Design,Synthesis,Self-assembly And Properties Of Coumarin,Coumarin-Rhodamine,Porphyrin And BODIPY Derivatives

Liquid crystal(LC)is an intermediate phase between solid and liquid.Liquid crystal combines the order of crystals with the fluidity of liquids.It has structural self-healing ability and can respond to external factors such as electric or magnetic fields.LC has been widely used in electronic devices.Discotic liquid crystals and polycatenar liquid crystals are two important types of liquid crystals.Discotic liquid crystals have been shown to have enhanced carrier mobility,and a variety of complex microscopic self-assembled structures have been discovered.In this paper,porphyrin,coumarin and BODIPY with excellent photoelectric properties were introduced into discotic LCs and polycatenar LCs respectively.It is hoped to give these three types of liquid crystals more excellent photoelectric properties,and it is expected to obtain more complicated micro-self-assembled structures.In addition,this paper combines coumarin with red dye Rhodamine to synthesize a series of fluorescent probes with excellent performance.The first chapter is the synthesis and self-assembly of coumarin liquid crystal molecules.Firstly,the research progress of coumarin liquid crystals is reviewed,mainly from the coumarin small molecule liquid crystal and polymer liquid crystal.Based on literature research:the reported coumarin liquid crystal compounds are almost all terminal linking groups,which can self-assemble to exhibit various liquid crystal phases;the two small-molecule coumarin liquid crystalline compounds synthesized in this chapter can exhibit nematic phase and columnar phase respectively.The number and length of side chains of coumarin unit determinethe structures of the liquid crystal phases.The second chapter introduces the design,synthesis and identification of metal ions based on coumarin-rhodamine probes.Firstly,the research progress of rhodamine probes in recent years is briefly reviewed,mainly from the identification of different metal ions and the types of different linking groups.In this chapter,a new rhodamine-triazole-coumarin hybrid A and B was synthesized by using CuAAC reaction,in which the rhodamine unit was linked to the coumarin by 1,2,3-triazole.To the best of our knowledge,rhodamine has not been reported to be linked to the 4-position of the coumarin ring.The novel rhodamine-triazole-coumarin probe A containing a 7-OH group can be used as a fluorescent"Off-On" chemical sensor for Pb2+ with high selectivity and sensitivity.In addition,while probe B has a specific recognition of trivalent chromium ions.The effect of the 7-OH group on the properties of the chemical sensor on the coumarin ring was discussed.The bioimaging application of A to Pb2+ in living cells was also confirmed by fluorescence microscopy.The third chapter is the synthesis,self-assembly,ion recognition and photoelectric properties of thienoporphyrin discotic liquid crystalline molecules.Firstly,the research progress of porphyrin liquid crystals is reviewed,mainly from the different substitution positions of porphyrins,ie meso-substitution and ?-substitution.Based on literature research:he reported porphyrin liquid crystalline compounds are almost always linked by ester bonds or amide bonds to the peripheral alkyl chain,which can self-assemble to exhibit a column phase or a disk-like nematic phase.The thiophene porphyrin discotic compound synthesized in this chapter exhibits a hexagonal column phase with Zn coordination energy.The fourth chapter is the preliminary synthesis of BODIPY polycatenar liquid crystaline compounds.It mainly introduces the research progress of BODIPY liquid crystalline compounds,the progress of BODIPY type photosensitizers,the synthesis experiments of the designed target compounds and the study of BODIPY as photosensitizers.The fifth chapter is the experimental part.The synthesis steps and partial spectrum data of various compounds are introduced in detail.