Novel Functional Hexaarylbenzene Derivatives: Synthesis And Properties Of Hexakis [3-(3'-Thienyl) Phenyl] Benzene Derivatives

As a class of emerging aromatic compounds, hexa-substituted benzene (HSB) derivatives have attracted increasing attention due to their potential function. Hexaarylbenzene derivatives, one of the representatives of such compounds, could self-assemble into one-dimensional columnar structures via intrinsic strongπ-πstacking interactions, and were consequently widely utilized in the fabrication of new functional materials as the excellent self-assembly building-blocks. So far the study mostly focused on the hexasubstituted benzene derivatives on para-position of phenyl group, however rarely investigation about the effect of meta-substituents on the properties was reported.On the other hand, thiophene and polythiophene derivatives show excellent electrochemical, optical, physical and biological properties, which also play an important role in materials science and pharmacy. Therefore, the introduction of thiophene units into the hexaphenylbenzene structure expectly manifest out new physicochemical properties, self-assembly performance and application prospect.The thesis is divided into three parts. Part I:synthesis of hexaarlybenene derivatives. With 1-bromo-3-iodobenzene as starting material,3,3'-dibromodiphenylacetylene was obtained via Sonogashira coupling reaction. Then Suzuki coupling reaction of 3,3'-dibromodiphenylacetylene with corresponding boronic acid or boronic acid esters gave a series of diarylacetylenes. By subsequently catalyzed the corresponding diarylacetylene with Co2(CO)8, we firstly synthesized the novel high soluble hexakis[3-(3'-thienylphenyl)]benzene in high yield.PartⅡ:The physicochemical properties of the hexaarylbenzenes. From the measurement results of NMR and UV, we found that compounds in the selected solvent did not exist in monomer but in certain aggregates; TGA results suggested their high thermostability; and DSC and POM results indicated that no liquid crystal phase appeared within testing temperature range.PartⅢ:Functional aspect of the novel hexaarylbenzenes. The coordination of synthesized hexaarylbenzene with silver salt by titration experiment was discussed. The results of UV and NMR measurements implied that the coordination was faild. We presumed the possible reason is that high steric hindrance and adopted conformation of molecule are unfavorable to coordinate.