Synthesis And Optical Properties Of Symmetric Multi-aryl-imidazole

Aryl imidazole is relatively important class of compounds in imidazoles compounds,because it has large conjugated system, make its biological activity than the averageimidazoles compounds. However, more symmetrical aryl imidazole, not only the introductionof more aromatic substituent, but also expanded the whole compound conjugated system, thiskind of special structure, make the optical performance of this kind of imidazole derivatives isvery strong, it has better application potential.In this paper, a series of substitutive arylimidazoles with high quantum yield weresynthesised, through embellishing the molecular of1,4–bis (2,4,5-triphenyl-1H-imidazol-1-yl) benzene, such as substituent、conjugation、planarity. By changing the symmetricalsystem in the middle of the bridge bone, may be hindering the benzene ring of "release"gradually, which changed the whole conjugate length and its planarity, make its fluorescenceperformance change subsequently.We synthesized a symmetrical multi-arylimidazoles using two methods. One is thebenzil, aromatic aldehydes, aliphatic diamines with ammonium acetate or glacial acetic acid,p-phenylenediamine as a solvent in the synthesis of the molding conditionsmulti-arylimidazoles; The other is a triaryl imidazole and1,4-dibromo-butane as a rawmaterial by catalytic K2CO3, to synthesize in the DMF of the polyaromatic symmetricalimidazole. By discussing these two methods to obtain the optimal reaction conditions, and theproducts were synthesized1H NMR,13C NMR and IR spectra.UV spectrum and fluorescence spectrum were assayinged, quantum yield was calculated.The relationship of molecular structure and optic behavior was scientificly discussed. Then,we summarized the external and internal factors that influencing the optic behavior. Thereasonable analyses were given by studying mechanism.