Z. Gao et al. / Organic Electronics 15 (2014) 2667–2676
2675
A maximum gext of 3.02% and true deep blue coordinates
(0.167,0.056) are obtained in the non-doped OLED using
M2 as the emitting layer. Furthermore, some of the mate-
rials are capable of acting as effective hosts for phospho-
rescent and fluorescent guests. High performance green
phosphorescent device based on M2/Ir(ppy)3 is achieved
with a maximum gc of 33.35 cd Aꢀ1, a maximum gp of
22.99 lm Wꢀ1 and a maximum gext of 9.47%. The white
OLED using M1 as the host and an orange fluorophore
CNDPASDB as the dopant is realized with a maximum gc
of 5.53 cd Aꢀ1 and CIE coordinates of (0.313,0.305). All of
these results give us a new foreground for the design of
deep blue material design and inspire their potential appli-
cations in the future.
7.59 Hz, 1H), 7.41–7.32 (m, 5H), 7.16 (t, J = 8.37 Hz, 1H),
7.11 (d, J = 7.59 Hz, 1H); FTIR (KBr,
, cmꢀ1) 3056, 1577,
m
1496, 1453, 1382, 1234, 1175, 1141, 1107, 1039, 886,
844, 817, 755, 725, 699, 617, 570, 534; MALDI-TOF (m/z):
[M+] calcd for C60H37N5: 827.97; Found: 827.5. Anal. calcd
for C60H37N5: C 87.04, H 4.50, N 8.46; Found: C 87.30, H
4.46, N 8.28.
Synthesis of 1-phenyl-2-(9-phenyl-9H-carbazol-3-yl)-1H-
phenanthro[9,10-d]imidazole (M3): a mixture of 9-phenyl-
9H-carbazole-3-carbaldehyde (500.00 mg, 1.85 mmol),
phenanthrene-9,10-dione (460.50 mg, 2.21 mmol), aniline
(0.50 g), ammonium acetate (0.60 g, 8.00 mmol), and acetic
acid (10 mL) were refluxed under nitrogen in an oil bath.
After 2 h, the mixture was cooled and filtered. The solid
product was washed with an acetic acid/water mixture
(1:1, 150 mL) and water. It was then purified by chroma-
tography using CH2Cl2/petroleum ether (1:1) as eluent to
obtain the product as white powder. Yield: 80%. 1H NMR
(500 MHz, DMSO, d): 8.96 (d, J = 7.98 Hz, 1H), 8.91 (d,
J = 8.67 Hz, 1H), 8.76 (d, J = 7.28 Hz, 1H), 8.35 (s, 1H), 8.09
(d, J = 7.53 Hz, 1H), 7.81–7.76 (m, 4H), 7.73–7.68 (m, 6H),
7.64 (d, J = 7.08 Hz, 2H), 7.58 (t, J = 7.69 Hz, 7.08 Hz, 2H),
7.48 (t, J = 7.08 Hz, 7.00 Hz, 1H), 7.39–7.31 (m, 4H), 7.16
(d, J = 7.94 Hz, 1H); MALDI-TOF (m/z): [M+] calcd for
4. Experimental section
Synthesis of (2-(4-(9H-carbazol-9-yl)phenyl)-1-phenyl-
1H-phenanthro[9,10-d]imidazole (M1):
a
mixture of
4-(9H-carbazol-9-yl)benzaldehyde
(1.00 g,3.70 mmol),
phenanthrene-9,10-dione (767.50 mg,3.70 mmol), aniline
(0.85 g,18.50 mmol), ammonium acetate (1.14 g,
14.80 mmol), and acetic acid (10 mL) were refluxed under
nitrogen in an oil bath. After 2 h, the mixture was cooled
and filtered. The solid product was washed with an acetic
acid/water mixture (1:1,150 mL) and water. It was then
purified by chromatography using CH2Cl2/petroleum ether
(1:1) as eluent to obtain the product as white powder.
Yield: 75%. 1H NMR (500 MHz, DMSO, d): 8.96 (d, J =
8.30 Hz, 1H), 8.91 (d, J = 8.45 Hz, 1H), 8.74 (d, J = 7.36 Hz,
1H), 8.26 (d, J = 7.83 Hz, 2H), 7.89 (d, J = 8.22 Hz, 2H),
7.84–7.76 (m,6H), 7.73 (t, J = 7.50 Hz, 6.43 Hz, 1H), 7.66
(d, J = 7.94 Hz, 2H), 7.59 (t, J = 6.97 Hz, 7.68 Hz, 1H), 7.46
(t, J = 7.50 Hz, 7.14 Hz, 2H), 7.40 (d, J = 8.61 Hz, 2H), 7.38
(t, J = 7.68 Hz, 7.68 Hz, 1H), 7.32 (t, J = 7.68 Hz, 7.68 Hz,
2H), 7.11 (d, J = 8.47 Hz, 1H); 13C NMR (500 MHz, CDCl3,
Hz): 140.53, 130.80, 130.40, 130.14, 129.15, 128.39,
127.42, 126.61, 126.39, 126.02, 124.19, 123.57, 123.18,
C39H25N3:535.64; Found: 535.4. Anal. calcd for C39H25N3:
C 87.45, H 4.70, N 7.84; Found: C 87.28, H 4.66, N 7.77.
Synthesis of 2,20-(9-phenyl-9H-carbazole-3,6-diyl)bis
(1-phenyl-1H-phenanthro[9,10-d]imidazole) (M4): a mixture
of 9-phenyl-9H-carbazole-3,6-dicarbaldehyde (400.00 mg,
1.34 mmol), phenanthrene-9,10-dione (613.80 mg, 2.95
mmol), aniline (1.25 g), ammonium acetate (804.00 mg,
10.72 mmol), and acetic acid (15 mL) were refluxed under
nitrogen in an oil bath. After 2 h, the mixture was cooled
and filtered. The solid product was washed with an acetic
acid/water mixture (1:1, 150 mL) and water. It was then
purified by chromatography using CH2Cl2 as eluent to
obtain the product as white powder. Yield: 40%. 1H NMR
(500 MHz, DMSO, d): 8.97 (d, J = 8.45, 2H), 8.92 (d,
J = 8.60 Hz, 2H), 8.77 (d, J = 8.05 Hz, 2H), 8.12 (s, 2H),
7.83–7.69 (m, 18H), 7.65 (d, J = 7.74 Hz, 2H), 7.59 (t,
J = 7.74 Hz, 8.22 Hz, 3H), 7.39 (t, J = 6.89 Hz, 8.22 Hz, 4H),
7.17 (d, J = 8.10 Hz, 2H); MALDI-TOF (m/z): [M+] calcd for
120.91, 120.35, 120.20, 109.78; FTIR (KBr, m
, cmꢀ1) 3058,
1625, 1532, 1475, 1451, 1429, 1378, 1358, 1241, 1225,
1174, 1147, 1111, 1018, 1004, 929, 844, 750, 724, 667,
620, 563, 535; MALDI-TOF (m/z): [M+] calcd for C39H25N3:
535.64; Found: 535.90. Anal. calcd for C39H25N3: C 87.45,
H 4.70, N 7.84; Found: C 87.45, H 4.66, N 8.03.
Synthesis of 1-phenyl-2-(4-(3-(1-phenyl-1H-phenanthro
[9,10-d]imidazol-2-yl)-9H-carbazol-9-yl)phenyl)-1H-phenanthro
[9,10-d]imidazole (M2): a mixture of 9-(4-formylphenyl)-
C60H37N5: 827.97; Found: 828.3. Anal. calcd for C60H37N5:
C 87.04, H 4.50, N 8.46; Found: C 86.81, H 4.40, N 8.28.
Synthesis of 2-(40-(9H-carbazol-9-yl)-[1,10-biphenyl]-
4-yl)-1-phenyl-1H-phenanthro[9,10-d]imidazole (M5): 9-(4-
Bromophenyl)-9H-carbazole (354.42 mg, 1.10 mmol),
1-phenyl-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-
yl)phenyl)-1H-phenanthro[9,10-d]imidazole (496.41 mg,
1.00 mmol), K2CO3 (828.00 mg, 6.00 mmol) and tetrakis
(triphenylphosphine) palladium (11.55 mg, 0.01 mmol)
were added to a round-bottomed flask equipped with a
reflux condenser and dissolved in methylbenzene (10 mL)
and H2O (3 mL). The reaction mixture was heated at
85 °C for 24 h. The reaction mixture was then quenched
with water and extracted with chloroform. The combined
organic phases were dried (MgSO4) and concentrated
under reduced pressure. After solvent evaporation, the
liquid was purified by column chromatography using
petroleum ether/methylene chloride as eluent to afford a
white solid (460 mg). Yield: 75.0%. 1H NMR (500 MHz,
9H-carbazole-3-carbaldehyde
phenanthrene-9,10-dione
(957.30 mg,3.20 mmol),
(1.47 g,7.04 mmol), aniline
(2.98 g), ammonium acetate (1.92 g,26.30 mmol), and ace-
tic acid (10 mL) were refluxed under nitrogen in an oil
bath. After 2 h, the mixture was cooled and filtered. The
solid product was washed with an acetic acid/water mix-
ture (1:1,150 mL) and water. It was then purified by chro-
matography using CH2Cl2 as eluent to obtain the product
as white powder. Yield: 71%. 1H NMR (500 MHz, DMSO,
d): 8.97–8.94 (m, 2H), 8.92–8.89 (m, 2H), 8.76–8.74 (m,
2H), 8.35 (s, 1H), 8.08 (d, J = 8.22 Hz, 1H), 7.90 (d, J = 8.95,
2H), 7.85–7.77 (m, 10H), 7.73–7.70 (m, 5H), 7.67 (t, J =
8.37 Hz, 2H), 7.60–7.55 (m, 2H), 7.49–7.46 (t, J = 7.59 Hz,