Study On Preparation,Photophysical Properties And Electroluminescence Properties Of Pyrene Arene Molecules

Construction of novel polyacenes and in vestigating their photoelectronic properties have become hot topic for scientists.Generally,with the increase of the number of benzene rings,polyacene usually encounter multistep synthesis,tedious separation,easy oxidation and poor solubility in organic solvents.Thus,the introduction of substitute and cyclopenta rings to the parent acene skeleton can enhance the stability and solubility,but also tune the physical properties to a great extent.Therefore,the preparation of novel acene molecules is a big challenge for the synthetic researchers.Herein,this thesis focuses on this research hotspot,we synthesize a family of functionalized arenes and examine their photophysical behavior,chemical oxidation and potential application in organic devices.This thesis is mainly divided into the following sections:(1)Two novel cyclopenta ring-modified arenes(DPCF and DPyF)containing eleven aromatic ring linearly fused together and their derivatives(16,17,18)have been synthesized and characterized by nuclear magnetic resonance(NMR),mass spectrometry and infrared spectroscopy.Subsequently,the optical and electrical properties of the as-formed compounds were measured using UV-visible,fluorescence and cyclic voltammetry.Their optical stability was tested according to changes in the ultraviolet-visible absorption spectrum,suggesting that DPCF had slightly worse stability than other molecules.Silver hexafluoroantimonate was added to the methylene chloride solution of DPCF and DPyF,and the color of the solution changed from green to brown.Meanhwile the ultraviolet absorption spectrum was significantly red-shifted,accompanied by the generation of ESR signals,indicating the presence of free radicals.Upon further addition of silver hexafluoroantimonate,the absorption spectra blue shifted and the ESR signals disappeared,meaning the formation of positively charged derivatives.In addition,the results were verified by theoretical calculations.(2)It is extremely challenging to approach twistacene including elecven all carbon six-membered rings annulated linearly.Following this direction,the end-capping undecene with pyrene untis have designed and synthesized.By using multi-step Diels-alder cycloaddition reaction,the precursor molecule containing two carbonyl groups was obtained,which wad characterizd through NMR and mass spectrometry.In addition,further modification and characterization are on the way.(3)In this work,three novel pyrene derivatives 1-3 containing bis(4-(tert-butyl)phenyl)amine as the electron donor have been synthesized and characterized by nuclear magnetic resonance,mass spectrometry and infrared spectroscopy.The optical and electrical properties of the molecules were tested using ultraviolet-visible,fluorescent spectra and cyclic voltammetry method.In addition,these molecules exhibited excellent photothermal stability.The OLEDs were fabricated by using these compounds as emitters,which could emit strong cyan,green and red electroluminescence.This study can enrich the derivation of pyrene and lay the experimental foundation for constructing electroluminescent devices with excellent performance.