Photochromism And Ion Recognition Properties Of Diarylethenes Based On Ugi Reaction

Since the 21st century,photochromic materials have been the favour of the researchers because of its simple operation,high resolving power and the ability to be used repetitively.Among the numerous photochromic systems,diarylethene photochromic compound has been standing out with its good thermal stability,good fatigue resistance and fast response.It has been widely used in photoelectric switches,optical memory materials,optical storage and other fields.Meanwhile,anion plays a significant role in the life science,chemistry and other fields,which makes the detection and identification of it being important.Therefore,it has great significance to design and synthesize new diarylethene photochromic compound with the function of anion recognition.The research of this dissertation took the dithienylethene molecule as the basic structure unit to synthesize a series of amide bridging with different aromatic ring of unilateral and bilateral dithienylethene compounds through the Ugi four components reaction.Then we studied their properties of photochromism,fluorescent and the identification of the anion recognition.The specific research contents are as follows:1.A series of amide bridging with different aromatic ring of unilateral and bilateral dithienylethene compounds were synthetized.Meanwhile,the research characterizes their structures with 1H NMR、13C NMR,mass spectrometry and element analysis.2.The properties of photochromic and fluorescence of the series of compounds were studied.The results can be summarized as:for the photochromism,when the aromatic ring was in the form of bilateral access,the photochromic properties of the compounds would be worse with the increase of aromatic ring conjugate system;when the aromatic ring was in the form of unilateral access,the photochromic properties of the compounds would generally be more superrior than its corresponding bilateral material.For the fluorescence,under the UV irradiation,the fluorescence quenching degree of the bilateral access form of compound Ⅱ-1,Ⅱ-2 and Ⅱ-3 were much less than the unilateral access form compound Ⅱ-4,Ⅱ-5 and II-6.3.The anion recognition properties of the series of compounds were studied.The results show that the compounds of Ⅱ-1,II-4 containing naphthalene ring had weak recognition effect on the OAc".Compounds of Ⅱ-2,Ⅱ-5 containing anthracene ring had a significant recognition effect on I",showed significant fluorescence emission quenching.Compounds of II-3,II-6 containing pyrene ring had good recognition effect on F".What’s more,II-3 and II-6 showed good color identification to F,while the solution after recognition of F" showed a color of greenyellow.In addition,after the identification of anions the photochromic properties of the target compounds changed much,notably the change of pyrene ring compounds II-3 and Ⅱ-6 were most obvious.