Synthesis And Properties Of The Chemosensor Based On Functionalized 1,8-Naphthalimide Schiff Base

Ion recognition is an important content of supramolecular chemistry research.Naphthalimide derivatives have good optical performance,they are widely used in the field of ion recognition;In addition,Schiff Base compounds are good ligands for their special structure.Schiff Base compounds contained different groups can be achieved for the detection of different ions.Accordingly,we consider to combine naphthalimide structure with Schiff Base structure into the same molecule,this molecule has the characteristics of naphthalimide and Schiff Base structure.It is expected to have a better effect on ion detection.In our work,we mainly designed and synthesized two kinds of sensor molecule H1 and HB1,and then studied the ability of their ion recognition.It could be divided four sections:Section one We firstly discussed the significance of supramolecular chemistry and ion recognition.Then,the applications of naphthalimide and Schiff Base in the field of ion recognition were mainly introduced.Section two A sensor molecule H1 based on functionalized 1,8-naphthalimide Schiff Base was designed and synthesized.Then,the response of H1 to various metal ions in DMSO/H₂O（7:3,v/v）solutionswasinvestigated.H1 showed fluorescence-colorimetric dual channel identification ability for Fe³⁺.When added 1equiv of Fe³⁺to the solution of H1,the fluorescence of the H1 solution quenched and the color of the solution disappeared.The result of anti-disturbance experiment demonstrated that the process of sensing Fe³⁺had good anti-interference.The titrations experiments were used to study the fluorescence spectra and UV-vis absorption spectra detection limits,the results are 3.04×10^-88 mol L^-11 and 2.71×10^-6mol L^-1,respectively.FT-IR spectroscopy and HRMS were used to consider the mechanism of H1 to Fe³⁺.These results proved the coordination effect between H1 and Fe³⁺.In the end,the test strips based on H1 were prepared,they could conveniently and rapidly detect Fe³⁺in water in different concentrations.Section three A novel sensor molecule HB1 based on 4-（Diethylamino）-2-（hydroxy）-phenyl imine functionalized naphthalimide was synthesized.And then the response of HB1 to various anions in DMSO/H₂O（8:2,v/v）solutions were considered.The results showed that the sensor could detect toxic ion-CN^-in fluorescence.When 5 equivs of CN^-added into the solution of HB1,the fluorescence intensity of the solution enhanced.Anti-interference experiment results indicated that this test process had good anti-interference.HB1 has high sensitivity for CN^-,the fluorescence detect limit of the HB1 for CN^-is 6.30×10^-88 mol L^-1.¹HNMR,ESI-MS,UV-vis absorption spectroscopy were used to explore the sensing mechanism of HB1 to CN^-.The results showed that this is a kind of deprotonation mechanism.Meanwhile,the solution of HB1 could efficiently detect CN^-in food samples.In the end,the test strips based on HB1 were prepared,they can efficiently detect the CN^-in water.Section four The test ability of HB1 to various cations was further investigated.HB1 has fluorescence-colorimetric dual channel identification ability for Fe³⁺in DMSO solution.When added 2 equiv of Fe³⁺to the HB1 solution,different from the sensor H1,the fluorescence of the HB1 solution quenched but the color of the solution changed from yellow to dark-green.The results of anti-disturbance experiment demonstrated that the process of sensing Fe³⁺had good anti-interference.The detection process has high sensitivity,the fluorescence spectra and UV-vis absorption spectra detection limits are 3.95×10^-88 mol L^-1和6.14×10^-66 mol L^-1,respectively.FT-IR spectroscopy and ESI-MS were used to consider the mechanism of HB1 to Fe³⁺.These results proved the coordination effect between HB1 and Fe³⁺.In the end,the test strips based on HB1 were prepared,they could conveniently and rapidly detect Fe³⁺in environment.