4
76 Letters in Organic Chemistry, 2009, Vol. 6, No. 6
Xu et al.
–
1
2
897.9 (C-H) cm . Anal. Calcd for C10
H
18Br
2
SSi
2
: C, 31.09,
chromatography on silica gel with petrol ether (60-90 ºC) as
H, 4.70, S, 8.30%. Found: C, 30.96; H, 4.86; S, 8.18%.
eluent to yield 1 (35 mg, 86.5%) as white powder. m.p. 82-
1
8
2
ꢀ
3 ºC. H NMR (400 MHz, CDCl
H), 7.04 (d, J = 2.8 Hz, 2H). C NMR (100 MHz, CDCl
3
) ꢀ 7.48 (d, J = 2.4 Hz,
):
142.9, 136.1, 114.0, 111.6. MS (EI, 70 ev): m/z = 195.81
1
3
3
Synthesis of 4,4ꢀ-dibromo-2,2ꢀ,5,5ꢀ-tetra(trimethylsil-
anyl)-3,3ꢀ-dithienyl sulfide (3)
+
+
(
[M] ). HRMS (TOF MS EI ) m/z (ion type, relative
+
To a solution of 2 (1.75g ,4.53 mmol) in dry ethyl ether
intensity in %, deviation for the formula): 195.9477 ([M] ,
100%, 0.9 ppm for C ). IR (KBr): 3103.1, 3089.6,
2923.7 (C-H) cm . Anal. Calcd for C : C, 48.95; H,
2.05; S, 49.00%. Found: C, 48.95; H, 2.24; S, 47.88%.
(
50 mL), n-BuLi (2.5 M in hexane, 1.8 mL, 4.5 mmol, 1
equiv) was added dropwise at -78 °C. After keeping at -78
C for 3 h, dry (PhSO S (0.71 g, 2.26 mmol, 0.5 equiv) was
added, then the reaction mixture was kept at -78 C for 1 h, -
8 4 3
H S
–
1
8
4 3
H S
°
2 2
)
o
o
5
5
C for 2.5 h and warmed up slowly to ambient
Crystal Data for (TMS)
M = 485.03, C20
P2(1)/n, a = 12.050(3) Å, b = 10.985(2) Å, c = 22.369(5) Å,
4
-1
temperature over night. The workup is same to that of
making 2. The residue was purified by column
chromatography on silica gel with petrol ether (60-90 ºC) as
eluent to yield 3 (1.28 g, 87.6%) as a white solid. From
36 3 4
H S Si , monoclinic, Space group
o
o
o
3
ꢂ = 90 , ꢃ = 102.362(4) , ꢄ = 90 , V = 2892.3(11) Å , Z = 4,
3
another reaction on the 2.72 g scale of 2, 1.97 g (86.8 %) of
Dcalcd = 1.114 g/cm . A colorless crystal of dimension 0.47 ꢀ
1
3
was obtained. m.p. 154-156 ºC. H NMR (400MHz,
0.36 ꢀ 0.22 mm was used for measurement at 296(2) K with
the ꢁ scan mode on a Bruker Smart APEX diffractometer
with CCD detector using Mo Kꢂ radiation (ꢅ = 0.71073Å).
The data were corrected for Lorentz and polarization effects
and absorption corrections were performed using SADABS
program [10]. The crystal structures were solved using the
SHELXTL program [11] and refined using full matrix least
squares. The positions of hydrogen atoms were calculated
theoretically and included in the final cycles of refinement in
a riding model along with attached carbons. The final cycle
of full matrix least-squares refinement was based on 7026
independent reflections [I >2ꢆ (I)] and 244 variable
parameters with R1 = 0.0398, wR2 = 0.1003.
1
3
CDCl
3
) ꢀ 0.432 (18H, s), 0.334 (18H, s); C NMR
) ꢀ 144.6, 140.4, 136.9, 123.1, -0.2, -1.2;
(
100MHz, CDCl
3
+
+
MS (EI, 70 ev): m/z = 642.06 ([M] ), 644.05 ([M+2] ),
+
+
6
46.05 ([M+4] ). HRMS (TOF MS EI ) m/z (ion type,
relative intensity in %, deviation for the formula): 641.9427
+
79
(
(
(
2
[M] , 42.6%, 0.9 ppm for C20
H
36 Br
2
S
3
Si
Si
Si ). IR (KBr):
954.4, 2896.4 (C-H) cm . Anal. Calcd for C20 Si
4
), 643.9393
+
79
81
[M+2] , 100%, -1.5 ppm for C20
[M+4] , 69.6%, 0.4 ppm for C20
H
36 Br BrS
3
4
), 645.9385
+
81
H
36 Br
2
S
3
4
–
1
H
36Br
2
S
3
4
:
C, 37.25; H, 5.63; S, 14.92%. Found: C, 37.27; H, 5.46; S,
4.58%.
1
Synthesis of Tetra(trimethylsilanyl)dithieno[3,4-b:3',
'-d]thiophene ((TMS) -1)
4
4
ACKNOWLEDGEMENTS
To a solution of 3 (204 mg, 0.32 mmol) in dry ethyl ether
50 ml), t-BuLi (1.5 M, 0.95 mL, 1.44 mmol, 4.5 equiv) was
added dropwise at -78 ºC. After keeping at -78 ºC for 2 h,
dry CuCl (220 mg, 1.64 mmol, 5.1 equiv) was added. The
reaction mixture was kept at -60 ºC for 2 h, then warmed up
slowly to ambient temperature over night. The workup is
same to that of making 2. The residue was purified by
column chromatography on silica gel with petrol ether (60-
The authors thank Mr. Pengtao Ma for crystal
measurement and discussion. This research was supported by
the NSFC (20572015, 20672028, 50803015), Program for
NCET-05-0610, SRF for ROCS-SEM, Program for Young
Excellent Talents in Henan Universities, Foundation of
Henan University (07YB2R006) and the Open Funding from
Key Laboratory of Photochemical Conversion and
Optoelectronic Materials, Technical Institute of Physics and
Chemistry, Chinese Academy of Sciences.
(
2
9
0 ºC) as eluent to yield (TMS)
4
-1 (130 mg, 84.7 %) as a
white solid. m.p. 90-91 ºC H NMR (400 MHz, CDCl ) ꢀ
): ꢀ
52.1, 145.4, 135.4, 129.3, 2.5, -0.7. MS (EI, 70 ev): m/z =
1
3
1
3
0
1
4
.45 (s, 18H), 0.42 (s, 18H). C NMR (100 MHz, CDCl
3
REFERENCES
+
+
84.04 ([M] ). HRMS (TOF MS EI ) m/z (ion type, relative
[1]
(a) Xiao, K.; Liu, Y.; Qi, T.; Zhang, W.; Wang, F.; Gao, J.; Qiu,
W.; Ma, Y.; Cui, G.; Chen, S.; Zhan, X.; Yu, G.; Qin, J.; Hu, W.;
Zhu, D. J. Am. Chem. Soc., 2005, 127, 13281. (b) Usta, H.; Lu, G.;
Facchetti, A.; Marks T. J. J. Am. Chem. Soc., 2006, 128, 9034. (c)
Sun, Y.; Ma, Y.; Liu, Y.; Lin, Y.; Wang, Z.; Wang, Y.; Di, C.;
Xiao, K.; Chen, X.; Qiu, W.; Zhang, B.; Yu, G.; Hu, W; Zhu, D.
Adv. Funct. Mater., 2006, 16, 426.
+
intensity in %, deviation for the formula): 484.1061 ([M] ,
00%, 1.0 ppm for C20 Si ). IR (KBr): 2954.6, 2896.7
C-H) cm . Anal. Calcd for C20 Si : C, 49.52; H, 7.48;
1
(
H
36
S
3
4
–
1
H
36
S
3
4
S, 19.82%. Found: C, 48.17; H, 7.05; S, 19.88%.
[
2]
(a) Morrison, J. J.; Murray, M. M.; Li, X. C.; Holmes, A. B.;
Morratti, S. C.; Friend, R. H.; Sirringhaus, H. Synth. Met., 1999,
Synthesis of dithieno[3,4-b:3',4'-d]thiophene (1)
1
02, 987. (b) Li, X. C.; Sirringhaus, H.; Garnier, F.; Holmes, A. B.;
4
To a solution of (TMS) -1 (100 mg, 0.21 mmol) in
Morratti, S. C.; Feeder, N.; Clegg, W.; Teat, S. J.; Friend, R. H. J.
Am. Chem. Soc., 1998, 120, 2206.
(a) Barbarella, G.; Melucci, M.; Sotgiu, G. Adv. Mater., 2005, 17,
chloroform (15 mL), TFA (0.2 mL) was added dropwise at
ambient temperature. The reaction procedure was monitored
by TLC analysis. After stirring at ambient temperature for 1
h, the reaction mixture was quenched with water (20 mL),
then extracted with chloroform (2ꢁ20 mL). The organic
[3]
1
581. (b) Mazzeo, M.; Vitale, V.; Della Sala, F.; Anni, M.;
Barbarella, G.; Favaretto, L.; Sotgiu, G.; Cingolani, R.; Gigli, G.
Adv. Mater., 2005, 17, 34. (c) Gao, J.; Li, R.; Li, L.; Meng, Q.;
Jiang, H.; Li, H.; Hu, W. Adv. Mater., 2007, 19, 3008. (d) Fong, H.
H.; Pozdin, V. A.; Amassian, A.; Malliaras, G. G.; Smilgies, D.-M.;
He, M.; Gasper, S.; Zhang, F.; Sorensen, M. J. Am. Chem. Soc.,
phase was washed with saturated NaHCO
20 mL). After drying over MgSO , the solvent was removed
in vacuo. The residue was purified by column
3
(20 mL) and brine
(
4
2
008, 130, 13202.