Synthesis and optical characterization of unsymmetrical oligophenylenevinylenes

Article abstract of DOI:10.1016/S0040-4020(02)00003-0

An efficient route to highly soluble unsymmetrical oligo(phenylenevinylenes) (OPVs) has been developed. The OPVs are end-substituted with donor alkoxy and acceptor sulfonyl groups for charge polarization and incorporate a methacrylate unit suitable for co-polymerization. The absorption and excitation spectra of the OPVs and their precursors have been examined; vibronic features are noted, and π-system lengthening and introduction of polarizing substituents red-shift the spectral maxima.

Full text of DOI:10.1016/S0040-4020(02)00003-0

TETRAHEDRON
Pergamon
Tetrahedron 58 (2002) 1425±1432
Synthesis and optical characterization of unsymmetrical
oligophenylenevinylenes
Anke C. Freydank,a,b,p Mark G. Humphrey,b Reiner W. Friedricha and Barry Luther-Daviesa
aLaser Physics Centre, Research School of Physical Sciences and Engineering, Australian National University,
Canberra, ACT 0200, Australia
bDepartment of Chemistry, Australian National University, Canberra, ACT 0200, Australia
Received 2 July 2001; revised 23 November 2001; accepted 20 December 2001
AbstractÐAn ef®cient route to highly soluble unsymmetrical oligo(phenylenevinylenes) (OPVs) has been developed. The OPVs are end-
substituted with donor alkoxy and acceptor sulfonyl groups for charge polarization and incorporate a methacrylate unit suitable for co-
polymerization. The absorption and excitation spectra of the OPVs and their precursors have been examined; vibronic features are noted, and
p-system lengthening and introduction of polarizing substituents red-shift the spectral maxima. q 2002 Elsevier Science Ltd. All rights
reserved.
1. Introduction
solubility of the oligo-PPV derivatives. The optical proper-
ties of the new and previously reported oligomers have been
examined, the results from which are also described herein.
Poly(p-phenylenevinylene) (PPV) is
a
p-conjugated
polymeric material with a range of interesting and useful
properties, such as large third-order nonlinearity,1 ef®cient
electroluminescence,2 and laser emission.3 However, the
unsubstituted PPV is not soluble in organic solvents,
which results in dif®culties of processing. Various PPV
derivatives and co-polymers have been synthesized to over-
come the solubility problem4±6 and a PPV-based material
has been shown to have potential for application in optical
signal processing.7
2. Results and discussion
2.1. Synthesis and characterization
We have previously reported the synthesis of CH2vCMe-
C(O)O(CH2)2O(CH2)2O±4-C6H4±(E)-CHvCH±4-C6H4±
(E)-CHvCH±4-C6H4SO2±n-C10H21 (24).12 In an important
step of this synthesis, 1,4-bis-p-xylene phosphonate diethyl
ester 1 reacted with 4-(decylthio)benzaldehyde 2 in a 3:1
ratio under Wittig±Horner conditions to give the mono-
substituted phosphonate 4, a key intermediate en route to
24. However, this reaction also afforded the undesired bis-
substituted product 6, which is sparingly soluble in all
organic solvents (Scheme 1). Repeating the reaction in a
1:1 ratio of 1,4-bis-p-xylene phosphonate ester 1 and alde-
hyde 2 afforded none of the desired product 4. Coupled to
the low yields of 4 were its unsatisfactory processing prop-
erties. We therefore replaced the n-decyl chain with a 2-
ethylhexyl unit. Repeating the above mentioned procedure
with 1,4-bis-p-xylene phosphonate ester 1 and 4-(2-ethyl-
hexylthio)benzaldehyde 3 in a ratio of 3:1 afforded less than
9% of the desired product 5 (Scheme 1); the symmetrical
compound 7 was obtained in 54% yield, oxidation of which
afforded 9 (Scheme 1). Product 7 with the 2-ethylhexyl
chain is highly soluble in common organic solvents. The
unsatisfactory yield of 5, though, has necessitated develop-
ment of a more ef®cient synthesis, described in Scheme 2.
The third-order nonlinear optical properties of PPV
originate from short p-conjugated segments,8 so systematic
investigation of the properties of oligomeric p-phenylene-
vinylenes (OPVs) are of signi®cant interest.5,9±11 However,
useful routes into unsymmetrical OPVs are comparatively
rare, and extant examples of OPVs often suffer from low
solubility. We report herein a newly developed synthesis of
highly soluble OPV derivatives with an electron-donating
poly(alkeneoxy) group and an electron-accepting alkyl-
sulfonyl substituent. This is an easier and more ef®cient
method of introducing the polarizing substituents into the
molecule than the method we described previously.12
Replacement of the n-decyl chain utilized in our earlier
work by a 2-ethylhexyl group results in vastly increased
Keywords: oligomers;
electronic spectra.
oligo(phenylenevinylene);
unsymmetrical;
p Corresponding author. Address: Laser Physics Centre, Research School
of Physical Sciences and Engineering, Australian National University,
Canberra, ACT 0200, Australia. Tel.: 161-2-6125-4230; fax: 161-2-
6125-0760; e-mail: acf111@rsphysse.anu.edu.au
The newly developed synthesis, which involved utilizing an
0040±4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020(02)00003-0

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A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
Scheme 1. Preparation of the symmetrically substituted OPVs 6±9.
unsymmetrical precursor, methyl 4-(bromomethyl)benzoate
10 (commercially available), proceeded via several facile
and high-yielding steps (Scheme 2). 4-(Diethoxyphos-
phonylmethyl)benzoic acid methyl ester 11 was prepared
by a Michaelis±Arbuzov reaction of 10 and triethylphos-
phite. The aldehydes 2, 3 and 21 were prepared by aromatic
nucleophilic substitution of ¯uorobenzaldehyde with the
appropriate thiol or ethylene glycol precursor in the
presence of base. The thiol precursor for 3, 2-ethylhexane
thiol 12, was prepared in high yields from the corresponding
bromo derivative. A subsequent Wittig±Horner reaction of
11 with the aldehydes 2 or 3 afforded the trans-con®gured
styrene derivatives 13 or 14, respectively, in high yields.
requires high solubility in organic solvents, and homo-
geneous distribution of chromophore in the putative poly-
meric matrix requires solubility in methyl methacrylate.
The newly developed monomer 25 affords improved solu-
bility in most common organic solvents compared to
monomer 24. For example, 25 is 34 and 45% w/w soluble
in CH2Cl2 and THF, respectively, whereas 24 is 4 and 6%
w/w soluble in these solvents, respectively. More import-
antly, 25 is about 1% w/w soluble in methyl methacrylate,
unlike 24 which is insoluble; 25 is thus a suitable precursor
for the preparation of homogeneous high-quality NLO
chromophore-containing polymethylmethacrylate ®lms.14
2.2. Spectroscopy
Reduction of the methyl ester group in 13 or 14 with LiAlH4
gave the alcohol 15 or 16, respectively, both in 98% yield.
The hydroxy group in 15 or 16 was then converted into the
bromomethyl groups in 17 or 18, respectively, under mild
conditions using freshly prepared triphenylphosphine dibro-
mide.13 Subsequent conversion to the phosphonate esters 4
or 5 proceeded easily with triethyl phosphite in nearly quan-
titative yield. The oxidation of the sulfanyl group in 4 or 5
was then achieved employing m-chloroperbenzoic acid
(MCPBA) to give the sulfonyl-containing compounds 19
or 20, respectively, in high yields. A second Wittig±Horner
reaction, with the glycol-bearing substituted aldehyde 21,
was then used to synthesize the donor±acceptor substituted
OPVs 22 and 23. Compounds 22 or 23 reacted with
methacrylic anhydride in the presence of dimethylamino-
pyridine (DMAP) as catalyst and triethylamine as base to
afford the methacrylate-functionalized monomers 24 or 25,
respectively.
The optical properties of the OPVs prepared in the current
studies have been assessed. The absorption, emission, and
excitation spectra were recorded in chloroform solution in a
10 mm quartz cuvette; results are collected in Table 1,
representative absorption spectra are displayed in Fig. 1,
and a representative superposition of absorption, emission
and excitation spectra for 25 is shown in Fig. 2.
A p±pp transition dominates the absorption spectra of the
compounds in the 300±400 nm region.10 The wavelength of
the absorption maximum of the stilbene derivatives is a
function of the inductive and mesomeric effects of the
para substituents. Thus, the methyl ester derivative 14
absorbs at 349 nm whereas the hydroxymethyl derivative
16 absorbs at higher energy (318 nm). Extending the p-
system in proceeding to the three-ring phenylenevinylene
compounds 23 and 25 results in a signi®cant red-shift. These
OPVs have UV±vis spectra which show vibronic features as
shoulders on the broad absorption band. The vibronic
features are more distinct on the spectra of the symmetrical
compounds than on those of the unsymmetrical compounds.
Compounds 22±25 are green-yellow and highly lumines-
cent. Compounds 24 and 25 are chromophore-containing
monomers which can, in principal, be co-polymerized
with methyl methacrylate. However, ease of processing

A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
1427
Scheme 2. Preparation of the unsymmetrically substituted OPVs 22±25.
Table 1. Absorption, emission and excitation data for compounds. All measurements as solutions in CHCl3
Compound
Absorption lmax (nm)
(1, [104 M21 cm21])
Emission lmax (nm)
(lex [nm])a
Excitation lmax (nm)
(lem [nm])b
5
7
9
14
16
18
20
23
25
327 (1.98)
379 (7.06)
368 (6.56)
349 (3.72)
318 (2.51)
339 (4.05)
325 (2.59)
374 (5.39)
372(5.36)
393 (332)
428/449/501 (379)
410/430/460/501 (365)
431 (349)
394 (331)
398 (340)
375 (325)
464/501 (374)
466/501 (375)
346/357/397/408 (428)
346/357/397 (430)
296/361 (395)
357/397 (456)
355/395 (466)
a
Excitation wavelength.
Emission wavelength.
b

1428
A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
Figure 1. Representative absorption spectra for stilbene derivatives 14 and 16, symmetrically substituted OPVs 7 and 9, and unsymmetrically substituted OPV
23.
The emission maxima vary with the electronic properties
of the para substituents, and p-system lengthening, in
a similar fashion to the absorption maxima. Thus, the
stilbene compounds show emission bands below 400 nm
whereas the OPVs 23 and 25 show strong emission bands
at around 465 nm. The bromo derivative 18 and the
sulfonyl-substituted phosphonate ester 20 afford typical
¯uorescence-quenched emission spectra with low quantum
yield. The emission spectra of 23 and 25 (Fig. 2) are nearly
identical and are independent of the excitation wavelength,
con®rming that the shoulder at 500 nm is compound-
derived and not instrumental in origin; applying different
excitation wavelengths in the shoulder regions of the
absorption spectrum of 25 (360, 375, 400, 420 nm) afforded
the same emission curve, but with varying intensity. The
symmetrical OPVs 7 and 9 emit light at higher energy
than the unsymmetrical OPVs 23 and 25, introduction of
polarizing substituents resulting in the expected shift to
lower energy.
The excitation spectra of the unsymmetrical OPVs 23 and
25 show two distinct maxima at 368 and 397 nm. In
contrast, the symmetrical OPV 7 shows four maxima at
346, 357, 397 and 408 nm in its excitation spectrum, and
the symmetrical OPV 9 shows three distinct maxima at 346,
357 and 397 nm together with several shoulders in its exci-
tation spectrum.
3. Conclusion
The studies detailed earlier have outlined an ef®cient
synthetic procedure to highly soluble unsymmetrical OPV
compounds. The generality of the synthetic procedure and
solubilizing in¯uence of the end-substituted 2-ethylhexyl
unit suggests that soluble longer-chain OPVs should be
readily accessible, without the need to attach side-
substituted solubilizing groups which generally result in
loss of co-planarity and hence loss of favourable electronic
Figure 2. Absorption, emission and excitation spectra for 25.

A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
1429
effects. The linear optical absorption, emission and excita-
tion spectra of the OPVs and their precursors have been
examined, and trends in spectral maxima rationalized. The
extended p-conjugative pathway, polarizing substituents,
and highly favourable solubility of 25 make it a promising
precursor for incorporation into PMMA, to prepare process-
able ®lms for electro-optic applications; studies directed
towards addressing this issue will be the subject of a subse-
quent report.
in triethylphosphite (1.0 g, 6 mmol) and the resultant
mixture re¯uxed for 2h. The triethylphosphite was then
removed by distillation, and 4 was obtained in 97% yield
as a colourless oil. Similar reaction of 18 (3.3 g, 7.9 mmol)
afforded 5 in 88% yield, also as a colourless oil.
Compound 4: C29H43O3PS (Mˆ502g mol 21); HRMS (EI)
1
calcd: 502.2670, found: 502.2671; H NMR (d, CDCl3):
7.41 (d, JHHˆ8.4 Hz, 4H, C6H4), 7.26 (d, JHHˆ8.4 Hz, 4H,
C6H4), 7.02(s, 2H, vCH), 4.00 (m, 4H, POCH2), 3.14 (d,
JPHˆ21.8 Hz, 2H, CH2P), 2.91 (t, JHHˆ7.4 Hz, 2H, SCH2),
1.63 (m, 2H, CH2), 1.40 (m, 2H, CH2), 1.23 (m, 18H, CH2,
POCH2CH3), 0.85 (t, JHHˆ6.6 Hz, 3H, CH3).
4. Experimental
1H and 13C NMR spectra were recorded using a Varian
Gemini-300 FT NMR spectrometer and are referenced to
residual CHCl3 (at 7.24 ppm) and CDCl3 (at 77.0 ppm),
respectively. EI (electron impact) mass spectra (both unit
resolution and high resolution (HR)) were recorded using a
VG Autospec instrument (70 eV electron energy, 8 kV
accelerating potential). Electronic absorption (UV±vis)
spectra were recorded using a Shimadzu UV-3101PC
spectrophotometer. Fluorescence and excitation spectra
were recorded using a SLM-Aminco 8100 Spectro¯uoro-
meter, OS-Version 1.09, 450 W Xenon arc lamp, scan rate
0.95 nm s21, voltage 1000 V, input and output slit: 2.0.
Infrared spectra were recorded as dichloromethane solutions
using a Perkin±Elmer system 2000 FT-IR spectrometer.
Compound 5: C27H39O3PS (Mˆ474 g mol21); HRMS (EI)
1
calcd: 474.2356, found: 474.2357; H NMR (d, CDCl3):
7.42(d, JHHˆ8.4 Hz, 2H, C6H4), 7.39 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.26 (m, 4H, C6H4), 7.02(s, 2H, vCH), 4.00 (m, 4H,
POCH2), 3.14 (d, JPHˆ21.8 Hz, 2H, PCH2), 2.89 (d,
JHHˆ6.1 Hz, 2H, SCH2), 1.62±1.25 (m, 9H, CHCH2), 1.23
(t, JHHˆ8.2Hz, 6H, POCH 2CH3), 0.86 (t, JHHˆ7.4 Hz, 6H,
CH3); 13C NMR (d, CDCl3): 137.1, 135.9, 134.5, 130.7 (4C,
i-C6H4), 130.0, 128.6 (4C, CH, C6H4), 127.9, 127.6 (2C,
CHvCH), 126.8, 126.5 (4C, CH, C6H4), 62.2 (d,
JPCˆ6.4 Hz, 2C, CH2OP), 38.8 (1C, CH), 37.8 (1C, CH2±
S), 33.4 (d, JPCˆ130.6 Hz, 1C, CH2P), 32.2, 28.7, 25.5, 22.9
(4C, CH2), 16.3 (2C, CH3CH2O), 14.0, 10.9 (2C, CH3); IR
(CH2Cl2): 2969s, 2931s, 2855w, 1510m, 1241s (PvO),
1055s (P±O±C), 1029s (O±C±C), 966s (O±C±C),
Methyl 4-(bromomethyl)benzoate 10 was purchased from
Sigma±Aldrich and used without further puri®cation.
841 cm21
.
4.1.3. 1,4-Bis[4-(2-ethylhexylthio)styryl]benzene 7. 1,4-
Bis-p-xylene phosphonate ester 1 (5.0 g, 13.2mmol) was
dissolved in 50 mL dimethoxyethane (DME) and cooled
to 08C. NaH (0.375 g, 15 mmol) was added and 3 (1.1 g,
4.4 mmol) in 30 mL DME was added dropwise to the solu-
tion. The solution was stirred for 1 h at 08C and 1 h at room
temperature. The unreacted NaH was quenched with water
and the solution was extracted with CH2Cl2. The extracts
were washed twice with water and dried over MgSO4,
®ltered and the solvent evaporated. The product was puri-
®ed by chromatography eluting with CH2Cl2/ethyl acetate to
give 54% 7 as a yellow solid and 9% 5.
4.1. General procedure for the synthesis of 2, 3 and 21
To an equimolar solution of 4-¯uorobenzaldehyde (7.0 g,
56 mmol) and 2-ethylhexane thiol 12 in 100 mL DMSO
were added 3 equiv. of freshly dried Na2CO3. The mixture
was heated for 6 h at 1608C under nitrogen atmosphere.
After cooling to room temperature, the reaction mixture
was poured into water and extracted twice with CH2Cl2,
dried over anhydrous MgSO4, and evaporated to dryness.
The crude product was then puri®ed by silica gel chromato-
graphy using CH2Cl2 as eluent to give 3 in 85% yield. Simi-
lar reactions employing n-decane thiol using CH2Cl2 as
eluent afforded 212 in 92% yield and diethylene glycol
using ethyl acetate afforded 2112 in 35% yield.
Compound 7: C38H50S2 (Mˆ570 g mol21); calcd: C 79.94,
H 8.83, S 11.23, found: C 79.90, H 8.52, S 11.05; mp 1448C;
1H NMR (d, CDCl3): 7.47 (s, 4H, C6H4), 7.41 (d,
JHHˆ8.5 Hz, 4H, C6H4), 7.27 (d, JHHˆ8.5 Hz, 4H, C6H4),
7.05 (s, 4H, vCH), 2.90 (d, JHHˆ6.2Hz, 4H, SCH 2), 1.62±
4.1.1. 4-(2-Ethylhexylthio)benzaldehyde 3. C15H22OS
(Mˆ250 g mol21); colourless oil, HRMS (EI) calcd:
1
250.1391, found: 250.1391; H NMR (d, CDCl3): 9.89 (s,
1.20 (m, 18H, CHCH2), 0.83 (t, JHHˆ6.7 Hz, 12H, CH3), 13
C
1H, CHO), 7.72(d, JHHˆ8.4 Hz, 2H, C6H4), 7.32(d,
NMR (d, CDCl3): 137.2, 136.6, 134.6 (6C, i-C6H4), 128.6
(4C, CH, C6H4), 127.9, 127.7 (4C, CHvCH), 126.8, 126.7
(8C, CH, C6H4), 38.8 (2C, CH), 37.8 (2C, CH2±SO2), 32.4,
28.9, 25.6, 22.9 (8C, CH2), 14.1, 10.8 (2C, CH3); IR
(CH2Cl2): 2959s, 2920s, 2865m, 2851m, 1512w, 1493w,
JHHˆ8.4 Hz, 2H, C6H4), 2.95 (d, JHHˆ6.2Hz, 2H, SCH ),
2
1.70±1.20 (m, 9H, CHCH2), 0.90 (m, 6H, CH3); 13C NMR
(d, CDCl3): 147.7, 132.9 (2C, i-C6H4), 129.9, 126.2 (4C,
CH, C6H4), 38.5 (1C, CH), 36.0 (1C, CH2S), 32.4, 28.7,
25.6, 22.9 (4C, CH2), 14.1, 10.7 (2C, CH3); IR (CH2Cl2):
2962s, 2928s, 2866m, 2853m, 1697s (CvO), 1588m,
1561m, 1457w, 1381w, 1303w, 2118m, 1170m, 1085m,
1465w, 909vs, 830s, 651w (S±C) cm21
.
837m, 817m cm21
.
4.1.4. 1,4-Bis[4-(2-ethylhexylsulfonyl)styryl]benzene 9.
Similar reaction with 7 (0.20 g, 0.35 mmol) as for 4 and 5
afforded 9 in 90% yield as yellow solid.
4.1.2. {{4-{2-[4-(Decylthio)phenyl]ethenyl}phenyl}methyl}-
phosphonic acid diethylester 4 and {{4-{2-[4-(2-ethyl-
hexylthio)phenyl]ethenyl}phenyl}methyl}phosphonic
acid diethylester 5. 17 (0.75 g, 1.63 mmol) was suspended
Compound 9: C38H50S2O2 (Mˆ602g mol 21); calcd: C
71.88, H 7.94, S 10.10, found: C 71.65, H 7.77, S 9.92;

1430
A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
mp 2018C; 1H NMR (d, CDCl3): 7.86 (d, JHHˆ8.5 Hz, 4H,
C6H4), 7.66 (d, JHHˆ8.5 Hz, 4H, C6H4), 7.55 (s, 4H, C6H4),
7.24 (d, JHHˆ16.3 Hz, 2H, vCH), 7.14 (d, JHHˆ16.3 Hz,
2H, vCH), 3.01 (d, JHHˆ6.0 Hz, 4H, SO2CH2), 1.91 (m,
2H, CH), 1.50±1.12 (m, 16H, CH2), 0.83 (m, 12H, CH3);
13C NMR (d, CDCl3): 142.4, 138.5, 136.6 (6C, i-C6H4),
131.8 (4C, CHvCH), 128.4, 127.4, 127.0 (12C, CH,
C6H4), 59.9 (2C, CH2±SO2), 34.4 (2C, CH), 32.4, 28.2,
Compound 13: C26H34SO2 (Mˆ410 g mol21); calcd: C
76.05, H 8.35, S 7.81, found: C 75.94, H 8.30, S 7.67; mp
1
1348C; H NMR (d, CDCl3): 8.02(d, JHHˆ8.4 Hz, 2H,
C6H4), 7.55 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.44 (d,
JHHˆ8.4 Hz, 2H, C6H4), 7.29 (d, JHHˆ8.4 Hz, 2H, C6H4),
7.15 (d, JHHˆ16.5 Hz, 1H, vCH), 7.08 (d, JHHˆ16.5 Hz,
1H, vCH), 3.92(s, 3H, OMe), 2.94 (t, JHHˆ7.4 Hz, 2H,
SCH2), 1.66 (m, 2H, CH2), 1.40 (m, 2H, CH2), 1.26 (m, 12H,
CH2), 0.87 (t, JHHˆ6.7 Hz, 3H, CH3).
25.7, 22.7 (8C, CH2), 14.1, 10.2(4C, CH ); IR (CH2Cl2):
3
2963s, 2932s, 2871m, 2862m, 1593s, 1465w, 1309s (SO2),
1146s (SO2), 1088m, 967m, 839m, 674 cm21
.
Compound 14: C24H30SO2 (Mˆ382g mol 21); calcd: C
75.35, H 7.90, S 8.38, found: C 75.05, H 7.69, S 7.99; mp
918C; 1H NMR (d, CDCl3): 8.01 (d, JHHˆ8.4 Hz, 2H, C6H4),
7.53 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.41 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.28 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.14 (d,
JHHˆ16.4 Hz, 1H, vCH), 7.05 (d, JHHˆ16.4 Hz, 1H,
vCH), 3.90 (s, 3H, OMe), 2.91 (d, JHHˆ6.1 Hz, 2H,
SCH2), 1.62±1.20 (m, 9H, CHCH2), 0.88 (t, JHHˆ6.7 Hz,
6H, CH3); 13C NMR (d, CDCl3): 167.0 (1C, CvO), 141.9,
139.1, 134.0, 130.7 (4C, i-C6H4), 130.1, 128.4, 127.3 (6C,
CH, C6H4), 126.9, 126.8 (2C, CHvCH), 126.3 (2C, CH,
C6H4), 52.2 (1C, CH3O), 38.9 (1C, CH), 37.6 (1C, CH2±
S), 32.4, 28.8, 25.6, 23.0 (4C, CH2), 14.1, 10.8 (2C, CH3);
IR (CH2Cl2): 2962s, 2928s, 2866m, 2853m, 1717vs (CvO),
1605s, 1506m, 1492m, 1436m, 1284vs (C±O), 1180m,
4.1.5. 4-(Diethoxyphosphonylmethyl)benzoic acid methyl
ester 11. A mixture of methyl 4-(bromomethyl)benzoate
10 (12.5 g, 54.5 mmol) and triethylphosphite (20 mL,
110 mmol) was stirred at 1608C under nitrogen atmosphere
for 2h. The excess triethylphosphite was removed by distil-
lation in vacuum. The product 11 was puri®ed by ¯ash
chromatography (CH2Cl2/gradient methanol, 5%)15 to afford
95% yield as a colourless oil.
1
Compound 11: C13H19O5P (Mˆ286 g mol21); H NMR (d,
CDCl3): 7.97 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.36 (dd,
JHHˆ8.4 Hz, JPHˆ2.5 Hz, 2H, C6H4), 4.00 (m, 4H, OCH2),
3.89 (s, 3H, OCH3), 3.18 (d, JPHˆ22.1 Hz, 2H, CH2P), l.23
(t, JHHˆ8.2Hz, 6H, POCH 2CH3).
1107m, 1091m, 969m, 845m, 810m cm21
.
4.1.6. 2-Ethylhexane thiol 12. KOH (33.66 g, 600 mmol)
was dissolved in 300 mL EtOH and H2S was bubbled
through the solution for 30 min. 2-Ethylhexyl bromide
(72.49 g, 375 mmol) was added to the reaction mixture
dropwise while H2S was continuously bubbled through.
The mixture was then warmed to 538C over 2h. The
reaction mixture was diluted with water and acidi®ed with
1 M HCl and extracted with diethyl ether. The ether
extracts were combined and dried with MgSO4 and the
ether was evaporated. The product was distilled at
388C (0.1 mmHg) to give 12 in 68% yield as a colourless
liquid.
4.1.8. 1-Hydroxymethyl-{4-[2-(4-decylthio)phenyl]ethenyl}-
benzene 15and 1-hydroxymethyl-{4-{2-[4-(2-ethylhexyl)-
thio]phenyl}ethenyl}benzene 16. 13 (4.56 g, 11.1 mmol)
in 70 mL THF was carefully added to a suspension of
LiAlH4 (0.456 g, 12mmol) in 100 mL THF under nitrogen
atmosphere. The reaction mixture was re¯uxed for 4 h.
After cooling to room temperature, the mixture was care-
fully quenched with a THF/water mixture to destroy remain-
ing LiAlH4. The mixture was then poured into water and the
solid was separated, washed with methanol and dried under
reduced pressure. The reduction of the methyl ester group
afforded 15 in 98% yield as a pale yellow solid. Similar
reaction of 14 (7.8 g, 20.4 mmol) gave 16 in 98% yield,
also as a pale yellow solid.
Compound 12: C8H18S (Mˆ146 g mol21); HRMS (EI)
1
calcd: 146.2927, found: 146.2926; H NMR (d, CDCl3):
2.52 (d, JHHˆ8.07 Hz, 1H, SCH2), 2.50 (d, JHHˆ8.07 Hz,
1H, SCH2), 1.45±1.20 (m, 9H, CHCH2), 0.87 (m, 6H, CH3),
13C NMR (d, CDCl3): 41.6 (1C, CH), 31.5 (1C, CH2±S),
28.8, 28.0, 24.7, 22.9 (4C, CH2), 14.1, 10.8 (2C, CH3); IR
(CH2Cl2): 2962s, 2930s, 2873m, 2860m, 2584w SH,
Compound 15: C25H34OS (Mˆ382g mol 21); calcd: C
78.48, H 8.96, S 8.38, found: C 78.25, H 8.64, S 8.27; mp
1
1518C; H NMR (d, CDCl3): 7.49 (d, JHHˆ8.3 Hz, 2H,
C6H4), 7.40 (d, JHHˆ8.3 Hz, 2H, C6H4), 7.37 (d,
JHHˆ8.3 Hz, 2H, C6H4), 7.26 (d, JHHˆ8.3 Hz, 2H, C6H4),
7.05 (s, 2H, vCH), 4.68 (d, JHHˆ6.0 Hz, 2H, CH2OH), 2.91
(t, JHHˆ6.4 Hz, 2H, SCH2), 1.64 (m, 2H, CH2), 1.40 (m, 2H,
CH2), 1.23 (m, 12H, CH2), 0.85 (t, JHHˆ6.7 Hz, 3H, CH3).
1459m, 1379w, 617w (C±S) cm21
.
4.1.7. 4-[2-(Decylthio)phenylethenyl]benzoic acid methyl
ester 13 and 4-{2-[4-(2-ethylhexyl)thio]phenylethenyl}-
benzoic acid methyl ester 14. To a solution of 11 (5.0 g,
5.5 mmol) in THF under nitrogen atmosphere was added
sodium hydride (0.65 g, 26 mmol). After cooling the
mixture to 08C, 4-(decylthio)benzaldehyde 2 (4.86 g,
5.5 mmol) in 50 mL THF was carefully added dropwise.
The reaction mixture was stirred for 1 h at room temperature
and then quenched with water. After neutralization with 2M
HCl, a white solid was obtained which was washed twice
with petroleum spirit and dried under high vacuum to give
13 in 78% yield as a white solid. Similar reaction with 3
(5.15 g, 20.6 mmol) afforded 14 in 82% yield as a white
solid.
Compound 16: C23H30SO (Mˆ354 g mol21); calcd: C
77.92, H 8.53, S 9.04, found: C 77.72, H 8.44, S 9.03; mp
968C; 1H NMR (d, CDCl3): 7.48 (d, JHHˆ8.4 Hz, 2H, C6H4),
7.39 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.33 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.26 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.04 (s, 2H, vCH),
4.67 (s, 2H, CH2OH), 2.89 (d, JHHˆ6.2Hz, 2H, SCH ),
2
1.62±1.28 (m, 9H, CHCH2), 0.87 (t, JHHˆ7.2Hz, 6H,
CH3); 13C NMR (d, CDCl3): 145.5, 140.1, 136.8, 134.4
(4C, i-C6H4), 128.7 (2C, CH, C6H4), 128.2, 127.7 (2C,
CHvCH), 127.4, 126.9, 126.7 (6C, CH, C6H4), 65.2(1C,
CH2±OH), 38.9 (1C, CH), 37.9 (1C, CH2±S), 32.4, 28.8,
25.6, 23.0 (4C, CH2), 14.2, 10.8 (2C, CH3); IR (CH2Cl2):

A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
1431
3596w (OH), 2956s, 2925s, 2875m, 2857m, 1210s (C±O),
1093m, 1037m, 1009m, 966m, 827m cm21
JHHˆ8.4 Hz, JHHˆ2.4 Hz, 2H, C6H4), 7.21 (d, JHH
ˆ
5.3 Hz, 1H, vCH), 7.09 (d, JHHˆ5.3 Hz, 1H, vCH), 4.02
(m, 4H, POCH2), 3.16 (d, JPHˆ21.8 Hz, 2H, PCH2), 3.06 (t,
JHHˆ7.0 Hz, 2H, SO2CH2), 1.69 (m, 2H, CH2), 1.32(m, 2H,
.
4.1.9. 1-Bromomethyl-{4-[2-(4-decylthio)phenyl]ethenyl}-
benzene 17 and 1-bromomethyl-{4-{2-[4-(2-ethylhexyl)-
thio]phenyl}ethenyl}benzene 18. Triphenylphosphine
(0.84 g, 3.2mmol) was dissolved in CH 2Cl2 and the solution
cooled to 08C. An equimolar amount of bromine was care-
fully added to the solution to give Ph3PBr2.13 A suspension
of 15 (1.0 g, 2.6 mmol) in CH2Cl2 was added dropwise to
the Ph3PBr2 solution. The resultant mixture was then
re¯uxed for 2h. After the reaction was complete 10 mL of
MeOH were added dropwise to the mixture to destroy the
unreacted Ph3PBr2. The solvent was removed by evapora-
tion and the crude product dissolved in EtOH, heated for
10 min and then hot ®ltered. A pale yellow solid 17 was
obtained in 70%. Similar reaction of 16 (5.0 g, 14.1 mmol)
afforded 18, which was washed three times with MeOH and
dried to give pure 18 in 80% yield, also as a pale yellow
solid.
CH2), 1.24 (m, 18H, CH2, POCH2CH3), 0.86 (t, JHH
6.7 Hz, 3H, CH3).
ˆ
Compound 20: C27H39O5PS (Mˆ506 g mol21); HRMS (EI)
1
calcd: 506.2256, found: 506.2256; H NMR (d, CDCl3):
7.85 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.63 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.47 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.29 (dd, 2H,
JHHˆ8.4, 2.4 Hz, C6H4), 7.19 (d, JHHˆ16.6 Hz, 1H,
vCH), 7.08 (d, JHHˆ16.6 Hz, 1H, vCH), 4.02(m, 4H,
POCH2), 3.14 (d, JPHˆ21.8 Hz, 2H, PCH2), 3.00 (d,
JHHˆ6.9 Hz, 2H, SO2CH2), 1.90 (m, 1H, CH), 1.50±1.12
(m, 8H, CH2), 1.23 (t, JHHˆ7.2Hz, 6H, POCH 2CH3), 0.80
(m, 6H, CH3); 13C NMR (d, CDCl3): 142.6, 138.3, 135.0,
132.2 (4C, i-C6H4), 130.3, 130.2(2C, CH vCH), 128.4,
127.1, 126.9, 126.5 (8C, CH, C6H4), 62.2 (d, JPCˆ6.7 Hz,
2C, CH2OP), 59.9 (1C, CH2SO2), 34.4 (1C, CH), 33.6 (d,
JPCˆ126.7 Hz, 1C, CH2P), 32.4, 28.2, 25.7, 22.7 (4C, CH2),
16.3 (2C, CH3CH2O), 14.0, 10.2(2C, CH 3); IR (CH2Cl2):
2963s, 2931s, 2873m, 2862m, 1593m, 1512m, 1464m,
1404m, 1394m, 1308s (SO2), 1238s (PvO), 1143s (C±
SO2), 1089m, 1051s (P±O±C), 1028vs (O±C±C), 966s
Compound 17: C25H33BrS (Mˆ445 g mol21); calcd: C
67.40, H 7.47, Br 5.94, S 7.20, found: C 67.33, H 7.80, Br
5.68, S 6.95; mp 1248C; H NMR (d, CDCl3): 7.47 (d,
1
JHHˆ8.4 Hz, 2H, C6H4), 7.41 (d, JHHˆ8.4 Hz, 2H, C6H4),
7.37 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.28 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.06 (s, 2H, vCH), 4.51 (s, 2H, CH2Br), 2.93 (t,
JHHˆ7.4 Hz, 2H, SCH2), 1.65 (m, 2H, CH2), 1.42(m, 2H,
CH2), 1.26 (m, 12H, CH2), 0.87 (t, JHHˆ6.7 Hz, 3H, CH3).
(O±C±C), 848m cm21
.
4.1.11. 1-{4-[2-(2-Hydroxyethoxy)ethoxy]styryl}-4-(4-
decyl-sulfonylstyryl)benzene 22 and 1-{4-[2-(2-hydoxy-
ethoxy)ethoxy]styryl}-4-(4-(2-ethylhexylsulfonyl-styryl)
benzene 23. 19 (0.89 g, 1.67 mmol) in 50 mL THF was
stirred under nitrogen atmosphere at 08C. NaH (0.08 g,
3.2mmol) was carefully added, and then aldehyde 21
(0.35 g, 1.67 mmol) in 40 mL THF was added dropwise to
the reaction mixture. The reaction mixture was stirred for
2h at room temperature, and then quenched with water,
extracted twice with CH2Cl2 and washed twice with 1 M
HCl, and dried over MgSO4. The solvent was evaporated
and the remaining solid was dried. The yellow-green solid
22 was obtained in 78% yield. Similar reaction with 20
(3.0 g, 5.9 mmol) afforded 23 in 76% yield as a yellow-
green solid, puri®ed by precipitation with petrol from a
CH2Cl2 solution.
Compound 18: C23H29BrS (Mˆ417 g mol21); calcd: C
66.18, H 7.00, Br 19.14, S 7.68, found: C 66.33, H 6.66,
Br 19.26, S 7.63; mp 868C; H NMR (d, CDCl3): 7.45 (d,
1
JHHˆ8.4 Hz, 2H, C6H4), 7.39 (d, JHHˆ8.4 Hz, 2H, C6H4),
7.35 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.27 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.04 (s, 2H, vCH), 4.50 (s, 2H, CH2Br), 2.90 (d,
JHHˆ6.1 Hz, 2H, SCH2), 1.64±1.20 (m, 9H, CHCH2), 0.87
(t, JHHˆ7.3 Hz, 6H, CH3); 13C NMR (d, CDCl3): 137.5,
136.8, 134.2, 132.1 (4C, i-C6H4), 129.4 (2C, CH, C6H4),
128.7, 128.5 (2C, CHvCH), 127.2, 126.8, 126.7 (6C, CH,
C6H4), 38.8 (1C, CH), 37.7 (1C, CH2±S), 33.5 (1C, CH2Br),
32.3, 28.7, 25.5, 22.9 (4C, CH2), 14.2, 10.8 (2C, CH3); IR
(CH2Cl2): 2962s, 2928s, 2866m, 2853m, 1560m, 1513m,
1492m, 1279s (CH2±Br), 1229m, 1087m, 966m, 830m,
599s (CH2Br) cm21
.
Compound 22: C36H46O5S (Mˆ590 g mol21); calcd: C
73.19, H 7.85, S 5.43, found: C 72.99, H 7.65, S 5.24; mp
1
4.1.10. {{4-{2-[4-(Decylsulfonyl)phenyl]ethenyl}phenyl}-
methyl}phosphonic acid diethylester 19 and {{4-{2-[4-(2-
ethylhexylsulfonyl)phenyl]ethenyl}phenyl}methyl}phos-
phonic acid diethylester 20. 4 (0.84 g, 1.67 mmol) in
CH2Cl2 was cooled to 08C and m-chloroperbenzoic acid
(MCPBA) (0.574 g, 3.34 mmol) in CH2Cl2 was added
slowly. After 2h the resultant solid was isolated, washed
twice with Na2CO3 solution, and dried over MgSO4. The
solvent was removed by evaporation and the sulfonyl
compound 19 was obtained in 98% yield as a colourless
oil. Similar reaction with 5 (3.7 g, 7.8 mmol) afforded 20
in 95% yield, also as a colourless oil.
2608C; H NMR (d, CDCl3): 7.84 (d, JHHˆ8.2Hz, 2H,
C6H4), 7.64 (d, JHHˆ8.2Hz, 2H, C H4), 7.50 (s, 4H,
6
C6H4), 7.45 (d, JHHˆ8.2Hz, 2H, C H4), 7.23 (d, JHH
ˆ
6
16.3 Hz, 1H, vCH), 7.11 (d, JHHˆ16.3 Hz, 1H, vCH),
7.09 (d, JHHˆ16.3 Hz, 1H, vCH), 6.97 (d, JHHˆ16.3 Hz,
1H, vCH), 6.91 (d, JHHˆ8.2Hz, 2H, C H4), 4.15 (t,
6
JHHˆ4.8 Hz, 2H, OCH2), 3.87 (t, JHHˆ4.8 Hz, 2H, OCH2),
3.77 (t, JHHˆ4.8 Hz, 2H, OCH2), 3.67 (t, JHHˆ4.8 Hz, 2H,
OCH2), 3.07 (t, JHHˆ5.7 Hz, 2H, SO2CH2), 1.69 (m, 2H,
CH2), 1.32(m, 2H, CH 2), 1.24 (m, 12H, CH2), 0.86 (t,
JHHˆ6.7 Hz, 3H, CH3).
Compound 23: C34H42O5S (Mˆ562g mol 21); calcd: C
Compound 19: C29H43O5PS (Mˆ534 g mol21); HRMS (EI)
72.57, H 7.52, S 5.70, found: C 72.33, H 7.50, S 5.66; mp
1
calcd: 534.3569, found: 534.3570; H NMR (d, CDCl3):
1
2438C; H NMR (d, CDCl3): 7.85 (d, JHHˆ8.4 Hz, 2H,
7.85 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.63 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.64 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.49 (s, 4H,
C6H4), 7.44 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.22 (d,
C6H4), 7.47 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.32(dd,

1432
A. C. Freydank et al. / Tetrahedron 58 (2002) 1425±1432
JHHˆ16.5 Hz, 1H, vCH), 7.09 (d, JHHˆ16.5 Hz, 1H,
vCH), 7.07 (d, JHHˆ16.5 Hz, 1H, vCH), 6.96 (d, JHH
1H, vCH), 6.90 (d, JHHˆ8.4 Hz, 2H, C6H4), 6.12(broad s,
ˆ
1H, vCH2), 5.56 (broad s, 1H, vCH2), 4.32(t, JHH
4.8 Hz, 2H, OCH2), 4.14 (t, JHHˆ4.8 Hz, 2H, OCH2), 3.86
(t, JHHˆ4.8 Hz, 2H, OCH2), 3.81 (t, JHHˆ4.8 Hz, 2H,
OCH2), 3.01 (d, JHHˆ6.0 Hz, 2H, SO2CH2), 1.93 (s, 3H,
CH3), 1.89 (m, 1H, CH), 1.50±1.10 (m, 8H, CH2), 0.83
(m, 6H, CH3); 13C NMR (d, CDCl3): 167.3 (1C, CvO),
158.4, 142.6 (2C, i-C6H4), 138.1, 137.9 (2C, CHvCH),
136.0 (1C, CvCH2), 135.1, 132.0, 130.4, 128.7 (4C, i-
C6H4), 128.3, 127.7, 127.2, 126.8, 126.6 (10C, CH, C6H4),
126.0 (1C, CH2vC), 125.9, 125.8 (2C, CHvCH), 114.8
(2C, CH, C6H4), 69.6, 69.3, 67.4, 63.7 (4C, CH2±O), 59.9
(1C, CH2±SO2), 34.3 (1C, CH), 32.3, 28.1, 25.6, 22.6 (4C,
CH2), 18.3 (1C, CH3±CvCH2), 14.0, 10.1 (2C, CH3); IR
(CH2Cl2): 2962m, 2928m, 2866w, 2853w, 1717s (CvO),
1635s (CvC±O), 1591s (C6H4), 1514s (C6H4), 1299s
(SO2), 1246s (C±O), 1176s (C±O±C), 1142s (SO2), 1139s
ˆ
16.5 Hz, 1H, vCH), 6.91 (d, JHHˆ8.4 Hz, 2H, C6H4), 4.15
(t, JHHˆ4.8 Hz, 2H, OCH2), 3.87 (t, JHHˆ4.8 Hz, 2H,
OCH2), 3.74 (t, JHHˆ4.8 Hz, 2H, OCH2), 3.67 (t,
JHHˆ4.8 Hz, 2H, OCH2), 3.01 (d, JHHˆ6.0 Hz, 2H,
SO2CH2), 1.91 (m, 1H, CH), 1.50±1.12(m, 8H, CH 2),
0.81 (m, 6H, CH3); 13C NMR (d, CDCl3): 158, 142.6 (2C,
i-C6H4), 138.8, 138.7 (2C, CHvCH), 135.2, 132.0, 130.2,
128.6 (4C, i-C6H4), 128.3, 127.8, 127.3, 126.8, 126.6 (10C,
CH, C6H4), 126.1, 126.0 (2C, CHvCH), 114.8 (2C, CH,
C6H4), 72.6 (1C, CH2±OH), 69.6, 67.4, 61.7 (3C, CH2±
O), 59.9 (1C, CH2±SO2), 34.3 (1C, CH), 32.3, 28.1, 25.7,
22.6 (4C, CH2), 14.0, 10.1 (2C, CH3); IR (CH2Cl2): 3687w
(O±H), 3598w (O±H), 2967s, 2931s, 2874m, 1592m,
1514s, 1305s (SO2), 1248s (C±O), 1170m (C±O±C),
1143s (SO2), 1138s (C±O±C), 966m, 834m cm21
.
(C±O±C), 965m (CvC conjug.), 836 (1,4-C6H4) cm21
.
4.1.12. 2-Methyl-2-propenoic acid 2-{2-{4-{2-{4-{2-[4-
(decylsulfonyl)phenyl]ethenyl}phenyl}ethenyl}phenoxy}-
ethoxy}ethyl ester 24 and 2-methyl-2-propenoic acid 2-
{2-{4-{2-{4-{2-[4-(2-ethylhexylsulfonyl)phenyl]ethenyl}-
phenyl}ethenyl}phenoxy}ethoxy}ethyl ester 25. Freshly
distilled methacrylic anhydride (0.075 g, 0.49 mmol), 22
(0.23 g, 0.39 mmol) and 3-tert-butyl-4-hydroxy-5-methyl-
phenyl sul®de (0.015 g, 0.0419 mmol) were dissolved in
60 mL anhydrous 1,2-dichlorobenzene. Triethylamine
(0.49 g, 4.8 mmol) and a catalytic amount of N,N-dimethyl-
aminopyridine (DMAP, 0.0062g, 0.049 mmol) in 40 mL
1,2-dichlorobenzene were slowly added at room tempera-
ture. The reaction mixture was stirred for 12h at room
temperature, extracted three times with water and dried
over MgSO4 and the solvent was evaporated. The solid
was washed with diethyl ether and dried, to give 24 in
46% yield as a yellow-green solid. Similar reaction with
23 (1.16 g, 1.84 mmol) in CH2Cl2, and precipitation from
a CH2Cl2 solution with petrol afforded 25 in 58% yield as a
yellow-green solid.
Acknowledgements
We thank Dr Tom Wydryzynski for access to an SLM-
Aminco 8100 Spectro¯uorometer and Dr Nigel Lucas for
his helpful comments. M. G. H. thanks the Australian
Research Council for an ARC Australian Senior Research
Fellowship.
References
1. Luther-Davies, B.; Samoc, M. Curr. Opin. Solid State Mater.
Sci. 1997, 2, 213±219.
2. Burroughes, J.; Bradley, D. D. C.; Brown, A. R.; Marks, R. N.;
Mackay, K.; Friend, R. H.; Burns, P. L.; Holmes, A. B. Nature
1990, 347, 539±541.
3. Hide, F.; Diaz-Garcia, M. A.; Schwartz, B. J.; Heeger, A. I.
Acc. Chem. Res. 1997, 30, 430±436.
4. Robello, D. R. J. Polym. Sci., Part A: Polym. Chem. 1990, 28,
1±13.
Compound 24: C40H50O6S (Mˆ658 g mol21); calcd: C
5. Barashkov, N. N.; Guerrero, D. J.; Olivos, H. J.; Ferrais, J. P.
Synth. Met. 1995, 75, 153±160.
72.95, H 7.60, S 4.86, found: C 72.66, H 7.45, S 4.71; mp
1
1988C; H NMR (d, CDCl3): 7.84 (d, JHHˆ8.4 Hz, 2H,
6. Samoc, M.; Samoc, A.; Luther-Davies, B.; Bao, Z.; Yu, L.;
Hsieh, B.; Scherf, U. J. Opt. Soc. Am. B 1998, 15, 817±825.
7. Samoc, A.; Samoc, M.; Woodruff, M.; Luther-Davies, B. Opt.
Lett. 1995, 20, 1241±1243.
C6H4), 7.64 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.50 (s, 4H,
C6H4), 7.45 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.23 (d,
JHHˆ16.3 Hz, 1H, vCH), 7.10 (d, JHHˆ16.3 Hz, 1H,
vCH), 7.08 (d, JHHˆ16.3 Hz, 1H, vCH), 6.95 (d,
JHHˆ16.3 Hz, 1H, vCH), 6.90 (d, JHHˆ8.4 Hz, 2H,
C6H4), 6.12(broad s, 1H, vCH2), 5.56 (broad s, 1H,
vCH2), 4.15 (t, JHHˆ4.8 Hz, 2H, OCH2), 3.87 (t,
JHHˆ4.8 Hz, 2H, OCH2), 3.77 (t, JHHˆ4.8 Hz, 2H, OCH2),
3.67 (t, JHHˆ4.8 Hz, 2H, OCH2), 3.07 (t, JHHˆ6.0 Hz, 2H,
SO2CH2), 1.93 (s, 3H, CH3), 1.69 (m, 2H, CH2), 1.24 (m,
14H, CH2), 0.86 (t, JHHˆ6.7 Hz, 3H, CH3).
8. Bubeck, C. Organic Thin Film for Waveguiding Nonlinear
Optics; Gordon and Breach: Amsterdam, The Netherlands,
1996.
9. Detert, H.; Sugiono, E. Synth. Met. 2000, 115, 89±92.
10. Davis, W. B.; Wasielewski, M. R.; Ratner, M. A. Int. J. Quant.
Chem. 1999, 72, 463±471.
11. Cornil, J.; Beljonne, D.; Friend, R. H.; Bredas, J. L. Chem.
Phys. Lett. 1994, 223, 82±88.
12. Wong, M. S.; Samoc, M.; Samoc, A.; Luther-Davies, B.;
Humphrey, M. G. J. Mater. Chem. 1998, 8, 2005±2009.
13. Wiley, G. A.; Hershkowitz, R. L.; Rein, B. M.; Chung, B. C.
J. Am. Chem. Soc. 1964, 86, 964±965.
Compound 25: C38H46O6S (Mˆ646 g mol21); calcd: C
72.38, H 7.30, S 5.08, found: C 72.31, H 7.33, S 4.99; mp
1
1798C; H NMR (d, CDCl3): 7.86 (d, JHHˆ8.4 Hz, 2H,
C6H4), 7.64 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.50 (s, 4H,
14. Freydank, A. C.; Humphrey, M. G.; Samoc, A.; Samoc, M.;
Luther-Davies, B. In preparation.
15. Duranti, E. N. Synth. Commun. 1999, 29, 4201±4222.
C6H4), 7.43 (d, JHHˆ8.4 Hz, 2H, C6H4), 7.12(d, JHH
ˆ
16.4 Hz, 1H, vCH), 7.10 (d, JHHˆ16.4 Hz, 1H, vCH),
7.09 (d, JHHˆ16.4 Hz, 1H, vCH), 6.95 (d, JHHˆ16.4 Hz,