A novel fluorescent probe,6-(N,N-dimethylamino)-2-naphthoylacryl acid(ACADAN) was designed and synthesized as a fluorescent sensor for Cu^2+ in aqueous media.Significant amplification of fluorescence signals with...A novel fluorescent probe,6-(N,N-dimethylamino)-2-naphthoylacryl acid(ACADAN) was designed and synthesized as a fluorescent sensor for Cu^2+ in aqueous media.Significant amplification of fluorescence signals without causing any discernible change of maximum fluorescence emission wavelength(λ max) was observed upon the addition of Cu^2+.Importantly,ACADAN is capable of recognizing Cu^2+ selectively in aqueous media in the presence of various biologically relevant metal ions and the prevalent toxic metal ions in the environment with high sensitivity(detection limit was 0.1 μmol/L).展开更多
Since tertiary amines (Cα-H) can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2+ radicals to initiate vinylic polymerizations of methacrylates, Cu2+ and 2-(N,N-dimethylam...Since tertiary amines (Cα-H) can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2+ radicals to initiate vinylic polymerizations of methacrylates, Cu2+ and 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA) form a polymerizable redox initiating pair, in which DMAEMA serves as an intrinsically reducing inimer. CuSOa-catalyzed aqueous self-initiated radical polymerizations of DMAEMA were successfully performed at ambient temperature via a continuous Cu2+-tertiary amine redox initiation based on catalyst regeneration in the presence of O2. The polymerization kinetics was monitored by gas chromatography and the structure of PDMAEMA was characterized by gel- permeation chromatography, nuclear magnetic resonance spectroscopy, laser light scattering and online intrinsic-viscosity analysis. Both the monomer conversion and the molecular weight of PDMAEMA increase with the reaction while the molecular weight distribution maintains rather broad, as the Cu2+-DMAEMA redox-initiation leads to linear PDMAEMA chains with terminal methacryloxyl moieties, and the Cu2+-PDMAEMA redox-initiation results in branched chains. The branched topology forms and develops only for the high-MW components of the PDMAEMA. Our results provide a facile strategy to prepare branched polymers from such commercially available intrinsically reducing inimers using a negligible concentration of regenerative air-stable catalysts.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.30672560,81172982)the Accented Project for Natural Scientific Research of Universities in Guangdong Province,China(No.05Z012)
文摘A novel fluorescent probe,6-(N,N-dimethylamino)-2-naphthoylacryl acid(ACADAN) was designed and synthesized as a fluorescent sensor for Cu^2+ in aqueous media.Significant amplification of fluorescence signals without causing any discernible change of maximum fluorescence emission wavelength(λ max) was observed upon the addition of Cu^2+.Importantly,ACADAN is capable of recognizing Cu^2+ selectively in aqueous media in the presence of various biologically relevant metal ions and the prevalent toxic metal ions in the environment with high sensitivity(detection limit was 0.1 μmol/L).
基金financially supported by the National Natural Science Foundation of China(No.20674033)Natural Science Foundation of Jiangsu Province(No.BK2008142)Scientific Research Foundation for the Returned Overseas Chinese Scholars(State Education Ministry)
文摘Since tertiary amines (Cα-H) can be oxidized by peroxides and transition metal cations in high oxidation states into Ca2+ radicals to initiate vinylic polymerizations of methacrylates, Cu2+ and 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA) form a polymerizable redox initiating pair, in which DMAEMA serves as an intrinsically reducing inimer. CuSOa-catalyzed aqueous self-initiated radical polymerizations of DMAEMA were successfully performed at ambient temperature via a continuous Cu2+-tertiary amine redox initiation based on catalyst regeneration in the presence of O2. The polymerization kinetics was monitored by gas chromatography and the structure of PDMAEMA was characterized by gel- permeation chromatography, nuclear magnetic resonance spectroscopy, laser light scattering and online intrinsic-viscosity analysis. Both the monomer conversion and the molecular weight of PDMAEMA increase with the reaction while the molecular weight distribution maintains rather broad, as the Cu2+-DMAEMA redox-initiation leads to linear PDMAEMA chains with terminal methacryloxyl moieties, and the Cu2+-PDMAEMA redox-initiation results in branched chains. The branched topology forms and develops only for the high-MW components of the PDMAEMA. Our results provide a facile strategy to prepare branched polymers from such commercially available intrinsically reducing inimers using a negligible concentration of regenerative air-stable catalysts.