Study On Synthesis And Properties Of Fluorescence Probe Molecules Based On Thieno[2,3-b]thiophene

In modern analysis science, it is a distinguished feature to show molecular recognitionfunction in the sensitive and easy testing signal. Furthermore, the chemical testing methodbased on fluorescence changes of Donor/Acceptor happened to be with this just characteristic.For this reason, the fluorescent chemical sensors become a hotspot of studying synthesis andapplication for recent years. At present, the study of organic small molecules as the carriers offluorescent chemical sensors is very active. Especially, it is the design and synthesis ofcolorimetric fluorescent sensors and the ones with novel biocompatibility organic moleculesas carriers that caused greater interest of the researchers. Many fluorescent chemical sensorsmoleculars contain pyrrole, furan or thiophene. According to Hückel Rules, the aboveheterocyclic compounds are aromatic ones. Moreover, thiophene has the highest density ofelectron cloud among the three compounds, which gives it unique optical properties and theelectronic transmission ability. Because of the advantages of higher chemical stability andsimple synthesis method, thiophene compounds are widely used in various fields, such asdrug design, dye chemistry, biological diagnoses, electronic and photonic devices,self-assembly supramolecular structure and sensing devices. Therefore, they become thefocus of the researchers.So far, there have been many thiophene derivatives with superior performance weresynthesized. Among all kinds of thiophene derivatives, thieno[2,3-b]thiophene, whichbelongs to polycyclic aromatic hydrocarbons, has large electronic conjugate system. Hence, itmay be a good choice to make them as the fluorophore of fluorescence chemical sensormoleculars.In this paper, we designed and synthesized six novel fluorescent probe molecules, whichcontained thieno[2,3-b]thiophene as fluorophore and chromophore. List as follows, sodium3,4-bis((benzo[d]thiazol-2-ylthio)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate, diethyl3,4-bis((2,3-dioxoindolin-1-yl)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate, diethyl3,4-bis((2-aminophenoxy)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate, sodium3,4-bis((quinolin-8-yloxy)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate,13,13’-(2,5-bis(4-nitrophenyl)thieno[2,3-b]thiophene-3,4-diyl)bis(methylene)bis(1,4,7,10-tetraoxa-13-azacyclopentadecane) and tetraethyl2,2’,2’’,2’’’-(2,5-bis(4-nitrophenyl)thieno[2,3-b]thiophene-3,4-diyl)bis(methylene)bis(azanetriyl)tetraacetate. Furthermore, we characterized their structures.We found that two of them could distinguish some metal ions selectively. One is sodium3,4-bis((benzo[d]thiazol-2-ylthio)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate, whichcould identify and examine lead ions in physiological conditions. The studies showed that this was based on the mechanism of photo-induced electron transfer (PET) fluorescent signalrespond. The other is diethyl3,4-bis((2,3-dioxoindolin-1-yl)methyl)thieno[2,3-b]thiophene-2,5-dicarboxylate, which could distinguish zinc ions with ratiometric fluorescence inacetonitrile solution powerfully.