LETTER
Studies of Various Arylene Ethynylene Fluorophores
233
(10) Double Elimination Method for 1 and 7: 1-(3,7-Di-
Table 2 Summary of lmax (nm) of emission of 2a–e
methyloctyloxy)-4-(4-ethynylphenylethynyl)benzene (1).
To a THF solution (15 mL) of 4-(3,7-dimethyloctyl-
oxy)phenylmethyl phenyl sulfone (3, 466 mg, 1.2 mmol), 4-
(trimethylsilylethynyl)benzaldehyde (4, 202 mg, 1.0 mmol)
and diethylchlorophosphate (0.17 mL, 1.2 mmol) was added
a THF solution of LiHMDS (1.0 M, 5.0 mL, 5.0 mmol) at
0 °C, and the mixture was stirred at r.t. for 16 h under argon.
After usual work-up, the organic layer was evaporated and
the residue was subjected to a column chromatography on
silica gel (10% EtOAc–hexane) to give 1-(3,7-dimethyl-
octyloxy)-4-[4-(trimethylsilylethynyl)phenyl-
b
b
Compd
2a
Solutiona (FPL
402 (0.92)
426 (0.54)
403 (0.95)
406 (0.69)
407 (0.96)
)
Powderc (FPL
440 (0.21)
490 (0.10)
430 (0.26)
452 (0.35)
446 (0.58)
)
Dl (nm)d
38
64
27
46
39
2b
2c
2d
2e
ethynyl]benzene in a pure form (358 mg, 83%). To a
solution of 1-(3,7-dimethyloctyloxy)-4-[4-(trimethylsilyl-
ethynyl)phenylethynyl]benzene (2.15 g, 5.0 mmol) in THF
(25 mL) and MeOH (25 mL) was added 6.91 g of K2CO3.
The reaction mixture was stirred for 1.5 at r.t. After H2O had
been added, the aqueous layer was extracted with EtOAc.
The combined organic layer was washed with brine, dried
over MgSO4 and filtered. The solvents were evaporated, and
the residue was subjected to column chromatography on
silica gel (20% CH2Cl2–hexane) to afford 1 in a pure form
(1.63 g, 91%).
a Fluorescence in CHCl2 (9.4·10–7 M).
b Absolute quantum yields (Hamamatsu photonics C9920-02).
c After evaporation from CH2Cl2.
d lmax(powder) – lmax(solution).
applications of these phenylene ethynylenes to organic
electronics devices. Studies along this line are in progress
in our laboratory.
Compound 1: 1H NMR (300 MHz, CDCl3): d = 0.87 (d,
J = 6.5 Hz, 6 H), 0.94 (d, J = 6.3 Hz, 3 H), 1.14–1.32 (m, 6
H), 1.48–1.64 (m, 3 H), 1.78–1.84 (m, 1 H), 3.16 (s, 1 H),
3.98–4.03 (m, 2 H), 6.87 (d, J = 8.9 Hz, 2 H), 7.43–7.46 (m,
6 H). 13C NMR (125 MHz, CDCl3): d = 19.6, 22.5, 22.6,
24.6, 27.9, 29.8, 36.0, 37.2, 39.2, 66.3, 78.6, 83.3, 87.5, 91.6,
114.5, 114.6, 121.3, 124.1, 131.2, 132.0, 133.0, 159.4.
According to the same procedure, compound 7 was prepared
from 3 and 4-iodobenzaldehyde.
Acknowledgment
This work has been supported financially by Grant-in-Aid for
Scientific Research from the Ministry of Education, Culture, Sports,
Science and Technology, Japan (MEXT).
References and Notes
Compound 7: 68%. 1H NMR (500 MHz, CDC13): d = 0.88
(d, J = 6.7 Hz, 6 H), 0.95 (d, J = 6.7 Hz, 3 H), 1.15–1.34 (m,
6 H), 1.52–1.68 (m, 3 H), 1.80–1.85 (m, 1 H), 3.99–4.03 (m,
2 H), 6.88 (d, J = 7.9 Hz, 2 H), 7.24 (d, J = 8.2 Hz, 2 H), 7.45
(d, J = 8.6 Hz, 2 H), 7.68 (d, J = 8.6 Hz, 2 H). 13C NMR (125
HMz CDC13): d = 19.6, 22.6, 22.7, 24.6, 28.0, 29.8, 36.1,
37.3, 39.2, 66.4, 87.1, 91.0, 93.6, 114.6, 114.6, 123.2, 132.9,
133.0, 137.4, 159.4.
(1) (a) Acetylene Chemistry: Chemistry, Biology, and Material
Science; Diederich, F.; Stang, P. J.; Tykwinski, R. R., Eds.;
VCH: Weinheim, 2005. (b) Modern Acetylene Chemistry;
Stang, P. J.; Diederich, F., Eds.; VCH: Weinheim, 1995.
For reviews of phenylene ethynylenes, see: (c) James, D.
K.; Tour, J. M. In Topics in Current Chemistry, Vol. 257;
Springer: Berlin, 2005, 33–62. (d) Stone, M. T.; Heemstra,
J. M.; Moore, J. S. Acc. Chem. Res. 2006, 39, 11. (e) Ray,
C. R.; Moore, J. S. Adv. Polym. Sci. 2005, 177, 91.
(2) Shirai, Y.; Osgood, A. J.; Zhao, Y.; Kelly, K. F.; Tour, J. M.
Nano Lett. 2005, 5, 2330.
(11) Typical Procedure for Sonogashira Coupling.
A 50 mL flask was charged with 7 (318 mg, 0.69 mmol), 1,4-
diethyl-2,5-diethynylbenzene (55 mg, 0.30 mmol),
Pd(PPh3)4 (34 mg, 0.03 mmol), CuI (5.0 mg, 0.03 mmol), i-
Pr2NH (1.0 mL) and toluene (20 mL), and the mixture was
heated at 65 °C for 12 h. After filtration, the filtrate was
poured into aq NH4Cl and extracted with CH2Cl2. The
combined organic layer was washed with brine, dried over
MgSO4 and filtered. After evaporation, the residue was
subjected to column chromatography to afford 2a as white
powder in a pure form (228 mg, 90%).
(3) (a) Wackerly, J. W.; Moore, J. S. Macromolecules 2006, 39,
7269. (b) Elliott, E. L.; Ray, C. R.; Kraft, S.; Atkins, J. R.;
Moore, J. S. J. Org. Chem. 2006, 71, 5282.
(c) Balakrishnan, K.; Datar, A.; Zhang, W.; Yang, X.;
Naddo, T.; Huang, J.; Zuo, J.; Yen, M.; Moore, J. S.; Zang,
L. J. Am. Chem. Soc. 2006, 128, 6576; and references
therein.
(4) Orita, A.; Jiang, L.; Tsuruta, M.; Otera, J. Chem. Lett. 2002,
136.
(5) Orita, A.; An, D.-L.; Nakano, T.; Yaruva, J.; Ma, N.; Otera,
J. Chem. Eur. J. 2002, 8, 2005.
Compound 2a: mp 151–153 °C. 1H NMR (500 MHz,
CDCl3): d = 0.87 (d, J = 6.7 Hz, 12 H), 0.94 (d, J = 6.4 Hz,
6 H), 1.15–1.20 (m, 6 H), 1.25–1.37 (m, 12 H), 1.50–1.67
(m, 6 H), 1.82–1.85 (m, 2 H), 2.85 (q, J = 7.5 Hz, 4 H), 3.99–
4.05 (m, 4 H), 6.88 (d, J = 8.8 Hz, 4 H), 7.39 (s, 2 H), 7.45–
7.49 (m, 12 H). 13C NMR (125 MHz, CDCl3): d = 14.7, 19.6,
22.6, 22.7, 24.6, 27.1, 27.9, 29.8, 36.0, 37.2, 39.2, 66.4, 88.0,
89.8, 91.5, 94.1, 114.5, 114.7, 122.4, 122.7, 123.5, 131.3,
131.4, 131.5, 133.0, 143.4, 159.3. Anal. Calcd for C62H70O2:
C, 87.90; H, 8.33. Found: C, 88.12; H, 8.60.
(6) Orita, A.; Nakano, T.; An, D.-L.; Tanikawa, K.; Wakamatsu,
K.; Otera, J. J. Am. Chem. Soc. 2004, 126, 10389.
(7) Oyamada, T.; Shao, G.; Uchiuzou, H.; Nakanotani, H.;
Orita, A.; Otera, J.; Yahiro, M.; Adachi, C. Jpn. J. Appl.
Phys. 2006, 45, 1331.
(8) A part of optical property of 4-(4-methoxyphenyl-
ethynyl)phenylethyne has been reported. See: Shao, G.;
Orita, A.; Nishijima, K.; Ishimaru, K.; Takezaki, M.;
Wakamatsu, K.; Otera, J. Chem. Lett. 2006, 35, 1284.
(9) Orita, A.; Taniguchi, H.; Otera, J. Chem. Asian J. 2006, 1,
430.
Compound 2b: mp 178–181 °C. 1H NMR (500 MHz,
CDCl3): d = 0.87 (d, J = 6.4 Hz, 12 H), 0.94 (d, J = 6.7 Hz,
6 H), 1.15–1.34 (m, 12 H), 1.50–1.69 (m, 6 H), 1.80–1.86
(m, 2 H), 3.97–4.04 (m, 4 H), 6.87 (d, J = 8.8 Hz, 4 H), 7.17
(s, 2 H), 7.45–7.48 (m, 12 H). 13C NMR (125 MHz, CDCl3):
d = 19.6, 22.6, 22.7, 24.6, 27.9, 29.8, 36.0, 37.2, 39.2, 66.4,
Synlett 2007, No. 2, 231–234 © Thieme Stuttgart · New York