Synthesis Of Carbine-copper Complexes Containing Oxazole And Thiazole Ligands And Study Of Their Optical Properties

In the study of light-emitting materials used in OLED devices,light-emitting materials are dominated by organometallic complexes such as osmium（Os）、platinum（Pt）,ruthenium（Ru）,iridium（Ir）,etc.Organometallic Cu（Ⅰ）complexes have similar optical properties to these precious metal complexes,and are gradually gaining widespread attention because of their abundant sources,low cost,easy availability,low toxicity,and environmental friendliness.The ligands of luminescent materials determine the optical properties of these precious metal complexes.Compared with traditional ligands,NHC has strongerσelectron-giving ability,increases the conjugation degree of the system,and can form stable copper complexes,thus improving the luminescence properties,therefore,NHC is a very good class of luminescent materials for the synthesis of organic luminescent transition metal complexes.In this thesis,13 copper carbene complexes containing oxazole and thiazole ligands were designed and synthesized.By introducing different groups on the oxazole and thiazole rings and side chain branched rings,the conjugation degree of the whole complexes was changed and their HOMO and LUMO energy level differences were varied,so as to achieve the modulation of the luminescence properties of the copper complexes,and their optical properties were studied and their theoretical explanations were made.Details are as follows.Firstly,2-chlorobenzoxazole was reacted with imidazole and benzimidazole to form monomers,and then with benzyl bromide containing different substituents to form the corresponding hexafluorophosphate ligands,which were reacted with bis[（2-diphenylphosphino）phenyl]ether POP and copper powder to prepare the corresponding aza-carbine-copper complexes P1,P2,P3 and P4,and their optical properties were tested.The emission wavelengths of the complexes were mainly in the range of 509-530 nm,and the phosphorescence lifetimes of P1,P2,P3 and P4were 28.7μs,25.4μs,33.1μs and 26.4μs,respectively.the quantum yields were1.8%,3.4%,4.2%and 2.1%,respectively.The TD-DFT theory was also applied to study the absorption spectra of the complexes in CH₂Cl₂and to attribute the type of leap of the complexes.Secondly,imidazole was reacted with benzothiazole containing different electronic groups（-H,-Cl,-OCH₃）to generate monomers,and with benzyl bromide to generate the corresponding hexafluorophosphate ligands,respectively,and these hexafluorophosphate ligands were reacted with bis[（2-diphenylphosphino）phenyl]ether POP,copper powder to prepare the corresponding azacyclic carbine-copper complexes P5,P6 and P7,and their optical properties were The optical properties were tested.The emission wavelengths of the complexes were mainly in the range of543-551 nm,and the overall red-shift of this series was observed compared with the first series.26.7μs,32.6μs,and 13.7μs were obtained for P5,P6,and P7,respectively.34.8%,44.1%,and 24.9%quantum yields were obtained,respectively.The TD-DFT theory was also applied to study the absorption spectra of the complexes in CH₂Cl₂and to attribute the leap types of the complexes.Finally,2-bromothiazole was reacted with imidazole and benzimidazole to form monomers,and then with benzyl bromide containing different substituents to form the corresponding hexafluorophosphate ligands,which were reacted with bis[（2-diphenylphosphino）phenyl]ether POP,copper powder to prepare the corresponding azocyclic carbine-copper complexes P8,P9,P10,P11,P12 and P13,and their optical The optical properties were tested.The emission wavelengths of the complexes were mainly in the range of 518-535 nm,and the overall blue shift of this series was observed compared with the second series.The quantum yields were13.5%,12.8%,16.7%,40.9%,33.5%,and 53.7%,respectively.The TD-DFT theory was also applied to study the absorption spectra of the complexes in CH₂Cl₂and to attribute the leap types of the complexes.