8982 Xu et al.
Macromolecules, Vol. 37, No. 24, 2004
room temperature. After stirred for 5 min, the reaction mixture
was quenched with a THF solution of iodine (11.3 g, 44.5
mmol). A saturated Na2S2O3 aqueous solution was then added,
and the mixture was extracted with ether. The organic layer
was washed with brine, dried over MgSO4, filtered, and
concentrated under reduced pressure. The mixture was puri-
fied by a silica gel column chromatography with hexane (Rf )
0.15) as an eluent to give 5.89 g (9.30 mmol) of 2a in 84% yield
as a pale yellow viscous oil: 1H NMR (300 MHz, CDCl3): δ
0.78 (t, J ) 6.6 Hz, 12H), 0.86-1.02 (m, 8H), 1.12-1.32 (m,
32H), 3.84 (s, 6H), 6.72 (dd, J ) 2.1, 7.8 Hz, 2H), 6.84 (d, J )
2.1 Hz, 2H), 7.43 (d, J ) 7.8 Hz, 2H). 13C NMR (67.8 MHz,
CDCl3): δ 12.71, 14.14, 22.65, 24.15, 31.48, 33.10, 55.13,
110.16, 112.35, 129.85, 133.31, 152.28, 161.30, 165.04. 29Si
NMR (53.5 MHz, CDCl3): δ 2.46. Anal. Calcd for C40H74O2Si2:
C, 75.88; H, 10.19. Found: C, 75.61; H, 10.53.
3,8-Dimethoxyl-5,5,10,10-tetramethyl-5,10-dihydro-5,10-
disilaindeno[2,1-a]indene (2b). This compound was pre-
pared essentially in the same manner as described for 2a in
72% yield as colorless crystals: mp 215-217 °C. 1H NMR (300
MHz, CDCl3): δ 0.43 (s, 12H), 3.84 (s, 6H), 6.74 (dd, J ) 2.4,
7.8 Hz, 2H), 6.85 (d, J ) 2.4 Hz, 2H), 7.47 (d, J ) 7.8 Hz, 2H).
13C NMR (67.8 MHz, CDCl3): δ -3.14, 55.25, 110.21, 112.28,
131.19, 132.98, 151.30, 161.46, 164.79. 29Si NMR (53.5 MHz,
CDCl3): δ -1.78. Anal. Calcd for C20H24O2Si2: C, 68.13; H,
6.86. Found: C, 67.97; H, 6.86.
-78 °C. After stirring for 8 h at -78 to -50 °C, 2-isopropoxy-
4,4,5,5-tetramethyl-1,3,2-dioxaborolane (2.64 g, 14.2 mmol)
was added at -78 °C, and the mixture was allowed to warm
to room temperature over 12 h with stirring. The mixture was
poured into water and extracted with diethyl ether. The
organic layer was washed with brine, dried over MgSO4,
filtered, and concentrated under reduced pressure. The result-
ing mixture was passed through a short silica gel column with
a 1/1 hexane/chloroform mixed solvent as an eluent, followed
by the further purification by a preparative GPC (toluene) to
give 0.81 g (0.91 mmol) of 6a in 29% yield as a pale yellow
solid: mp 160-162 °C. 1H NMR (300 MHz, CDCl3): δ 0.78 (t,
J ) 6.6 Hz, 12H), 0.90-1.00 (m, 8H), 1.10-1.42 (m, 32H), 3.87
(s, 6H), 6.81 (s, 2H), 7.80 (s, 2H). 13C NMR (67.8 MHz,
CDCl3): δ 12.78, 14.17, 22.63, 24.20, 24.92, 31.50, 33.13, 55.67,
83.19, 108.43, 128.62, 140.47, 155.48, 166.55, 166.63. 29Si NMR
(53.5 MHz, CDCl3): δ 2.78. HRMS (FAB): Calcd for C52H86B2O6-
Si2: 884.6149. Found: 884.6167.
3,8-Difluoro-5,5,10,10-tetrahexyl-2,7-diiodo-5,10-dihy-
dro-5,10-disilaindeno[2,1-a]indene (7a). To a THF (17.5
mL) solution of 2,2,6,6-tetramethylpiperidine (609 µL, 3.61
mmol) was added a hexane solution of n-BuLi (1.56 M, 2.1 mL,
3.28 mmol) at -78 °C. The mixture was stirred at 0 °C for 30
min. A THF (7.5 mL) solution of di-tert-butylzinc, prepared
from ZnCl2(tmeda) (995 mg, 3.94 mmol) and t-BuLi (1.45 M,
5.4 mL, 7.88 mmol), was added to the mixture at -78 °C,
followed by stirring at 0 °C for 30 min. After warming to room
temperature, a THF (7.5 mL) solution of 3a (500 mg, 0.82
mmol) was added, and the reaction mixture was stirred at
room temperature for 3 h. A THF (8.5 mL) solution of iodine
(2.32 g, 9.14 mmol) was then added at -78 °C. The resulting
mixture was gradually warmed to room temperature with
stirring for 17 h. A saturated Na2S2O3 aqueous solution was
added, and the mixture was extracted with ether. The organic
layer was washed with brine, dried over MgSO4, filtered, and
concentrated under reduced pressure. The mixture was puri-
fied by a silica gel column chromatography with hexane as an
eluent (Rf ) 0.75) to give 607 mg (0.71 mmol) of 7a in 86%
yield as pale yellow crystals: mp 92-94 °C. 1H NMR (270
MHz, CDCl3): δ 0.80 (t, J ) 6.6 Hz, 12H), 0.89-1.05 (m, 8H),
1.16-1.23 (m, 32H), 6.94 (d, J ) 8.9 Hz, 2H), 7.82 (d, J ) 6.9
Hz, 2H). 13C NMR (67.8 MHz, CDCl3): δ 12.0, 14.0, 22.5, 23.8,
3,8-Difluoro-5,5,10,10-tetrahexyl-5,10-dihydro-5,10-
disilaindeno[2,1-a]indene (3a). This compound was pre-
pared essentially in the same manner as described for 2a in
1
60% yield as colorless crystals: mp 67-68 °C. H NMR (270
MHz, CDCl3): δ 0.79 (t, J ) 6.6 Hz, 12H), 0.86-1.06 (m, 8H),
1.16-1.29 (m, 32H), 6.89 (ddd, J ) 2.3, 7.9, 9.6 Hz, 2H), 6.95
(dd, J ) 2.3, 9.9 Hz, 2H), 7.65 (dd, J ) 6.6, 7.9 Hz, 2H). 13C
NMR (67.8 MHz, CDCl3): δ 12.2, 14.0, 22.5, 23.9, 31.3, 32.9,
2
2
112.4 (d, JCF ) 20.7 Hz), 112.7 (d, JCF ) 18.4 Hz), 133.1 (d,
3JCF ) 8.6 Hz), 134.1 (d, JCF ) 3.6 Hz), 152.6 (d, JCF ) 7.3
Hz), 164.8 (d, JCF ) 247 Hz), 165.1 (d, JCF ) 1.6 Hz). Anal.
Calcd for C38H58F2Si2: C, 74.94; H, 9.60. Found: C, 74.68; H,
9.65.
4
3
1
4
5,5,10,10-Tetrahexyl-2,7-diiodo-3,8-dimethoxy-5,10-di-
hydro-5,10-disilaindeno[2,1-a]indene (5a). To a solution
of 2a (2.02 g, 3.19 mmol) in THF (65 mL) was added a
cyclohexane/hexane solution of s-BuLi (0.97 M, 13.8 mL, 13.39
mmol) dropwise at -78 °C. After stirring for 8 h at -78 to
-50 °C, a THF (10 mL) solution of iodine (3.40 g, 13.40 mmol)
was added at -78 °C, and the mixture was allowed to warm
to room temperature over 12 h with stirring. A saturated
Na2S2O3 aqueous solution was added, and the mixture was
extracted with CHCl3. The organic layer was washed with
water and brine, dried over MgSO4, filtered, and concentrated
under reduced pressure. The mixture was passed through a
silica gel column with hexane (Rf ) 0.13) as an eluent, followed
by further purification by a preparative GPC (toluene) to give
0.88 g (1.00 mmol) of 5a in 31% yield as a pale yellow solid:
2
2
31.3, 32.8, 79.4 (d, JCF ) 25.6 Hz), 112.8 (d, JCF ) 23.2 Hz),
137.1 (d, 4JCF ) 3.7 Hz), 142.5, 152.4 (d, 3JCF ) 7.3 Hz), 163.2
(d, JCF ) 245 Hz), 164.7 (d, JCF ) 2.5 Hz). HRMS (FAB):
Calcd for C38H56F2I2Si2: 860.1978. Found: 860.1990.
1
4
3,8-Difluoro-5,5,10,10-tetrahexyl-2,7-bis(4,4,5,5-tetra-
methyl-1,3,2-dioxabororan-2-yl)-5,10-dihydro-5,10-di-
silaindeno[2,1-a]indene (8a). To a solution of 7a (516 mg,
0.60 mmol) in Et2O (30 mL) was added a hexane solution of
n-BuLi (1.39 M, 870 µL, 1.21 mmol) dropwise at -78 °C. After
stirred for 10 min, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-
dioxaborolane (980 µL, 4.80 mmol) was added at the same
temperature. After stirred for 2 h at -78 °C, the mixture was
gradually warmed to room temperature over 17 h. The
insoluble salts were removed by filtration, and the filtrate was
concentrated under reduced pressure. The mixture was puri-
fied by a recycle preparative GPC using chloroform as an
eluent to give 327 mg (0.38 mmol) of 8a in 60% yield as a white
powder: mp 168-170 °C. 1H NMR (270 MHz, CDCl3): δ 0.78
(t, 6.9 Hz, 12H), 0.86-0.98 (m, 8H), 1.13-1.27 (m, 32H), 1.38
1
mp 76-78 °C. H NMR (300 MHz, CDCl3): δ 0. 80 (t, J ) 6.6
Hz, 12H), 0.82-1.0 (m, 8H), 1.12-1.37 (m, 32H), 3.91 (s, 6H),
6.75 (s, 2H), 7.84 (s, 2H). 13C NMR (67.8 MHz, CDCl3): δ 12.54,
14.12, 22.62, 24.13, 31.45, 33.05, 56.10, 84.12, 108.81, 132.50,
142.59, 152.32, 159.41, 164.67. 29Si NMR (53.5 MHz, CDCl3):
δ 3.63. Anal. Calcd for C40H62I2O2Si2: C, 54.29; H, 7.06.
Found: C, 54.43; H, 7.11.
5,5,10,10-Tetramethyl-2,7-diiodo-3,8-dimethoxy-5,10-
dihydro-5,10-disilaindeno[2,1-a]indene (5b). This com-
pound was prepared essentially in the same manner as
described for 5a in 17% yield as a pale yellow solid: mp >
(s, 24H), 7.17 (d, J ) 7.6 Hz, 2H), 7.84 (d, J ) 6.6 Hz, 2H). 13
NMR (67.8 MHz, CDCl3): δ 12.3, 14.0, 22.5, 23.9, 24.8, 31.3,
C
2
4
32.9, 83.7, 112.4 (d, JCF ) 23.2 Hz), 133.5 (d, JCF ) 3.7 Hz),
140.4 (d, 3JCF ) 8.6 Hz), 155.9 (d, 3JCF ) 8.5 Hz), 166.8, 169.7
(d, 1JCF ) 253 Hz), 179.4. HRMS (FAB): Calcd for C50H80B2F2O4-
Si2: 860.5749. Found: 860.5765.
1
300 °C. H NMR (300 MHz, CDCl3): δ 0.44 (s, 12H), 3.92 (s,
6H), 6.72 (s, 2H), 7.89 (s, 2H). 13C NMR (67.8 MHz, CDCl3): δ
-3.24, 56.18, 84.39, 108.30, 133.70, 142.39, 151.31, 159.59,
164.34. 13Si NMR (53.5 MHz, CDCl3): δ -0.78. HRMS (EI):
Calcd for C20H22I2O2Si2: 603.9248. Found: 603.9267.
Polymer 9. A mixture of 5a (52 mg, 59 µmol), 6a (52 mg,
59 µmol), Pd(dba)2 (0.7 mg, 1.2 µmol), PPh3 (1.5 mg, 5.7 µmol),
and Cs2CO3 (80 mg, 250 µmol) in 1.5 mL of dioxane was stirred
at 90 °C for 48 h. After addition of water, the reaction mixture
was extracted with CHCl3. The organic layer was washed with
brine, dried over MgSO4, and filtered. After concentrated under
reduced pressure, the mixture was dissolved into a small
amount of CHCl3 and poured into a vigorously stirred MeOH
5,5,10,10-Tetrahexyl-3,8-dimethoxy-2,7-bis(4,4,5,5-
tetramethyl-1,3,2-dioxabororan-2-yl)-5,10-dihydro-5,10-
disilaindeno[2,1-a]indene (6a). To a solution of 2a (1.99 g,
3.14 mmol) in THF (60 mL) was added a cyclohexane/hexane
solution of s-BuLi (0.97 M, 13.6 mL, 13.19 mmol) dropwise at