized. The results from UV-vis and fluorescent spectra upon metal ions complexation demonstrated that the tw...An intramolecularly hydrogen-bonded crescent aromatic oligoamide 1 bearing two coumarin residues was syn- thesized. The results from UV-vis and fluorescent spectra upon metal ions complexation demonstrated that the two fluorophores serving as parts of the shape-persistent backbone provided the molecule with high selectivity and sen- sitivity for recognition of Th4＋ over other lanthanide and uranyl ions. A 48-fold fluorescent enhancement in the in- tensity was observed at 505 nm upon adding Th4＋, while other metal cations failed to induce such a significant change. A visual detection for Th4＋ was achieved by color change. The stoichiometry of the complex formed by 1 and Th4＋ was found to be 1 ： 1 with the stability constant of（2.0±0.6） × 10^6 L·mol^-1.展开更多
A oligoamide with pyrazoline segment was designed and synthesized.Its structure was identified by IR,MS and 1HNMR.Fluorescence property of the target compoud in solution(DMF) was studied.The results showed that the st...A oligoamide with pyrazoline segment was designed and synthesized.Its structure was identified by IR,MS and 1HNMR.Fluorescence property of the target compoud in solution(DMF) was studied.The results showed that the strongest emission peak was at 442nm and the half peak width was 64nm and the fluorescence quantum yield(Φ) was 73.9%,which enhanced 13% compared to the simple pyrazoline structural unit′s Φ.展开更多
基金the National Natural Science Foundation of China，NSAF，Sichuan Province Science and Technology Support Programme，the National Fund of China for Fostering Talents in Basic Science，the Open Project of Key Laboratory for Radiation Physics and Technology of Ministry of Education (2010-08).Analytical & Testing Center of Sichuan University is acknowledged for NMR analyses
文摘An intramolecularly hydrogen-bonded crescent aromatic oligoamide 1 bearing two coumarin residues was syn- thesized. The results from UV-vis and fluorescent spectra upon metal ions complexation demonstrated that the two fluorophores serving as parts of the shape-persistent backbone provided the molecule with high selectivity and sen- sitivity for recognition of Th4＋ over other lanthanide and uranyl ions. A 48-fold fluorescent enhancement in the in- tensity was observed at 505 nm upon adding Th4＋, while other metal cations failed to induce such a significant change. A visual detection for Th4＋ was achieved by color change. The stoichiometry of the complex formed by 1 and Th4＋ was found to be 1 ： 1 with the stability constant of（2.0±0.6） × 10^6 L·mol^-1.
文摘A oligoamide with pyrazoline segment was designed and synthesized.Its structure was identified by IR,MS and 1HNMR.Fluorescence property of the target compoud in solution(DMF) was studied.The results showed that the strongest emission peak was at 442nm and the half peak width was 64nm and the fluorescence quantum yield(Φ) was 73.9%,which enhanced 13% compared to the simple pyrazoline structural unit′s Φ.
