Highly Emissive Supramolecular Oligo(p-phenylene vinylene) Dendrimers

Article abstract of DOI:10.1021/ja0211050

π-Conjugated oligo(p-phenylene vinylene) (OPV) guest molecules for interaction with dendritic hosts were synthesized and fully characterized by NMR spectroscopy, MALDI-TOF-MS, elemental analysis and optical measurements. The binding properties of the five

Full text of DOI:10.1021/ja0211050

Published on Web 09/27/2003
Highly Emissive Supramolecular Oligo(p-phenylene vinylene)
Dendrimers
F. S. Precup-Blaga,† J. C. Garcia-Martinez,‡ A. P. H. J. Schenning,*,† and
E. W. Meijer*,†
Contribution from the Laboratory for Macromolecular and Organic Chemistry, EindhoVen
UniVersity of Technology, P.O. Box 513, 5600 MB EindhoVen, The Netherlands, and Facultad
de Qu´ımica, UniVersidad de Castilla-La Mancha, 13071- Ciudad Real, Spain
Received August 21, 2002; Revised Manuscript Received May 20, 2003
Abstract: π-Conjugated oligo(p-phenylene vinylene) (OPV) guest molecules for interaction with dendritic
hosts were synthesized and fully characterized by NMR spectroscopy, MALDI-TOF-MS, elemental analysis
and optical measurements. The binding properties of the five different OPV guests to aN,N-bis[(3-adamantyl
ureido) propyl] methylamine host have been investigated. The guests that contained an aryl urea glycine
spacer were bound with the highest association constant. Subsequently, an adamantyl urea modified fifth
generation poly(propylene imine) dendrimer was synthesized as a multivalent host which contains 32 N,N-
bis[(3-adamantyl ureido) propyl] amine binding sites. Size exclusion chromatography showed that 32 of
the OPV guests strongly bind to the fifth generation adamantyl functionalized dendritic host. In the case of
the supramolecular dendritic host/guest system smooth homogeneous thin films could be obtained by spin
coating. The dendritic guest-host complexes showed a significantly higher emission upon binding then
that of the individual molecules due to the three-dimensional orientation of the OPV guest molecules. In
the solid state, this enhancement in luminescence was a factor of 10. The π-conjugated oligomers are less
aggregated in the supramolecular assemblies presumably because of a shielding effect of the bulky
adamantyl units present in the hosts.
Introduction
ylene vinylene)s (OPVs) have been oriented in a tetrahedral
framework minimizing intramolecular stacking.6 These tetra-
hedral arrays do not crystallize and form stable amorphous
phases.
After the first report on electroluminescence in poly(p-
phenylene vinylene) (PPV),1 a variety of π-conjugated polymers
and oligomers have been synthesized and applied in light
emitting diodes (LEDs).2 An impressive number of research
groups have expended considerable effort in attempting to
improve the performance of these materials.3,4
Aggregation of π-conjugated materials (especially H-type
aggregates) is often observed resulting in low quantum efficien-
cies of luminescence.5 Branching of π-conjugated systems can
overcome this stacking phenomenon, for example, oligo(p-phen-
Another route to obtain branched systems is the use of
dendrimers. These macromolecules possess a covalent three-
dimensional structure that permits spatial control of the active
components and thus the electroluminescent properties.7 Fur-
thermore, the durability of LEDs can be enhanced by prevention
of crystallization of the active component, leading to truly
amorphous films. This is important because crystallization or
melting, caused by heat or short-circuit currents, often results
in device damage.8 Dendrimers can be designed so that the core
defines the color of the light emission, whereas the surface
groups control the processing properties and the branching units
act as charge transporting units.9 An important feature of
incorporating chromophores as cores is that it provides the
chromophores in a solution processible form, and reducing
† Laboratory for Macromolecular and Organic Chemistry, Eindhoven
University of Technology.
‡ Facultad de Qu´ımica, Universidad de Castilla-La Mancha.
(1) Burroughes, J. H.; Bradley, D. D. C.; Brown, A. R.; Marks, R. N.; Mackay,
K.; Friend, R. H.; Burn, P. L.; Holmes, A. B. Nature 1990, 347, 539. (b)
Braun, D.; Heeger, A. J. Appl. Phys. Lett. 1991, 58, 1982. (c) Bradley, D.
D. C. AdV. Mater., 1992, 4, 756.
(2) Kraft, A.; Grimsdale, A. C. Holmes, A. B. Angew. Chem. Int. Ed. Engl.
1998, 37, 402.
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R. E.; Malliaras, G. G.; Wildeman, J.; Hadziioannou, G. AdV. Mater. 1994,
6, 132. (c) Burn, P. L.; Holmes, A. B.; Kraft, A.; Bradley, D. D. C.; Brown,
A. R.; Friend, R. H.; Gymer, R. W. Nature 1992, 356, 47. (d) Burn, P. L.;
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Gymer, R. W.; Holmes, A. B.; Jackson, R. W. J. Am. Chem. Soc. 1993,
115, 10 117. (e) Hay, M.; Klavetter, F. L. J. Am. Chem. Soc. 1995, 117,
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1996, 8, 507.
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A. B. Nature 1993, 365, 628.
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A R T I C L E S
Precup-Blaga et al.
Scheme 1. Concept of Supramolecular Anchoring of OPV Guest
to a Dendritic Host
vinylene) guests that bind to adamantyl urea modified dendritic
hosts (Scheme 1). The resulting supramolecular assemblies are
investigated with respect to their photophysical properties.
Recently, Holmes, Kraft and co-workers described the
preparation of stilbene-carboxylic acids that form noncovalent
complexes with tris(imidazoline) base derivatives.17 These
supramolecular complexes showed strong fluorescence in solu-
tion whereas in the solid-state photoluminescence was quenched.
Results and Discussion
Synthesis. The π-conjugated guests (OPV1, OPV2, OPV3,
OPV4, OPV5, Scheme 2) are rationally designed and consist
of a carboxylic acid and an urea moiety. OPV1 and OPV2 were
synthesized from activated ester derivative 1.12 Reaction of 1
with tert-butyl N-(6-aminohexyl)carbamate hydrochloride yielded
compound 2 which was deprotected to give amine 3. After
reaction with, respectively, ethyl isocyanatoacetate and ethyl
3-isocyanatopropionate and subsequent hydrolysis, OPV1 and
OPV2 were obtained. OPV3 and OPV4 were synthesized from
nitro derivative 7 that was formed in a Wittig-Horner reaction
of diethyl(4-nitrobenzyl)phosphonate and aldehyde compound
6.18 Subsequent reduction of the nitro group yielded amine 8.
After reaction with ethyl isocyanatoacetate and ethyl 3-isocy-
anatopropionate and subsequent hydrolysis OPV3 and OPV4
were obtained, respectively. OPV5 was prepared from isocy-
anate derivative 1119 after subsequent reaction with glycine
methyl ester hydrochloride and hydrolysis. All five OPV guests
were fully characterized including NMR spectroscopy, MALDI-
TOF-MS and elemental analysis.
Binding Studies. The binding properties of OPV guests were
first tested with N,N-bis[(3-adamantylureido)propyl]methy-
lamine (Pincer, Figure 1a), which is the binding moiety in the
fifth generation poly(propylene imine) dendrimer functionalized
with urea adamantyl units at the periphery (Dendr, Figure 1b).13
All pincer-guest complexes show fast exchange between the
bound and free states on NMR time scale. For example treatment
of Pincer with OPV-guest OPV5 in CDCl3 resulted in char-
acteristic changes (Figure 1) of both NH protons of the guest
OPV5 (δ ) 7.53 to 8.45; and δ ) 5.85 to 7.0-7.6), as well as
the urea hydrogen signal of the pincer (δ ) 5.75 to 6.57),
indicating the formation of a hydrogen-bonded complex Pincer‚
OPV5. The urea NH resonances of Pincer as well as for the
guests show a downfield shift for all the guests used, being in
full agreement with the previous results.13
aggregation.10 Moreover, light harversting and site-isolation of
the chromophores is achieved.11
We have functionalized poly(propylene imine) dendrimers
up to generation five with π-conjugated oligo(p-phenylene
vinylene)s (OPVs).12 These dendrimers proved to be good hosts
for anionic dye molecules. Thin films prepared from these host-
guest complexes showed efficient (>90%) energy transfer from
the OPV units to the encapsulated dye molecules. By choosing
the appropriate dye, the emission wavelength could be tuned.
Preliminary experiments showed that it was possible to construct
LEDs from the dye/dendrimer system, athough aggregation and,
hence quenching of the luminescence was still observed even
for the fifth generation dendrimer.
Recently, we published a supramolecular strategy for modify-
ing the periphery of the poly(propylene imine) dendrimer
(Scheme 1).13,14 Adamantyl-urea modified dendrimers were used
as a scaffold to reversibly bind glycine-urea funtionalized guests
in organic media using hydrogen bond (between the urea
linkages of dendrimer and the guest) and acid-base interactions
(between COOH of the guest and amines of the host). We have
also found that adamantyl dendrimers, noncovalently function-
alized with catalytic sites, can be applied in a continuous flow
membrane reactor. This system does not show leaching of the
catalytic sites.15
Adamantyl dendrimers are known to adopt a persistent
globular conformation similar to the dendritic box,16 due to the
three-dimensional dendritic scaffolding, resulting in the forma-
tion of amorphous films. Moreover, the existence of bulky and
rigid adamantyl groups at the periphery of dendrimer reduces
intermolecular distances, preventing aggregation.
Here, we report the design, synthesis, and optical properties
of glycinyl-urea functionalized π-conjugated oligo(p-phenylene
The binding constants were determined by following the urea
hydrogen resonances of the Pincer. The guest molecules were
bound as 1:1 inclusion complexes and the association constants
are listed in Table 1. Although the differences in binding strength
are relatively small, there are some significant trends. Increasing
the spacer between the ureido and acid group (from methylene
to ethylene) leads to a lowering of the association constant
(Pincer‚OPV1 versus Pincer‚OPV2 and Pincer‚OPV3 versus
Pincer‚OPV4). Introduction of an aliphatic spacer induced a
decrease in binding strength (Pincer‚OPV3 and Pincer‚OPV4
versus Pincer‚OPV1 and Pincer‚OPV2). A decrease in as-
(10) Halim, M.; Samuel, I. D. W.; Pillow, J. N. G.; Burn. P. L. Synth. Met.
1999, 102, 1113. (b) Halim, M.; Samuel, I. D. W.; Pillow, J. N. G.;
Monkman, A. P.; Burn. P. L. Synth. Met. 1999, 102, 1571. (c) Freeman,
A. W.; Koene, S. C.; Malenfant, P. R. L.; Thompson, M. E.; Fre´chet J. M.
J. J. Am. Chem. Soc. 2000, 122, 12385. (d) Lupton, J. M.; Hemingway, L.
R.; Samuel, I. D. W.; Burn. P. L. J. Mater. Chem. 2000, 10, 867. (e) Weil,
T.; Reuther, E.; Mu¨llen, K. Angew. Chem., Int. Ed. 2002, 41, 1900.
(11) Adronov, A.; Fre´chet, J. M. J. Chem. Commun. 2000, 1701.
(12) Schenning, A. P. H. J.; Peeters, E.; Meijer. E. W. J. Am. Chem. Soc. 2000,
122, 4489.
(13) Baars, M. W. P. L.; Karlsson, A. J.; Sorokin, V.; de Waal, B.; Meijer, E.
W. Angew. Chem., Int. Ed. Engl. 2000, 39, 4262.
(14) Boas, U.; Karlsson, A. J.; de Waal, B. F. M.; Meijer, E. W. J. Org. Chem.
2001, 66, 2136.
(15) de Groot, D.; de Waal, B. F. M.; Reek, J. N. H.; Schenning, A. P. H. J.;
Kamer, P. C. J.; Meijer, E. W.; Leeuwen, P. W. N. M. J. Am. Chem. Soc.
2001, 123, 8453.
(16) van Genderen, M. H. P.; de Brabander-van den Berg, E. M. M.; Meijer, E.
W. AdVances in Dendritic Macromolecules, 1999, 4, 61. (b) Stevelmans,
S.; van Hest, J. C. M.; Jansen, J. F. G. A.; van Boxtel, D. A. F. J.; de
Brabander-van den Berg, E. M. M.; Meijer, E. W. J. Am. Chem. Soc. 1996,
118, 7398.
(17) Osterod, F.; Peters, L.; Kraft A.; Sano, T. Morrison, J. J.; Feeder, N.;
Holmes, A. B. J. Mater. Chem. 2001, 11, 1625.
(18) Peeters, E.; van Hal, P. A.; Knol, J.; Brabec, C. J.; Sariciftci, N. S.;
Hummelen, J. C.; Janssen, R. A. J. J. Phys. Chem. B 2000, 104, 10174.
(19) Peeters, E.; van Hal, P. A.; Meskers, S. C. J.; Janssen, R. A. J.; Meijer, E.
W. Chem. Eur. J. 2002, 8, 4470. (b) Syamakumari, A.; Schenning, A. P.
H. J.; Meijer, E. W. Chem. Eur. J. 2002, 8, 3353.
9
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A R T I C L E S
Scheme 2
Reagents and conditions: (a) tert-butyl N-(6-aminohexyl)carbamate hydrochloride, NEt3, rt; (b) TsOH in toluene, reflux, 2 h; (c) ethyl isocyanate acetate,
rt, 30 min; (d) ethyl 3-isocyanateproprionate, 0 °C; (e, f, k, l, n) LiOH‚H2O, THF, rt; (g) diethyl(4-nitro benzyl) phosphonate, DMF, KtBuO, rt, 4h; (h)
SnCl2‚2H2O, EtOH/EtOAc, 75 °C, 5h; (i) ethyl isocyanate acetate, rt, 30 min; (j) ethyl 3-isocyanateproprionate, 0 °C; (m) Et3N, glycine methyl ester
hydrochloride, rt.
sociation constant of a factor of 2 is observed by comparing
the association constant of complexes Pincer‚OPV3 with
Pincer‚OPV5.20
The properties of OPV3 and OPV5 were further investigated
with fifth generation adamantyl functionalized propylene den-
drimer Dendr, because these guests showed the highest as-
sociation constant with the Pincer host. In the 1H NMR
spectrum the urea-protons of the dendritic scaffold show a
downfield shift for both guests, indicating binding at the
periphery of the host. In both cases, a maximum of 32 guests
were bound and this stoichiometry is preserved after repeated
preparative size exclusion chromatography.21 To confirm the
complexation and location between host and guest, NOE
(20) A reasonable explanation for the differences in binding strength is difficult
to give because of the many variables in the guest molecules. Moreover,
some of the guests show self-association.
(21) We tried to determine the binding constant by microcalometry, but no
reliable data were obtained for number of binding sites, see also ref 13.
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Figure 1. 1H NMR of (a) OPV5, Pincer‚OPV5, and Pincer; (b) Dendr‚(OPV5)32.
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A R T I C L E S
Table 1. Association Constants of the Different OPV-Guests with Pincer
complex
Ka (M-1
CIS (ppm)a
Pincer ‚OPV1
Pincer ‚OPV2
Pincer ‚OPV3
Pincer ‚OPV4
Pincer ‚OPV5
)
(1.2 ( 0.3) × 103
(0.3 ( 0.1) × 103
(12.9 ( 3.1) × 103
(2.7 ( 1.1) × 103
(6.6 ( 1.3) × 103
1.5 ( 0.2
1.3 ( 0.2
1.0 ( 0.1
1.2 ( 0.1
0.8 ( 0.1
a CIS values of the urea hydrogen resonances of the pincer
Table 2. Absorption and Fluorescence Maxima of the Guests and
Host-Guest Complexes in Solution and in Thin Film
fluorescence λmax,em (nm)
UV−vis λmax(nm)
thin film
solution
thin film
solution
thin film
PL efficiency
OPV3
Dendr‚(OPV3)32
OPV5
Dendr‚(OPV5)32
Pincer ‚OPV5
402
402
434
432
429
390
395
405
423
416
470
470
500
500
500
510
511
550
552
552
4%
37%
2%
12%
19%
experiments were performed in CDCl3. Due to the overlap of
signals in 1H NMR spectrum of the complex Dendr‚(OPV3)32
in CDCl3, the solution structure of the complex was further
investigated with the fifth generation adamantyl-functionalized
dendrimer having amide linkages.13 The 1H-1H NOESY
spectrum of the complex showed NOE interactions between the
CH2 protons next to the urea group of the guest and the middle
CH2 of the outermost shell of the dendritic host, similar as
observed previously.13 These results reveal that the guest
molecules are located at the periphery of the dendrimers.
Optical Studies. The optical properties of guests OPV3,
OPV5, and the host-guest complexes Pincer‚OPV5, Dendr‚
(OPV3)32, and Dendr‚(OPV5)32 were investigated by UV-vis
and fluorescence spectroscopy. The absorption maximum of
Figure 2. UV-vis (left) and fluorescence (right) spectrum of OPV3 (2.16
× 10-6 M) and Dendr‚(OPV3)32 (6.75 × 10-8 M).
rough surface with a typical roughness of >50 nm. In the case
of the dendritic host-guest systems, a homogeneous surface
was obtained (a roughness of < 10 nm for surfaces on 20 µm
scale), whereas in the case of the pincer as host an inhomoge-
neous film was observed even on a scale less than 5 µm.
The films show a hypsochromic shift of the absorption
maximum when comparing with the solution spectra (for
example OPV5: ∆λmax ) 29 nm, Pincer‚OPV5: ∆λmax ) 13
nm, Dendr‚(OPV5)32: ∆λmax ) 9 nm) indicating aggregation
of the π-systems (Table 2). This blue shift is larger in the free
guest than in the case of the host-guest systems. Presumably,
the bulky adamantyl units prevent the OPV units from π-π
stacking. Fluorescence spectra of these films show an emission
at λmax,em ) 510 nm for the OPV trimers and λmax,em ) 552 nm
for the OPV tetramers. The thin film of host-guest complexes
show brilliant yellow fluorescence while in the case of the guest
itself the fluorescence is highly quenched. To quantify this
observation, external quantum efficiencies of the films were
measured using an integrated sphere (Table 2).23 In the case of
host-guest systems, the PL efficiencies are a factor of 10 higher.
There is almost no difference between the pincer and dendritic
host which illustrates that the high emission is the result of the
bulky adamantly unit sealing the chromophores from aggrega-
tion. The supramolecular approach shows clearly that chro-
mophores can be isolated in the solid state, whereas dendritic
hosts give rise to films of good quality.
OPV3 and OPV5 (illustrated in Table 2) is located at λmax
)
402 nm and λmax ) 434 nm respectively, and can be attributed
to the π-π* transition of an OPV trimer and tetramer.22 The
UV-vis spectrum of Pincer‚OPV5 shows an absorption
maximum at λmax ) 429 nm, whereas the dendritic complexes
show a absorption maximum at λmax ) 402 and 432 nm,
respectively. Fluorescence measurements show an emission
maximum at λmax,em ) 470 nm for both OPV3 and Dendr‚
(OPV3)32 and λmax,em ) 500 nm for OPV5, Pincer‚OPV5 and
Dendr‚(OPV5)32; values typical for OPV trimers and OPV
tetramers. Interestingly, an increase in the intensity of the
emission for the bound guest was observed: 3.3 times for
Dendr‚(OPV3)32 and 2 times for Dendr‚(OPV5)32 (Figure 2).
This behavior indicates that the guest molecules are not
completely molecularly dissolved in solution. When no host is
present, weak interactions between the π-conjugated oligomers
are presumably present, and therefore, the fluorescence is
slightly quenched. In the supramolecular complexes such
interactions do not exist due to the bulky adamantyl groups.
In the case of the dendritic host-guest complexes (Dendr‚
(OPV3)32 and Dendr‚(OPV5)32) we obtained good quality thin
films by spin coating from a toluene solution. The supramo-
lecular system based on the pincer as host (Pincer‚OPV5)
showed an inhomogeneous yellow film indicating domain
formation. Poor quality films were obtained in the case of the
guest molecules alone. Tapping-mode atomic force micrcoscopy
(AFM) confirmed this behavior, e.g. pure OPV5 revealed a
Conclusions
In conclusion, we have studied the binding and optical
properties of π-conjugated guests to N, N-bis[(3-adamantyl
ureido) propyl] methylamine, and to a adamantyl urea modified
fifth generation poly(propylene imine) dendritic hosts that
contain 32 of these binding sites. Guests consisting of urea
glycine moiety are bound most strongly. The reversible nature
of this binding opens the way toward dynamic multicomponent
assemblies that are of interest for electron and energy transfer
reactions.
(22) Peeters, E.; Janssen, R. A. J.; Meskers, S. C. J.; Meijer, E. W. Polymer
Preprint. 1999, 40, 519.
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°C. IR (UATR) v 3366, 2959, 2930, 2874, 1687, 1633, 1603, 1507,
Furthermore, we have demonstrated that the conjugated guests
show improved emission upon binding. In the solid state this
enhancement is 10 times higher than the guest itself. The
π-conjugated oligomers are most likely less aggregated in the
supramolecular assemblies because of shielding effect of the
bulky adamantyl units present in the host. In the case of the
dendrimer system, smooth homogeneous thin films could be
obtained by spin coating. It shows that the dendritic host/guest
complexes are the most promising ones in applying this
supramolecular concept in LEDs and work along this line is in
progress.
1
1464, 1414, 1389, 1342, 1249, 1201, 1173, 1043, 965, 851 cm-1. H
NMR (CDCl3): δ 0.9-1.1 (m, 36H), 1.3-2.0 (m, 26H), 1.44 (s, 9H),
2.24 (s, 3H), 3.11 (dt, br, 2H), 3.46 (dt, br, 2H) 3.74-4.04 (m, 12H),
4.54 (s, 1H), 6.73 (s, 1H), 7.10 (s, 1H), 7.17 (s, 1H), 7.19 (s, 1H), 7.21
(s, 1H), 7.45 (d, 1H), 7.49 (d, 1H,), 7.51 (d, 1H), 7.57 (d, 1H), 7.77 (s,
1H), 8.15 (t, br, 1H). 13C NMR (CDCl3): δ 11.28, 11.36, 11.43, 11.46,
16.4, 16.69, 16.73, 16.79, 16.82, 26.24, 26.33, 26.35, 26.51, 26.81,
28.37, 28.40, 29.62, 30.02, 34.93, 34.95, 35.03, 39.68, 40.50, 73.37,
74.00, 74.10, 74.22, 74.28, 74.64, 108.37, 109.54, 109.82, 110.26,
115.63, 116.27, 120.68, 121.58, 121.85, 123.37, 124.97, 125.07, 126.42,
127.70, 128.26, 131.12, 150.47, 150.75, 150.92, 151.24, 151.67, 155.96,
165.13. UV-vis (CH2Cl2): 419 (49000), 322 (20000). MALDI-TOF-
MS (MW ) 1055.53) m/z ) 1055.48.
1
Experimental. General Methods. H NMR and 13C NMR spectra
were recorded at room temperature on a Varian Gemini 300 or 400
MHz spectrometer in deuterated chloroform and tetramethylsilane
(TMS) was used as internal reference. Abbreviations used are s )
singlet, d ) doublet, t ) triplet, m ) multiplet, and b ) broad.
Preparative size exclusion chromatography was carried out with
Biobeads S-X1 Beads (200-400 mesh) with a cutoff of 14 kD, and
were obtained from Bio-Rad Laboratories; dichloromethane was used
as eluent. Elemental analysis were performed on a Perkin-Elmer, Series
(E,E)-N-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-2-methyl butoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]benzoyl}-
hexyldiamine (3). Compound 2 (700 mg 0.66 mmol) and p-tolunene-
sulfonic acid (506 mg 2.6 mmol) were dissolved in toluene (50 mL)
and heated to reflux for 2 h. The solution was cooled, concentrated,
dissolved in chloroform, and washed with a K2CO3 saturated solution.
The organic layer was dried, filtered and concentrated. After crystal-
lization from heptane 3 (590 mg, 93%) was obtained as a yellow solid.
Mp: 111 °C. IR (UATR) v 3403, 2961, 2928, 2875, 1655, 1602, 1501,
1
1
II, 2400. The 2D NMR H, H NOESY experiments were carried out
on a Varian Inova 500 spectrometer operating at 500.618 MHz and
equipped with a 5 mm 500 SW/PFG probe. The spectra were obtained
at 25 °C. The 2D NMR spectra were acquired using nonspinning 5
1
1464, 1415, 1386, 1201, 1042, 774 cm-1. H NMR (CDCl3): δ 0.9-
1.1 (m, 36H), 1.3-2.0 (m, 26H), 2.24 (s, 3H), 2.72 (s, 2H), 3.46 (dt,
br, 2H), 3.74-4.04 (m, 14H), 6.73 (s, 1H), 7.10 (s, 1H), 7.17 (s, 1H),
7.19 (s, 1H), 7.21 (s, 1H), 7.45 (d, 1H), 7.49 (d, 1H), 7.51 (d, 1H),
7.57 (d, H), 7.77 (s, 1H), 8.15 (t, br, 1H). 13C NMR (CDCl3): δ 11.28,
11.35, 11.42, 11.45, 16.40, 16.68, 16.73, 16.78, 16.81, 26.24, 26.32,
26.34, 26.53, 26.93, 29.62, 33.05, 34.93, 34.94, 35.03, 35.09, 39.70,
41.86, 73.36, 74.00, 74.10, 74.22, 74.28, 74.64, 108.36, 109.53, 109.81,
110.25, 115.62, 116.27, 120.68, 121.57, 121.84, 123.36, 124.96, 125.07,
126.42, 127.69, 128.25, 131.11, 150.46, 150.74, 150.92, 151.24, 151.67,
165.12. UV-vis (CH2Cl2): 419 (33000), 320 (24000). MALDI-TOF-
MS (MW ) 955.41) m/z)955.54.
1
1
mm samples with deuterium field-frequency locking. For the H, H
NOESY spectra, the following parameters were used: spectral width,
5086 Hz (f2) and 5086 Hz (f1); 256 increments and 16 scans per
increment in t1; calibrating mixing time 0.1 s. The concentrations of
the host-guest complexes were kept constant at 0.4 mM. The constancy
of the equilibrium signal intensity was always investigated over the
whole d2-array period.
Determination of the association constants (Ka) was carried out under
Benesi-Hildebrand conditions at 25 °C in CDCl3.24 The concentration
of the host was kept constant (1 mM), whereas the guests’ concentra-
tions were varying in the range 0.1-2 mM.
(E,E)-6-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-2-methyl butoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]benzoy-
lamino}-hexyl ureido-acetic acid ethyl ester (4). To a CHCl3 solution
(5 mL) of 3 (153 mg 0.16 mmol) was added ethyl isocyanateacetate
(51 mg 0.39 mmol) in CHCl3 (2 mL). After 30 min, the solvent was
evaporated, toluene was added and evaporated several times to remove
the excess of isocyanate. After crystallization from heptane 4 was
obtained as a yellow solid (173 mg, 100%). Mp: 125 °C. IR (UATR)
v 3346, 3058, 2959, 2928, 2859, 1748, 1687, 1636, 1603, 1592, 1538,
1507, 1464, 1414, 1389, 1375, 1343, 1251, 1200, 1113, 1043, 966,
852 cm-1. 1H NMR (CDCl3): δ 0.9-1.11 (m, 36H), 1.25-2.0 (m, 26H),
1.27 (t, 3H), 2.24 (s, 3H), 3.19 (dt, br, 2H), 3.48 (dt, br, 2H), 3.74-
4.04 (m, 14H), 4.19 (q, 2H), 5.16 (t, br., 1H), 5.36 (t, br., 1H), 6.73 (s,
1H), 7.10 (s, 1H), 7.17 (s, 1H), 7.19 (s, 1H), 7.21 (s, 1H), 7.44 (d,
1H), 7.48 (d, 1H), 7.52 (d, 1H), 7.58 (d, 1H), 7.76 (s, 1H), 8.20 (t, br,
1H). 13C NMR (CDCl3): δ 11.29, 11.36, 11.45, 14.14, 16.40, 16.69,
16.73, 16.82, 25.86, 26.09, 26.26, 26.33, 29.56, 34.94, 35.04, 35.09,
39.21, 40.07, 42.25, 61.21, 73.40, 74.01, 74.11, 74.24, 74.30, 74.66,
108.42, 109.59, 109.84, 110.28, 115.94, 116.29, 120.56, 121.60, 121.82,
123.42, 125.10, 126.41, 127.73, 128.32, 131.28, 150.49, 150.80, 150.95,
151.27, 151.69, 157.88, 165.40, 171.23. UV-vis (CH2Cl2): 420
(43000), 323 (18000). MALDI-TOF-MS (MW ) 1084.53) m/z )
1084.61. Anal.Calcd. for C65H101N3O10: C 71.99, H 9.39, N 3.87.
Found: C 71.09, H 9.26, N 3.84.
UV-vis spectra and fluorescence spectra were recorded on a Perkin-
Elmer Lambda 40 Spectrometer and a Perkin-Elmer luminescence
spectrometer LS 50 B instrument. Melting points were determined with
a Buchi B-450 Melting point apparatus. Infrared spectra were recorded
on a Perkin-Elmer Spectrum one with a ATR sampling accessory.
Matrix assisted laser desorption ionization time-of-flight (MALDI-TOF)
mass spectrometry were measured on a Perspective Biosystems
Voyager- DE PRO instrument in reflector mode, using R-cyano-4-
hydroxy-cinnamic acid as the matrix. Spin-coated thin films were
prepared by spin-casting from THF solutions using a Headway Research
Spin-coat apparatus. For measuring thin-film PL quantum efficiency
an integrating sphere was used.23
Atomic Force Microscopy measurements were carried out at room
temperature with an AFM (Digital Instruments) equipped with a
Nanoscope IIIa controller (Digital Instruments) in the Tapping Mode.
(E,E)-6-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-2-methylbutoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]-
benzoylamino}hexylcarbamic acid t-butyl ester (2). To a CH2Cl2
suspension (10 mL) of tert-butyl N-(6-aminohexyl)carbamate hydro-
chloride (378 mg 1.5 mmol) and triethyamine (151 mg 1.5 mmol) was
added (E,E)-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-bis-
[(S)-2-methylbutoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]benzoic acid
pentafluoro- phenyl ester (1)12 (900 mg 0.88 mmol) in CH2Cl2. After
half hour the mixture was washed with a saturated K2CO3 solution.
The organic layer was dried, filtered, and concentrated. After crystal-
lization from heptane pure 2 was obtained (927 mg, 100%). Mp: 144
(E,E)-3-[-6-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-
2,5-bis[(S)-2-methylbutoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]-
benzoylamino}hexylureido] propionic acid ethyl ester (5). To a
chloroform solution (5 mL) of 3 (153 mg 0.16 mmol) at 0°C was added
ethyl 3-isocyanatepropionate (51 mg 0.39 mmol in CHCl3 (2 mL). After
30 min HCl (1M) was added and the organic layer was further washed
(23) de Mello, J. C.; Wittmann, H. F.; Friend, R. H. AdV. Mater., 1997, 9, 230.
(24) Benesi, H. A.; Hildebrand, J. H. J. J. Am. Chem. Soc. 1949, 71, 1, 2703.
(b) Foster, R.; Fyfe, C. A. Prog. Nucl. Magn. Reson. Spectrosc. 1969, 4,
1.
9
12958 J. AM. CHEM. SOC. VOL. 125, NO. 42, 2003

Highly Emissive Supramolecular Dendrimers
A R T I C L E S
with brine, dried, filtrated and concentrated. After crystallization from
heptane (95 mg, 100%) 5 was obtained as a yellow solid. Mp: 136
°C. IR (UATR) v 3373, 2960, 2929, 2875, 1735, 1633, 1535, 1508,
(E,E)-3-[4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-methyl butoxy]styryl}phenyl]ureido acetic acid ethyl ester
(9). To a chloroform solution (5 mL) of 8 (124 mg 0.19 mmol) was
added ethyl isocyanatoacetate (65 mg 0.5 mmol) in CHCl3 (2 mL).
After 30 min the solvent was evaporated and toluene was added and
evaporated several times to remove the excess isocyanate. After
crystallization from heptane 9 (149 mg, 100%) was obtained as a yellow
solid. Mp: 126 °C. IR (UATR) v 3349, 3057, 2962, 2922, 2875, 1748,
1704, 1654, 1594, 1543, 1512, 1464, 1413, 1202, 1044 cm-1. 1H NMR
(CDCl3): δ 0.85-1.11 (m, 24H), 1.29 (t, 3H), 1.25-1.39 (m, 4H),
1.57-1.68 (m, 4H), 1.87-1.97 (m, 4H), 2.24 (s, 3H), 3.73-3.93 (m,
8H), 4.07 (d, 2H), 4.22 (q, 2H), 5.83 (s, br., 1H), 6.73 (s, 1H), 6.89 (s,
br., 1H), 7.08 (d, 1H), 7.09 (s, 1H), 7.10 (s, 1H), 7.17 (s, 1H), 7.34 (d,
2H), 7.40 (d, 1H), 7.44 (d, 1H), 7.45 (d, 2H), 7.5 (d, 1H). 13C NMR
(CDCl3): δ 11.36, 11.46, 11.50, 14.04, 14.13, 16.38, 16.69, 16.80,
16.85, 22.32, 26.26, 26.35, 34.11, 34.97, 35.12, 35.16, 42.16, 61.56,
73.39, 74.05, 74.53, 74.68, 108.33, 109.60, 110.84, 116.33, 121.40,
121.63, 122.86, 123.08, 125.186, 126.34, 127.35, 127.61, 127.68,
127.77, 134.20, 137.26, 150.46, 150.88, 151.26, 151.71, 155.43, 171.03.
UV-vis (CH2Cl2): 405 (34000), 321 (21000). MALDI-TOF-MS (MW
) 785.07) m/z ) 785.14.
(E,E)-3-{3-[4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-methyl butoxy]styryl}phenyl]ureido} propionic acid ethyl
ester (10). To a chloroform solution (5 mL) of 8 (186 mg 0.28 mmol)
at 0°C was added ethyl 3-isocyanatopropionate (47 mg 0.31 mmol) in
CHCl3 (2 mL). After 30 min HCl (1M) was added and the organic
layer washed with brine, dried, filtrated, and concentrated. After
crystallization from heptane 10 (210 mg, 75%) was obtained as a yellow
solid. Mp: 114 °C. IR (UATR) v 3318, 2959, 2922, 2874, 1731, 1643,
1588, 1555, 1509, 1462, 1412, 1375, 1341, 1309, 1239, 1200, 1043,
964, 851 cm-1. 1H NMR (CDCl3): δ 0.95-1.11 (m, 24H), 1.25 (t, 3H),
1.25-1.39 (m, 4H), 1.57-1.68 (m, 4H), 1.87-1.97 (m, 4H), 2.24 (s,
3H), 2.59 (t, 2H), 3.55 (dt, br., 2H), 3.73-3.94 (m, 8H), 4.14 (q, 2H),
5.59 (s, br., 1H), 6.73 (s, 1H), 6.89 (s, br., 1H), 7.09 (d, 1H), 7.10 (s,
1H), 7.14 (s, 1H), 7.18 (s, 1H), 7.31 (d, 2H), 7.41 (d, 1H), 7.44 (d,
1H), 7.45 (d, 2H), 7.51 (d, 1H). 13C NMR (CDCl3): δ 11.47, 11.56,
11.61, 14.24, 16.49, 16.78, 16.92, 22.32, 26.35, 26.44, 34.74, 35.06,
35.20, 35.24, 35.88, 60.89, 73.46, 74.14, 74.61, 74.76, 108.39, 109.68,
110.88, 116.41, 120.89, 121.71, 122.67, 123.11, 125.27, 126.49, 127.40,
127.61, 127.68, 127.80, 127.86, 133.79, 137.83, 150.53, 150.96, 151.30,
151.78, 155.65, 171.22. UV-vis (CH2Cl2): 407 (51000), 329 (26000).
MALDI-TOF-MS (MW ) 799.10) m/z ) 799.29. Anal.Calcd. for
C48H68N2O7: C 73.44, H 8.73, N 3.57. Found: C 73.16, H 8.87, N
3.33.
1
1464, 1416, 1389, 1346, 1251, 1200, 1043, 967, 852 cm-1. H NMR
(CDCl3): δ 0.9-1.11 (m, 36H), 1.25 (t, 3H), 1.33-2.0 (m, 26H), 2.24
(s, 3H), 2.53 (t, 2H) 3.15 (dt, br., 2H), 3.47 (m, br., 4H), 3.74-4.04
(m, 12H), 4.14 (q, 2H), 4.60 (s, br., 1H), 5.02 (t, br., 1H), 6.73 (s, 1H),
7.10 (s, 1H), 7.17 (s, 1H), 7.19 (s, 1H), 7.21 (s, 1H), 7.44 (d, 1H),
7.48 (d, 1H), 7.52 (d, 1H), 7.58 (d, 1H), 7.76 (s, 1H), 8.17 (t, br., 1H).
13C NMR (CDCl3): δ 11.29, 11.36, 11.45, 14.17, 16.40, 16.69, 16.73,
16.82, 26.15, 26.24, 26.32, 26.35, 29.57, 29.79, 34.88, 34.92, 34.95,
35.03, 35.09, 35.85, 39.39, 40.2, 60.57, 73.37, 74.01, 74.09, 74.21,
74.28, 74.64, 108.37, 109.56, 109.81, 110.25, 115.58, 116.27, 120.59,
121.57, 121.80, 123.39, 125.03, 125.07, 126.39, 127.71, 128.28, 131.22,
150.47, 150.76, 150.93, 151.25, 151.67, 158.08, 165.27, 173.02. UV-
vis (CH2Cl2): 420 (44 000), 320 (20000). MALDI-TOF-MS (MW )
1098.55) m/z ) 1098.66. Anal.Calcd. for C66H103N3O10: C 72.16, H
9.45, N 3.82. Found: C 72.06, H 9.38, N 3.71.
(E,E)-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-bis-
[(S)-methyl butoxy]styryl}nitrobenzene (7). To a solution of diethyl-
(4-nitrobenzyl) phosphonate (1.20 g, 4.40 mmol) in anhydrous DMF
(20 mL) under argon was added KtBuO (0.59 g, 5.20 mmol) at room
temperature. After stirring for 15 min, a solution of aldehyde 618 (2.27
g, 4.00 mmol) in 30 mL DMF was added dropwise. The solution was
stirred for 4 h and subsequently poured onto a mixture of 100 g crushed
ice and 45 mL HCl (6 N) was added. The mixture was extracted three
times with CH2Cl2 and the collected organic fractions were washed
with 3N HCl and dried over MgSO4. After evaporation of the solvent
the compound was recrystallized twice from hexane to afford 2.24 g
(82%) of 7 as small deep red crystals. Mp: 137 °C. IR (UATR) v
3053, 2958, 2920, 2874, 1626, 1587, 1506, 1464, 1424, 1333, 1256,
1243, 1203, 1108, 1043, 964, 857, 749, 691 cm-1. 1H NMR (CDCl3):
δ 0.89-1.19 (m, 24H), 1.20-1.48 (m, 4H), 1.50-1.78 (m, 4H), 1.82-
2.06 (m, 4H), 2.25 (s, 3H), 3.70-3.97 (m, 8H), 6.76 (s, 1H), 7.12 (s,
1H), 7.13 (s, 1H), 7.21 (d, 1H), 7.23 (s,1H), 7.49 (d, 1H), 7.58 (d,1H),
7.62 (d,2H), 7.66 (d, 1H), 8.22 (d, 2H). 13C NMR (CDCl3): δ 11.37,
11.47, 11.51, 16.43, 16.68, 16.79, 16.85, 26.22, 26.33, 34.91, 35.07,
35.10, 73.30, 73.85, 74.43, 74.51, 108.20, 109.32, 111.12, 116.17,
121.21, 123.92, 124.12, 124.77, 125.83, 126.56, 127.94, 128.28, 129.35,
144.73, 146.36, 150.72, 151.62, 151.77. UV-vis (CH2Cl2): 442
(39000), 332 (23000). MALDI-TOF-MS (MW ) 685.43) m/z )
685.59 [M+]. Anal.Calcd. for C43H59NO6: C 75.29, H 8.67, N 2.04.
Found: C 74.91, H 8.80, N 1.99.
(E,E,E)-4-[4-{3,4,5-Tridodecyloxystyryl)-2,5-bis[(S)-2-methylbu-
toxy]styryl}-2,5-bis[(S)-2-methylbutoxy]styryl}phenyl]ureido acetic
acid methyl ester (12). To a stirred solution of (E,E,E)-4-[4-{3,4,5-
Tridodecyloxystyryl)-2,5-bis[(S)-2-methylbutoxy]styryl}-2,5 -bis[(S)-
2-methylbutoxy]styryl] phenyl isocyanate (11)19 in dry CH2Cl2 (3 mL)
was added Et3N (0.4 mL) and glycine methyl ester hydrochloride (53
mg, 1.1 equiv). The mixture was stirred overnight at room temperature.
The product was washed with diluted aqueous hydrochloride solution
(0.2 M) and a saturated solution of NaCl. The organic layer was dried
over Na2SO4, filtrated and concentrated in vacuo to yield 0.4 g of 12
(80% yield) as a yellow solid. Mp: 134 °C. IR (UATR) v 3340, 3054,
2957, 2920, 2852, 1746, 1705, 1673, 1621, 1579, 1505, 1466, 1422,
(E,E)-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-bis-
[(S)-2-methyl butoxy]styryl}aniline (8). Under an argon atmosphere,
7 (988 mg 1.44 mmol) was suspended in a mixture of 10 mL ethanol
and 8 mL ethyl acetate and 2.6 g (11.52 mmol) of SnCl2 ‚ 2H2O was
added. The reaction mixture was heated to 75°C, stirred for 5 h, cooled
to room temperature and subsequently poured into crushed ice. The
aqueous phase was extracted with diethyl ether and the organic layer
dried over MgSO4, filtrated, and the solvent remove in vacuo.
Purification by column flash chromatography using hexane/ethyl acetate
3:1 (v/v) as eluent yielded 660 mg (70%) of 8 as an orange solid. Mp:
106 °C. IR (UATR) v 3388, 3045, 2959, 2916, 2873, 1618, 1506, 1461,
1412, 1388, 1342, 1253, 1197, 1040, 964, 852, 815, 713 cm-1. 1H NMR
(CDCl3): δ 0.89-1.19 (m, 24H), 1.20-1.48 (m, 4H), 1.50-1.78 (m,
4H), 1.82-2.06 (m, 4H), 2.25 (s, 3H), 3.70-3.97 (m, 8H), 6.70 (d,
2H), 6.84 (s, 1H), 7.19 (d, 1H), 7.22 (s, 1H), 7.25 (s, 1H), 7.32 (s,
1H), 7.43 (d, 1H), 7.44 (d, 2H), 7.60 (d, 1H), 7.66 (d, 1H). 13C NMR
(CDCl3): δ 11.54, 11.57, 11.67, 11.72, 16.55, 16.88, 16.97, 17.00,
17.03, 26.46, 26.54, 26.58, 34.17, 35.20, 35.39, 73.47, 74.21, 74.62,
74.77, 108.33, 109.70, 110.75, 115.31, 116.50, 119.88, 121.86, 122.77,
125.47, 127.14, 127.40, 127.56, 128.65, 128.93, 146.45, 150.63, 151.14,
151.21, 151.90. UV-vis (CH2Cl2): 408 (39000), 329 (20000). MALDI-
TOF-MS (MW ) 655.46) m/z ) 655.60 [M+].
1
1387, 1340, 1245, 1203, 1119, 1046, 963, 851, 721 cm-1. H NMR
(CDCl3): δ 0.80-1.18 (m, 33H), 1.18-1.92 (m, 68H), 1.92-2.05 (m,
4H), 3.7 (s, 3H), 3.75 (d, 2H), 3.78-4.08 (m, 14H), 5.85 (t, 1H), 6.64
(d, 2H), 6.75 (s, 2H), 7.04 (d, 1H), 7.07 (d, 1H), 7.10 (s, 1H), 7.11 (s,
1H), 7.19 (s, 1H), 7.21 (s, 1H), 7.31(d, 1H), 7.34 (d, 2H), 7.41(d, 1H),
7.49 (s, 2H), 7.53 (s, br., 1H). 13C NMR (CDCl3): δ 11.53, 11.63,
11.67, 14.25, 16.92, 17.00, 22.84, 26.29, 26.51, 29.52, 29.55, 29.59,
29.82, 29.86, 29.89, 29.91, 30.51, 32.08, 35.14, 35.24, 35.31, 41.20,
53.11, 69.20, 73.66, 74.21, 74.29, 74.58, 105.18, 109.74, 109.93, 110.62,
115.31, 119.94, 122.27, 122.70, 122.86, 126.76, 126.88, 127.63, 127.75,
9
J. AM. CHEM. SOC. VOL. 125, NO. 42, 2003 12959

A R T I C L E S
Precup-Blaga et al.
127.83, 128.59, 128.78, 128.93, 133.43, 138.25, 146.23, 151.14, 151.19,
151.33, 153.39, 158.70, 176.50. UV-vis (CH2Cl2): 433 (56000), 333
(28000). MALDI-TOF-MS (MW ) 1412.098) m/z ) 1412.105 [M]+.
Anal.Calcd. for C90H142N2O10: C 76.55, H 10.14, N 1.98. Found: C
76.74, H 10.39, N 2.22.
962, 849, 668 cm-1. 1H NMR (DMSO): δ 0.88-1.04 (m, 24H), 1.22-
1.33 (m, 4H), 1.48-1.60 (m, 4H), 1.78-2.15 (m, 4H), 2.14 (s, 3H),
3.70-3.91 (m, 8H), 3.78 (d, 2H), 6.42 (s, br., 1H), 6.83 (s, 1H), 7.02
(s, 1H), 7.11 (s, 1H), 7.24 (d, 2H), 7.25 (s, 1H), 7.36 (d, 2H), 7.4-
7.45 (m, 4H), 7.61 (s, br., 1H). --
General Procedure for the Hydrolysis of the Ester Derivatives
to Obtain the OPV Guests. To a solution of ester (1 equiv) in THF
was added 7 equiv of LiOH‚H2O. The solution was stirred overnight
(15 h) and the acid was precipitated by acidification with HCl 1M (pH
) 2). The resulting solid was filtered off, dried under high vacuum
and then washed with hexane at room temperature. Conjugated guests
OPV1, OPV2, OPV3, OPV4, and OPV5 were obtained with quantita-
tive yield as a yellow solid.
(E,E)-3-{3-[4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-methyl butoxy]styryl}phenyl]ureido} propionic acid (OPV4).
Mp: 150 °C. IR (UATR) v 3322, 3056, 2960, 2920, 2875, 1706, 1644,
1590, 1540, 1510, 1463, 1412, 1386, 1342, 1311, 1239, 1197, 1043,
964, 851, 668 cm-1. 1H NMR (CDCl3): δ 0.94-1.11 (m, 24H), 1.26-
1.37 (m, 4H), 1.56-1.67 (m, 4H), 1.87-1.97 (m, 4H), 2.23 (s, 3H),
2.54 (t, br., 2H), 3.47 (dt, br., 2H), 3.73-3.94 (m, 8H), 5.87 (s, br.,
1H), 6.71 (s, 1H), 7.07 (s, 1H), 7.08(d, 1H), 7.09(s, 1H), 7.16 (s, 1H),
7.32 (d, 2H), 7.38 (d, 1H), 7.43 (d, 1H), 7.44 (d, 2H) 7.49 (d, 1H),
7.62 (s, br., 1H). 13C NMR (CDCl3): δ 11.36, 11.46, 11.51, 16.38, 16.67,
16.78, 16.86, 26.23, 26.32, 34.92, 34.95, 35.09, 35.13, 35.72, 73.34,
74.03, 74.48, 74.65, 108.24, 109.52, 110.80, 116.29, 120.56, 121.56,
122.55, 122.98, 125.14, 126.34, 127.26, 127.57, 127.69, 127.76, 133.59,
137.64, 150.41, 150.85, 151.18, 151.67, 156.62, 176.99. UV-vis (CH2-
Cl2): 408 (44000), 329 (18000). MALDI-TOF-MS (MW ) 771.05)
m/z ) 771.23. Anal. Calcd. for C47H66N2O7 (MW ) 771.05): C 73.21,
H 8.63, N 3.63. Found: C 73.23, H 8.64, N 3.65.
(E,E,E)-4-[4-{3,4,5-Tridodecyloxystyryl)-2,5-bis[(S)-2-methylbu-
toxy]styryl}-2,5-bis[(S)-2-methylbutoxy]styryl] ureido acetic acid
(OPV5). Mp: 122 °C. IR (UATR) v 3341, 3053, 2957, 2921, 2853,
1649, 1590, 1545, 1504, 1466, 1421, 1386, 1340, 1238, 1202, 1117,
1045, 962, 851, 668 cm-1. 1H NMR (CDCl3): δ 0.80-1.18 (m, 33H),
1.18-1.92 (m, 68H), 1.92-2.05 (m, 4H), 3.75 (d, 2H), 3.78-4.08 (m,
14H), 5.85 (t, 1H), 6.64 (d, 2H), 6.75 (s, 2H), 7.04 (d, 1H), 7.07 (d,
1H), 7.10 (s, 1H), 7.11 (s, 1H), 7.19 (s, 1H), 7.21 (s, 1H), 7.31(d, 1H),
7.34 (d, 2H), 7.41 (d, 1H), 7.49 (s, 2H), 7.53 (s, br., 1H). 13C NMR
(CDCl3): δ 11.53, 11.63, 11.67, 14.25, 16.92, 17.00, 22.84, 26.29,
26.51, 29.52, 29.55, 29.59, 29.82, 29.86, 29.89, 29.91, 30.51, 32.08,
35.14, 35.24, 35.31, 41.20, 69.20, 73.66, 74.21, 74.29, 74.58, 105.18,
109.74, 109.93, 110.62, 115.31, 119.94, 122.27, 122.70, 122.86, 126.76,
126.88, 127.63, 127.75, 127.83, 128.59, 128.78, 128.93, 133.43, 138.25,
146.23, 151.14, 151.19, 151.33, 153.39, 158.70, 176.50. UV-vis (CH2-
Cl2): 434 (54000), 336 (10000). MALDI-TOF-MS (MW ) 1398.071)
m/z ) 1397.98 [M]+. Anal. Calcd. for C89H140N2O10 (MW ) 1398.071):
C 76.46, H 10.09, N 2.00. Found: C 76.45, H 10.10, N 1.98.
(E,E)-6-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-2-methyl butoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]benzoy-
lamino}-hexyl ureido-acetic acid (OPV1). Mp; 166 °C. IR (UATR)
v 3353, 3056, 2959, 2925, 2858, 1712, 1635, 1593, 1547, 1506, 1464,
1
1415, 1388, 1342, 1250, 1197, 1045, 965, 851, 668 cm-1. H NMR
(CDCl3): δ 0.9-1.11 (m, 36H), 1.25-2.0 (m, 26H), 2.24 (s, 3H), 3.2
(dt, br., 2H), 3.47 (dt, br., 2H), 3.74-4.04 (m, 14H), 5.70 (s, br., 1H),
5.85 (s, br., 1H), 6.73 (s, 1H), 7.10 (s, 1H), 7.16 (s, 1H), 7.18 (s, 1H),
7.21 (s, 1H), 7.44 (d, 1H), 7.47 (d, 1H), 7.51 (d, 1H), 7.58 (d, 1H),
7.69 (s, 1H), 8.34 (t, br., 1H). 13C NMR (CDCl3): δ 11.28, 11.36,
11.46, 16.40, 16.69, 16.73, 16.80, 25.34, 25.73, 26.25, 26.33, 26.35,
29.16, 29.41, 29.68, 34.89, 34.94, 34.96, 35.02, 35.03, 35.10, 39.27,
39.83, 43.27, 73.38, 74.02, 74.09, 74.24, 74.28, 74.65, 108.38, 109.53,
109.81, 110.25, 115.43, 116.27, 119.82, 121.56, 121.64, 123.45, 125.06,
125.32, 126.38, 127.74, 128.4, 131.74, 150.48, 150.77, 150.93, 151.28,
151.40, 151.68, 159.62, 165.92, 173.35. MALDI-TOF-MS (MW )
1056.47) m/z ) 1056.26. UV-vis (CH2Cl2): 421 (36000), 322 (11900).
Anal. Calcd. for C63H97N3O10 (MW ) 1056.47): C 71.62, H 9.25, N
3.98. Found: C 71.61, H 9.23, N 3.97.
(E,E)-3-[-6-{-4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-
2,5-bis[(S)-2-methylbutoxy]styryl}-2,5-bis[(S)-2-methylbutoxy]-
benzoylamino}hexylureido] propionic acid (OPV2). Mp: 172 °C.
IR (UATR) v 3380, 3053, 2959, 2927, 2874, 1727, 1620, 1600, 1543,
1505, 1463, 1415, 1386, 1343, 1250, 1199, 1044, 965, 851, 668 cm-1
.
1H NMR (CDCl3): δ 0.9-1.11 (m, 36H), 1.33-2.0 (m, 26H), 2.24 (s,
3H), 2.58 (t, 2H) 3.17 (dt, br., 2H), 3.48 (m, br., 4H), 3.74-4.04 (m,
12H), 5.37 (s, br., 1H), 5.45 (s, br., 1H), 6.73 (s, 1H), 7.10 (s, 1H),
7.17 (s, 1H), 7.19 (s, 1H), 7.21 (s, 1H), 7.44 (d, 1H), 7.48 (d, 1H),
7.52 (d, 1H), 7.58 (d, 1H)0.7.72 (s, 1H), 8.34 (t, br., 1H). 13C NMR
(CDCl3): δ 11.28, 11.37, 11.47, 16.41, 16.70, 16.76, 16.79, 16.80, 16.83,
25.69, 26.18, 26.26, 26.33, 26.36, 29.21, 29.75, 34.91, 34.95, 34.96,
35.02, 35.05, 35.10, 35.57, 39.23, 39.52, 40.15, 73.38, 74.09, 74.10,
74.24, 74.29, 74.65, 108.38, 109.51, 109.82, 110.26, 115.59, 116.28,
119.94, 121.56, 121.67, 123.45, 125.06, 125.28, 126.30, 127.74, 128.39,
131.66, 150.48, 150.75, 150.93, 151.28, 151.42, 151.68, 159.13, 165.78.
UV-vis (CH2Cl2): 423 (45000), 325 (15000). MALDI-TOF-MS (MW
) 1070.50) m/z) 1070.61. Anal. Calcd. for C64H99N3O10 (MW)
1070.50): C 71.81, H 9.32, N 3.93. Found: C 71.83, H 9.33, N 3.93.
(E,E)-3-[4-{4-(4-Methyl-2,5-bis[(S)-2-methylbutoxy]styryl)-2,5-
bis[(S)-methyl butoxy]styryl}phenyl]ureido acetic acid (OPV3).
Mp: 159 °C. IR (UATR) v 3338, 2959, 2918, 2875, 1739, 1698, 1641,
1590, 1555, 1510, 1463, 1412, 1389, 1342, 1309, 1236, 1203, 1045,
Acknowledgment. We would like to thank Dr. Annika J.
Karlsson for stimulating discussions and assistance with the 2D
NMR 1H, 1H NOESY measurements. We like to acknowledge
Joost van Dongen for performing MALDI TOF measurements,
Dr. John van Haaren, and Dr. Simone Vulto for their help with
external quantum efficiencies measurements, Bas de Waal for
his help with the synthesis and Pascal Jonkheijm for his help
with the AFM measurements. The research of A.P.H.J. Schen-
ning has been made possible by a fellowship of the Royal
Netherlands Academy of Arts and Sciences. This work has been
supported by The Netherlands Organization of Scientific
Research (NWO, PPM).
JA0211050
9
12960 J. AM. CHEM. SOC. VOL. 125, NO. 42, 2003