Synthesis, Physical Property And Application Of Nitrogen-Doping Heteroacene

In recent years,the widely concerned organic light-emitting diodes?OLED?have been widely used in the field of small size display,and gradually entered the field of large area display and lighting.With the continuous development of organic luminescence technology,higher requirements have been put forward for the study of organic luminescent materials and devices.Compared with inorganic luminescent materials,organic counterparts exhibit some fascinating advantages including ease of synthesis,controllable photoelectric properties,low driving voltage and biodegradation.Oligoacenes are a kind of polycyclic aromatic hydrocarbons with large linear?-?conjugated structure that can be used as active candidates for organic electroluminescent devices and field effect transistors,organic solar cells,and nonlinear optical devices.However,this kind of molecule usually encounter some disadvantages such as poor chemical stability,and intermolecular polymerization under light and oxygen conditions.Therefore,in this thesis we aim to insert heteroatoms into the parent building blocks of acene to approach heteroacenes or heteroarenes.This strategy not only enhances the stability and antioxidation of target molecules,but also make the as-prepared molecules change from an n-type material to a p-type material.We have successfully synthesized a series of nitrogen-embedded heteroacenes,and tested their optical,electrical,and thermal properties.The substantial applications in electroluminescent devices and sensor for protons were further examined.This thesis was divided into two parts:?1?Two novel triphenylamine modified twisted acenes SNPy and DNPy were synthesized by classical Suzuki coupling reaction,which were successfully characterized by ¹H NMR,¹³C NMR and MALDI-TOF spectroscopy.SNPy and DNPy easily dissolved in common organic solvents such as methylene chloride,toluene,THF and emit bright blue fluorescence under 365nm ultraviolet light irradiation.The fluorescence quantum yields were calculated to be 0.66and 0.36,respectively.Based on TGA analysis,they showed high thermal stability.Electroluminescent devices fabricated by SNPy and DNPy displayed excellent electroluminescent properties.?2?Diazole-functionalized acenes APyS,APySe and azaacenes PyP,PyAP,PyTh,and PyPh were synthesized by classical organic condensation reactions,where their chemical structures were characterized by ¹H NMR,¹³C NMR,MALDI-TOF,elemental analysis and X-ray diffraction analysis.APyS,APySe,PyAP are formed to twisted topology configurations,while PyTh displayed a slight helical configuration.All of them emit bright yellow,orange or red fluorescence in organic solvents.TGA analysis showed that the decomposition temperatures of APyS,APySe,PyP,PyAP,PyTh,PyPh with 5%weight loss were 388?,437?,418?,445?,451?,452?,indicating good stability.The as-synthesized molecules PyP,PyAP,PyTh,and PyPh exhibited obvious spectral responses to the acid and can be used as"naked eye"probe.