Research On Recognitions And Properties Of CN~- Based On Azine Derivatives And Rhodamine B Compound

It’s well known that cyanide is toxicity to people,when it enters the human body;it affects the Body’s central nervous system and metabolic system,which will light lead to nausea,headache,weakness of limbs,and severe coma,convulsions,and sudden drop in Blood pressure,the breath stops and dies.However,cyanide is closely related to people’s production and life,and is widely used in electroplating,mining,metallurgy,medicine and pesticide production,which brings serious pollution to the environment.Therefore,the development of high sensitivity and high selectivity determination of trace cyanide sensors is very important in environmental monitoring and food analysis.In view of this,we designed and synthesized three CN^-sensors in this paper,and study its anions recognition properties.The thesis consists of four parts:Chapter one:IntroductionThis chapter introduces the background of supermolecular chemistry,the mechanism and significance of ion recognition,the significance of cyanide recognition,and introduces detailedly the research progress of CN^–recognition,and summarizes five kinds of CN^–sensors:（1）Deprotonation-type CN^–sensor;（2）Hydrogen Bond-type CN^–sensor;（3）Nucleophilic addition Based CN^–sensor;（4）Coordination-type CN^–sensor;（5）other recognition mechanism.Chapter two:Synthesis and Research on recognitions and properties of asymmetric douBle-azine sensor L1 Based on 1,4-Phthalaldehyde groupIn this chapter,we have designed and synthesized an asymmetric double-azine sensor L1Based on1,4-phthalaldehyde and salicylaldehyde hydrazone,which showed both“naked eye”recognition and fluorescence“on-off”responses for CN^-in DMSO/H₂O（v/v=4:1,pH=7.20）solution.This simple sensor L1 could distinguish CN^-from coexisting anions via the way of deprotonation and sensing mechanism of intramolecular charge transfer（ICT）,and the minimum detection limit on fluorescence response of the sensor L1 towards CN^-was down to 9.47×10^-7M.which is far lower than the maximum level of 1.9×10^-6M for cyanide in drinking water according to WHO guidelines,According to the data of ¹H NMR titration and Job curve,it is indicated that the sensor L1 and CN^–are reacted with 1:2.Moreover,we have successfully utilized the sensor L1 to detect CN^-in bitter almond.Test strips containing L1were also prepared,which could act as a practical colorimetric tool to detect CN^-in aqueous media.Chapter three:Synthesis and Research on recognitions and properties of azine sensor PX Based on quinoline-2-formaldehyde groupIn this chapter,we used salicylaldehyde hydrazone and quinoline-2-formaldehyde as raw materials to synthesize a simple structure sensor PX,which showed both colorimetric and“turn-on”fluorescence responses for CN^-in DMSO/H₂O（3:2,v/v）solution.and other competitive anions（F^-,Cl^-,Br^-,I^-,AcO^-,H₂PO₄^-,HSO₄^-,ClO₄^-and SCN^-）do not interfere with the recognition of CN^–,after the addition of CN^-,the solution of PX changed from colorless to yellow,and the UV absorption peak of the host PX showed a red shift phenomenon,the fluorescence intensity of the host PX was enhanced by 55 times in the fluorescence spectrum.And the minimum fluorescence detection limit on the sensor PX towards CN^-was down to 4.5×10^-7M.According to the data of¹H NMR titration and Mass spectra,the probe could distinguish CN^-via deprotonation process and the sensor PX and CN^–are reacted with 1:1,Moreover,we have successfully utilized the sensor PX to detect CN^-in bitter almond.Test strips containing PX were also prepared,which could be used as a practical colorimetric method for the determination of CN^-in aqueous system.Chapter four:Study on Synthesis and recognitions properties of sensor PW Based on8-（7-hydroxy-4-methyl-8-formyl）rhodamine B hydrazideIn this chapter,we designed and synthesized a novel sensor PW,which displayed both colorimetric and“turn-on”fluorescence responses for CN^-in DMSO/H₂O（1:1,v/v,）solution,and other competitive anions（F^-,Cl^-,Br^-,I^-,AcO^-,H₂PO₄^-,HSO₄^-,ClO₄^-and SCN^-）do not interfere with the recognition of CN^–,The probe could distinguish CN^-via deprotonation process,and reacted CN^-by 1:1,which was proved by¹H NMR titration,ESI-MS and Job curve.Moreover,the detection limit on fluorescence response of sensor PW towards CN^-was 1.592×10^-7M.Above all;we have successfully utilized the sensor PW to detect CN^-in bitter almond.Test strips containing PW were also prepared,which could act as a practical colorimetric tool to detect CN^-in aqueous media.