Benzo Triazole Compounds, Electronic Spectra And Structure-activity Relationship Studies

In this thesis,a relatively high level theoretical investigation has been performed using the density functional theory and time-dependent density functional theory methods to calculate the bond length,bond angles,charge distribution and frontier orbital energy, electronic spectra of a sort of benzoxazole compounds(including the benzoxazole compounds,the benzimidazole compounds and the benzothiazole compounds).First,the structures of monobromo substituted 2-propenylbenzoxazole compound have been carried out on Chem3D and then are opted by PM3 of semi-empirical methods at the level of RHF(Restricted Hartree-Fock)without any restrict of symmetry.On the base,five methods of B3LYP/3-21G,B3LYP/6-31 G,B3L YP/6-31G^*,B3LYP/6-31G^**and HF/6-31G^* are used to optimize the structures and compared with the experimental results,the results show that the method of B3LYP/6-31 G^* spent fewer time and got better data.Then,monobromo substituted benzoxazole compounds and substituted benzoxazole compounds with F,Cl,Br,NO₂,CH₃,OCH₃,N(CH₃)₂ and compounds of conjugated strctures have been studied at the B3LYP/6-31G^* level of density functional theory.The curve of the experimental fluorescent wavelengths and the state energy gap△ε,single electronic excited energy△E and dipole moment is linear.Regression equation is also got,and the predicted result is near to the experimental result.In addition,the geometry structures,electronic structures,the electronic spectrum,the intensity and the frequency of the benzoxazole compounds have been calculated and discussed.Finally,we discuss a sort of benzoxazole compounds.The curve of the experimental excited wavelengths and the state energy gap△ε,single electronic excited energy△E and dipole moment is linear.Regression equation is also got,and the predicted result is near to the experimental result.