Design, Synthesis And Theoretical Studies Of Carbazole Derivatives

Carbazole is a heterocyclic organic compound containing nitrogen atom, which is one ofthe most popular organic material that containing large conjugated system and strongintramolecular capacity. In the thesis, a variety of carbazole derivatives were synthesized bydifferent methods and then were characterized, their optical properties were studied by usingdensity functional theory methods. The contents are as follows:First,2-Amino-3-(E)-(9-p-methyl-9H-benzene carbazolyl-methylene) maleonitrile (S1)and the other three carbazole Schiff base derivatives were synthesized and characterized byx-ray diffraction, FT-IR, FT-Raman, UV-Vis,1HNMR and ESI-MS. It was found that S1belongs to the triclinic, space group is Pī. The dihedral angle between N-benzyl and carbazolering is59.7(3)°, the angle between carbazole ring and diaminomaleonitrile is only5.1(3)°. Inthe molecule S1, the hydrogen bonds are formed by the hydrogen atom of amino and thenitrogen atom of the imine group. The study of electronic absorption spectra found that themaximum absorption wavelength of S1, S2, S3, S4are396,396,325,350nm，respectively.The effect of different groups on the electron mobility of the molecules is different whichleading their electronic absorption spectra changes. Quantum chemical calculations showedthat the calculated values of B-DFT are in good agreement with the experimental values, theerror is less than3%. The electronic absorption spectra of gas phase are consistent with theexperimental values which were calculated by using TDDFT.Second, the synthesis, structure and fluorescence properties of (E)-2-(2-(9-p-benzyl-9H)-vinyl-carbazole-8-hydroxy quinoline (L1) were studied. The determination of crystalstructure found that L1belongs to the monoclinic, space group is P21/c. The dihedral anglebetween the carbazole ring and quinoline ring is only2.070(43)°. The intermolecular of L1overlap with "V" and reverse "V" unit and forming a huge reticular structure. The maximumabsorption wavelength is358nm (in DMF solvent), the maximum emission wavelength is464nm (in DMF solvent). The electron absorption and emission spectra of L1are sensitive tothe polarity of the solvents. The emission peaks in acetone and methanol solvents are473and475nm; the emission peaks in diethyl ether, ethyl acetate, dichloromethane and ethanolsolvents are located at402,387,391and387nm, respectively. Metal ions effect on theabsorption and emission spectra of L1. It is shown that Cd2+has the greatest influence,because Cd2+and L1formed the type of1:2complexes. Quantum chemical calculationsshowed that the spectra values calculated of CAM-B3LYP are in good agreement with theexperiment.Third, the carbazole derivatives that containing imidazole such as2-(9-p-tolyl-9H-carbazol-3-yl)-1H-phenanthrene-(9,10)-imidazole (C1) were synthesized andstudied. UV-Vis absorption spectra showed that the maximum absorption wavelength of C1,C2, C3were398,378and375nm, respectively. Quantum chemical calculations found thatthe other atoms of C1and C2are in the same plane except N-benzyl, the angle between thetwo phenyl of C3molecule is ca.30°. The effect of different groups on the charge mobility ofthe intramolecular is different, this leading their electronic absorption spectra and reactivity changes.The forth, the2-(N-methyl-p-phenylene)-carbazole-4,5-dinitrile-imidazole (Sa) wassynthesized and characterized by using X-ray diffraction, FT-IR and UV-Vis. A highlyefficient catalyst was found, it can catalyze diaminomaleonitrile Schiff base closed loopforming imidazole derivatives. Compared with many catalysts reported in the literature, thiscatalyst has high efficiency, with less raw material and simple conditions.