3226 Shin et al.
Macromolecules, Vol. 36, No. 9, 2003
was refluxed. One drop of HCl (35 wt %) was added, and the
reaction mixture was refluxed for 1 h. The reaction mixture
was cooled by room temperature, and the precipitate was
filtered and washed with methanol several times, and the solid
was dried in a vacuum oven. The product yield was 13 g (59%);
mp 227 °C. FT-IR (KBr pellet, cm-1): 3057, 2959, 2902, 2867,
1474, 1462, 1441, 1401, 1361, 1252, 1230, 1252, 1058, 964, 810,
765. 1H NMR (CDCl3): δ 6.6-8.8 (m, 13H, aromatic C-H),
1.2 (s, 18H, -CH3).
magnesium sulfate. After the solvent was distilled off under
reduced pressure with a rotary evaporator, a viscose oil was
obtained. The 1,4-dimethyl-2-(2′-ethylhexyloxy)-5-(2′′-((2′′′,7′′′-
di-tert-butyl)-9′′,9′′′-spirobifluorenyl))benzene (5) was purified
by column chromatography (silica gel, with n-hexane as an
eluent). The yield was 10.6 g (16 mmol, 80%); mp 85.2 °C. FT-
IR (KBr pellet, cm-1): 3063, 2958, 2924, 2866, 1611,1579, 1510,
1476, 1461, 1413, 1362, 1318, 1252, 1238, 1218, 1160, 1124,
1
1040, 1003, 882, 820, 771, 738, 616, 570. H NMR (CDCl3): δ
2-(2′-Eth ylh exyloxy)-p-xylen e (2). In a 1 L four-neck
round-bottom flask fitted with a dropping funnel, a low-
temperature condenser, a gas outlet, and a magnetic stirrer
bar, 70 g (573 mmol) of 2,5-dimethylphenol, 115 g (600 mmol)
of 1-bromo-2-ethylhexane, 39.5 g of KOH (85% content purity,
600 mmol), and 6 g (40 mmol) of sodium iodide were dissolved
in 620 mL of dry ethanol and heated to reflux for 64 h with
magnetic stirring. The mixture was cooled to room tempera-
ture, and then the reaction solution was decanted from the
solid formed and evaporated using a rotary evaporator. The
residual solid was taken up in with 800 mL of toluene. The
organic phases were combined, washed with 50 mL of 10%
aqueous NaOH solution, and dried over MgSO4. The solvent
was distilled off under reduced pressure with a rotary evapo-
rator. The residue was distilled under reduced pressure (0.5
mmHg, 108-110 °C). 124.7 g (532 mmol, 93%) of 2-(2-
ethylhexyloxy)-p-xylene (2) was obtained as a colorless oil; bp
108-110 °C/0.5 mmHg. FT-IR (KBr pellet, cm-1): 3047, 3023,
2958, 2901, 2872, 2864, 1615, 1586, 1509, 1461, 1414, 1379,
1309, 1265, 1158, 1130, 1039, 997, 843, 802. 1H NMR
(CDCl3): δ 6.98 (d, 1H, aromatic C-H), 6.63 (d, 2H, aromatic
C-H), 3.82 (d, 2H, -OCH2), 2.29 (s, 3H, aromatic CH3), 2.17
(s. 3H, aromatic CH3), 0.90-1.71 (m, 15H, aliphatic C-H).
2-Br om o-5-(2′-eth ylh exyloxy)-p-xylen e (3). 117 g (500
mmol) of compound 2, 350 mL of carbon tetrachloride, and 1.4
g (8.7 mmol) of iron(III) chloride were placed in a 1 L round-
bottomed flask. In an ice bath, 80 g (507 mmol) of bromide
was slowly added through the condenser. The mixture was
stirred for 8 h. After the reaction mixture was washed with
5-10% sodium hydroxide and dried with magnesium sulfate,
the solvent was distilled off by an evaporator. The crude
product was purified by distillation (128-130 °C/0.5 mmHg).
131 g (420 mmol, 84%) of 2-bromo-5-(2′-ethylhexyloxy)-p-xylene
(3) was obtained as a colorless oil; bp 128-130 °C/0.5 mmHg.
FT-IR (KBr pellet, cm-1): 3047, 2958, 2901, 2872, 2860, 1742,
1606, 1569, 1497, 1461, 1385, 1366, 1303, 1251, 1164, 1140,
960, 874, 838. 1H NMR (CDCl3): δ 7.23 (s, 1H, aromatic C-H),
6.66 (s, 1H, aromatic C-H), 3.80 (d, 2H, -OCH2), 2.33 (s, 3H,
aromatic CH3), 2.14 (s, 3H, aromatic CH3), 0.90-1.71 (m, 15H,
aliphatic C-H).
4-(2-Eth ylh exyloxy)-2,5-dim eth ylben zen e Bor on ic Acid
(4). 35 g (112 mmol) of compound 3 was added to the mixture
of magnesium powders (3.26 g, 134 mmol) and dry THF (200
mL). After the reaction mixture was refluxed for 2 h and cooled
to -70 °C, 23 g (224 mmol) of trimethyl borate was added.
The reaction mixture was stirred for 12 h at room temperature
and worked up with 500 mL of 4 M HCl aqueous solution. The
obtained crude solid product was washed with water several
times and then washed with n-hexane several times. 13 g (47
mmol, 42%) of 4-(2′-ethylhexyloxy)-2,5-dimethylbenzene bo-
ronic acid (4) was obtained as a colorless solid; mp 76.9 °C.
FT-IR (KBr pellet, cm-1): 3860-3620, 3047, 2958, 2923, 2872,
2860, 2360, 2342, 1732, 1615, 1586, 1497, 1505, 1459 1283,
1265, 1157, 1130, 1038, 1022, 997, 843, 802. 1H NMR (CD3-
OD): δ 6.95 (s, 1H, aromatic C-H), 6.61 (d, 1H, aromatic
C-H), 3.80 (d, 2H, -OCH2), 2.33 (s, 3H, aromatic-CH3), 2.14
(s, 3H, aromatic CH3), 0.90-1.71 (m, 15H, aliphatic C-H).
1,4-Dim eth yl-2-(2′-eth ylh exyloxy)-5-(2′′-((2′′′,7′′′-d i-ter t-
bu tyl)-9′′,9′′′-sp ir obiflu or en yl))ben zen e (5). All catalysts
and reaction were handled in a nitrogen atmosphere. To a
mixture of compound 4 (6 g, 21.6 mmol), compound 1 (10.2 g,
20 mmol), 50 mL of 2 M K2CO3 solution, and 70 mL of THF,
Pd(PPh3)4 (0.14 g, 0.6 mol %) was added as catalyst. After the
reaction mixture was refluxed under a nitrogen atmosphere
for 8 h, the reaction was terminated with water (50 mL). The
crude product was extracted with diethyl ether and dried with
6.56-7.86 (m, 15H, aromatic C-H), 3.79 (d, 2H, -OCH2),
0.87-1.93 (m, 39H, aliphatic C-H). 13C NMR (CDCl3) (ppm):
aromatic (C) 156.8, 150.6, 150.2, 148.5, 147.9, 142.3, 139.3,
133.2, 130.0, 126.8, 125.6, 124.3, 123.5, 121.9, 121.8, 120.4,
118.9, 113.7, aliphatic (C) 71.4, 66.3, 39.6, 34.7, 31.4, 30.6, 29.0,
24.0, 22.9, 21.2, 13.9, 11.1, 9.3.
1,4-Bis(br om om eth yl)-2-(2′-eth ylh exyloxy)-5-(2′′-((2′′′,7′′′-
d i-ter t-bu tyl)-9′′,9′′′-sp ir obiflu or en yl))ben zen e (6). 0.1 mg
of BPO and 2.4 g (13.6 mmol) of N-bromosuccinimide were
added to a solution of 4.5 g (6.8 mmol) of compound 5 in 50
mL of dry carbon tetrachloride. After the mixture was refluxed
for 8 h, the floating solid succinimide byproduct was filtered
away. The crude product was purified in n-hexane twice times
to give 1.5 g (1.8 mmol, 27%) of 1,4-bis(bromomethyl)-2-(2′-
ethylhexyloxy)-5-(2′′-((2′′′,7′′′-di-tert-butyl)-9′′,9′′′-spirobifluore-
nyl))benzene (6) as white crystals; mp 144 °C. FT-IR (KBr
pellet, cm-1): 3061, 3030, 2958, 2927, 2867, 1608, 1506, 1475,
1460, 1411, 1361, 1319, 1250, 1212, 1162, 1038, 834, 820, 771,
754, 738, 570. 1H NMR (CDCl3): δ 6.70-7.91 (m, 15H,
aromatic C-H), 4.54 (s, 2H, -CH2Br), 4.14 (s, 2H, -CH2Br),
3.88 (d, 2H, -OCH2), 0.89-1.75 (m, 33H, aliphatic C-H). 13C
NMR (CDCl3) (ppm): aromatic (C) 156.4, 150.7, 150.0, 149.7,
148.7, 141.3, 140.9, 139.2, 138.7, 136.8, 134.4, 132.2, 128.5,
127.8, 127.6, 127.5, 126.5, 125.0, 124.8, 120.5, 119.9, 119.8,
119.1, 113.2, aliphatic (C) 77.2, 77.0, 76.7, 70.4, 66.2, 39.4, 34.8,
31.6, 31.4, 30.6, 29.1, 28.2, 24.0, 23.0, 14.0, 11.2. Anal. Calcd
for C49H54Br2O: C, 71.88%; H, 6.65%. Found: C, 71.82%; H,
6.54%.
P oly(2-(2′-et h ylh exyloxy)-5-(2′′-(2′′′,7′′′-d i-ter t-b u t yl)-
9′′,9′′′-spir obiflu or en yl)-1,4-ph en ylen evin ylen e), EHSBF-
P P V (7). t-BuOK (1.0 M) in THF (3 mL) was added to a
solution containing 1,4-bis(bromomethyl)-2-(2′-ethylhexyloxy)-
5-(2′′-(2′′′,7′′′-di-tert-butyl)-9′′,9′′′-spirobifluorenyl)benzene (6)
(0.82 g, 1 mmol) in THF (20 mL). After the solution was stirred
for 10 h at room temperature and refluxed for 2 h, the mixture
was cooled to room temperature. The polymer was obtained
from precipitation in methanol (200 mL). The yield of the
polymer after complete workup was 0.55 g (83%). FT-IR (KBr
pellet, cm-1): 3061, 2958, 2927, 2868, 1596, 1502, 1476, 1461,
1412, 1362, 1326, 1252, 1214, 1170, 1127, 1039, 970, 819, 770,
737: δ 6.6-7.8 (m, 17H, aromatic and vinyl C-H), 3.6-3.7
(broad, 2H, -OCH2), 0.6-1.8 (m, 33H, aliphatic C-H). Anal.
Calcd for C49H54O: C, 89.31%; H, 8.26%. Found: C, 89.28%;
H, 8.29%.
Ch a r a cter iza tion . Melting points were determined using
1
an Electrothermal Mode 1307 digital analyzer. H NMR and
13C NMR spectral data were expressed in ppm relative to the
internal standard and were obtained on a DRX 500 MHz NMR
spectrometer. FT-IR spectra were obtained with a Bomem
Michelson series FT-IR spectrometer, and the UV-vis absorp-
tion spectra were obtained in chloroform on a Shimadzu UV-
3100 spectrophotometer. Molecular weight and polydispersity
of the polymer were determined by gel permeation chroma-
tography (GPC) analysis with polystyrene standard calibration
(Waters high-pressure GPC assembly model M590 pump,
µ-styragel columns of 105, 104, 103, 500, and 100 Å, refractive
index detectors, solvent THF). Elemental analyses were
performed by a Leco Co. CHNS-932. TGA measurements were
performed on a Perkin-Elmer series 7 analysis system under
N2 at a heating rate of 10 °C/min. The photoluminescence
spectra were recorded on a Perkin-Elmer LS-50 fluorometer
utilizing a lock-in amplifier system with a chopping frequency
of 150 Hz. For the measurements of device characteristics,
current-voltage (I-V) changes were measured using a cur-
rent/voltage source (Keithley 238) and an optical power meter
(Newport 818-SL). The thickness of films was determined with