The Synthesis,Characterization Of Novel N-fused Heterocyclic Rings And Application In F-sensing

N-heterocyclic compounds are major interest because of their applications in organic electronics.N-heteroacenes can be electron transporting counterparts of acenes.Theoretical investigation has indicated that introduction of nitrogen atoms into acenes leads to high electron affnities which is one of the necessary properties for n-type semiconductors.With the promise of electron transporting characteristics,N-heteroacenes have become a hot spot in materials research.Besides,the chemosensors based on N-heteroacenes as core structures are very limited,particularly in detecting F~-.In our effort to prepare new anthraquinone derivatives,we are especially interested in designing new anthraquinones substituted with triisopropylsilyl(TIPS)ethynyl groups,as such polycyclic aromatic hydro-carbons bearing TIPS groups can act as highly efficient and selective chemosensors for ion detection.Firstly,we report the synthesis of two soluble and stable diazapentacene derivatives and investigate the relationship between their structures and their properties.Secondly,two new azaacenequinone derivatives were prepared by cyclocondensation of diamines with bis(triisopropylsilyl)-dialkynyl-l,2-dione,and further reactions of the derivatives with malononitrile using Lehnert reagent afforded corresponding TCNQ derivatives.The TCNQ derivatives were characterized crystallographically by single crystal X-ray diffraction techniques,and they were also studied electrochemically and photochemically to compare with DFT calculations.Thirdly,we present the synthesis and characterization of two effective fluoride ion probes and their selective F~-sensing by naked-eye visualization.Though our study,the two diazapentacene derivatives can be synthesized effciently and are adequately stable for further investigation as active materials in organic semiconductors.Theoretical calculations and experimental investigations indicate that the two TCNQ derivatives have a significant intramolecular charge transfer(ICT)nature and high electron-accepting properties.The two heteropolycyclic structures are sensitive and selective probes for the detection of F~-with significant color changes.The detection by naked eye visualization is rapid and facile.