Molecular engineering of organic dyes containing N-aryl carbazole moiety for solar cell

Article abstract of DOI:10.1016/j.tet.2006.12.082

Organic dyes containing N-aryl carbazole moiety are designed and synthesized. Under standard global AM 1.5 solar condition, the JK-25 sensitized cell gave a short circuit photocurrent density (J_sc) of 11.50 mA cm^-2, an open circuit voltage (V_oc) of 0.68 V, a fill factor of 0.66, corresponding to an overall conversion efficiency η of 5.15%, and the maximum incident monochromatic photon-to-current conversion efficiency (IPCE) of 77% at 430 nm.

Full text of DOI:10.1016/j.tet.2006.12.082

Tetrahedron 63 (2007) 1913–1922
Molecular engineering of organic dyes containing N-aryl carbazole
moiety for solar cell
*
Duckhyun Kim, Jae Kwan Lee, Sang Ook Kang and Jaejung Ko
*
Department of Chemistry, Korea University, Jochiwon, Chungnam 339-700, Republic of Korea
Received 31 October 2006; revised 22 December 2006; accepted 25 December 2006
Available online 4 January 2007
Abstract—Organic dyes containing N-aryl carbazole moiety are designed and synthesized. Under standard global AM 1.5 solar condition, the
JK-25 sensitized cell gave a short circuit photocurrent density (Jsc) of 11.50 mA cmꢀ2, an open circuit voltage (Voc) of 0.68 V, a fill factor of
0.66, corresponding to an overall conversion efficiency h of 5.15%, and the maximum incident monochromatic photon-to-current conversion
efficiency (IPCE) of 77% at 430 nm.
Ó 2006 Published by Elsevier Ltd.
1. Introduction
in organic light-emitting diodes (OLEDs) and solid-state
DSSCs.9 In this paper, we report six new organic dyes con-
taining N-(9,9-dimethylfluoren-2-yl)carbazole or N-(4-(2,2-
diphenylvinyl)phenyl)carbazole as electron donor and
cyanoacrylic acid or rhodanine-3-acetic acid as electron
acceptor bridged by thiophene or vinylene thiophene units
(Fig. 1). Although many structure frameworks such as cou-
marin, aniline, and indoline have been employed as good
electron donor unit, the small molecular organic dyes con-
taining the N-substituted carbazole structural motif have
been little explored for DSSCs.
Dye-sensitized solar cells (DSSCs) have attracted great
attention over the last 15 years owing to their prospect of
high energy conversion efficiency and low production
cost.1 Until now, however, only few photosensitizers based
on ruthenium metal complexes have achieved solar-to-elec-
tric power conversion over 10% under AM 1.5.2 Recently,
several groups have developed metal free organic sensitizers
to overcome the prohibitive cost of ruthenium metal com-
plexes, and the impressive photovoltaic performance has
been obtained with some organic coumarin,3 indoline,4 oli-
goene,5 merocyanine,6 and hemicyanine7 dyes having effi-
ciencies in the range of 5w8%. However, many organic
dyes have often presented the low conversion efficiency
and low operation stability compared to metal complexes.
The major factor for the low conversion efficiency of many
organic dyes in the DSSCs is due to the formation of dye
aggregates on the semiconductor surface. Another issue of
organic dyes is the stability due to the formation of unstable
radical species during redox reaction cycles.
2. Results and discussion
The novel organic dyes JK-24–JK-27 were constructed by
the stepwise synthetic protocol illustrated in Scheme 1.
For the synthesis of well-defined model compounds a mono-
functional carbazole unit substituted in the 3-position is re-
quired. The monohalogenated carbazole 1 was synthesized
by iodination with periodic acid dihydrate and iodine. Due
to two possibilities of N-arylation in 3-iodocarbazole, firstly
we introduced thiophene moieties. The carbazolyl mono-
and bithiophenes 2 and 3 were obtained by coupling 3-iodo-
carbazole 1 with tetrakis(triphenylphosphine)palladium(0),
dimethylformamide, and stannylthiophene units according
to the Stille reaction conditions.10 Fluorene substituted
carbazolyl thiophene derivatives 4 and 5 were obtained by
Ullmann coupling reactions11 involving copper bronze, po-
tassium carbonate, and 18-crown-6. These thiophene deriv-
atives were converted into their corresponding thiophene
aldehydes 6 and 7 by lithiation with 2.5 equiv n-butyl lith-
ium and subsequent quenching with dimethylformamide in
89% and 86% excellent yield, respectively. An acetonitrile
solution of thiophene aldehyde derivatives and cyanoacetic
Very recently, we have designed and synthesized the novel
organic dyes containing dimethylfluorenyl unit to overcome
the low conversion efficiency and low operational stability.
The amorphous non-planar dimethylfluorenyl moiety was
introduced to prevent aggregation via molecular stacking
and to ensure greater resistance to degradation when ex-
posed to light and high-temperature.8 Also, we have been
interested in an excellent hole-transporting material such
as carbazole moiety, which has been widely drawn interest
Keywords: Carbazole; Organic dye; Dye-sensitized solar cell.
* Corresponding authors. Tel.: +82 41 860 1337; fax: +82 41 867 5396;
e-mail: jko@korea.ac.kr
0040–4020/$ - see front matter Ó 2006 Published by Elsevier Ltd.
doi:10.1016/j.tet.2006.12.082

1914
D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
NC
N
S
N
COOH
S
COOH
S
NC
JK-24
JK-25
S
COOH
S
N
S
S
S
O
S
N
S
N
N
O
COOH
JK-26
JK-27
COOH
CN
S
COOH
CN
S
S
N
N
JK-28
JK-29
Figure 1. Structure of JK-24–JK-29.
acid was refluxed in the presence of piperidine for 6 h. Sol-
vent removal followed by purification by silica gel column
chromatography yielded JK-24 and JK-25 dyes as a red
solid. Similarly, condensation of thiophene aldehydes 6
and 7 with rhodanine-3-acetic acid and ammonium acetate
in acetic acid produced organic dyes JK-26 and JK-27.
due to the p–p* transition of the conjugated molecule.
The red-shifted band at about 20 nm of JK-24 compared
to JK-25 is due to the increase of the p-conjugation system
by thiophene. The result was also observed in the absorption
band of JK-26 and JK-27. The introduction of ethylene unit
also induced the red-shifted band at about 15 nm (JK-26 and
JK-29). On the other hand, the absorption band of JK-28
having a (4-(2,2-diphenylvinyl)phenyl moiety presented
slightly blue-shift compared to that of JK-24 having a fluo-
renyl moiety. The absorption band of JK-26 and JK-27
having the rhodanine-3-acetic acid as acceptor exhibited
red-shift at about 50 nm compared to that of JK-24 and
JK-25 having the cyanoacetic acid. From these results, we
can interpret that the rhodanine-3-acetic acid extends the
p-conjugation system of dye through the 4-oxo-2-thioxo-
thiazolidine ring. The absorption spectra of all the dyes
JK-24–JK-29 on TiO2 film are broadened due to the interac-
tion of the anchoring group with the surface titanium ions.
Similar broadening has been reported in several organic
dyes on TiO2 electrodes.13 Absorption band of JK-24, JK-
25, and JK-28 on TiO2 film is similar to that of the corre-
sponding solution spectra. However, the JK-27 and JK-29
on TiO2 film have blue-shifted band and JK-26 on TiO2
film has red-shifted band compared to those of the corre-
sponding solution spectra. From these results, we can ex-
plain that the N-substituted carbazole unit of dyes can
induce the non-planar structure by preventing aggregation
via molecular stacking but the ability of prevention may be
reduced in the larger conjugated dyes. We observed that
the dyes JK-24–JK-29 exhibited strong luminescence
The route to compounds JK-28 and JK-29 is shown in
Scheme 2. N-Arylation of 3-(thiophen-2-yl)carbazole 2
with 1-(2-(4-bromophenyl)-1-phenylvinyl)benzene under
Ullmann conditions produced the new carbazolyl thiophene
8. A formylation reaction with 2.5 equiv of n-butyl lithium
and dimethylformamide gave the aldehyde 9 in 82% yield.
Aldehyde, on reaction with cyanoacetic acid in the presence
of a catalytic amount of piperidine in acetonitrile, produced
the JK-28 dye. We have designed to insert the ethylene
group between two thiophenes. Coupling reaction of alde-
hyde 6 with (2-thienylmethyl)triphenylphosphonium bro-
mide under Horner–Emmons–Wittig coupling condition12
using potassium-tert-butoxide in THF led to 9-(9,9-di-
methyl-9H-fluoren-2-yl)-3-(5-(2-(thiophen-2-yl)vinyl)thio-
phen-2-yl)-9H-carbazole 10. This was then converted to the
aldehyde 11, which produced the dye JK-29 on treatment
with cyanoacetic acid.
UV–vis and fluorescence spectra of dyes in ethanol are
shown in Figure 2 and listed in Table 1, together with the
UV–vis spectra of the corresponding dyes absorbed on
TiO2 film. The absorption spectra of JK-24 and JK-25 dis-
play visible band at 411 and 435 nm, respectively, which is

D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
1915
I
S
SnBu3
1,2-dichlorobenzene
n
•
H
N
I2, HIO4 2H2O
H
N
H
N
Cu bronze, K2CO3,
18-crown-6
Pd(PPh3)4, DMF
H2SO4, AcOH, H2O
180°C, 48h
100°C, 12h
70°C, 1hour
S
N
S
I
1
n
n
2 : n = 1
3 : n = 2
4 : n = 1
5 : n = 2
COOH
CN
piperidine, CH3CN
80°C, 6h
n
S
N
COOH
NC
JK-24 : n = 1
JK-25 : n = 2
2.5 equiv n-BuLi
-78°C, THF, DMF
S
N
CHO
n
6 : n = 1
7 : n = 2
S
S
N
O
n
COOH
S
S
S
NH4-OAc, AcOH
N
120°C, 2h
N
O
COOH
JK-26 : n = 1
JK-27 : n = 2
Scheme 1. Synthesis of JK-24–JK-27.
COOH
Br
CN
Cu bronze, K2CO3,
18-crown-6
2.5 equiv n-BuLi
-78°C, THF, DMF
piperidine, CH3CN
80°C, 6h
2
180°C, 48h
N
N
S
S
N
S
COOH
CHO
NC
8
9
JK-28
HOOC
OHC
CN
S
S
S
COOH
CN
S
S
PPh3Br
S
S
2.5 equiv n-BuLi
-78°C, THF, DMF
6
piperidine, CH3CN
KtBuO
N
80°C, 6h
N
N
10
Scheme 2. Synthesis of JK-28 and JK-29.
11
JK-29

1916
D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
Figure 2. Absorption spectra in ethanol (dashed line) and on TiO2 film (straight line), and emission spectra (straight line) of JK-24 (a), JK-25 (b), JK-26 (c),
JK-27 (d), JK-28 (e), and JK-29 (f).
Table 1. Optical and electrochemical properties of JK-24–JK-29
d
Eox (DEp)/V
Dye
labsa/nm (3/M-1 cm-1)
labsb/nm
lemc/nm
E0–0e/V
ELUMOf/V
ELUMO/V versus NHE
JK-24
JK-25
JK-26
JK-27
JK-28
JK-29
411 (27,000)
435 (30,060)
469 (12,300)
489 (6012)
406 (21,500)
451 (29,500)
408
435
486
472
408
440
528
595
619
600
538
643
0.89 (0.38)
0.66 (0.58)
0.91 (0.23)
1.01 (0.14)
0.95 (0.34)
0.91 (0.26)
2.65
2.42
2.33
2.35
2.63
2.44
ꢀ1.76
ꢀ1.76
ꢀ1.42
ꢀ1.34
ꢀ1.68
ꢀ1.53
ꢀ1.13
ꢀ1.13
ꢀ0.79
ꢀ0.71
ꢀ1.05
ꢀ0.90
a
Absorption spectra were measured in ethanol.
Absorption spectra were measured on TiO2 film.
Emission spectra were measured in ethanol.
b
c
d
e
f
Redox potential of dyes on TiO2 was measured in CH3CN with 0.1 M (n-C4H9)4NPF6 with a scan rate of 50 mV sꢀ1 (vs Ag/Ag+).
E0–0 was determined from intersection of absorption and emission spectra in ethanol.
ELUMO was calculated by EoxꢀE0–0
.

D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
1917
maxima of 528–619 nm when they are excited within their
p–p* bands in an air-equilibrated solution at 298 K.
Electrochemical properties of the dyes JK-24–JK-29 were
scrutinized by cyclovoltammetry in acetonitrile with 0.1 M
tetrabutyl ammonium hexafluorophosphate using TiO2 film
with adsorbed dyes as working electrode. The results are
listed in Table 1. All dyes adsorbed on TiO2 film showed
the quasi-reversible coupling between 0.66 and 1.01 V ver-
sus Ag/Ag+ with separation within 0.58 V between anodic
and cathodic peaks. The ELUMO of dyes was calculated
from the redox potential and the energy at the crossing sec-
tion of absorption and emission spectra was observed in so-
lution. We observed that the Eox of JK-25 is the highest than
those of other dyes and the ELUMO of JK-27 is the lowest
than those of other dyes. The excited state oxidation poten-
tial (Eo*x) of the dyes (ꢀ0.71 to ꢀ1.13 V vs NHE) is much
negative than the conduction band level of TiO2 of approxi-
mately ꢀ0.5 V versus NHE.
In order to gain insight into the geometrical configuration
and photophysical properties, molecular orbital calculations
of the JK-24–JK-29 sensitizers were performed with the
TD-DFT on B3LYP/3-21G* (Fig. 3). The calculation illus-
trates that the HOMO is delocalized over the p-conjugated
system via fluorenyl or 4-(2,2-diphenylvinyl)phenyl group
through carbazole and the LUMO is delocalized over the
cyanoacrylic unit through thiophene (JK-24, JK-25, JK-28,
and JK-29). Examination of the HOMO and LUMO of these
dyes indicates that HOMO–LUMO excitation moved the
electron distribution from the carbazole unit to the cyano-
acrylic acid moiety and the photo-induced electron transfer
from the dyes to TiO2 electrode can be efficiently occurred
by the HOMO–LUMO transition. Interestingly, we could
observe that the LUMO of dyes containing the rhodanine-
3-acetic acid is delocalized over 4-oxo-2-thioxothiazolidine
ring but the delocalization is broken between 4-oxo-2-thioxo-
thiazolidine ring and acetic acid (JK-26 and JK-27). From
these results, we induce that the efficiencies of JK-26 and
JK-27 may be affected by these discontinuous electron dis-
tributions to acetic acid.
Figure 3. The frontier molecular orbitals of the HOMO and LUMO calcu-
lated with TD-DFT on B3LYP/3-21G* of JK-24 (a), JK-25 (b), JK-26 (c),
JK-27 (d), JK-28 (e), and JK-29 (f).
100
Figure 4 shows action spectra of monochromatic incident
photon-to-current conversion efficiencies (IPCEs) for
DSSCs based on JK-24–JK-29 (electrolyte: 0.6 M 3-hexyl-
1,2-dimethyl imidazolium iodide, 0.04 M I2, 0.025 M LiI,
0.05 M guanidium thiocyanate, and 0.28 M tert-butylpyri-
dine in acetonitrile). The IPCE for carbazole dye JK-24
reached about 78% at 408 nm, and carbazole dye JK-25
reached about 77% at 435 nm. These two dyes show a
relatively large photocurrent due to large IPCEs. The IPCE
spectrum of JK-27 sensitizer is red shifted by about 60 nm
compared to that of JK-25 as a result of p-conjugation.
However, the maximum IPCE value (8%) of JK-27 is much
lower than that of JK-25. A likely reason for this is that elec-
tron injection from the dye to TiO2 would be suppressed due
to a small energy gap between the LUMO level of the dye
and the conduction band edge of TiO2 decreased in particu-
lar by the addition of TBP. Photovoltaic performances of the
JK-24–JK-29 sensitized cells are summarized in Table 2.
Under standard global AM 1.5 solar condition, the JK-24
sensitized cell gave a short circuit photocurrent density (Jsc)
of 9.83 mA cmꢀ2, open circuit voltage (Voc) of 0.74 V, and
N719
JK24
JK25
JK26
JK27
JK28
JK29
80
60
40
20
0
350 400 450 500 550 600 650 700 750 800 850
Wavelength (nm)
Figure 4. Spectra of monochromatic incident photon-to-current conversion
efficiencies (IPCEs) for DSSC based on carbazole dyes: N719 (straight
line), JK-24 (dashed line), JK-25 (dotted line), JK-26 (dash dotted line),
JK-27 (dash dot dotted line), JK-28 (short dashed line), and JK-29 (short
dotted line).

1918
D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
Table 2. DSSC performance parameters of dyesa
aqueous solution as reported by the Gratzel group.17 The first
TiO2 layer of 13 mm thickness was prepared by screen print-
ing TiO2 paste (Solaronix, 13 nm anatase), and the second
scattering layer of 10 mm thickness (CCIC, HWP-400) was
coated. The TiO2 electrodes were immersed into the sample
(JK-24–JK-29) solution (0.3 mM in ethanol containing
10 mM 3a,7a-dihydroxy-5b-cholic acid (Cheno)) and kept
at room temperature for 18 h. Counter electrodes were pre-
pared by coating with a drop of H2PtCl6 solution (2 mg Pt
in 1 mL ethanol) on a FTO plate. The electrolyte was then
introduced into the cell, which was composed of 0.6 M
3-hexyl-1,2-dimethyl imidazolium iodide, 0.04 M iodine,
0.025 M LiI, 0.05 M guanidium thiocyanate, and 0.28 M
tert-butylpyridine in acetonitrile. For photovoltaic measure-
ment of the DSSCs, the cell was measured using 1000 W
xenon light source.
€
Dye
Jsc
Voc
(V)
FF
h
(%)
lmax (nm)
(IPCE (%))
(mA cmꢀ2
)
N719
16.29
9.83
11.50
3.76
1.39
7.85
9.11
0.75
0.74
0.68
0.62
0.55
0.69
0.61
0.64
0.70
0.66
0.77
0.73
0.71
0.68
7.84
5.02
5.15
1.79
0.55
3.87
3.76
530 (79)
400 (78)
430 (77)
470 (20)
490 (8)
JK-24
JK-25
JK-26
JK-27
JK-28
JK-29
420 (70)
430 (59)
Performances of DSSCs were measured with 0.18 cm2 working area.
a
a fill factor of 0.70, corresponding to an overall conversion
efficiency (h) of 5.02%. On the other hand, the JK-27 sensi-
tized cell gave a poor overall efficiency (h) of 0.55%. The
lower efficiency of the JK-27 sensitized cell compared to
the JK-24 and JK-25 may be attributable to the difficulty
in the photo-induced electron transfer from the LUMO of
dye to the conduction band of TiO2 because of a small
energy gap (0.21 V) between the two energy levels.
3.4. Characterization of DSSC
The cells were measured using 1000 W xenon light source,
whose power of an AM 1.5 Oirel solar simulator was cali-
brated by using KG5 filtered Si reference solar cell. The
incident photon-to-current conversion efficiency (IPCE)
spectra for the cells were measured on an IPCE measuring
system (PV measurements).
In summary, we have designed and synthesized six novel or-
ganic dyes containing N-aryl carbazole bridged by thiophene
units. We obtained a maximum solar energy to electricity
conversion efficiency (h) of 5.15% under AM 1.5 irradiation
with a DSSC based on JK-25. Our results suggest that the
development of alternative highly efficient organic dyes
comparable to ruthenium complexes can be possible through
the more sophisticated structural modifications, and these
works are now in progress.
3.5. 3-(Thiophen-2-yl)carbazole (2)
A stirred mixture of 1 (1.0 g, 3.41 mmol), tributyl(thiophen-
2-yl)stannane (1.27 g, 3.41 mmol), and Pd(PPh3)4 (0.197 g,
0.17 mmol) in dimethylformamide (30 mL) was stirred at
100 ꢁC for 12 h. After cooling the solution, H2O (50 mL)
was added to the solution and extracted with dichloro-
methane (50ꢂ5). The organic layer was separated and dried
over MgSO4. The solvent was removed in vacuo. The pure
product 3 was obtained by silica gel chromatography (eluant
MC/Hx¼1:2, Rf ¼0.4) as a white solid in 82% yield. Mp:
3. Experimental section
3.1. General methods
All reactions were carried out under an argon atmosphere.
Solvents were distilled from appropriate reagents. All
reagents were purchased from Sigma–Aldrich. 2-Iodo-9,9-
dimethylfluorene,8a 3-iodocarbazole,14 1-bromo-4-(2,2-di-
phenylvinyl)benzene,15 and (2-thienylmethyl)triphenyl-
phosphonium bromide16 were synthesized using a modified
procedure of previous references. 1H and 13C NMR spectra
were recorded on a Varian Mercury 300 spectrometer.
Elemental analyses were performed with a Carlo Elba Instru-
ments CHNS-O EA 1108 analyzer. Mass spectra were
recorded on a JEOL JMS-SX102A instrument. The absorp-
tion and photoluminescence spectra were recorded on a
Perkin–Elmer Lambda 2S UV–visible spectrometer and a
Perkin LS fluorescence spectrometer, respectively.
1
197 ꢁC. H NMR (acetone-d6): d 10.45 (br, 1H), 8.43 (s,
1H), 8.20 (d, 1H, J¼8.1 Hz), 7.72 (d, 1H, J¼8.1 Hz), 7.55
(d, 1H, J¼8.1 Hz), 7.53 (d, 1H, J¼8.1 Hz), 7.44 (d, 1H,
J¼3.6 Hz), 7.41 (t, 1H, J¼8.1 Hz), 7.38 (d, 1H, J¼5.1 Hz),
7.21 (t, 1H, J¼8.1 Hz), 7.12 (dd, 1H, J¼3.6, 5.1 Hz).
13C{1H} NMR (CDCl3/acetone-d6): d 145.8, 140.4, 139.4,
127.8, 125.9, 125.8, 124.2, 123.6, 123.0, 121.9, 120.2,
119.6, 119.1, 117.5, 111.1, 110.9. MS: m/z 249 [M+]. Anal.
Calcd for C16H11NS: C, 77.07; H, 4.45. Found: C, 76.88;
H, 4.28.
3.6. 3-(5-(Thiophen-2-yl)thiophen-2-yl)carbazole (3)
The product was synthesized according to the procedure as
described above for the synthesis of 2, giving a white solid
3.2. Cyclovoltagram
1
of the product 3 in 78% yield. Mp: 201 ꢁC. H NMR (ace-
Cyclic voltammetry was carried out with a BAS 100B (Bio-
analytical Systems, Inc.). A three-electrode system was used
and consisted of a gold disk, working electrode, and a plati-
num wire electrode. Redox potential of dyes on TiO2 was
measured in CH3CN with 0.1 M (n-C4H9)4NPF6 a scan
rate between 50 mV sꢀ1 (vs Fc/Fc+).
tone-d6): d 10.47 (br, 1H), 8.46 (s, 1H), 8.23 (d, 1H, J¼
7.2 Hz), 7.74 (d, 1H, J¼8.1 Hz), 7.59 (d, 1H, J¼7.2 Hz),
7.54 (d, 1H, J¼8.1 Hz), 7.43 (d, 1H, J¼3.6 Hz), 7.42 (t,
1H, J¼7.5 Hz), 7.41 (d, 1H, J¼3.6 Hz), 7.32 (d, 1H,
J¼5.1 Hz), 7.27 (d, 1H, J¼3.6 Hz), 7.22 (t, 1H, J¼7.5 Hz),
7.10 (dd, 1H, J¼5.1, 3.6 Hz). 13C{1H} NMR (acetone-d6):
d 145.6, 141.6, 140.7, 138.3, 135.9, 128.9, 126.9, 126.1,
125.7, 125.3, 124.6, 124.2, 123.8, 123.7, 121.3, 120.9,
118.4, 118.0, 112.3, 112.0. MS: m/z 359 [M+]. Anal. Calcd
for C20H13NS2: C, 72.47; H, 3.95. Found: C, 72.18; H, 3.85.
3.3. Fabrication of DSSC
For the preparation of DSSC, a washed FTO (Pilkington,
8 U sqꢀ1) glass plate was immerged in 40 mM TiCl4

D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
1919
3.7. 9-(9,9-Dimethylfluoren-2-yl)-3-(thiophen-2-yl)-
carbazole (4)
was warmed to room temperature and stirred overnight.
The reaction was quenched by the addition of dilute HCl
(1 mL) in 20 mL water and extracted with diethyl ether
(3ꢂ20 mL). The combined organic extract was dried over
anhydrous MgSO4 and filtered. The pure product 6 was
obtained by silica gel chromatography (eluant MC/Hx¼
A stirred mixture of 2 (1.40 g, 5.61 mmol), 2-iodo-9,9-di-
methylfluorene (1.97 g, 6.17 mmol), powdered anhydrous
potassium carbonate (1.55 g, 11.22 mmol), copper bronze
(0.36 g, 5.61 mmol), 18-crown-6 (0.22 g, 0.84 mmol), and
1,2-dichlorobenzene (50 mL) was refluxed for 48 h. After
cooling, the insoluble inorganic material was filtered off un-
der suction and the dark brown filtrate was collected. The
insoluble material was washed with dichloromethane
(3ꢂ30 mL). The combined filtrate and organic phase were
washed with dilute aqueous ammonia and water, and dried
over magnesium sulfate. The solvent was removed under re-
duced pressure. The pure product 4 was obtained by silica gel
chromatography (eluant MC/Hx¼1:3, Rf ¼0.4) to afford 4
(1.96 g) in 79% yield. Mp: 207 ꢁC. 1H NMR (CDCl3):
d 8.39 (s, 1H), 8.21 (d, 1H, J¼7.5 Hz), 7.94 (d, 1H, J¼
8.1 Hz), 7.82 (s, 1H, J¼8.1 Hz), 7.71 (d, 1H, J¼8.4 Hz),
7.64 (s, 1H), 7.55 (d, 1H, J¼8.1 Hz), 7.50 (t, 1H, J¼
7.5 Hz), 7.48 (d, 1H, J¼8.4 Hz), 7.46 (d, 1H, J¼8.1 Hz),
7.42 (d, 1H, J¼8.1 Hz), 7.41 (t, 1H, J¼7.5 Hz), 7.39 (t, 1H,
J¼7.5 Hz), 7.38 (d, 1H, J¼3.6 Hz), 7.33 (t, 1H, J¼7.5 Hz),
7.28 (d, 1H, J¼5.1 Hz), 7.13 (dd, 1H, J¼5.1, 3.6 Hz), 1.58
(s, 6H). 13C{1H} NMR (CDCl3): d 155.6, 153.9, 145.7,
141.6, 140.7, 138.7, 138.5, 136.5, 131.2, 130.9, 130.0,
128.1, 127.8, 127.4, 126.9, 126.4, 126.9, 124.7, 123.9,
123.4, 122.9, 122.4, 121.5, 121.3, 120.6, 120.3, 117.9,
110.3, 47.3, 27.3. MS: m/z 441 [M+]. Anal. Calcd for
C31H23NS: C, 84.32; H, 5.25. Found: C, 84.04; H, 5.14.
1
1:2, Rf¼0.3) to afford 6 in 89% yield. Mp: 226 ꢁC. H
NMR (CDCl3): d 9.95 (s, 1H), 8.74 (s, 1H), 8.38 (d, 1H,
J¼7.5 Hz), 8.14 (d, 1H, J¼7.5 Hz), 7.99 (d, 1H, J¼
3.9 Hz), 7.96 (d, 1H, J¼8.1 Hz), 7.90 (d, 1H, J¼8.4 Hz),
7.86 (s, 1H), 7.74 (d, 1H, J¼4.5 Hz), 7.64 (d, 1H,
J¼8.1 Hz), 7.63 (t, 1H, J¼7.5 Hz), 7.55 (d, 1H, J¼8.4 Hz),
7.49 (t, 1H, J¼7.5 Hz), 7.43 (d, 1H, J¼6.9 Hz), 7.42 (t,
1H, J¼7.5 Hz), 7.38 (d, 1H, J¼6.9 Hz), 7.35 (t, 1H,
J¼7.5 Hz), 1.61 (s, 6H). 13C{1H} NMR (CDCl3): d 182.7,
156.1, 155.7, 153.9, 141.8, 141.7, 141.6, 139.1, 138.4,
137.9, 136.1, 127.9, 127.4, 126.9, 125.9, 125.3, 124.8,
124.1, 123.2, 123.0, 122.9, 121.4, 121.3, 120.7, 120.6,
120.4, 118.6, 110.6, 110.4, 47.3, 27.2. MS: m/z 469 [M+].
Anal. Calcd for C32H23NOS: C, 81.85; H, 4.94. Found: C,
81.58; H, 4.79.
3.10. 5-(5-(9-(9,9-Dimethylfluoren-2-yl)carbazol-6-yl)-
thiophen-2-yl)thiophene-2-carbaldehyde (7)
The product was synthesized according to the procedure as
described above for the synthesis of 6, giving a yellow solid
of the product 7 in 86% yield. Mp: 234 ꢁC. 1H NMR
(CDCl3): d 9.84 (s, 1H), 8.37 (s, 1H), 8.21 (d, 1H, J¼
7.8 Hz), 7.92 (d, 1H, J¼8.1 Hz), 7.81 (d, 1H, J¼8.1 Hz),
7.66 (d, 1H, J¼8.4 Hz), 7.63 (d, 1H, J¼3.9 Hz), 7.62 (s,
1H), 7.51 (d, 1H, J¼8.1 Hz), 7.50 (t, 1H, J¼7.5 Hz), 7.47
(d, 1H, J¼8.1 Hz), 7.46 (t, 1H, J¼7.5 Hz), 7.42 (d, 1H,
J¼8.4 Hz), 7.41 (t, 1H, J¼7.5 Hz), 7.36 (d, 1H, J¼8.1 Hz),
7.34 (t, 1H, J¼7.5 Hz), 7.34 (d, 1H, J¼3.6 Hz), 7.29 (d,
1H, J¼3.6 Hz), 7.23 (d, 1H, J¼3.9 Hz), 1.58 (s, 6H).
13C{1H} NMR (CDCl3): d 182.5, 155.6, 153.9, 147.7,
141.7, 141.2, 141.0, 138.9, 138.4, 137.7, 136.2, 134.0,
127.8, 127.4, 127.3, 126.7, 125.8, 125.7, 124.3, 124.0,
123.9, 123.7, 123.3, 123.2, 122.9, 121.4, 121.3, 120.6,
120.5, 120.3, 117.8, 110.5, 110.3, 47.3, 27.2. MS: m/z 551
[M+]. Anal. Calcd for C36H25NOS2: C, 78.27; H, 4.57.
Found: C, 78.01; H, 4.51.
3.8. 9-(9,9-Dimethylfluoren-2-yl)-3-(5-(thiophen-2-yl)-
thiophen-2-yl)carbazole (5)
The product was synthesized according to the procedure as
described above for the synthesis of 4, giving a white solid
of the product 5 in 76% yield. Mp: 211 ꢁC. 1H NMR
(CDCl3): d 8.38 (s, 1H), 8.21 (d, 1H, J¼7.5 Hz), 7.94 (d,
1H, J¼8.1 Hz), 7.81 (d, 1H, J¼8.1 Hz), 7.69 (d, 1H,
J¼8.7 Hz), 7.63 (s, 1H), 7.54 (d, 1H, J¼8.1 Hz), 7.52 (t,
1H, J¼7.5 Hz), 7.48 (d, 1H, J¼8.4 Hz), 7.45 (d, 1H,
J¼8.7 Hz), 7.41 (t, 1H, J¼7.5 Hz), 7.39 (t, 1H, J¼7.5 Hz),
7.35 (d, 1H, J¼8.4 Hz), 7.33 (t, 1H, J¼7.5 Hz), 7.28 (d,
1H, J¼3.9 Hz), 7.23 (d, 1H, J¼3.9 Hz), 7.22 (d, 1H,
J¼5.1 Hz), 7.20 (d, 1H, J¼3.6 Hz), 7.05 (dd, 1H, J¼3.6,
5.1 Hz), 1.57 (s, 6H). 13C{1H} NMR (CDCl3): d 155.6,
153.9, 144.6, 141.7, 140.7, 138.8, 138.5, 137.9, 136.5,
135.8, 127.9, 127.8, 127.4, 126.5, 125.9, 124.8, 124.4,
124.2, 124.1, 124.0, 123.5, 123.4, 122.9, 122.8, 121.5,
121.3, 120.7, 120.4, 120.3, 117.6, 110.4, 110.2, 47.3, 27.3.
MS: m/z 523 [M+]. Anal. Calcd for C35H25NS2: C, 80.27;
H, 4.81. Found: C, 79.96; H, 4.73.
3.11. 2-Cyano-3-(5-(9-(9,9-dimethylfluoren-2-yl)-
carbazol-6-yl)thiophen-2-yl)acrylic acid (JK-24)
A mixture of 6 (0.3 g, 0.64 mmol) and cyanoacetic acid
(0.082 g, 0.96 mmol) was vacuum-dried and added aceto-
nitrile (20 mL) and piperidine (0.063 mL). The solution was
refluxed for 6 h. After cooling the solution, the organic layer
was removed invacuo. The pure product JK-24 was obtained
by silica gel chromatography (eluant EA/MeOH¼10:1,
Rf ¼0.2) to afford JK-24 (0.19 g) in 89% yield. Mp:
3.9. 5-(9-(9,9-Dimethylfluoren-2-yl)carbazol-6-yl)-
thiophene-2-carbaldehyde (6)
1
251 ꢁC. H NMR (DMSO-d6): d 8.77 (s, 1H), 8.49 (s, 1H),
8.43 (d, 1H, J¼7.8 Hz), 8.13 (d, 1H, J¼8.1 Hz), 8.04 (d,
1H, J¼3.9 Hz), 7.96 (d, 1H, J¼8.1 Hz), 7.90 (s, 1H), 7.89
(d, 1H, J¼8.7 Hz), 7.84 (d, 1H, J¼3.9 Hz), 7.62 (d, 1H,
J¼8.1 Hz), 7.61 (d, 1H, J¼7.8 Hz), 7.52 (t, 1H, J¼7.5 Hz),
7.51 (d, 1H, J¼8.7 Hz), 7.47 (t, 1H, J¼7.5 Hz), 7.41 (t,
1H, J¼7.8 Hz), 7.40 (d, 1H, J¼8.7 Hz), 7.36 (t, 1H,
J¼7.5 Hz), 1.54 (s, 6H). 13C{1H} NMR (DMSO-d6):
d 163.8, 155.4, 154.5, 153.7, 146.5, 141.6, 141.0, 138.3,
Compound 4 (0.26 g, 0.59 mmol) dissolved in tetrahydro-
furan(20 mL)wascooledtoꢀ78 ꢁCunderN2. n-Butyllithium
(0.92 mL, 1.6 M solution in hexane, 1.47 mmol) was added
dropwise over 10 min with vigorous stirring. It was brought
to 0 ꢁC for 1 h and kept at this temperature for additional
1 h. Again the solution was cooled to ꢀ78 ꢁC and dry di-
methylformamide (1 mL) was added at once. The solution

1920
D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
137.7, 135.3, 134.1, 133.7, 127.8, 127.3, 127.1, 125.6, 125.1,
124.6, 124.1, 123.5, 122.9, 122.5, 121.6, 121.4, 121.2, 120.6,
120.5, 119.1, 118.6, 116.8, 110.8, 110.1, 46.9, 26.6. MS: m/z
536 [M+]. Anal. Calcd for C35H24N2O2S: C, 78.33; H, 4.51.
Found: C, 78.05; H, 4.44.
(DMSO-d6): d 191.6, 189.5, 179.1, 176.1, 171.5, 166.5,
160.0, 156.4, 155.4, 153.7, 145.8, 144.6, 143.7, 140.9,
140.1, 138.1, 137.8, 135.8, 135.5, 133.3, 125.5, 125.3,
124.2, 123.9, 123.4, 122.9, 122.6, 122.5, 121.6, 121.2,
120.5, 119.6, 115.1, 112.4, 110.5, 110.3, 105.1, 46.9, 26.6,
23.8. MS: m/z 724 [M+]. Anal. Calcd for C37H26N2O3S3:
C, 69.13; H, 4.08. Found: C, 69.01; H, 4.02.
3.12. 2-Cyano-3-(5-(5-(9-(9,9-dimethylfluoren-2-yl)car-
bazol-6-yl)thiophen-2-yl)-thiophen-2-yl)acrylic acid
(JK-25)
3.15. 9-(4-(2,2-Diphenylvinyl)phenyl)-3-(thiophen-2-yl)-
carbazole (8)
The product was synthesized according to the procedure as
described above for the synthesis of JK-24, giving a red solid
The product was synthesized according to the procedure as
described above for the synthesis of 4, giving a white solid
of the product 8 in 68% yield. Mp: 214 ꢁC. 1H NMR
(CDCl3): d 8.45 (s, 1H), 8.24 (d, 1H, J¼7.5 Hz), 7.74 (d,
1H, J¼8.4 Hz), 7.54–7.32 (m, 20H), 7.19 (dd, 1H, J¼5.1,
3.9 Hz), 7.15 (s, 1H). 13C{1H} NMR (CDCl3): d 145.9,
145.3, 143.9, 143.2, 142.5, 141.5, 141.0, 140.2, 137.2,
135.5, 131.2, 130.4, 130.1, 129.0, 128.5, 128.2, 127.8,
127.5, 127.0, 126.7, 126.4, 125.8, 125.4, 124.5, 123.7,
123.6, 123.2, 122.3, 120.6, 120.1, 119.6, 118.0, 111.4,
110.8. MS: m/z 503 [M+]. Anal. Calcd for C36H25NS: C,
85.85; H, 5.00. Found: C, 85.64; H, 4.86.
1
of the product JK-25 in 86% yield. Mp: 258 ꢁC. H NMR
(DMSO-d6): d 8.66 (s, 1H), 8.40 (d, 1H, J¼8.1 Hz), 8.11 (d,
1H, J¼7.8 Hz), 8.07 (s, 1H), 7.94 (d, 1H, J¼8.1 Hz), 7.88
(s, 1H), 7.81 (d, 1H, J¼7.8 Hz), 7.66 (d, 1H, J¼3.9 Hz),
7.61 (m, 3H), 7.53 (d, 1H, J¼3.9 Hz), 7.49–7.32 (m, 7H),
1.53 (s, 6H). 13C{1H} NMR (DMSO-d6): d 162.8, 155.4,
154.5, 153.7, 145.2, 141.2, 140.8, 140.0, 139.9, 138.1,
137.8, 136.5, 136.2, 135.7, 135.6, 133.7, 127.8, 127.3,
127.1, 126.9, 125.9, 125.5, 125.4, 124.2, 124.0, 123.4,
122.9, 122.7, 121.6, 121.3, 121.11, 120.5, 119.5, 117.6,
110.5, 110.0, 49.9, 26.7. MS: m/z 618 [M+]. Anal. Calcd for
C39H26N2O2S2: C, 75.70; H, 4.24. Found: C, 75.42; H, 4.13.
3.16. 5-(9-(4-(2,2-Diphenylvinyl)phenyl)carbazol-6-yl)-
thiophene-2-carbaldehyde (9)
3.13. 2-(5-((5-(9-(9,9-Dimethylfluoren-2-yl)carbazol-6-
yl)thiophen-2-yl)methylene)-4-oxo-2-thioxothiazolidin-
3-yl)acetic acid (JK-26)
The product was synthesized according to the procedure as
described above for the synthesis of 6, giving a yellow solid
of the product 9 in 82% yield. Mp: 222 ꢁC. 1H NMR
(CDCl3): d 9.89 (s, 1H), 8.41 (s, 1H), 8.15 (d, 1H, J¼
7.5 Hz), 7.75 (d, 1H, J¼3.6 Hz), 7.69 (d, 1H, J¼8.4 Hz),
7.44 (d, 1H, J¼3.9 Hz), 7.42–7.27 (m, 17H), 7.25 (d, 1H,
J¼3.9 Hz), 7.08 (s, 1H). 13C{1H} NMR (CDCl3): d 182.7,
156.1, 143.9, 143.2, 141.6, 141.5, 141.4, 141.0, 140.2,
139.2, 137.9, 137.1, 136.7, 135.5, 131.1, 130.4, 129.0,
128.5, 128.0, 127.9, 127.8, 127.0, 126.8, 126.4, 125.9,
125.3, 124.7, 124.5, 124.1, 123.2, 120.8, 120.6, 118.5,
110.6, 110.4. MS: m/z 531 [M+]. Anal. Calcd for
C37H25NOS: C, 83.59; H, 4.74. Found: C, 83.36; H, 4.66.
To a stirred 6 (0.3 g, 0.64 mmol) in CH3COOH (30 mL)
were added rhodanine-3-acetic acid (0.13 g, 0.67 mmol)
and ammonium acetate (0.02 g, 0.26 mmol). Then the mix-
ture was heated to 120 ꢁC. The reaction was continued for
2 h at the temperature. Then the reaction mixture was al-
lowed to cool to room temperature. The solid was collected
by filtration and washed with water thoroughly. After drying
in air, the crude product was purified by column chromato-
graphy on silica gel with CH2Cl2/methanol (10:1, v/v) as el-
uant to give a black solid JK-26 in 74% yield. Mp: 261 ꢁC.
1H NMR (DMSO-d6): d 8.78 (s, 1H), 8.45 (d, 1H, J¼7.5 Hz),
8.13 (d, 1H, J¼8.1 Hz), 8.06 (s, 1H), 7.95 (d, 1H, J¼8.1 Hz),
7.92 (d, 1H, J¼7.5 Hz), 7.90 (s, 1H), 7.82 (m, 2H), 7.62 (d,
1H, J¼8.1 Hz), 7.61 (d, 1H, J¼8.4 Hz), 7.52–7.33 (m, 6H),
4.34 (s, 2H), 1.54 (s, 6H). 13C{1H} NMR (DMSO-d6):
d 191.9, 175.2, 167.1, 166.6, 155.4, 153.7, 153.1, 140.9,
140.6, 138.2, 137.8, 137.6, 135.6, 135.4, 127.8, 127.3,
127.0, 125.5, 124.9, 124.6, 124.5, 123.5, 122.9, 122.6,
121.6, 121.3, 121.2, 120.6, 120.5, 119.1, 118.2, 110.6,
110.1, 46.9, 26.7, 23.5. MS: m/z 642 [M+]. Anal. Calcd for
C41H28N2O3S4: C, 67.93; H, 3.89. Found: C, 68.90; H, 3.80.
3.17. 2-Cyano-3-(5-(9-(4-(2,2-diphenylvinyl)phenyl)car-
bazol-6-yl)thiophen-2-yl)-acrylic acid (JK-28)
The product was synthesized according to the procedure as
described above for the synthesis of JK-24, giving a red
1
solid of the product JK-28 in 78% yield. Mp: 255 ꢁC. H
NMR (DMSO-d6): d 8.62 (s, 1H), 8.34 (d, 1H, J¼7.5 Hz),
8.13 (s, 1H), 7.75 (d, 1H, J¼7.5 Hz), 7.73 (d, 1H,
J¼3.9 Hz), 7.66 (d, 1H, J¼3.9 Hz), 7.51–7.24 (m, 19H).
13C{1H} NMR (DMSO-d6): d 163.9, 152.5, 150.3, 149.8,
145.9, 143.7, 142.6, 142.4, 140.8, 140.6, 140.1, 139.8,
136.6, 136.4, 135.8, 135.3, 134.9, 130.9, 129.7, 129.2,
128.5, 127.9, 127.8, 127.2, 126.9, 126.8, 126.1, 125.4,
124.6, 123.5, 122.6, 121.1, 120.6, 119.3, 118.0, 110.5,
109.9, 108.3. MS: m/z 598 [M+]. Anal. Calcd for
C40H26N2O2S: C, 80.24; H, 4.38. Found: C, 79.94; H, 4.27.
3.14. 2-(5-((5-(5-(9-(9,9-Dimethylfluoren-2-yl)carbazol-
6-yl)thiophen-2-yl)thiophen-2-yl)methylene)-4-oxo-2-
thioxothiazolidin-3-yl)acetic acid (JK-27)
The product was synthesized according to the procedure as
described above for the synthesis of JK-26, giving a black
1
solid of the product JK-27 in 71% yield. Mp: 305 ꢁC. H
NMR (DMSO-d6): d 8.64 (s, 1H), 8.38 (d, 1H, J¼7.8 Hz),
8.09 (d, 1H, J¼8.1 Hz), 8.02 (s, 1H), 7.94 (d, 1H,
J¼8.1 Hz), 7.87 (s, 1H), 7.79 (d, 1H, J¼8.7 Hz), 7.73
(d, 1H, J¼3.9 Hz), 7.53 (d, 1H, J¼3.9 Hz), 7.63–7.30
(m, 10H), 4.37 (s, 2H), 1.52 (s, 6H). 13C{1H} NMR
3.18. 9-(9,9-Dimethylfluoren-2-yl)-3-(5-(2-(thiophen-
2-yl)vinyl)thiophen-2-yl)carbazole (10)
To a suspension of (2-thienylmethyl)triphenylphosphonium
bromide (0.65 g, 1.48 mmol) in THF (20 mL) at room

D. Kim et al. / Tetrahedron 63 (2007) 1913–1922
1921
temperature under N2 atmosphere was added tBuOK (0.17 g,
Acknowledgements
1.49 mmol). After cooling to 0 ꢁC, a solution of 6 (0.7 g,
1.48 mmol) with THF was added dropwise. The mixture
was stirred at 0 ꢁC for 1 h and at room temperature for
another 8 h. After being diluted with CH2Cl2, the mixture
was washed twice with water, and dried over anhydrous
Na2SO4. The solvent was evaporated and the residue was
purified by column chromatography on silica gel with
CH2Cl2/hexane (1:3, v/v) as eluant to give a white solid of
the product 10 in 73% yield. Mp: 238 ꢁC. 1H NMR
(CDCl3): d 8.44 (s, 1H), 8.26 (d, 1H, J¼7.8 Hz), 7.95 (d,
1H, J¼8.4 Hz), 7.84 (d, 1H, J¼7.2 Hz), 7.73 (d, 1H,
J¼8.7 Hz), 7.68 (s, 1H), 7.57–7.33 (m, 9H), 7.29 (d, 1H,
J¼3.9 Hz), 7.23 (d, 1H, J¼15.9 Hz), 7.22 (d, 1H, J¼
5.1 Hz), 7.13 (d, 1H, J¼3.9 Hz), 7.11 (d, 1H, J¼15.9 Hz),
7.05 (dd, 1H, J¼3.9, 5.1 Hz), 1.62 (s, 6H). 13C{1H} NMR
(CDCl3): d 155.7, 154.0, 144.5, 142.9, 141.7, 141.0, 140.8,
138.9, 138.6, 136.5, 128.3, 127.9, 127.5, 127.0, 126.8,
126.6, 126.3, 126.1, 125.9, 124.5, 124.4, 124.1, 123.5,
122.9, 122.5, 122.0, 121.5, 121.4, 121.0, 120.8, 120.5,
117.7, 110.5, 110.3, 47.4, 27.4. MS: m/z 549 [M+]. Anal.
Calcd for C37H27NS2: C, 80.84; H, 4.95. Found: C, 80.59;
H, 4.85.
We are grateful to the KOSEF through National Research
Laboratory (NRL 2005) program and BK21 (2006).
References and notes
€
€
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H. Inorg. Chem. 2003, 42, 7921; (c) Wang, P.; Klein, C.;
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Humphry-Baker, R.; Zakeeruddin, S. M.; Gratzel, M. J. Am.
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Gratzel, M. J. Am. Chem. Soc. 2001, 123, 1613.
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oh, Y.; Kasada, C.; Shinpo, A.; Suga, S.; Sayama, K.;
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4. (a) Horiuchi, T.; Miura, H.; Uchida, S. Chem. Commun. 2003,
3036; (b) Horiuchi, T.; Miura, H.; Sumioka, K.; Uchida, S.
J. Am. Chem. Soc. 2004, 126, 12218; (c) Schmidt-Mende, L.;
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3.19. 5-(2-(5-(9-(9,9-Dimethylfluoren-2-yl)carbazol-
6-yl)thiophen-2-yl)vinyl)thiophene-2-carbaldehyde (11)
The product was synthesized according to the procedure as
described above for the synthesis of 6, giving a yellow solid
1
of the product 11 in 73% yield. Mp: 247 ꢁC. H NMR
(CDCl3): d 9.82 (s, 1H), 8.38 (s, 1H), 8.20 (d, 1H,
J¼7.5 Hz), 7.92 (d, 1H, J¼8.1 Hz), 7.81 (d, 1H,
J¼7.8 Hz), 7.67 (d, 1H, J¼8.7 Hz), 7.63 (s, 1H), 7.60 (d,
1H, J¼3.9 Hz), 7.53–7.33 (m, 8H), 7.28 (d, 1H,
J¼3.9 Hz), 7.23 (d, 1H, J¼15.9 Hz), 7.11 (d, 1H, J¼
3.9 Hz), 7.07 (d, 1H, J¼3.3 Hz), 6.99 (d, 1H, J¼15.9 Hz),
1.58 (s, 6H). 13C{1H} NMR (CDCl3): d 182.4, 155.7,
154.0, 152.4, 146.7, 141.7, 141.3, 141.0, 139.7, 138.9,
138.4, 137.4, 136.3, 129.9, 127.8, 127.4, 126.6, 126.2,
125.9, 124.4, 124.0, 123.3, 123.2, 123.0, 122.9, 121.4,
121.3, 120.7, 120.6, 120.5, 120.3, 119.4, 117.8, 110.5,
110.3, 47.3, 27.2. MS: m/z 577 [M+]. Anal. Calcd for
C38H27NOS2: C, 79.00; H, 4.71. Found: C, 78.78; H, 4.57.
€
S.; Uchida, S.; Gratzel, M. Adv. Mater. 2005, 17, 813; (d) Ito,
S.; Zakeeruddin, S. M.; Humphry-Baker, R.; Liska, P.;
ꢀ
Charvet, R.; Comte, P.; Nazeeruddin, M. K.; Pechy, P.;
Takada, M.; Miura, H.; Uchida, S.; Gratzel, M. Adv. Mater.
€
2006, 18, 1202.
5. (a) Hara, K.; Kurashige, M.; Ito, S.; Shinpo, A.; Suga, S.;
Sayama, K.; Arakawa, H. Chem. Commun. 2003, 252; (b)
Kitamura, T.; Ikeda, M.; Shigaki, K.; Inoue, T.; Anderson,
N. A.; Ai, X.; Lian, T.; Yanagida, S. Chem. Mater. 2004, 16,
1806; (c) Hara, K.; Sato, T.; Katoh, R.; Furube, A.;
Yoshihara, T.; Murai, M.; Kurashige, M.; Ito, S.; Shinpo, A.;
Suga, S.; Arakawa, H. Adv. Funct. Mater. 2005, 15, 246.
6. (a) Sayama, K.; Tsukagoshi, S.; Hara, K.; Ohga, Y.; Shinpou,
A.; Abe, Y.; Suga, S.; Arakawa, H. J. Phys. Chem. B 2002,
106, 1363; (b) Sayama, K.; Hara, K.; Mori, N.; Satsuki, M.;
Suga, S.; Tsukagoshi, S.; Abe, Y.; Sugihara, H.; Arakawa, H.
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3.20. 2-Cyano-3-(5-(2-(5-(9-(9,9-dimethylfluoren-2-yl)-
carbazol-6-yl)thiophen-2-yl)vinyl)thiophen-2-yl)acrylic
acid (JK-29)
The product was synthesized according to the procedure as
described above for the synthesis of JK-24, giving a red
7. (a) Yao, Q.-H.; Shan, L.; Li, F.-Y.; Yin, D.-D.; Huang, C.-H.
New J. Chem. 2003, 27, 1277; (b) Wang, J.-S.; Li, F.-Y.;
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1
solid of the product JK-29 in 85% yield. Mp: 284 ꢁC. H
NMR (DMSO-d6): d 8.61 (s, 1H), 8.36 (d, 1H, J¼7.8 Hz),
8.12 (d, 1H, J¼8.1 Hz), 8.07 (s, 1H), 7.95 (d, 1H,
J¼7.8 Hz), 7.88 (s, 1H), 7.77 (t, 1H, J¼8.4 Hz), 7.68 (d,
1H, J¼7.5 Hz), 7.63–7.31 (m, 12H), 7.19 (d, 1H,
J¼15.9 Hz), 1.54 (s, 6H). 13C{1H} NMR (DMSO-d6):
d 163.3, 162.6, 161.4, 159.4, 155.3, 153.7, 149.7, 146.9,
144.6, 141.2, 140.8, 140.0, 139.8, 138.1, 137.7, 135.7,
135.6, 132.2, 129.9, 127.7, 127.2, 126.8, 125.8, 125.5,
124.2, 123.9, 123.6, 123.3, 122.8, 122.6, 121.5, 121.2,
120.9, 120.4, 119.2, 117.3, 110.5, 109.9, 46.8, 26.6. MS:
m/z 644 [M+]. Anal. Calcd for C41H28N2O2S2: C, 76.37;
H, 4.38. Found: C, 76.14; H, 4.21.
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1922
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€
13. (a) N€uesch, F.; Moser, J. E.; Shklover, V.; Gratzel, M. J. Am.
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