Design And Synthesis Of HBC Derivatives

Since its discovery,single-layer graphene has become a research hotspot in many fields due to its excellent properties.Among them,nanographene fused aromatic hydrocarbon compounds(PAHs)have attracted wide attention.The development of new organic conjugated polycyclic aromatic hydrocarbon materials with excellent optical and electrical properties has important research significance.As a new type of quasi-one-dimensional nanomaterials,nanomaterials have unique characteristics in terms of optics,magnetism and electricity because of their unique characteristics,such as size effect,quantum effect and interface effect,which are widely concerned by scientists.Graphene nanoribbons(GNRs)are quasi-one-dimensional products obtained by limiting the width of graphene to below 50 nm.Special edge effects due to special structures(such as edge configuration,edge chaos,and different edge treatments)The influence of its properties)is the most essential feature distinguishing it from graphene and a source of many of its special properties.GNRs inherit many of the excellent properties of graphene and overcome the shortcomings of graphene zero bandgap.Therefore,compared with graphene,GNRs have greater potential practical value in the field of electronics.Adding heteroatoms to graphene nanoribbons can effectively modify and adjust the edge structure and electrical properties of graphene nanoribbons.Polycyclic aromatic hydrocarbons(PAHs)have good charge transfer characteristics and modifyable structural characteristics,which make them have good application prospects in organic semiconductor devices.Its potential application value as an organic photoelectric material has attracted great attention.As an important class of PAHs,hexabenzopyrene has great research value.Hexabenzopyrene has two different types of planes and surfaces.Compared with planar hexabenzopyrene,the aromatic nucleus of twisted hexabenzopyrene(c-HBC)and its derivatives is distorted and has strong self-assembly properties.C-HBC forms a hexagonal ordered columnar liquid crystal phase.The laminated coaxial aromatic core can act as a channel for the charge and the exterior of the molecule can behave as an insulating sheath.At the same time,this non-planar structure can produce a good agreement for substances with a convex structure such as fullerenes,which provides a way for the separation and purification of fullerenes.The surface hexabenzopyrene(c-HBC)is the main research content of our laboratory.It is very meaningful to study and synthesize nanobelts based on HBC.In this thesis,a series of novel organic conjugated fused aromatic hydrocarbon materials were designed and synthesized,and the relationship between structure and properties was studied.The details are as follows:(1)A thiophene-modified HBC dimer was designed and synthesized.The design idea of this molecule is to introduce heteroatoms on the basis of HBC dimers in order to adjust the dihedral angle and band gap width of the twisted fused aromatic hydrocarbons by doping with heteroatoms.In view of its solubility,a thiophene-modified HBC dimer having a carbon-dodecaneoxy chain is preferentially synthesized.Subsequently,in order to obtain the crystal structure of the thiophene-modified HBC dimer,we continued the exploration of synthesizing the chain-free thiophene-modified HBC dimer.(2)Design and synthesis of X-type HBC molecules.The molecular design method is based on the HBC as the basic unit,starting from the core HBC molecular unit,and then using Suzuki coupling in the direction of the upper,lower,left and right corners,and then attaching an HBC molecular unit,and then An X-type molecule is formed by photocyclization.The purpose of our design of this molecule is to obtain a fused aromatic hydrocarbon with a larger area of conjugation.However,due to the large volume of the HBC basic unit and the large steric hindrance,X-type HBC molecules have not yet been synthesized.