| Aggregation-induced emission（AIE）phenomenon shows colossal potential in optoelectronic materials and chemo/biosensors,and attracts more and more attentions.However,as sensors,AIE molecules have generally displayed low selectivity.Tetraphenylethylene（TPE）and its derivatives are the most studied and the easiest modified AIE compounds.As if the TPE units can be connected into cycle,the resultant macrocyclic compounds will probably exhbit high selectivity in molecular recognition due to cavity effect of the macrocycles.Moreover,the formation of rigid macrocycle will enhance the fluorescent intensity according to the AIE mechanism of restriction of intramolecular rotation.In the thesis,novel TPE tetraaylhydrazine macrocycles were synthesized and their properties including molecular recognition were studied,and some interesting results were obtained.1.Using dihydroxydibromo TPE as starting material,dipentoxydibromo TPE was prepared by etherification reaction.Treated by bis（pinacolato）diboron in the presence of Pd catalyst,dipentoxydibromo TPE was transferred into dipentoxy TPEdiborate ester,which could give dipentoxy TPEdibezoate by Suzuki reaction.With dipentoxy TPEdibezoate in hand,both dipentoxy TPEdibezoylhydrazine and dipentoxy TPEdibezoic acid were obtained by reaction with hydrazine and hydrolysis reaction,respectively.Finally,TPEtetracylhydrazine macrocycles were synthesized by condensation of the TPEacylhydrazine and TPEbenzoic acid.Three TPEtetracylhydrazine macrocycles with different sizes of cavity were designed and two of them were synthesized in about 50% yield in cyclization step.2.The TPEtetracylhydrazine macrocycles exhibited AIE,mechanochromic and solvochromic effect.By grinding,the solid macrocycles emitted yellow-green fluorescence from green-blue one.Upon fuming by methanol or ethanol,the yellow-green fluorescence could be transferred into blue one,which returned to yellow-green one after the solvent was dried up.Moreover,n-Propanol could lead the effect.Therefore,the TPEtetracylhydrazine macrocycle could be used to identify methanol,ethanol or n-propanol from other solvent and discriminate n-propanol from i-propanol.3.Nitroaromatic compounds could quench the fluorescence of the macrocycle suspension in THF-H2 O in different degree.Surprisingly,instead of trinitroaromatic compounds,nitrobenzene displayed the most quenching ability to the macrocycle fluorescence,which had a potential for selectively recognizing nitrobenzene from other nitroaromatic compounds.4.The crystal structure of one macrocycle disclosed that the macrocycle possessed rigid V-like cavity.Stacking from cavity to cavity,1D porous channel could be formed,whic h had potential for storage of materials such as CO2 adsorption. |
