Synthesis And Properties Of Pyrrole-fused Boron/nitrogen Doped Polycyclic Aromatic Hydrocarbons

In this dissertation,we mainly focus on the design and synthesis of boron and nitrogen doped polycyclic aromatic hydrocarbons.The dissertation is mainly divided into two parts.In the first part,BN-doped indole and carbazole derivatives were designed and synthesized,asystematically investigating their photophysical properties.The second part is design and synthesis of BN-doped Ullazines.We successfully synthesized a series of BN-doped Ullazines and studied their photoelectronic properties systematically.The detials are as follows:In the first part,we have successfully designed and synthesized BN-doped benzoindole 4a and BN-doped dibenzocarbazole 7aSingle crystals of 4a and 7a were obtained by solvent diffusion method.Combining their solid state structures and theoretical calculations,we concluded the azaborine sub-unit in compounds 4a and 7a have weak aromaticity.Photophysical studies of 4a and 7a a showed thier UV-visible absorption spectra and emission are quite different if different solvent.,The absorption of 4a and 7a did not change significantly by incrasing the polarity of the solvents,while their emission spectra are red shifted and the structures of the spectra are changed to structureless as well.In addition,we found that the absorption and emission spectra of 4a and 7a changed a lot upon addition of fluoride ion,which clear indicated the there is still some level of Lewis acidity of boron atom.In the second part,we designed and synthesized a series of boron/nitrogen doped Ullazine-type polycyclic aromatic hydrocarbons.We successfully constructed the BN-Ullazine in three steps from commercial available materials.Solid state structures showed the main scaffolds of PAHs are fully planar.We also did theoratical calculations on the BN-Ullzine in order to get insight to new PAHs.Again,we studied their phtophyscial properties sysmatically.We found that the substituents on the boron atom did have some influence on their absorption and emission spectra.In summary,the thesis focus on developing and photophyscial studies of novel pyrrole fused BN-doped PAHs.We hope the studies of the research in the thesis may have some implications in the fields of BN-doped organic electronic materials.