Synthesis of three kinds of star-burst carbazol derivatives and their photoelectric performances

Three kinds of star-burst carbazol derivatives,1-[(4′-N,N-diphenylamino) phenyl]-3,5-di[4-(9H′-carbazol-9′-yl)phenyl]benzene(NCBP),1,3-di[4-(9H′-carbazol-9′-yl)phenyl]-5-[(9′,9′-dimethyl)fluoren-2-yl]benzene(MCPF) and 1,3-di[4-(9H′-carbazol-9′-yl)phenyl]-5-{[7′-(9H″-carbazol-9″-yl)]-(9′,9′-dimethyl) fluoren-2-yl}benzene(MCCPF) were synthesized through methylation,the Ullmann reaction,boric acid-based reaction,and the Suzuki coupling reaction using carbazol,triarylamine and fluorene derivatives as starting materials.The structure of the target compounds was confirmed by IR,1HNMR,MS and elementary analysis.The ultra-violet and visible spectroscopy and the fluorescent spectroscopy of these compounds in dichloromethane solution were studied.The cyclic voltammetry of these compounds in N,N-dimethylformamide solution was also studied.These compounds displayed blue fluorescence.The energy levels of HOMO were-5.71 eV,-5.70 eV,and-5.69 eV,respectively.These compounds could serve as efficacious hole transport materials and main materials according to published literature.