Anthracene Fluorescent Probes For Metal Ions: Molecular Design, Synthesis And Properties Investigation

As an important component of the supermolecular chemistry, the fluorescence molecular switch has developed rapidly and become interest of the chemists. In this dissertation the functional design and the molecular recognition of anthracene fluorescent receptors were studied deeply according to the trend in this field.A fluorescent probe with two anthracene groups linked by diphenyl sulfone was designed. It was found that this probe exhibit fluorescence enhancement response to Hg²⁺ and fluorescence quenching to Cu²⁺.In order to recognize the transition and the heavy metal ions, six of anthracene fluorescent probes with sulphur containing receptors were synthesized. The titration experiments indicated that the fluorescent probes are highly selective to Cu²⁺ and Hg²⁺. As a result, 9,10-bis(4-nitrobenzylthiomethyl)anthracene was designed and a 429-folds fluorescence enhancement response to Hg²⁺ was found. It was proposed that the enhancement mechanism is a typical PET-suppressed process.Two fluorescent probes with each having two dithiocarbamates groups as receptors were designed. The titration experiment indicated that these probes are highly selective to Hg²⁺, which shows a pronounced fluorescence enhancement. It was also found that the response to Hg²⁺ is a typical PET-suppressed process.Seven of bisanthracene fluoresent probes linked by different heterochain receptors were designed. The titration experiment indicates that only the sulfur containing fluorescent probes show evident fluorescence quenching upon additional Cu²⁺ and Hg²⁺. The stoichiometry of the probe-metal ion complex was estimated to be 1:1 by a nonlinear curve fitting of the fluorescence titration.Two heterochain linked bispyrene fluorescent probes were synthesized. It is found that when 3,6-dithia-l,8-diaminooctane is used as spacer and acceptor, the probe can recognize Cd²⁺, Cu²⁺, Ag+ and Hg²⁺ respectively.