Synthesis And Characterization Of1,4-diarylfluorenes And Aza-fused Aromatic Compounds

Organic Light-emitting Diodes (OLEDs) have attracted numerous attention in recent years. Small organic molecules and polymer-based organic light-emitting materials have play key roles for organic light-emitting diodes. Fluorene and its derivatives have been widely used in OLEDs materials due to their excellent optical performance. The context of this dissertation is composed of three types of compounds including1,4-diarylfluorenes, indeno-5,12-diaza-dibenzo[a, h]anthracenes and indeno [1,2-f] isoindole diketone derivatives.The first part is about the synthesis of novel1,4-diarylfluorenones and1,4-diaryl fluorenes. Initially, arylacetic acids are dehydrated/decarboxylated in the presence of DCC/DMAP in DMF to afford various1,3-diarylacetones, which are converted into1,3-diaryl-indeno[a]cyclopenta-2,8-diones by reacting with ninhydrin under basic condition (e.g. KOH). The retro-Diels-Alder reaction of1,3-diaryl-indeno[a]-cyclopenta-2,8-diones with norbonadiene is employed as a key step to construct1,4-diarylfluorenones. Finally, the sodium sulfide is used as the sole reductant to furnish the reduction of fluorenones to fluorenes.The second part is about barely reported indeno-5,12-diaza-dibenzo[a, h]anthracenes. The key intermediate,1,3-bis(2-nitropehnyl)-indeno[a]cyclopenta-2,8-dione, is obtained by the reaction of1,3-bis(2-nitrophenyl)acetone with ninhydin, which is converted into1,4-bis(2-nitrophenyl)fluorenone by method described above. The iron-mediated reduction of nitro groups is completed to obtain1,4-bis(2-amino-phenyl)fluorenone. Then acylation between1,4-bis(2-aminophenyl) fluorenone and acyl anhydride or acyl chloride is employed to form4-(2-acylaminophenyl)-indeno[1,2,3-jk]phenthanridine. Finally, the Bischler-Napieralski reaction is used to convert4-(2-acylaminophenyl)-indeno[1,2,3-jk]phenthanridine to the target molecules with P2O5/POCl3. We also describe the synthesis of the indeno [1,2-f] isoindole triones by using the Diels-Alder reaction as the key step, which are also reduced sufficiently to fused-fluorenes by Na2S.9H2O. The optical properties of partial compounds are characterized by UV-Vis fluorescent spectra.1,4-disubstituted fluorenes and Diaza-anthracene [a, h] dibenzo [d, e] indene revealed blue and yellow emission respectively, they might be used as precursors for organic emission materials.