Synthesis And Properties Of Salicylaldehyde Diarylethene And Pyridine Diarylethene Sensors

The design of fluorescent sensors is important for chemical and biological analyses has become a field of increasing research attention during the last decade.Moreover in this field,the design of probes displaying multi-responsive and multi-functional in optical properties have become one of the most challenging aspects.Many studies have been conducted on the use of photo-responsive materials as highly selective and sensitive chemosensors.Diarylethene derivatives offer several advantages over other photochromic systems and these advantages include fast response,excellent thermal stability and outstanding fatigue resistance.For fluorescence modulation,diarylethene probes enable a reversible signal to detection of the target ion.In this regard,the introduction of specific functional groups and conjugation with certain functional moieties have enabled diarylethenes to respond not only to UV and visible light but also to other external stimuli such as pH,cations,anions,and biomolecules.On the basis of the mentioned facts,we constructed a series of fluorescence chemosensor which can detect ions using a new photochromic diarylethene with different functional unit.The main content of this paper summarize as follow:In chapter 1,the excellent properties of diarylethene compounds,the research background of fluorescence chemosensor,the research process of the fluorescent chemosensor of structural difference and based on diarylethene were intensively introduced.In chapter 2,5-aminouracil was connected with the compounds of salicylidene diarylene and pyridine diarylethene,two diarylethene probes?DT-1 and DT-2?were synthesized.Discussed the difference of their optical properties,ionic validity recognition and pH responses.The fluorescence modulation efficiency of the DT-1 is much higher than DT-2,the difference of their ability of ion recognition is large.DT-1 could serve as a naked-eyes fluorescence chemosensor for detection of Al³⁺and Zn²⁺,and pH responses.However,DT-2 exhibited high selectivity for Zn²⁺.In chapter 3,two diarylethene derivatives DT-2 and DT-3 with a hydralazine unit were designed and synthesized,its multi-controllable switching behaviors induced by light and chemical stimuli were investigated.DT-2 exhibited high selectivity for Zn²⁺,the DT-4 was not only highly selective towards Zn²⁺,but also affinity for HSO₄^-.Interestingly,the diarylethene could be acted as a multi-functional reversibly fluorescence sensor for Zn²⁺and HSO₄^-.In chapter 4,three novel diarylethene compound DT-5 and DT-6 with hydrazinobenzothiazole Shiff-base unit were designed and synthesized.The photochromic properties and their multiple fluorescence switch induced by light and chemical stimuli were investigated.Comparison found that they both have a good photochromic ability and high fluorescence modulation efficiency.Similarly,they have a large difference of the ion recognition.DT-5 exhibited good selectivity for Al³⁺,while DT-6 can double-identify Cd²⁺and Zn²⁺.