Rhodamine, The Synthesis Of Coumarin Derivatives And Fluorescent Recognition Performance Study

Molecular fluorescent probes transfer molecular recognition events into fluorescence signals, which can be investigated by analysts. The advantages of molecular fluorescent probes for sensing can be summarized:high sensitivity,"on-off" switch ability, subnanometer spatial resolution and submilisecond temporal resolution, from the impact of electromagnetic field, remote and real time on line sensing, et al, and already have played an essential role in metal cations, anions, neutral molecules, mucleic acids, immune cells and testing.In this thesis, a general introduction to molecular fluorescent probe was presented. Emphasis was paid on research progress in rhodamine fluorescent probes. On the basis, a series of rhodamine and coumarin derivatives were designed and synthesized in this paper, and their fluorescence properties were studied.Firstly, two bis-rhodamine based fluorescent probes were synthesized, and their fluorescent properties were studied. RP1and RP2exhibit high sensitivity for sensing Fe3+in neutral pH range. RP1has some fluorescent response to Cu2+Secondly, a rhodamine-triethoxy methane conjugated fluorescent probe RP3was synthesized and the fluorescent properties were studied. RP3exhibits high sensitivity for sensing Fe+and Hg2+in neutral pH range. RP3shows high selectivity for Fe3+and poor anti-jamming ability for Hg2+。Thirdly, a rhodamine-furan conjugated fluorescent probe RP4was synthesized and the fluorescent properties were studied. RP4exhibits high sensitivity and selectivity for sensing Fe3+in neutral pH range.Fourthly, octamethyl-X-rhodamine and octamethyl-5-&-6-carboxy-X-rhodamine were synthesized and identified by’H NMR and MS.Finally, a DPA-Coumarin conjugate CP1and a bis-methylthioglycolate-coumarin conjugate CP2were synthesized and their fluorescent properties were studied. CP1exhibits high selectivity for sensing Cu2+. Upon binding Cu2+, a blue shift in fluorescence emission peak and a moderate decrease in fluorescent emission intensity were observed. CP2exhibits high selectivity for sensing Fe2+. Upon binding Fe2+, a blue shift in fluorescence emission peak and a sharp decrease in fluorescent emission intensity were observed.