Design,Synthesis,Functionlization And Optoelectronic Properties Of Oxazole–Fused Trichalcogensumanenes

Organic π–conjugated polycycles display intriguing optoelectronic and assembled properties,and they have become inherent building blocks for the construction of organic functional materials.Compared with the planar polycyclic aromatic hydrocarbons(PAHs)and spherical fullerenes,generous attentions have paid to bowl–shaped conjugated molecule for its unique physicochemical properties.Besides that,oxazole–fused conjugated molecule is used extensively to construct organic devices which exhibit excellent optoelectronic properties and responsive behavior.To tuning the photophysical properties of trichalcogensumanenes,we envisaged that the combination of the two in one molecule would expand π–system and generate an array of new materials compounds,which called oxazole–fused trichalogensumanenes.Moreover,oxazole–fused trithiasumanenes were further converted to a series of oxazole–fused tri(S,S–dioxides)trithiasumanenes or oxazole–fused trithiasumanene–based dimer/trimer.The optoelectronic properties and responsive behavior of these new heteropolycycles were elucidated.In chapter 1: Background and design rationale.We made a brief introduction about the structure–properties relationship of PAHs and their application.Overview the development of bowl–shaped corannulene and sumanene,including their synthesis,functionalization,properties and applications.Based on the above,the design of this thesis is proposed.In chapter 2: Design,synthesis,and crystal structure of oxazole-fused trichalcogensumanenes.Besides the trichalcogensumanenes,π–conjugated scaffold containing oxazole ring also exhibit excellent optoelectronic properties and responsive behavior.Based on the envisioning of combination of two in one,we synthesis a series of oxazole–fused trichalcogensumanenes.The crystal structure of these new compounds were described.In chapter 3: Optoelectronic properties and responsive behavior of oxazole–fused trichalcogensumanenes.Theoretical calculations and spectroscopic studies indicated that energy gaps are narrowed,which leads to the bathochromic shifts on absorption spectra and emission.These compounds display distinctive visual response towards chemical substances(acid,sulfide ions)by changing the substituents on oxazole motif,which can be applied as acid and sulfide ions sensors.This work expands the application of trichalcogensumanenes.In chapter 4: Design,synthesis,and properties of oxazole–fused tri(S,S–dioxides)trithiasumanenes.The π–systems embedded with thiophene S,S–dioxides usually exhibit strong emission and would serve as n–type semiconductors.Therefore,oxazolefused trithiasumanenes were successfully converted to their tri(S,S–dioxides)forms.Spectroscopic studies reveals that they exhibit red–shifted absorption bands and emission in compared with precursor.Moreover,these compounds display solid emission and visual response towards aniline or triethylamine,which can be applied as aniline or triethylamine chemsensors.In chapter 5: Design,synthesis,and properties of oxazole–fused trithiasumanene–based dimer/trimer.Dimer or trimer,which possessing functional units,often shows unique optical properties.The oxazole–fused trithiasumanene–based dimer and trimer were obtained via Suzuki–Miyaura coupling reaction.Theoretical calculations and spectroscopic studies suggests that the energy gaps are narrowed and it gives rise to the bathochromic shifts on absorption spectra and emission.Moreover,the oxazole–fused trithiasumanene–based dimer and trimer exhibit visual response towards acid that could act as acid sensors.In chapter 6: Summary and outlook.A brief summary the results of this thesis,along with the unsettled issues of the present work.Furthermore,we make the rational future perspectives.