| A series of C-9 fluorenyl substituted anthracenes derivatives via a rigid sp3-hybridized carbon atom as blue-light-emitting materials were designed and synthesized. The influences of methyl or alkoxy at tetrahedral nature of sp3-hybridized carbon atom (at the C-9 position of fluorene moiety) and fluorine atom, phenyl, naphthyl or carbazolyl group at fluorene moiety were investigated. All the compounds were confirmed by 1H, 13C, 19F (for fluorinated commpounds) NMR and IR spectra. The photophysical properties, thermal properties, electrochemical properties of all compounds and electroluminescence properties of some compounds were investigated detailedly. The main contents are summarized below:(1) One 1-fold C-9 fluorene-functionalized anthracene compound 9-(9H-fluoren-9-yl) anthracene [FA] was synthesized through a simple method with good yield. It showed good quantum yield. The wavlength of emission peak in dichloromethane solution and solid state was located at 415 nm and 457 nm, respectively. An unoptimized device based on this compound as emittimg layer exhibited a blue light with radiance of 678 cd/m2 at 11 V and a maximum EL efficiency of 0.42 cd/A with color purity CIE x, y (0.163, 0.198).The other fluorene-functionalized anthracene compound 2,6-di-tert-butyl-9-(9H-fluoren-9-yl) anthracene was also synthesized through the same method. It showed higher thermal stability and an emission peak wavelength of 418 nm and 441nm in dilute dichloromethane solution and solid state, respectively. It was used as emitting material with the same OLED device structure, which had lower drive voltage and exhibited a blue light with radiance of 468 cd/m2 and a maximum EL efficiency of 0.41 cd/A with color purity CIE x, y (0.167,0.107). Hydrogen atom at C-9 position of 9-(9H-fluoren-9-yl) anthracene was then substituted by a methyl group to form a C-9 methylated anthracene derivative (9-(9-methyl-9H-fluoren-9-yl) anthracene). An OLED device based on this compound as emittimg layer with the same structure mentioned above exhibited a blue light with radiance of 4100 cd/m2 at 12 V and a maximum EL efficiency of 1.34 cd/A with color purity CIE x,y (0.157,0.082).(2) A series of 1-fold C-9 fluorinated-fluorene-functionalized anthracene deriva-tives, which were 9-(1-fluoro-9H-fluoren-9-yl) anthracene [1F-FA],9-(2-fluoro-9H-fluoren-9-yl) anthracene [2F-FA] and 9-(3-fluoro-9H-fluoren-9-yl) anthracene [3F-FA], respectively, were designed and synthesized to investigate the influence of fluorine atom and position of fluorine atom on the luminescence properties. Stable structure and the fluorine atom on the impact of configuration for these three compounds were determined by single crystal diffraction. Photophysical results showed that the compounds'emission peaks were located between 420nm and 450nm. The electrochemical test results showed good redox reversibility of these compounds. The hydrogen atom at C-9 position of each compound was then substituted by methyl group to form three C-9 methyl substituted compounds--9-(1-fluoro-9-methyl-9H-fluoren-9-yl) anthracene[1F-MFA],9-(2-fluoro-9-methyl-9H-fluoren-9-yl) anthracene [2F-MFA] and 9-(3-fluoro-9-methyl-9H-fluoren-9-yl) anthracene [3F-MFA]. Each of these six fluorinated compound was used as emitting layer to fabricate a simple OLED device. All devices showed deep blue emission with luminescence efficiency above 1.0 cd/A.(3) A series of 2-fold functionalized anthracene chromophores with two tetrahedral centers were designed and synthesized.They are 9,10-bis (9-methoxy-9H-fluoren-9-yl) anthracene [DMFA],2,6-di-tert-butyl-9,10-bis (9-methoxy-9H-fluoren-9-yl) anthracene [DBMFA],2,6-di-tert-butyl-9,10-bis (9-(hexyloxy)-9H-fluoren-9-yl) anthracene [DBHFA],9,10-bis (2,7-di-tert-butyl-9-(hexyloxy)-9H-fluoren-9-yl) anthracene [TBHFA]. No obvious melting points were recorded when methoxy group at C-9 position but carbonated directly. Increasing the carbon chain from methoxy to n-hexyloxy, better solubility and obvious melting points were observed. The emission peak wavelength were at about 440 nm in dilute solution and 450 nm in solid state, respectively. An unoptimized device based on these compound as emittimg layer exhibits a blue light with poor efficiency which need further improvment.(4) A series of phenyl, naphthyl or cabazolyl substitued C-9 fluorenyl-anthracene derivertives were designed, synthesized and spectraphysically determined, such as 9-(9-(anthracen-9-yl)-9H-fluoren-2-yl)-9H-carbazole [CFA],9-(9-(anthracen-9-yl)-7-phenyl-9H-fluoren-2-yl)-9H-carbazole [PCFA],9-(9-(anthracen-9-yl)-7-(naphthalen-2-yl)-9H-fluoren-2-yl)-9H-carbazole[NCFA],9,9'-(9-(anthracen-9-yl)-9H-fluorene-2, 7-diyl)bis(9H-carbazole) [DCFA].Their photophysical, thermalphysical, and electro-chemical properties were examined. These compounds showed strong photolumines-cence and had lager band gaps which indicate that these compounds are potentially good candidates or easier to doping with other materials for blue-light emitting materials in OLEDs. One compound CFA was choosen to fabricate an OLED device with the same structure as above, which showed peak wavelength at 428 nm with a weaker emission between 505 nm-550 nm. This mainly caused by the strong electron withdrawing ability of carbazolyl group. It exhibited a sky blue light with radiance of 527 cd/m2 at 12 V and a maximum EL efficiency of 1.19 cd/A with color purity CIE x, y (0.207,0.193).
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