A R T I C L E S
Arai et al.
The reaction was quenched by the addition of water. The reaction
product was extracted with diethyl ether, and the organic layer was
washed with brine, dried over MgSO4, filtered, and evaporated. The
crude product was purified by silica gel column chromatography
(dichloromethane) to yield 6 (1.20 g, 61%) as a yellow powder.
1H NMR (CDCl3, TMS, 400 MHz) δ 0.89 (t, J ) 7 Hz, 3 H),
1.25-1.50 (m, 10 H), 1.79 (quintet, J ) 7 Hz, 2 H), 1.93 (s, 3 H),
1.97 (s, 3 H), 3.75 (t, J ) 7 Hz, 2 H), 4.05-4.15 (m, 4 H), 5.85 (s,
1 H), 6.90 (d, J ) 9 Hz, 2 H), 7.14 (s, 1H), 7.29 (s, 1 H), 7.44 (d,
J ) 9 Hz, 2 H), 7.49 (d, J ) 8 Hz, 2 H), 7.55 (d, J ) 8 Hz, 2 H);
FAB HRMS (m/z) [M]+ Calcd for C38H38F6O3S2: 720.2167, Found:
720.2160.
(10-250 mm), eluent: hexane/AcOEt ) 95:5, flow: 3 mL/min,
retention time: 1a ) 30 min; 1b ) 26 min). UV-vis (AcOEt) λmax
(ε) 606 (2.0 × 104) nm.
2-[4-(4-{3,3,4,4,5,5-Hexafluoro-2-[5-(4-methoxymethoxy-phen-
yl)-2-methyl-thiophen-3-yl]-cyclopent-1-enyl}-5-methyl-thiophen-
2-yl)-phenyl]-[1,3]dioxolane (11). To a solution of 2,4-dibromo-
5-methylthiophene (3)19 (2.9 g, 11.4 mmol) in dry THF (40 mL)
was slowly added n-butyllithium hexane solution (1.6 M, 9.7 mL,
15.5 mmol) at -78 °C under an argon atmosphere. The solution
was stirred for 30 min at -78 °C. After the addition of trin-butyl
borate (6 mL, 15.6 mmol), the reaction mixture was further stirred
for 1 h at -78 °C. The reaction was quenched by the addition of
water. 1-Bromo-4-methoxymethoxy-benzene (3.0 g, 11.4 mmol),
Pd(PPh3)4 (200 mg, 0.17 mmol), and aqueous Na2CO3 (20 wt %,
30 mL) were added to the solution. The solution was refluxed
overnight. The reaction product was extracted with diethyl ether,
and the organic layer was washed with brine, dried over MgSO4,
filtered, and evaporated. The crude product was purified by silica
gel column chromatography (chloroform:hexane ) 1:2) to yield
4-(4-{3,3,4,4,5,5-Hexafluoro-2-[2-methyl-5-(4-octyloxy-
phenyl)-thiophen-3-yl]-cyclopent-1-enyl}-5-methyl-thiophen-2-yl)-
benzaldehyde (7). To a solution of compound 6 (600 mg, 0.83
mmol) in wet acetone (50 mL) was added pyridinium p-toluene-
sulfonate (500 mg, 2.00 mmol) at room temperature. The solution
was refluxed overnight. After cooling, the reaction mixture was
poured into water and extracted with diethyl ether, and the organic
layer was washed with brine, dried over MgSO4, filtered, and
evaporated. The crude product was purified by silica gel column
chromatography (hexane/dichloromethane ) 4:6) to yield 7 (450
1
bromothiophene derivative 9 (2.8 g, 79%) as a white powder. H
NMR (CDCl3, TMS, 400 MHz) δ 2.40 (s, 3 H), 3.48 (s, 3 H), 5.19
(s, 2 H), 6.99 (s, 1 H), 70.04 (d, J ) 9 Hz, 2 H), 7.42 (d, J ) 9 Hz,
2 H); EI MS (m/z) [M]+ 312, 314.
1
mg, 77%) as a yellow amorphous. H NMR (CDCl3, TMS, 400
MHz) δ 0.89 (t, J ) 7 Hz, 3 H), 1.28-1.43 (m, 10 H), 1.76 (quintet,
J ) 7 Hz, 2 H), 2,39 (s, 3 H), 3.96 (t, J ) 7 Hz, 2 H), 6.85 (d, J
) 9 Hz, 2 H), 7.14 (s, 1 H), 7.29 (s, 1 H), 7.43 (d, J ) 9 Hz, 2 H),
7.46 (d, J ) 8 Hz, 2 H), 7.54 (d, J ) 8 Hz, 2 H); FAB HRMS
(m/z) [M]+ Calcd for C36H34F6O2S2: 676.1904, Found: 676.1907.
4-(4-{3,3,4,4,5,5-Hexafluoro-2-[2-methyl-5-(4-octyloxy-phen-
yl)-thiophen-3-yl]-cyclopent-1-enyl}-5-methyl-thiophen-2-yl)ben-
zoic Acid (8). Jones reagent, which was prepared from CrO3 (43
mg, 0.43 mmol), H2SO4 (0.03 mL), and H2O (1 mL) was added
dropwise to a stirred solution of 7 (450 mg, 0.66 mmol) in acetone
(70 mL) at room temperature and further stirred for overnight. The
reaction mixture was extracted with diethyl ether and the organic
layer was washed with brine, dried over MgSO4, filtered, and
evaporated. The crude product was purified by silica gel column
chromatography (dichloromethane) to yield 8 (450 mg, 77.0%) as
a green powder. 1H NMR (CDCl3, TMS, 400 MHz) δ 0.90 (t, J )
6 Hz, 3 H), 1.28-1.43 (m, 10 H), 1.79 (quintet, J ) 8 Hz, 2 H),
1.95 (s, 3 H), 1.99 (s, 3 H), 3.97 (t, J ) 6 Hz, 2 H), 6.90 (d, J )
9 Hz, 2 H), 7.15 (s, 1 H), 7.41 (s, 1 H), 7.44 (d, J ) 9 Hz, 2 H),
7.63 (d, J ) 8 Hz, 2 H), 8.09 (d, J ) 8 Hz, 2 H); FAB HRMS
(m/z) [M]+ Calcd for C36H34F6O3S2: 692.1854, Found: 692.1844.
4-(4-{3,3,4,4,5,5-Hexafluoro-2-[2-methyl-5-(4-octyloxy-phen-
yl)-thiophen-3-yl]-cyclopent-1-enyl}-5-methyl-thiophen-2-yl)ben-
zoic Acid 4-Pyren-1-yl-butyl Ester (1a). To a solution of 8 (250
mg, 0.35 mmol) in dry DMF (4 mL), DCC (141 mg, 0.46 mmol),
DMAP (55 mg, 0.46 mmol) and 1-pyrenebutanol (130 mg, 0.46
mmol) was added at room temperature. The solution was stirred
for 7 h. The reaction was quenched by the addition of 2-propanol.
The reaction product was extracted with ethyl acetate, and the
organic layer was washed with brine, dried over MgSO4, filtered,
and evaporated. The crude product was purified by silica gel column
chromatography (dichloromethane) to yield 1 (80 mg, 24%) as a
yellow powder. 1H NMR (CDCl3, TMS, 400 MHz) δ 0.90 (t, J )
5.6 Hz, 3 H), 1.28-1.43 (m, 10 H), 1.79 (quintet, J ) 8 Hz, 2 H),
1.94-2.06 (m, 10 H), 3.44 (t, J ) 7 Hz, 2 H), 3.97 (t, J ) 6 Hz,
2 H), 4.40 (t, J ) 6 Hz, 2 H), 6.89 (d, J ) 9 Hz, 2 H), 7.15 (s, 1
H), 7.36 (s, 1 H), 7.44 (d, J ) 9 Hz, 2 H), 7.52 (d, J ) 8 Hz, 2 H),
7.89 (d, J ) 8 Hz, 1 H), 7.94 (d, J ) 8 Hz, 2 H), 7.99-8.17 (m,
7 H), 8.28 (d, J ) 9 Hz, 2 H); UV-vis (AcOEt) λmax (ε) 276 (7.1
× 104) nm; FAB HRMS (m/z) [M]+ Calcd for C56H50F6O3S2:
948.3106, Found: 948.3129.
To a solution of compound 9 (5.0 g, 16 mmol) in dry THF (250
mL) was slowly added n-butyllithium hexane solution (1.6 M, 11.2
mL, 1.8 mmol) at -78 °C under an argon atmosphere. The solution
was stirred for 1 h at -78 °C. After the addition of perfluoro-
cyclopentene (8.0 mL, 56 mmol), the reaction mixture was further
stirred for 1 h at -78 °C. The reaction was quenched by the addition
of water. The reaction product was extracted with diethyl ether,
and the organic layer was washed with brine, dried over MgSO4,
filtered, and evaporated. The crude product was purified by silica
gel column chromatography (hexane/dichloromethane ) 1:1) to
yield compound 10 (5.3 g, 77%) as a white powder. 1H NMR
(CDCl3, TMS, 400 MHz) δ 2.46 (d, J ) 3 Hz, 3 H), 3.49 (s, 3 H),
5.19 (s, 2H), 7.00 (s, 1 H), 7.03 (d, J ) 9 Hz, 2 H) 7.42 (d, J ) 9
Hz, 2 H); EI MS (m/z) [M]+ 426.
To a solution of 3-bromo-5-(4-(2,5-dioxolanyl)phenyl)-2-meth-
ylthiophene (1.3 g, 3.95 mmol) in dry THF (80 mL) was slowly
added n-butyllithium hexane solution (1.6 M, 2.7 mL, 4.3 mmol)
at -78 °C under an argon atmosphere. The solution was stirred
for 1 h at -78 °C. After the addition of compound 10 (2.1 g, 5.0
mmol) in dry THF (30 mL), the reaction mixture was further stirred
for 1 h at -78 °C. The reaction was quenched by the addition of
water. The reaction product was extracted with diethyl ether, and
the organic layer was washed with brine, dried over MgSO4, filtered,
and evaporated. The crude product was purified by silica gel column
chromatography (dichloromethane) to yield compound 11 (2.3 g,
89%) as a light green powder. 1H NMR (CDCl3, TMS, 400 MHz)
δ 1.94 (s, 3 H), 1.97 (s, 3 H), 3.48 (s, 3 H), 4.05-4.15 (m, 4 H),
5.20 (s, 2 H), 5.83 (s, 1 H), 7.05 (d, J ) 9 Hz, 2 H), 7.16 (s, 1 H),
7.28 (s, 1 H), 7.45 (d, J ) 9 Hz, 2 H), 7.49 (d, J ) 8 Hz, 2 H),
7.55 (d, J ) 8 Hz, 2 H); FAB HRMS (m/z) [M]+ Calcd for
C32H26F6O4S2:652.1177, Found: 652.1190.
4-(4-{2-[5-(4-Dodecyloxy-phenyl)-2-methyl-thiophen-3-yl]-
3,3,4,4,5,5-hexafluoro-cyclopent-1-enyl}-5-methyl-thiophen-2-
yl)benzaldehyde (13). To a solution of compound 11 (0.5 g, 0.77
mmol) in dry THF (40 mL) was slowly added HCl aq. (35%, 5
mL) at room temperature. The solution was stirred overnight at
room temperature. The reaction product was extracted with diethyl
ether, and the organic layer was washed with brine, dried over
MgSO4, filtered, and evaporated to give compound 12. The crude
product was not further purified and used in the next reaction.
To a solution of compound 12 (0.5 g, 0.88 mmol) in ethanol
(10 mL) was added KOH (50 mg, 0.89 mmol), KI (1 mg, cat.) and
1-bromododecane (2 g, 8.9 mmol) at room temperature. The
solution was refluxed overnight. The reaction product was extracted
with diethyl ether, and the organic layer was washed with brine,
dried over MgSO4, filtered, and evaporated. The crude product was
Corresponding closed-ring isomer 1b. After irradiation with UV
light, the mixture was separated by HPLC (column: Wakosil 5SIL
(21) Yamamoto, S.; Matsuda, K.; Irie, M. Chem. Eur. J. 2003, 9, 4878–
4886.
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9378 J. AM. CHEM. SOC. VOL. 130, NO. 29, 2008