Synthesis And Properties Study Of Thiophene Derivatives With Aggregation-induced Emission

Aggregation induced luminescent material is a new type of organic luminescent material which has no fluorescence in solution and produces strong fluorescence in aggregation state.The discovery of AIE materials is expected to solve the internal contradiction between ordered self-assembly and emission property.Cyanodistyrene group is a typical group with aggregation induced luminescence effect,which has potential applications in optics,electronics,energy and biological science.In this thesis,4-amino-?-(2-thiophene methylene)phenylacetonitrile with AIE effect was designed and synthesized.By introducing different liquid crystal units through nucleophilic addition reaction,new liquid crystal molecules with good AIE performance and liquid crystal performance were obtained.By introducing different groups,new AIE functional molecules with good specific recognition ability were obtained.Firstly,A new type of linear conjugated Schiff base(z)-2-(4-((E)-pyridine-2-yl-methylamino)phenyl)-3-(thiophene-2-yl)cyanoethylene(compound 3)with aggregation induced luminescence(AIE)was designed and synthesized.The reaction of compound 3 with Cl O^-resulted in fluorescence quenching.It was found that compound 3 had a good recognition effect on Cl O^-.Secondly,A new type of linear conjugated Schiff base(z)-3-(thiophene-2-yl)-2-(4-((E)-thiophene-2-methyl)phenyl)cyanoethylene(compound 4)with aggregation induced luminescence(AIE)activity was designed and synthesized.The complex of compound 4 with Hg²⁺and N₂H₆²⁺resulted in enhanced fluorescence.It was found that compound 4 had a good recognition effect on Hg²⁺and N₂H₆²⁺.Thirdly,Schiff base cholesterol liquid crystal compounds 8 and 9 were designed and synthesized.It is found that compounds 8 and 9 have good AIE and liquid crystal properties,and liquid crystal properties with more cholesterol are better,but the AIE properties are reduced.Fourthly,The Schiff base liquid crystal compounds 12 and 13 with 1 and 2flexible chains were designed and synthesized.It is found that compounds 12 and 13have good AIE properties and liquid crystal properties,and the liquid crystal properties with more alkyl groups are poor,but the AIE properties are improved.