Synthesis And Recognition Properties Of The Fluorescent Anion Receptors

The coordination chemistry of anions received little attention and it has only been in the last twenty years that sustained effort has been applied to the problems inherent in binding anions. Anions are ubiquitous throughout biological systems. They carry genetic information (DNA is a polyanion) and the majority of enzyme substrates and co-factors are anionic. Anions also play roles in the areas of medicine, catalysis, environments and so on.Hypochlorite (ClO-) is widely employed in our daily life. However, the abnormal production of hypochlorite can lead to a variety of diseases. Thus, it is of great interest to design and synthesize sensitive and selective probes which could detect hypochlorite by chemists. The coumarone could emit strong fluorescence and have stable structures as well as it is easy to be detected, so it is designed in the probes as the signal group. It is expected to highly select and sense ions. Most of Schiff-bases are employed to detect metal action. However, because they are easy to be synthesized and there are carbon-nitrogen double bond and hydrogen bond in the structure, they could be designed to detect anions. In this paper, the main study contents are as follows:We designed two different synthetic routes. One is to design the chemosensors which are based on coumarone, the other one is to design probes that are based on Schiff-base. Finally, we synthesized five target compounds and they are characterized by NMR、EI、MALDI-TOF-MS.We investigated the properties of five target compounds by uv-vis, fluorescence spectroscopy and NMR including selectivity and sensitivity for anions, the complexation way or mode of action, response time, detect limitation, themodynamic constants, interference experiment.The probes based on Schiff base, the compound11could be used as the fluorescent probe for CN-in CH3CN.The chemosenors based on coumarone, this is the first time that we reported the probes detected ClO-by deproteting ketone oxime to oxime. This is also the first time we reported two different compounds4and6could be used as both colorimetric and fluorescent probes for ClO-. The compounds4and6had single selectivity and high sensitivity for ClO-by utilizing the deoximation reaction of oxim groups to their corresponding aldehyde or ketone group in75%hydrous media at room temperature. The mechanism is easy. The response time is very fast within10seconds and the detect limitation could reach as low as0.2μM.