Design,Synthesis And Self-assembly Of Triazole-porphyrin,Benzothidizole And BODIPY Based Liquid Crystals

Supramolecules are aggregates formed by non-covalent interactions with complex,organized structures.Supramolecules represent an important class of advanced functional materials,which often self-assemble into hierarchical structures from nanoscale to microscale.Liquid crystal as one of the supramolecular materials is very attractive.Liquid crystalline systems combine the ordered structure of a crystal phase with the molecular mobility of an isotropic?liquid?phase.This mobility allows liquid crystalline mesophases to self-healing structures and to responseto external factors such as electrical or magnetic fields,LCs with such characters have been widely used aselectronic devices.The discotic liquid crystals,the bolaamphiphiles and polycatenars are three important types of mesogens.The discotic liquid crystals have the ability to enhance carrier mobility.Due to its unique molecular structure and various driving forces for assembly,bolaamphiphiles and polycatenars have found a variety of complex microscopic self-assembly structures.In this paper,porphyrins,2,1,3-benzothiadiazoles and BODIPY with excellent photoelectric properties are introduced into these three types of liquid crystals respectively,and it is hoped that these three types of liquid crystals will be given more excellent photoelectric properties,and it is expected that more complicated microscopic self-assembly structures will be obtained.The first chapter is about the synthesis,self-assembly,ion recognition,and photoelectric properties of triazole-porphyrin discotic liquid crystals.Firstly,the research progress of the porphyrin liquid crystals is reviewed.The meso-substitutions and?substitutions of porphyrins are mainly described.Secondly,the research status of porphyrins in ion recognition and gels are introduced.Based on literature research:Firstly,the reported porphyrin liquid crystalline compounds are almost always connected to the peripheral alkyl chain via an ester or amide link,and can self-assemble to form column phase and nematic discotic phase;Secondly,the combination of porphyrin centers with metal ions and the combination of porphyrin-linked heteroatom groups and metal ions can lead to changes in absorption and fluorescence emission properties,so porphyrin chemical sensors can be constructed by these two combinational interactions;Thirdly,porphyrin gel-based research is still relatively small,porphyrin derivatives generally aggregate in the gel state to form a one-dimensional fiber structure and two-dimensional sheet structure,and other special structures have not been reported.The triazole-porphyrin discotic compounds synthesized in this chapter can exhibit hexagonal columnar phases in their pure states and the supramolecularcomplexesofP/18-ZnwithC₇₀or4,7-di-4-pydriyl-2,1,3-benzothadiazole can display hexagonal columnar phases too.These compounds can aggregate in 1,4-dioxane to form a unique microsphere structure,and compounds coordinating with Zn can recognize Cu²⁺in THF-H₂O solution.Studies have shown that these compounds have potential applications in the field of organic electronic devices and chemical sensors.In the second chapter,the syntheses,self-assembly and photoelectric properties of benzothiadiazole based bolaamphiphiles are introduced.Firstly,the recently research progress of bolaamphiphiles is briefly reviewed.By regulation the length,position and type of non-polar lateral chains or the length and shape of rigid cores,a variety of complex microscopic self-assembly structures can be obtained.The benzothiadiazole based bolaamphiphiles synthesized in this chapter have a rigid core with a D-A-D conjugate system and can self-assemble to form a square cylinder phase(Col_squ/p4mm),in which n-butanol can aggregate to form a three-dimensional network structure;By studying the photoelectric property of the compound,the compound has a broad absorption range,at the same time there is intramolecular charge transfer,and there is a clear solvent effect;Cyclic voltammetry and spectroscopic calculations show that the compound has a very low energy gap and can be used as a potential organic semiconductor material.The third chapter is about the synthesis of BODIPY compounds.It mainly introduces the research progress of BODIPY liquid crystals and some initial experients of the designed compounds.In the four chapter,the detail synthetic procedures and the corresponding experimental data for each compound were provided.