Studies On Design,Synthesis And Properties Of 9,10-Dithienylanthracene-type AIE Small Molecules

The concept of aggregation-induced emission(AIE)has greatly improved the limitation of application of traditional organic fluorescence materials due to the aggregation-induced quenching.Since the concept was first proposed by academician Tang Benzhong in 2001,a large number compounds with AIE have been synthesized and widely used in the fields of stimuli response,ion sensors,biological imaging and optical devices.Among those AIE materials,numbers of 9,10-distyrylanthracene AIE compounds with anthracene as the core have been reported,while 9,10-dithienylanthracenes with AIE properties have rarely been reported.In our previous work,we found that 9,10-dithienylanthracene had obvious AIE property and good biocompatibility,which could be used for cell fluorescent imaging.Therefore,in order to further systematically study the relationship between the structure and properties of them,we designed and synthesized a series of AIE compounds with multicolor luminescence through structural modification based on9,10-dithienylanthracene parent molecular.The effects of substituents,conjugated chains on their AIE and mechanofluorochromic properties,and the applications in cell fluorescence imaging were investigated.The specific research contents are as follows:1.Blue fluorescence AIE compounds based on 9,10-dithienylanthracene,including BMPTA,BPTA and BCPTA were designed and synthesized.The crystal data displayed BMPTA and BPTA had nonplanar conformations because of the multiple intermolecular hydrogen bonding interaction between the adjacent molecules,which restricted their intramolecular rotation and enabled them to emit intensely.Additionally,both BMPTA and BPTA exhibited reversible mechanofluorochromic performance by grinding-fuming,which was systematically investigated with powder X-ray diffraction,and photoluminescent lifetime.The results showed that substituent groups had significant influence on their molecular packing,mechanofluorochromic and AIE properties.Furthermore,these 9,10-dithienylanthracene luminogens could be applied in cell imaging as fluorochrome.2.Green fluorescence AIE compounds based on 9,10-dithienylanthracene,including DTA-BO and DTA-BT were designed and synthesized,which possessed aggregation-induced emission behavior and high fluorescence quantum yields in the condensed state.In addition,they displayed reversible mechanofluorochromic performance by grinding-fuming,and the powder X-ray diffraction analysis was further studied to perform the mechanofluorochromic phenomena.Intriguingly,DTA-BO and DTA-BT exhibited excellent bioimaging performance and could be applied in cell imaging.This work will be helpful for designing functional AIE dyes based on 9,10-dithienylanthracene-skeleton.3.AIE compounds based on 9,10-dithienylanthracene,including DTA-F,DTA-BF,DTA-N and DTA-BN were designed and synthesized,systematic investigated the influence of ethylene dicyano to the photophysics properties.DTA-F,DTA-BF,DTA-N and DTA-BN were displayed obviously AIE behaviors,and their solid state fluorescence color were showed blue,green and red,respectively.In addition,DTA-F and DTA-N were performed reversible mechanofluorochromic property,which was further investigated by X-ray diffraction analysis.Mostly,DTA-F,and DTA-N could enter He La cells and exhibited excellent bioimaging performance.