PCCP
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without further purification for the next reaction step. H NMR 68.04, 31.84, 29.26, 26.12, 22.67, 14.12. MALDI-TOF Spectro-
(400 MHz, CDCl3,): 7.75–7.66 (m, 4H), 7.39–7.10 (m, 2H of Nph 1H scopy calculated for C96H106O4: 1322.8091; found: 1361.23
olefin), 6.22 (d, 2H olefin), 4.06 (t, 2H OCH2), 3.91 (q, 6H (M + K), 1385.7582 (M + Na + K adduct).
OCH2CH3), 1.74 (t, 2H), 1.35 (t, 21H), 1.03 (t, 3H). 13C NMR
Synthesis of 1,3,6,8-tetrakis((6-(n-octyloxy)naphthalene-2-
(100 MHz, d ppm): 158.30, 149.91, 135.58, 133.59, 130.36, 129.33, yl)ethynyl)pyrene (PY-3). 1,3,6,8-Tetraethynylpyrene (125 mg,
128.02, 127.60, 124.38, 120.00, 117.10, 107.26, 68.69, 59.23, 32.43, 0.6 mmol), 2-bromo-6-(octyloxy)naphthalene (1.117 g, 4.8 mmol,
29.99, 29.86, 26.73, 23.27, 18.91, 14.71.
8 equiv.), PdCl2(PPh3)2 (84 mg, 0.18 mmol), CuI (30 mg,
Synthesis of 1,3,6,8-tetrakis(6-(octyloxy)naphthalene-2-yl)pyrene 0.24 mmol) and PPh3 (42 mg, 0.24 mmol) were added to a
(PY-1). 1,3,6,8-Tetrabromopyrene (90 mg, 1.0 mmol), 2-octyloxy-6- Schlenk flask. The flask was evacuated and then refilled three
yl-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane)naphthalene (398 mg, times with N2. Toluene (5 mL) and triethylamine (15 mL) were
6.0 mmol, 6 equiv.), tetrakis(triphenylphosphine)Pd(0) (20 mg, added and the reaction mixture was stirred at 80 1C for 48 h.
0.10 mmol) and potassium carbonate (2 M aqueous 5 mL) were The reaction mixture was extracted with water (300 mL) and
added to a flame dried Schlenk flask and placed under vacuum for dichloromethane (300 mL) and dried over anhydrous magne-
15 min. Under argon flow, anhydrous THF (15 mL) was added sium sulphate. Removal of solvent via rotary evaporator
dropwise to the above reaction mixture. The reaction mixture was afforded a crude product; the crude product was purified by
subjected to vacuum/argon refill cycles three times and then it was column chromatography (silica gel, 2% hexane/dichloro-
heated to reflux at 85 1C with vigorous stirring for 48 h under methane as eluent). Precipitation was carried out in methanol
argon. Reaction progress was monitored by TLC. The mixture was and the brown colored solid (400 mg, 72% yield) PY-3 was
then poured into water (200 mL) and extracted with dichloro- collected by vacuum filtration and dried overnight.
methane (250 mL). The organic layer was washed with water
1H NMR (400 MHz, CDCl3): 7.92 (s, 4H, pyrene), 7.67 (s, 2H
(400 mL) and dried over anhydrous magnesium sulphate. Removal pyrene), 7.62–7.46 (m, 12H of Nph), 7.20–7.09 (m, 12H, Nph),
of solvent via rotary evaporator afforded a crude product, which 4.06 (t, 8H, 4OCH2), 1.84 (qui, 8H, 4CH2), 1.4 (t, 40H, 10CH2),
was further purified using column chromatography (silica gel, 2% 0.90 (t, 12H, 4CH3), 13C NMR (100 MHz, CDCl3): 157.07, 132.76,
ethyl acetate in hexane as eluent) to obtain PY-1 (130 mg, 61% 129.56, 129.28, 129.17, 128.07, 127.99, 119.74, 116.51, 106.13,
yield) as a green solid.
67.76, 31.49, 29.04, 28.92, 25.76, 22.34, 13.79. MALDI-TOF
1H NMR (400 MHz, CDCl3): 8.24 (s, 4H, pyrene), 8.18 (s, 2H, Spectroscopy calculated for
pyrene), 8.06 (dd, 4H, Nph), 7.88 (dd, 4H, Nph), 7.82 (dd, 8H, 1314.8032.
Nph), 7.22 (dd, 8H, Nph), 4.11 (t, 8H, 4OCH2), 1.87 (quin, 8H,
C96H98O4: 1314.7465; found:
4CH2), 1.30 (t, 40H, 10CH2), 0.88 (t, 12H, 4CH3). 13C NMR
OLED device fabrication details
(100 MHz, CDCl3): 152.52, 137.41, 136.33, 133.85, 129.66, Patterned ITO glass substrates were routinely cleaned using
129.48, 129.34, 129.48, 128.98, 128.38, 126.70, 125.54, 119.65, Decon 90 detergent and deionized water. Then, they were
106.52, 68.21, 31.94, 29.80, 29.37, 26.24, 25.01, 22.78, 4.23. blown dry by nitrogen gas and maintained in an 110 1C oven
MALDI-TOF Spectroscopy calculated for C88H98O4: 1218.7465; for 3 h before 25 min surface treatment in an ultra-violet ozone
found: 1218.8081.
(UVO3) cleaner. After the UVO3 treatment, the ITO glass sub-
Synthesis of 1,3,6,8-tetrakis((E)-2-(6-(n-octyloxy)naphthalene- strates were loaded into a vacuum deposition system with a
2-yl)vinyl)pyrene (PY-2). 1,3,6,8-Tetrabromopyrene (100 mg, base pressure of B7 ꢀ 10ꢁ7 Torr. Organic and metal layers were
1.0 mmol), (E)-triethoxy(2-(6-(octyloxy)naphthalene-2-yl)vinyl)silane sequentially deposited on the ITO glass substrates by thermal
(455 mg, 6.0 mmol, 6 equiv.), Pd(dba)2 (15 mg, 0.16 mmol), and evaporation. The device configuration is shown in Fig. 1, where
P(o-tol)3 (50 mg, 0.47 mmol) were added to a Schlenk tube. The dipyrazino[2,3-f:20,30-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile
tube was evacuated and then refilled with N2 three times. Toluene (HATCN), N,N0-bis(naphthalen-1-yl)-N,N0-bis(phenyl)-benzidine
(25 mL) was added, and the reaction mixture stirred at 80 1C for (NPB), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN)
20 min. Tetrabutyl ammonium fluoride (1.2 mL, 1.0 M in THF, doped with compound 1 or compound 2, MADN, 2,20,200-
12 equiv.) was then added, and the reaction mixture was stirred at (1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) and
80 1C for 2 days. The reaction mixture was extracted with dichloro- 4,7-diphenyl-1,10-phenanthroline doped with lithium (BPhen:Li)
methane (250 mL), washed with water (500 mL), and dried over were responsible for the hole injection layer (HIL), hole transport
anhydrous magnesium sulphate. Removal of solvent via rotary layer (HTL), emitting layer (B-EML), exciton confining layer,
evaporator afforded a crude product. The crude product was electron transport layer (ETL) and electron injection layer (EIL),
purified using column chromatography (silica gel, 2% hexane/ respectively. Compound 1 or compound 3 were doped on the
dichloromethane as eluent) to obtain PY-2 (200 mg, 75% yield) as MADN host with various dopant concentrations. After device
a yellow colored sticky solid.
fabrication, the devices were maintained at ambient condition
1H NMR (400 MHz, CDCl3): 7.74 (s, 2H, pyrene), 7.71–7.62 for electroluminescence (EL) measurement. In the EL measure-
(m, 12H, Pyrene and Nph) 7.16 (dd, 4H, Nph), 6.9 (dd, 8H, Nph), ment, the voltage–current–brightness (I–V–B) characteristics, the
5.82 (d, 4H, olefinic), 5.28 (d, 4H, olefinic), 4.07 (t, 8H, 4OCH2), CIE coordinates and the EL emission spectra were measured by a
1.86 (quin, 8H, 4CH2), 1.45 (t, 40H, 10CH2), 1.84 (t, 12H, 4CH3), Spectra PR650 CCD camera with a computer controller power
13C NMR (100 MHz, CDCl3): 157.30, 136.97, 134.36, 132.80, supply. The current and power efficiencies were calculated from
129.46, 128.82, 126.95, 126.17, 123.64, 119.27, 112.97, 106.60, the I–V–B data of the devices.
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