Towards highly fluorescent and water-soluble perylene dyes

Article abstract of DOI:10.1002/chem.200400291

A systematic approach towards highly fluorescent, water-soluble perylene-3,4:9,10-tetracarboxylic acid diimide chromophores is presented. Water solubility was introduced first through the attachment of four hydrophilic substituents onto the bay region of

Full text of DOI:10.1002/chem.200400291

FULL PAPER
Towards Highly Fluorescent and Water-Soluble Perylene Dyes
Christopher Kohl, Tanja Weil, Jianqiang Qu, and Klaus Müllen*[a]
Abstract: A systematic approach to-
wards highly fluorescent, water-soluble
perylene-3,4:9,10-tetracarboxylic acid
diimide chromophores is presented.
Water solubility was introduced first
through the attachment of four hydro-
philic substituents onto the bay region
of the perylene dye. Positively and neg-
atively charged groups were then ap-
plied to the chromophore, and their
number and their distance from the ar-
omatic scaffold were systematically
varied. To suppress aggregation, the
chromophore was further isolated
within a dendritic shell. Such variation
of structural features and a thorough
investigation of the resulting optical
properties facilitated the first synthesis
of
perylene-3,4:9,10-tetracarboxylic
acid diimides combining the properties
of water solubility and fluorescence
quantum yields (FQYs) close to unity,
which makes them attractive as high-
performance fluorescence probes in
aqueous media.
Keywords: aggregation
· fluores-
cence · perylene · polyphenylene
dendrimer · water solubility
Introduction
fluorescence quantum yields close to unity.[8–11] Thanks to
these remarkable properties they are used as dye sensitizers
in solar cells,[12,13] molecular components of light-emitting
diodes,[14] or field effect transistors.[15,16] Recently, their ap-
plicability in single-molecule spectroscopy has been success-
fully demonstrated in investigations of the optical behavior
of multichromophoric dendrimers.[17,18] Therefore, thanks to
these unique properties, PDI chromophores should also be
ideally suited as high-performance fluorescent labels for bio-
logically active probes. Only a few water-soluble perylene
monoimide and PDI derivatives have so far been reported,
however. Such chromophores carry hydrophilizing substitu-
ents, such as sulfonic acid moieties (1),[19] quaternized amine
groups (2),[20] (Figure 1) or crown ethers[21] as part of the
imide structure of the chromophore, or polyethylene
glycol[22,23] or peptide chains[24] attached to the chromophore
scaffold. In all cases these perylene chromophores show
almost no fluorescence in water. Until now there has been
no synthetic strategy for obtaining PDI chromophores that
will retain their exceptional properties in aqueous media.
Herein we introduce different structural concepts for
highly fluorescent and water-soluble PDI chromophores.[25]
In the course of this work, several hydrophilic groups were
attached to the aromatic chromophore scaffold. Further-
more, the distance between such water solubility-inducing
groups and the chromophore was increased to suppress fluo-
rescence quenching due to photoinduced electron transfer[26]
between the functional group and the chromophore. The
chromophore was then encapsulated within a dendritic shell,
which is likely to prevent intermolecular chromophore inter-
action such as aggregation.[27,28] The number of hydrophilic
or charged groups was then reduced. Through this systemat-
Fluorescence is ideally suited for observation of the location
and interaction of biologically active probes in vivo, since it
is non-invasive and can be detected with high sensitivity and
signal specificity.[1] In particular, in vivo investigations of bi-
ological targets require chromophores giving high fluores-
cence quantum yields (FQYs) in water and displaying ab-
sorption and emission maxima in an area that does not in-
terfere with the self-absorption wavelength of the cell:
above 500 nm, for example.[2,3] In recent years the investiga-
tion of individual biologically active macromolecules such as
DNA and proteins has become very popular since it pro-
vides better insight into their dynamics and interaction part-
ners than measurements made on ensembles.[4–7] For such
measurements, however, the photostability of the chromo-
phore plays a crucial role. Despite the large variety of
water-soluble chromophores commercially available today,[8]
there are almost no chromophores that meet all the follow-
ing criteria: i) water solubility, ii) high fluorescence intensi-
ties, iii) absorption and emission maxima above 500 nm,
iv) no toxicity, and v) high photostability.
In organic solvents, perylene-3,4:9,10-tetracarboxylic acid
diimide (PDI) chromophores (Figure 1a) display exception-
al chemical, thermal, and photochemical stability with high
[a] Dr. C. Kohl, Dr. T. Weil, Dr. J. Qu, Prof. K. Müllen
Max-Planck-Institut für Polymerforschung
Ackermannweg 10, 55128 Mainz (Germany)
Fax : (+49)6131-379350
E-mail: muellen@mpip-mainz.mpg.de
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DOI: 10.1002/chem.200400291
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FULL PAPER
Results and Discussion
Variation of the hydrophilic
group attached at the bay
region: PDI chromophores bear-
ing hydrophilic substituents at-
tached to the imide structure of
the chromophore generally dis-
play low FQYs in water.[19–21]
We therefore first introduced
such groups onto the bay region
of the chromophore (Figure 1a),
which results in a nonplanar,
twisted aromatic chromophore
scaffold (Figure 1b) that is fur-
ther shielded by the functional
groups.[28]
Based on this concept, the
synthesis of 5 with four carbox-
ylic acid substituents attached at
the bay region was accomplish-
ed through treatment of N,N’-
bis(2,6-diisopropylphenyl)-
Figure 1. a) PDI bearing substituents attached at the imide structure; b) three-dimensional structure of PDI
with no substituents attached at the bay region (planar scaffold)—view in the direction of the bay region;
c) three-dimensional structure with four substituents attached at the bay region (twisted scaffold).
1,6,7,12-tetrachloroperylene-
ic variation of all available parameters and thorough investi-
gation of the optical properties of all water-soluble chromo-
phores we were able to develop highly fluorescent, water-
soluble PDI chromophores.
3,4:9,10-tetracarboxylic acid diimide (3), which is available
on a gram scale,[29] with six equivalents of methyl (4-hyroxy-
phenyl)acetate (4) in 1-methyl-2-pyrrolidone (NMP) (85%
yield, Scheme 1). Since this chromophore is not soluble in
water, its sodium salt was prepared by addition of sodium
hydroxide dissolved in methanol to a concentrated THF so-
Scheme 1. i) Methyl (4-hydroxyphenyl)acetate (4), NMP, K2CO3, 1008C, 15 h, 85%; ii) THF, methanol/sodium hydroxide; iii) phenol, NMP, K2CO3, 808C,
15 h, 89%; iv) conc. sulfuric acid, RT 15 h, 93%.
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Fluorescent Water-Soluble Perylene Dyes
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lution of 5. The synthesis of a PDI chromophore with four
sulfonic acid substituents (9) was performed by a two-step
reaction (Scheme 1). The first step involved a phenoxylation
of 3 by treatment with phenol (7), affording 8 in high yield.
Compound 8 was then treated with concentrated sulfuric
acid at room temperature for 15 h. The number of sulfonic
acid groups and the substitution pattern of the phenyl ring
(para substitution) were corroborated by NMR experiments
(see Experimental Section).
PDI chromophores bearing positively charged branches
attached at their bay regions were obtained by treatment of
3 with six equivalents of 4-[2-(dimethylamino)ethyl]phenol
(10) in NMP as shown in Scheme 2. Interestingly, the analo-
gous reaction between 3 and six equivalents of 4-dimethyl-
aminophenol (13), which would have given 14 with four di-
methylaminophenoxy branches, was not observed. There-
after, quaternization of the dimethylamino substituents of
11 was carried out by treatment first with an excess of
methyl iodide in boiling chloroform for 24 h and then with
an additional excess of methyl iodide in boiling methanol
for another 24 h. Since the resulting chromophore 12a was
insoluble in water, four equivalents of silver methanesulfo-
nate were applied, the counterion being exchanged from
iodide to methanesulfonate to give water-soluble 12b as a
dark red solid.
The synthesis of the pyridinium-substituted PDI chromo-
phores 17a and 17b (Scheme 2) involved phenoxylation
with 3-pyridinol (15) by the same procedure as described
above, to yield 16 (85%). Because of the high solubility of
16 in alcohol, quaternization of 16 was carried out with an
excess of methyl iodide in methanol to give 17a. To increase
the solubility in water, four equivalents of silver methanesul-
fonate were applied, and 17b was obtained in quantitative
yield.
Variation of the distance between the hydrophilic group and
the chromophore: To observe the influence on the FQY of
the distance separating the hydrophilic groups and the chro-
mophore scaffold, chromophores bearing one additional
phenyl ring per side arm as a spacer were synthesized
Scheme 2. i) 4-[2-(Dimethylamino)ethyl]phenol (10), NMP, K2CO3, 808C, 15 h, 79%; ii) 12a: methyl iodide, methanol, reflux, 24 h, 95%; 12b: silver
methanesulfonate, methanol, RT, 5 h, 95%; iii) 3-pyridinol (15), NMP, K2CO3, 808C, 15 h, 85%; iv) 17a: methyl iodide, methanol, reflux, 24 h, 95%;
17b: silver methanesulfonate, methanol, RT, 5 h, 92%.
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K. Müllen et al.
FULL PAPER
(Scheme 3). First, N,N’-bis(2,6-diisopropylphenyl)-1,6,7,12-
tetrachloroperylene-3,4:9,10-tetracarboxylic acid diimide (3)
was treated with six equivalents of 4-bromophenol to give
18 in high yield (92%). Compound 18 was then subjected to
Suzuki reaction conditions[30,31] with either 4-dimethylamino-
phenylboronic acid (19) or pyridine-3-boronic ester (20) to
give 21 and 22, respectively, with side arms each containing
an additional phenyl ring with respect to the analogous
chromophores 12 and 17. Water-soluble chromophores 23b
and 24b were obtained in nearly quantitative yield by initial
application of methyl iodide in boiling chloroform and sub-
sequent exchange of the counterion for methanesulfonate
by treatment with four equivalents of silver methanesulfonate.
ment of 25 with tetraphenylcyclopentadienone 29a
(Scheme 5), bearing two imino groups,[22,35] gave dendrimer
30a with eight imino groups. After hydrolysis of these imino
groups by treatment with hydrochloric acid, compound 31a,
bearing eight amino groups, was isolated (94% yield). The
synthesis of 30b, with eight methyl carboxylate substituents,
was achieved by treatment of 25 with tetraphenylcyclopenta-
dienone 29b at 1758C for 40 h. Subsequent ester cleavage of
30b with potassium hydroxide in THF at 808C gave 31b,
with eight carboxylic acid functions. Compound 30c, bearing
12 tetraethylene glycol chains, was obtained through cyclo-
addition between 25 and 29c (56% yield). The synthesis
and characterization of the cyclopentadienone building units
26, 29b, and 29c has been described before.[22,35]
Site isolation of the chromophore: To prevent PDI chromo-
phores from aggregating, bulky substituents such as poly-
phenylene dendrimer branches attached at the bay region of
the chromophore were produced by means of successive
Diels–Alder reactions.[32,33] Scheme 4 shows the synthesis of
a dendronized PDI bearing positively charged groups at the
surface, together with the three-dimensional structure of a
PDI chromophore surrounded by four bulky polyphenylene
branches. The starting point was a PDI core 25 with four
free ethynyl functionalities, which were subjected to four
Diels–Alder cycloadditions by treatment with a sixfold
excess of the tetraphenylcyclopentadienone derivative 26,
bearing two dimethylamino substituents, in m-xylene at
1408C.[34] The resulting first-generation dendrimer 27, with
eight dimethylamino groups, was obtained in high yield.
Quaternization of 27 was then accomplished with an excess
of dimethylsulfate by constant addition of chloroform to a
benzene solution. Finally, the complete quaternization suc-
ceeded in methanol, to provide 28 in 62% yield.
Variation of the number of hydrophilic groups: To reduce
unwanted quenching processes due to the presence of the
solubilizing groups themselves, PDI derivatives with only
two charged branches were synthesized. Since the water sol-
ubility of the chromophores decreases with a decreasing
number of hydrophilic substituents, only groups likely to
induce high solubility in water—such as pyridinium and sul-
fonic acid—were chosen. First, 1,7-dibromoperylenetetracar-
boxylic acid diimide 32 (Scheme 6) was treated with 2,6-di-
isopropylaniline in propionic acid to give 33 in high yield
(95%). PDI chromophores either with two pyridinium sub-
stituents (34a) or with two phenoxy groups (34b) were then
obtained by the same procedure as described for the synthe-
sis of 9 and 16. First, 33 was treated with 3-pyridinol (15) in
NMP to afford 34a in 75% yield. Quaternization of 34a was
carried out by treatment with an excess of methyl iodide in
boiling chloroform, which gave 35a in quantitative yield.
Compound 35b was obtained by application of silver metha-
nesulfonate in methanol. Compound 34b was produced by
phenoxylation of 33 by treatment with phenol in NMP. Sub-
sequently, the sulfonation was carried out by treatment with
Polyphenylene dendrimers with PDI cores bearing amino,
carboxylic acid, and tetraethylene glycol functions were ob-
tained by the same synthetic sequence. In this way, treat-
Scheme 3. i) 4-Bromophenol, NMP, K2CO3, 808C, 15 h, 91%; ii) a: 19, [Pd(Ph3)4], toluene, K2CO3/H2O (1m), 958C, 12 h, 90%; b: 20, [Pd(Ph3)4], toluene,
K2CO3/H2O (1m), 958C, 12 h, 84%; iii) a: methyl iodide, methanol, reflux, 24 h, 94%; b: silver methanesulfonate, methanol, RT, 5 h, 90%.
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Fluorescent Water-Soluble Perylene Dyes
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Scheme 4. i) Compound 26, m-xylene, 12 h, reflux, 92%; ii) a: methyl iodide, benzene, reflux, 4 h, b: silver methanesulfonate, methanol, RT, 5 h, 92%.
concentrated sulfuric acid at room temperature for 15 h to
give 35c as a red solid in 94% yield.
ready offers a good impression of the lightfastness of these
novel chromophores.
One of the key features of the ionic PDI chromophores is
their outstanding water solubility. Compound 17b has the
highest solubility in water (8.0”10À2 molLÀ1). The solubility
of the other chromophores can be estimated from their cal-
culated log D values[36] (logarithm of the octanol/water par-
tition coefficient as a function of pH) given in Figure 2. In
general, water-soluble compounds are characterized by low
log D values, whereas high log D values describe lipophilic
compounds. Figure 2 shows that chromophores 1, 2, 6
(above pH 9), and 9 should be nicely soluble in water,
whereas lower water solubility is to be expected in the cases
of chromophores 17, 12, 35a, and 35c. Furthermore, with a
decreasing number of hydrophilic groups—from four (9, 17)
down to two (35a, 35c)—an increase in the log D value is
obtained and so lower water solubility is to be expected.
The introduction of a phenyl spacer (chromophores 23 and
24) gives highly lipophilic compounds in which only very
limited water solubility is to be anticipated. However, since
neither the distribution of hydrophilic groups in the mole-
cule nor the nature of the charged counter-ion is recognized
by log D values, the water solubilities of chromophores 12,
17, 23, 24, and 35a are likely to be underestimated.
Characterization: All chromophores described here display
good thermal stability, with decomposition temperatures
above 3008C. Each structure has been verified by NMR
spectroscopy, field desorption (FD) mass spectrometry, and/
or matrix-assisted laser desorption/ionization time of flight
(MALDI-TOF) spectrometry. In the cases of positively
charged chromophores not detected by the mass spectrome-
try techniques applied here, only 1H NMR and 13C NMR
spectroscopy and elementary analysis were applied. The
MALDI-TOF mass spectra of all uncharged and negatively
charged chromophores reported here each show only a
single peak corresponding to the molecular mass of the
chromophore. The perfect agreement between the calculat-
ed and experimentally determined m/z ratios confirms the
monodispersity of this dendrimer.
Photostability/solubility: The ionic PDI chromophores re-
ported for the first time here display high photostability in
aqueous media, comparable to that of PDIs in organic sol-
vents or in the solid state. The UV/Vis absorption and emis-
sion spectra of water solutions of these dyes remain almost
unchanged under sunlight or after irradiation under UV
light (365 nm) for one week. This basic photostability test al-
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K. Müllen et al.
FULL PAPER
Scheme 5. i) Compound 29a, o-xylene, 20 h, 1708C, 89%; ii) compound 30a, THF, HCl (5m), 94%; iii) compound 29b, o-xylene, diphenyl ether, 40 h,
1758C, 60%; iv) compound 30b, THF, KOH, H2O, 42 h, 808C, 98%; v) compound 29c, o-xylene, 24 h, 1708C, 47%.
Scheme 6. i) 2,6-Diisopropylaniline, propionic acid, 1408C, 5 h, 95%; ii) a: compound 33, 3-pyridinol (15), NMP, K2CO3, 808C, 15 h, 81%; b: compound
33, phenol, NMP, K2CO3, 808C, 15 h, 80%; iii) a: compound 34a, methyl iodide, chloroform, reflux, 24 h, b: compound 34a, methyl iodide, methanol,
reflux, 24 h, 94%; silver methanesulfonate, methanol, RT, 5 h, 90%; c: compound 34b, conc. sulfuric acid, RT, 15 h, 94%.
Optical characterization: The absorption and emission
maxima of compounds 6, 9, 12b, and 17b are listed in
Table 1. A PDI chromophore bearing phenoxy substituents
in the bay region displays three absorption maxima at 577,
537, and 444 nm[28] and one emission maximum at 600 nm in
toluene. The spectra of chromophores 6, 9, 12b, and 17b
with hydrophilic substituents reveal bathochromic shifts in
water relative to toluene, these being very pronounced in
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Fluorescent Water-Soluble Perylene Dyes
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The FQYs of 9 and 17b (58%, 66%, Table 1) in water
are comparatively high with respect to previously reported
analogous chromophores, indicating the value of our ap-
proach of attaching the functional groups at the bay region
of the chromophore instead of at the imide structure.[19,20]
However, 6 and 12b still display low FQYs (7%, 14%,
Table 1). Clearly, chromophores bearing hydrophilic groups
directly located on the phenyl ring, such as 9 and 17b, and
not at the terminus of a short alkyl chain (6, 12b) show
higher FQYs and less spectral broadening. One reason for
this behavior might be the alkyl spacers in chromophores 6
and 12b, the character of the molecule becoming more lipo-
philic (see Figure 2), which is in accordance with the calcu-
lated log D values of 6 and 12b and leads to a decrease in
solubility and, therefore, a higher tendency of these chromo-
phores to form aggregates. Another reason might be that vi-
brational relaxation becomes more important because of the
higher rotational freedom of the hydrophilic groups of 6 and
12b at the terminus of a short
Figure 2. Log D values as a function of pH for selected PDI chromo-
phores.
Table 1. Absorption (lmax, abs) and fluorescence (lmax, flu) maxima and fluorescence quantum yields (FQYs)[a] in
water for the water-soluble PDI chromophores.
alkyl spacer, leading to
quenching of fluorescence.
a
(a)
Compound
lmax, abs [nm]
lmax, flu [nm]
FQY
(extinction coefficient [mÀ1 cmÀ1])
However, even 9 and 17b,
with FQYs of 58% and 66%,
still display reductions of about
40% in their FQYs with re-
spect to PDI chromophores in
organic solvents, in which the
FQYs are usually close to unity.
In the past, apart from aggrega-
tion[23,28] or vibrational relaxa-
tion, a reduction of the FQY in
polar solvents has also been at-
tributed to the presence of pho-
PDI-(OPh)4
573(43602)[b]
451, 531, 566
600
624
619
627
594
588
614[c]
624
573
594
0.96
0.07
0
6
9
461(10708), 541(21026), 571(27800)
460(13537), 551(25342), 586(35436)
518(19300), 550(25700)
434(9766), 516(24628), 547(33751)
491(17088) 554(24621), 565(27454)
459(19225), 576(25855)
0.58
0.14
12b
17a
17b
23b
24b
35b
35c
0.75
0.66
0.11[c]
0.23
400(4535), 503(13640), 536 nm(19022)
411(7565), 523(23196), 554 nm(23718)
0.98
0.12
[a] Fluorescence quantum yields (FQYs) were measured at room temperature with cresyl violet as reference
(the standard value is 0.54 in methanol). [b] Toluene. [c] Compound 23b has very weak fluorescence in water
and its FQY was measured in DMSO.
toinduced
electron-transfer
(PET) processes.[26] In a case in
the cases of 6 and 12b (36 nm, 39 nm, respectively). The
spectrum of 17b, in contrast to those of 6 and 12b, shows
narrow absorption and emission envelopes that display a
higher degree of fine structure (Figure 3) and a hypsochro-
mic shift of the emission maximum (Table 1).
which triphenylamine groups were attached to a PDI core, it
was demonstrated that PET takes place, resulting in a con-
siderable broadening of the emission spectra and a low
FQY. Since PET strongly depends on the distance separat-
ing the chromophore and the substituent, the role of such
processes in the chromophores reported here should be
quantifiable by increasing the distance between the hydro-
philic group and the chromophore, which should lead to less
PET and therefore higher FQYs.
Nevertheless, the emission spectra of 23b and 24b
(Scheme 3), which each bear one additional phenyl ring per
hydrophilic side arm, again reveal considerable bathochro-
mic shifts, of about 14 nm for 23b in DMSO and 24 nm for
24b in water, relative to 12b and 17b (Figure 4). Further-
more, the FQYs of 23b and 24b are very low in both cases
(11%, 23%). Despite the longer spacer, which increases the
distance between the substituents and the chromophore
scaffold by a factor of about two (Figure 5), the FQYs are
further reduced relative to the analogous chromophores 12b
and 17b without spacers. We again attribute this behavior to
an increase in the lipophilic character of chromophores 23b
and 24b due to the additional phenyl ring, which is also sup-
ported by very high log D values as shown in Figure 2, thus
facilitating aggregation in water.
Figure 3. Normalized absorption spectra and emission spectra of 17b
(c), 12b (g), and 24b (a) in water.
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Table 2. Absorption (lmax, abs) and fluorescence (lmax, flu) maxima and fluo-
rescence quantum yields (FQYs) of the dendronized PDI chromophores
in water(a) or DMSO.
Compound
lmax, abs [nm]
lmax, flu [nm] FQY(a)
(extinction coefficient [mÀ1 cmÀ1])
28
463 (17459), 548 (22965), 589 (36113)
582 (water)
620
615
617
619
606
0.15
0.19
0.012
0.13
0.9
30c
31a
31b
31c
585 (DMSO)
584 (DMSO)
583 (toluene)
[a] FQYs were measured at room temperature with cresyl violet as refer-
ence (the standard value is 0.54 in methanol).
only low FQYs (15%, 13%) in water and DMSO. A FQY
ten times lower is observed for dendrimer 31a, with eight
terminal amino groups, in DMSO; this could be due to the
presence of several terminal amino groups capable of acting
as electron donors, thus quenching the excited state of the
inner PDI chromophore through PET. The low FQY could
not be attributable to the formation of aggregates in any of
the dendritic PDI cases, since their rigid polyphenylene scaf-
folds effectively shield the inner chromophores.[28] There-
fore, with respect to the large size of the dendritic shell,
fluorescence quenching through vibrational relaxation could
play a major role. Nevertheless, in the cases of 18, 30c, and
31b we can only speculate as to whether the reduction in
FQY is based on insufficient water solubility of the den-
drimer, some loss in excitation energy through the dendrim-
er branches, or both. Additional photophysical investiga-
tions will therefore be necessary to understand the low
FQYs of these dendritic chromophores, and these are cur-
rently underway.
Figure 4. Normalized absorption spectra and emission spectra of 23b in
water (a), 23b in DMSO (g), and 24b in methanol (c).
Surprisingly, all the PDI chromophores shielded by poly-
phenylene shells (Scheme 4), which should in general pre-
vent aggregation, also display low FQYs. Table 2 gives an
overview of the optical properties of 18, 30c, 31a, and 31b.
Here, the absorption maxima range between 583 nm and
589 nm, while the emission maxima were found between
615 nm and 620 nm. In toluene, an analogous dendritic chro-
mophore without any substituent 31c[22] reveals similar ab-
sorption maxima, but the emission maximum is shifted by
about 10 nm to the blue.
All polyphenylene dendrimers bearing a PDI chromo-
phore in the center reveal low FQYs in polar solvents such
as dimethyl sulfoxide (DMSO) and water. The highest
FQY—at 19%—was obtained for 30c, with twelve tetra-
ethylene glycol chains at the periphery. Both ammonia- and
carboxylic-acid-terminated dendrimers 28 and 31b display
Since the introduction of a large number of hydrophilic
substituents into the chromophore scaffold resulted only in
weakly fluorescent chromophores, we consequently dimin-
ished their number down to a minimum of two, the mini-
Figure 5. Three-dimensional structure of 17 (left) and 24 (right) with view along the imide structure (middle). Distances from the N heteroatom of the
pyridinium group and the PDI scaffold of 17 (4.5 Š, left) and of 24 (12.8 Š, right).
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mum number necessary to induce sufficient water solubility.
The PDI chromophores 35a and 35b, each bearing only two
substituents in its bay region (Scheme 6), display nearly
quantitative FQYs in aqueous media, and their absorption
and emission spectra are structured, showing a considerable
blue shift with respect to all the chromophores previously
discussed (Figure 6). Apparently, the presence of two posi-
tively charged pyridinium substituents represents a good
compromise for combining sufficient water solubility and a
minimum number of functional groups to suppress unde-
sired processes such as PET.
nied by a considerable decrease in FQY, which was mainly
attributed to the formation of aggregates due to the low sol-
ubility of the resulting chromophores. PDI chromophores
were then encapsulated within rigid dendritic polyphenylene
shells to suppress aggregation completely. Nevertheless,
these chromophores displayed only weak FQYs (1% to
19%), which was mainly attributed to energy loss through
vibrational relaxation together with photoinduced energy
transfer processes between the substituents and the chromo-
phore. The reduction of the number of pyridinium groups
down to a minimum of the two groups indispensable for
providing sufficient water solubility finally resulted in highly
fluorescent chromophores with quantitative FQYs in water.
However, analogous chromophores bearing two sulfonic
acid functions were again only weakly fluorescent. Such dif-
ferences were ascribed mainly to the potential of the hydro-
philic substituent to solubilize the chromophore sufficiently.
Therefore, to obtain water-soluble PDI chromophores with
high FQYs, the nature of the hydrophilic substituent, the
position at which the substituent is attached to the scaffold,
the number of substituents, and the lipophilic character of
the chromophore all have to be adjusted carefully.
The PDI chromophore with two pyridinium arms reported
here represents the first example of a PDI chromophore
combining water solubility with a high FQY in water.
Thanks to high photostability and absorption and emission
maxima above 500 nm, such chromophores are potential
useful, novel, high-performance fluorescence markers in
aqueous media.
Figure 6. Normalized absorption and emission spectra of two-charge-sub-
stituted PDIs 35b (c) and 35c (a) in water.
Experimental Section
In the case of 35c, which bears two sulfonic acid groups
(Scheme 6), however, a low FQY (12%) and a smaller hyp-
sochromic shift in the absorption and emission spectra is
again found. We attribute this observation to the lower abili-
ty of two sulfonic acid groups—relative to four sulfonic acid
groups (Figure 2) or to positively charged pyridinium salts—
to solubilize the PDI chromophore. In this regard, com-
pound 9 with four sulfonic acid substituents has a higher sol-
ubility in water (Figure 2) and, therefore, significantly in-
creased FQYs relative to 35c, indicating a lower tendency
to form aggregates in the case of 9.
Materials: Tetrahydrofuran (Fluka) was distilled over sodium/benzophe-
none. Tetrabutylammonium fluoride (Fluka), di(triphenylphosphine)di-
chloropalladium(ii) (Strem), trimethylethyne (Aldrich), phenol (Aldrich),
3-pyridiniumboronic acid (Lancaster), copper iodide (Aldrich), p-iodo-
phenol (Avocado), and m-xylene (Aldrich), were used as obtained. Tetra-
chloroperylenetetracarboxylic acid diimides and dibromoperylenedianhy-
dride were supplied by BASF AG. Column chromatography was per-
formed with dichloromethane (chromasolv, Riedel) or toluene on silica
gel (Geduran Si60, Merck). All the reported yields are isolated yields.
1
Physical and analytical methods: H and 13C NMR spectra were recorded
on Bruker AMX 250 and Bruker AC 300 spectrometers with use of the
residual proton resonance of the solvent or the carbon signal of the deu-
terated solvent as the internal standard. Chemical shifts are reported in
parts per million. Infrared spectra were obtained on a Nicolet FT IR 320.
For 13C j-modulated spin-echo NMR measurements, the abbreviation q
represents quaternary C atoms and CH2, while t denotes CH3 and CH
groups. FD mass spectra were performed with a VG-Instruments ZAB 2-
SE-FDP instrument. MALDI-TOF mass spectra were measured with a
Bruker Reflex II machine in THF and dithranol as matrix (molar ratio di-
thranol/sample 250:1). The mass peaks with the lowest isotopic mass are
reported. UV/Vis absorption spectra were recorded on a Perkin Elmer
Lambda 40 spectrophotometer, photoluminescence spectra on a SPEX
Fluorolog 3 spectrometer. The quantum yields of polyphenylene-
dendronized perylenes were measured against perylene in toluene as a
reference. The elemental analyses were carried out at the Microanalytical
Laboratory at the University of Mainz (Germany).
Conclusion
In the course of this work we have presented different syn-
thetic approaches towards fluorescent, water-soluble peryle-
netetracarboxylic acid diimide chromophores. The introduc-
tion of hydrophilic substituents onto the bay region of the
chromophore results in a loss in planarity of the aromatic
scaffold, and water-soluble chromophores displaying low to
moderate FQYs (7%–75%) were obtained. The distance
between such hydrophilic groups and the chromophore scaf-
fold was then increased to suppress fluorescence quenching
due to photoinduced electron-transfer processes. However,
attachment of a short alkyl or phenyl spacer was accompa-
N,N’-Bis(2,6-diisopropylphenyl)-1,6,7,12-tetra-[4-(acetic acid)phenoxy]-
perylene-3,4:9,10-tetracarboxylic acid diimide (5): N,N’-Bis(2,6-diisopro-
pylphenyl)-1,6,7,12-tetrachloroperylene-3,4:9,10-tetracarboxylic acid di-
imide (3, 5 g, 5.9 mmol) was treated with methyl (4-hydroxyphenyl)ace-
tate (5 g, 30 mmol) and K2CO3 (4.1 g, 30 mmol) in N-methyl-pyrrolidone
Chem. Eur. J. 2004, 10, 5297 – 5310
www.chemeurj.org
ꢀ 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
5305

K. Müllen et al.
FULL PAPER
(250 mL). The reaction mixture was heated under argon atmosphere for
16 h. The reaction mixture was then allowed to allowed to cool to room
temperature, and dilute hydrochloric acid (500 mL) was added. A precip-
itate was formed and was filtered off, washed with water to neutral pH,
and dried under vacuum. The crude product was then purified by column
chromatography on silica gel with a dichloromethane/acetone (100:5) sol-
vent mixture. Yield: 6.3 g (82%) as a red solid; m.p. >3008C; 1H NMR
(250 MHz, C2D2Cl4, 300 K): d = 8.15 (s, 4H), 7.89 (d, 3J = 8.8 Hz, 8H),
= 164.9, 157.6, 155.9, 147.2, 134.5, 133.7, 132.1, 131.9, 129.9, 125.0, 123.9,
122.1, 122.0, 121.3, 120.7, 68.4, 54.1, 40.2, 30.3 (CH isopropyl), 29.8, 24.1
(CH3 isopropyl) ppm; IR (KBr): n˜ = 2961, 2362, 2336, 1698, 1660, 1587,
1501, 1409, 1339, 1285, 1206, 1174, 965, 911, 877, 842, 741, 673, 549 cmÀ1
;
UV/Vis (methanol): lmax (e)
= 444 (14216), 539 (24361), 577 nm
(29295mÀ1 cmÀ1); fluorescence (methanol, excitation: 550 nm): lmax
=
613 nm; elemental analysis calcd (%) for C92H106N6O8I4: C 57.21, H 5.53,
N 4.35; found: C 57.31, H 5.56, N 4.07.
3
3
3
7.35 (t, J = 8.0 Hz, 2H), 7.19 (d, J = 8.0 Hz, 4H), 6.95 (d, J = 8.8 Hz,
Compound 12b: Ionic perylene derivative 12a (200 mg, 0.103 mmol) and
silver methanesulfonate (83 mg, 0.412 mmol) were added to methanol
(50 mL). The reaction mixture was stirred for 3 h at room temperature.
The white silver iodide was filtered off under vacuum to give a clear red
solution. After the solvent had been removed under vacuum, 12b
(180 mg, 97%) was obtained as a dark red solid. M.p. 2808C; 1H NMR
(250 MHz, CD3CN, 300 K): d = 8.02 (s, 4H), 7.45 (t, 3J = 8.0 Hz, 2H),
7.30 (m, 12H), 6.99 (d, 3J = 8.0 Hz, 8H), 3.64 (m, 8H), 3.15 (s, 36H;
CH3 N-methyl) 3.10 (m, 4H), 2.72 (m, 4H; CH isopropyl), 2.43 (s, 12H;
À
8H), 3.81 (s, 8H), 2.59 (sept, 3J = 6.9 Hz, 4H), 1.03 (d, 3J = 6.9 Hz,
24H) ppm; 13C NMR (75 MHz, C2D2Cl4, 300 K): d
= 166.41 (C=O),
163.07 (C=O), 159.39, 155.32, 145.70, 133.33, 132.23, 130.40, 129.78,
126.65, 124.28, 123.53, 121.44, 121.31, 119.62, 52.66, 29.34, 24.44 ppm; IR
(KBr): n˜ = 2961, 2361, 2336, 1720, 1674, 1592, 1501, 1435, 1406, 1339,
1310, 1275, 1206, 1162, 1109, 1014, 960, 876, 848, 762 cmÀ1; UV/Vis
(CHCl3): lmax (e) = 529 (33300), 564 nm (50000mÀ1 cmÀ1); fluorescence
(CHCl3, excitation: 529 nm): lmax = 620 nm; MS (FD 8 kV): m/z (%):
1312.9 (100) [M]+; elemental analysis calcd (%) for C80H66N2O16: C
73.27, H 5.07, N 2.14; found: C 73.23, H 5.13, N 2.11.
S CH3), 1.05 (d, 3J
=
7.5 Hz, 24H; CH3 isopropyl) ppm; 13C NMR
(75 MHz, CD3CN, 343 K): d = 164.6, 157.1, 155.9, 147.5, 134.5, 133.7,
132.5, 132.0, 130.7, 125.2, 124.5, 121.9, 121.7, 120.9, 68.0, 54.5, 40.2, 30.1
(CH isopropyl), 29.5, 24.3 (CH3 isopropyl) ppm; IR (KBr): n˜ = 2963,
2361, 2336, 1701, 1662, 1589, 1502, 1409, 1340, 1284, 1204, 1052, 912, 877,
Compound 9: N,N’-Bis(2,6-diisopropylphenyl-1,6,7,12-tetraphenoxypery-
lene-3,4:9,10-tetracarboxylic acid diimide (2 g, 1.8 mmol) was added to
concentrated sulfuric acid (5 mL). The flask was sealed, and the mixture
was stirred at room temperature for 15 h. Water (7 mL) was slowly
added to the flask to form a precipitate, which was filtered under suction.
The solid was washed three times with dichloromethane (50 mL), and
was then dried at 1208C under vacuum to give a red product (2.4 g,
93%). M.p. >3008C; 1H NMR (300 MHz, CD3OD, 300 K): d = 7.91 (s,
4H), 7.59 (d, 3J = 8.0 Hz, 8H), 7.17 (t, 3J = 7.5 Hz, 2H), 7.04 (d, 3J =
781, 672, 558 cmÀ1; UV/Vis (H2O): lmax (e)
= 460 (13537), 586 nm
(35436mÀ1 cmÀ1); fluorescence (H2O, excitation: 540 nm): lmax = 627 nm;
elemental analysis calcd (%) for C96H118N6O20S4: C 63.91, H 6.59, N 4.66;
found: C 63.24, H 6.64, N 4.61.
Compound 16: N,N’-Bis(2,6-diisopropylphenyl)-1,6,7,12-tetrachloropery-
lene-3,4:9,10-tetracarboxylic acid diimide (5 g, 5.9 mmol), 3-hydroxypyri-
dine (4.48 g, 47.2 mmol), and anhydrous K2CO3 (3.45 g, 25 mmol) were
added to NMP (600 mL). The solution was stirred at 1008C under argon
for 15 h. The reaction mixture was allowed to cool to room temperature
and poured into aqueous hydrochloride acid (1 L, 1m). The precipitated
product was filtered under suction and was then washed thoroughly with
water and dried at 758C under vacuum. The product was purified by
column chromatography to give 16 (4.7 g, 74%) as a red solid. M.p.
8.0 Hz, 4H), 6.88 (d, 3J = 8.0 Hz, 8H), 2.45 (m, 4H), 0.85 (d, 3J
=
6.75 Hz, 24H) ppm; 13C NMR (75 MHz, CD3OD, 300 K): d = 164.1 (C=
O), 158.5, 156.9, 147.2, 142.4, 131.8, 129.4, 125.0, 124.4, 122.3, 121.8,
120.7, 30.2 (CH isopropyl), 24.2 (CH3 isopropyl) ppm; IR (KBr): n˜
=
2970, 2361, 1701, 1655, 1588, 1491, 1410, 1340, 1287, 1208, 1180, 1125,
1066, 1032, 1007, 882, 846, 699, 580 cmÀ1; UV/Vis (H2O): lmax (e) = 461
(10708), 541 (21026), 571 nm (27800mÀ1 cmÀ1); fluorescence (H2O, exci-
tation 560 nm): lmax = 619 nm; MS (MALDI-TOF): m/z (%): 1401 (%)
[M]+ (calcd 1401).
1
3
>3008C; H NMR (250 MHz, C2D2Cl4, 300 K): d = 8.29 (d, J = 6.3 Hz,
4H), 8.28 (s, 4H), 8.14 (s, 4H), 7.35 (t, 3J = 7.5 Hz, 2H), 7.29 (m, 4H),
7.19 (d, 3J = 8.0 Hz, 4H), 7.17 (d, 3J = 8.0 Hz, 4H), 2.58 (m, 4H), 1.03
(d, 3J = 6.75 Hz, 24H) ppm; 13C NMR (75 MHz, C2D2Cl4, 300 K): d =
162.9 (C=O), 155.5, 152.0, 146.3, 145.6, 141.9, 133.5, 130.2, 129.8, 127.3,
124.9, 123.6, 121.4, 121.1, 120.5, 94.2, 29.3 (CH isopropyl), 24.4 (CH3 iso-
propyl) ppm; IR (KBr): n˜ = 3061, 2963, 2868, 2361, 1707, 1671, 1593,
1508, 1474, 1423, 1407, 1339, 1309, 1279, 1207, 1102, 1019, 958, 875, 808,
738, 705, 581 cmÀ1; UV/Vis (methanol): lmax (e) = 526 (30500), 560 nm
Compound 11: Tetrachloroperylenetetracarboxylic acid diimide (2 g,
2.32 mmol) was stirred under argon with 4-(2-dimethylaminoethyl)phenol
hydrochloride acid salt (2.36 g, 11.8 mmol) in NMP (200 mL) in a 500 mL
round flask in the presence of powdered anhydrous K2CO3 (2 g,
14.4 mmol). The temperature was kept at 1008C under argon overnight.
The reaction mixture was allowed to cool to room temperature and was
then poured into aqueous hydrochloride acid (2n). The precipitated
product was filtered under suction and then washed thoroughly with
water and dried at 758C under vacuum. The product, a red solid, was pu-
rified by column chromatography to provide 5 (1.9 g, 62%) as a dark
(44800mÀ1 cmÀ1); fluorescence (methanol, excitation: 526 nm): lmax
610 nm; MS (FD 8 kV): m/z (%): 1083.2 (%) [M]+ (calcd 1083.1).
=
Compound 17a: N,N’-Bis(2,6-diisopropylphenyl)-1,6,7,12-tetra(3-pyridoxy)-
perylene-3,4:9,10-tetracarboxylic acid diimide (1 g, 0.92 mmol) was dis-
solved in methanol (100 mL), and the mixture was heated at 808C.
Methyl iodide (655 mg, 4.6 mmol) was then added by syringe with vigo-
rous stirring. After 12 h, the solvent was evaporated under vacuum and
the product was dried at 758C. Yield: 1.5 g (96%) as a dark red solid;
M.p. >3008C; 1H NMR (250 MHz, CD3OD, 300 K): d = 8.94 (s, 4H),
8.54 (d, 3J = 6.0 Hz, 4H), 8.38–8.28 (m, 8H), 7.95–7.90 (m, 4H), 7.34 (t,
1
solid. M.p. 2088C; H NMR (250 MHz, CD2Cl2, 300 K): d = 8.17 (s, 4H),
3
3
3
7.46 (t, J = 7.5 Hz, 2H), 7.30 (d, J = 7.5 Hz, 4H), 7.30 (d, J = 8.0 Hz,
8H), 6.90 (d, 3J = 8.0 Hz, 8H), 2.85–2.66 (m, 12H), 2.45 (m, 8H), 2.25
(s, 24H), 1.08 (d, 3J
=
8.0 Hz, 24H; CH3 isopropyl) ppm; 13C NMR
(62.5 MHz, CD2Cl2, 300 K): d = 163.7, 156.3, 153.8, 146.3, 137.5, 133.5,
131.4, 130.5, 129.7, 124.3, 123.1, 121.1, 120.4, 120.1, 61.7, 45.5, 33.7, 29.4
(CH isopropyl), 24.0 (CH3 isopropyl) ppm; IR (KBr): n˜ = 2961, 2864,
2815, 2768, 2361, 1705, 1672, 1587, 1501, 1462, 1406, 1340, 1309, 1284,
1201, 1051, 1015, 958, 877, 825, 737, 675, 537 cmÀ1; UV/Vis (CHCl3): lmax
(e) = 456 (18189), 539 (30196), 577 nm (48744mÀ1 cmÀ1); MS (FD 8 kV):
m/z (%): 1363.2 (%) [M]+ (calcd 1363.7); elemental analysis calcd (%)
for C88H94N6O8: C 77.50, H 6.95, N 6.16; found: C 76.94, H 6.76, N 6.04.
3
3
3J = 8.2 Hz, 4H), 7.91 (d, J = 8.2 Hz, 4H), 4.30 (s, 12H), 2.73 (sept, J
= 6.9 Hz, 4H), 0.97 (d, 3J = 6.9 Hz, 24H) ppm; 13C NMR (75 MHz,
CH3OH-D4, 300 K): d = 164.06 (C=O), 157.02, 154.95, 147.04, 142.99,
139.44, 135.93, 134.19, 131.42, 130.94, 130.29, 126.13, 125.22, 124.53,
124.23, 123.60, 39.54, 30.32, 24.32 ppm; IR (KBr): n˜ = 2963, 2361, 2336,
1704, 1665, 1594, 1503, 1473, 1408, 1337, 1309, 1275, 1212, 812, 672 cmÀ1
;
Compound 12a: Perylene derivative 12 (1 g, 0.73 mmol) and methyl
iodide (2 mL) in chloroform (100 mL) were placed in a 250 mL round
flask. The reaction mixture was heated to 608C for 1 hour, resulting in
the formation of a dark precipitate. After the chloroform had been re-
moved, the residue was dissolved in methanol (20 mL) containing methyl
iodide (3 mL). The solution was stirred at 708C for 24 h. The solvent and
the excess methyl iodide were removed under vacuum to give a dark red
solid. The product 12a (1.3 g, 93%) was obtained after drying at 758C
under vacuum. M.p. >3008C; 1H NMR (300 MHz, CD3CN, 343 K): d =
8.08 (s, 4H), 7.45 (t, 3J = 7.5 Hz, 2H), 7.34 (m, 12H), 7.06 (d, 3J =
7.5 Hz, 8H), 3.62 (m, 8H), 3.20 (s, 36H), 3.13 (m, 8H), 2.75 (m, 4H),
UV/Vis (H2O): lmax (e) = 520 (19300), 555 nm (25700mÀ1 cmÀ1); fluores-
cence (H2O, excitation: 520 nm): lmax = 601 nm; elemental analysis calcd
(%) for C72H66I4N6O8: C 52.38, H 4.03, N 5.09; found: C 52.41, H 4.00, N
5.11.
Compound 17b: Perylene derivative 17 (1 g, 0.92 mmol), methyl iodide
(3 mL), and methanol (150 mL) were placed in a 250 mL flask. The reac-
tion mixture was stirred at 808C for 24 h. After the reaction mixture had
been allowed to cool to room temperature, the solvent was removed
under vacuum. The residue and silver methanesulfonate (743 mg,
3.68 mmol) were added to methanol (100 mL) to form a white precipitate
(silver iodide), which was removed to give a clear red solution. A red
3
1.09 (d, J = 7.0 Hz, 24H) ppm; 13C NMR (75 MHz, CD3OD, 328 K): d
5306
ꢀ 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
Chem. Eur. J. 2004, 10, 5297 – 5310

Fluorescent Water-Soluble Perylene Dyes
5297 – 5310
solid (1.4 g, 91%) was obtained after evaporation of the solvent. M.p.
2648C; 1H NMR (300 MHz, CD3OD, 300 K): d = 8.95 (m, 4H), 8.66 (d,
3J = 6.0 Hz, 4H), 8.31 (s, 4H), 8.27 (m, 4H), 7.97 (d, 3J = 7.5 Hz, 2H),
147.5, 147.2, 143.6, 136.6, 134.5, 131.8, 130.7, 129.7, 125.0, 124.1, 122.4,
À
121.8, 121.7, 121.5, 58.1 (N CH3), 30.3 (CH isopropyl), 25.2 (CH3 isopro-
pyl) ppm; IR (KBr): n˜ = 2959, 2361, 2336, 1700, 1660, 1589, 1490, 1406,
1336, 1309, 1278, 1204, 1171, 1119, 1003, 955, 873, 825, 737, 551 cmÀ1
;
3
3
3
7.94 (d, J = 7.5 Hz, 2H), 7.38 (t, J = 7.5 Hz, 2H), 7.23 (d, J = 7.5 Hz,
À
4H), 4.34 (s, 12H), 2.61 (m, 2H; CH isopropyl), 2.46 (s, 12H; S CH3),
UV/Vis (methanol): lmax (e)
= 446 (22044), 537 (34082), 575 nm
1.08 (d, 3J
=
6.5 Hz, 12H; CH3 isopropyl) ppm; 13C NMR (75 MHz,
(52404mÀ1 cmÀ1); fluorescence (methanol, excitation: 550 nm): lmax
=
614 nm; elemental analysis calcd (%) for C108H106N6O8: C 61.08, H 5.03,
N 3.96; found: C 60.69, H 5.26, N 3.73.
CD3OD, 300 K): d = 164.0 (C=O), 157.0, 154.9, 127.0, 142.9, 139.4, 135.9,
134.1, 131.4, 130.9, 130.2, 126.1, 125.2, 124.5, 124.2, 123.5, 39.5, 30.3,
24.3 ppm; IR (KBr): n˜ = 3432, 2946, 2361, 2336, 1705, 1664, 1595, 1502,
1408, 1335, 1310, 1274, 1200, 1052, 957, 814, 780, 671, 558 cmÀ1; UV/Vis
(H2O): lmax (e) = 434 (9766), 516 (24628), 547 nm (33751mÀ1 cmÀ1); fluo-
rescence (H2O, excitation: 540 nm): lmax = 588 nm; elemental analysis
calcd (%) for C76H78N6O20S4: C 59.91, H 5.16, N 5.52; found: C 59.54, H
5.32, N 5.47.
Compound 23b: Ionic perylene derivative 23a (400 mg, 0.188 mmol) and
silver methanesulfonate (152 mg, 0.754 mmol) were added to methanol
(50 mL). The reaction mixture was stirred for 3 h at room temperature.
The white silver iodide was filtered off under vacuum to give a clear red
solution. After the solvent had been removed under vacuum, 23b
1
(345 mg, 92%) was obtained as a dark red solid. M.p. >3508C; H NMR
(250 MHz, CD3OD, 300 K): d = 8.16 (s, 4H), 7.86 (d, 3J = 9.5 Hz, 8H),
Compound 21: 4-(Dimethylamino)phenylboronic acid 19 (1 g, 6 mmol),
tetrabromoperylenediimide 18 (2.8 g, 2 mmol), and toluene (120 mL)
were placed in a 250 mL Schlenk flask. Aqueous K2CO3 (30 mL, 1m),
ethanol (20 mL), and [Pd(PPh3)4] (400 mg, 0.25 mmol) were then added
to the flask under argon. After 16 h at 808C, the reaction mixture was al-
lowed to cool to room temperature. The organic phase was separated
and dried under vacuum. The crude material was purified by column
chromatography on silica to give 2 (2.86 g, 92%). M.p. >3008C; 1H
NMR (250 MHz, CD2Cl2, 300 K): d = 8.29 (s, 4H), 7.47 (m, 18H), 7.30
(d, 3J = 7.5 Hz, 4H), 7.07 (dd, 3J = 8.0 Hz, 8H), 6.77 (d, 3J = 8.0 Hz,
8H), 2.97 (s, 24H; CH3 N-methyl) 2.72 (m, 4H; CH isopropyl), 1.09 (d,
3J = 7.5 Hz, 24H; CH3 isopropyl) ppm; 13C NMR (62.5 MHz, CD2Cl2,
300 K): d = 164.6, 157.2, 155.0, 151.0, 146.8, 139.1, 134.5, 131.8, 130.7,
129.5, 129.1, 125.3, 123.9, 122.1, 121.7, 121.6, 121.4, 113.9, 41.88, 30.4 (CH
isopropyl), 25.5 (CH3 isopropyl) ppm; IR (KBr): n˜ = 2962, 2361, 1701,
1668, 1611, 1585, 1495, 1407, 1338, 1290, 1202, 1166, 946, 884, 808, 733,
525 cmÀ1; UV/Vis (CHCl3) lmax (e) = 441 (16085) 553 (33223), 592 nm
(38674mÀ1 cmÀ1); MS (FD 8 kV): m/z (%) = 1555.1 (%) [M]+ (calcd
1555.8); elemental analysis calcd (%) for C104H94N6O8: C 80.28, H 6.09, N
5.40; found: C 79.54, H 5.96, N 5.33.
3
3
3
7.71 (d, J = 9.0 Hz, 8H), 7.56 (d, J = 8.5 Hz, 8H), 7.30 (t, J = 8.5 Hz,
2H), 7.17 (m, 12H), 3.58 (s, 24H; CH3 N-methyl) 2.60 (m, 4H; CH iso-
propyl), 2.56 (s, 12H; S CH3), 1.09 (d, 3J = 7.5 Hz, 24H; CH3 isopro-
À
pyl) ppm; 13C NMR (75 MHz, CD3OD, 300 K): d = 164.8, 157.3, 157.1,
147.5, 147.1, 143.5, 136.6, 134.5, 131.7, 130.7, 130.1, 129.7, 125.1, 124.0,
À
À
122.3, 122.0, 121.7, 121.6, 121.2, 57.7 (N CH3), 39.5 (S CH3), 30.3 (CH
isopropyl), 25.2 (CH3 isopropyl) ppm; IR (KBr): n˜ = 2962, 2361, 1701,
1668, 1611, 1585, 1495, 1407, 1338, 1290, 1202, 1166, 946, 884, 808, 733,
525 cmÀ1; UV/Vis (H2O): lmax (e) = 491 (17088) 554 (24621), 565 nm
(27454mÀ1 cmÀ1); fluorescence (DMSO, excitation: 520 nm): lmax
=
614 nm; elemental analysis calcd (%) for C108H106N6O8: C 67.38, H 5.96,
N 4.21; found: C 67.11, H 5.99, N 4.12.
Compound 24a: Perylene derivative 22 (400 mg, 0.28 mmol), methyl
iodide (3 mL), acetone (30 mL), and methanol (100 mL) were placed in a
250 mL flask. The reaction mixture was stirred at 708C for 20 h. The sol-
vent was removed under vacuum after having been allowed to cool to
room temperature. The residue was dissolved in methanol (100 mL), and
methyl iodide (2 mL) was added. The solution was stirred at 808C for
24 h. The solvent was removed, and the residue was dried under vacuum
at 758C to give 24a (380 mg, 91%) as a brown solid. M.p. 3538C; 1H
NMR (250 MHz, CD3OD, 300 K): d = 9.18 (s, 2H), 8.95 (s, 2H), 8.71–
8.56 (m, 8H), 8.17 (s, 4H), 7.95 (m, 2H), 7.88 (q, 2H), 7.79–7.68 (m,
8H), 7.33 (t, 3J = 8.5 Hz, 2H), 7.28–7.18 (m, 12H), 4.36 (s, 6H), 4.34 (s,
6H), 2.61 (m, 4H; CH isopropyl), 1.00 (d, 3J = 6.75 Hz, 24 H CH3 iso-
propyl) ppm; IR (KBr): n˜ = 3029, 2961, 2361, 2336, 1695, 1660, 1588,
1492, 1406, 1338, 1283, 1211, 1173, 959, 878, 844, 809, 738, 675, 566,
Compound 22: N,N’-Bis(2,6-diisopropylphenyl-1,6,7,12-tetra(4-bromo-
phenoxy)perylene-3,4:9,10-tetracarboxylic acid diimide (1.3 g, 1 mmol),
3-pyridinium boronic ester (1 g, 6.2 mmol), and toluene (60 mL) were
placed in a 250 mL Schlenk flask. Pd(PPh3)4 (200 mg, 0.16 mmol), aque-
ous K2CO3 (20 mL, 1m), and ethanol (10 mL) were then added to the
flask under argon. After 16 h at 808C, the reaction mixture was allowed
to cool to room temperature. The organic phase was separated and dried
under vacuum. The crude material was purified by column chromatogra-
phy on silica to give 22 (1.16 g, 84%). M.p. 2818C; 1H NMR (250 MHz,
CD2Cl2, 300 K): d = 8.76 (d, 3J = 1.5 Hz, 4H), 8.53 (dd, 3J = 5.0 Hz,
4H), 8.35 (s, 4H), 7.82 (t, 3J = 1.5 Hz, 2H), 7.79 (t, 3J = 1.5 Hz, 2H),
529 cmÀ1; UV/Vis (methanol): lmax (e)
= 442 (17257), 529 (24447),
567 nm (37151mÀ1 cmÀ1); fluorescence (methanol, excitation: 540 nm):
lmax = 606 nm.
Compound 24b: Ionic perylene derivative 24a (100 mg, 0.051 mmol) and
silver methanesulfonate (46 mg, 0.21 mmol) were added to methanol
(50 mL). The reaction mixture was stirred for 15 h at room temperature.
The white silver iodide was filtered off under vacuum to give a clear red
solution. After the solvent had been removed under vacuum, 24b (85 mg,
3
3
7.54 (dd, J = 8.0 Hz, 8H), 7.45 (d, J = 7.5 Hz, 2H), 7.32 (m, 8H), 7.14
(d, J = 7.5 Hz, 8H), 2.72 (m, 2H; CH isopropyl), 1.10 (d, 3J = 6.75 Hz,
3
12H; CH3 isopropyl) ppm; 13C NMR (62.5 MHz, CD2Cl2, 300 K): d =
163.6 (q, C=O), 156.0 (q), 148.8 (t), 148.4 (t), 146.3 (q), 135.9 (q), 134.8
(q), 134.4 (t), 133.6 (q), 131.3 (q), 129.9 (t), 129.2 (t), 124.4 (t), 123.9, (t),
123.5 (q), 121.5 (q), 121.2 (q), 121.1 (t), 120.7 (t), 29.5 (t), 24.1 (t) ppm;
IR (KBr): n˜ = 3031, 2961, 2867, 2361, 2336, 1705, 1669, 1589, 1504, 1472,
1405, 1337, 1307, 1279, 1208, 1172, 1000, 957, 876, 842, 803, 739, 711, 674,
552 cmÀ1; UV/Vis (CHCl3): lmax (e) = 448 (19864), 534 (30794), 574 nm
1
94%) was obtained as a dark red solid. M.p. 2438C; H NMR (250 MHz,
3
3
CD3OD, 300 K): d = 9.16 (s, 4H), 8.73 (d, J = 6.0 Hz, 4H), 8.66 (d, J
= 8.2 Hz, 4H), 8.16 (s, 4H), 8.00 (m, 4H), 7.76 (d, 3J = 8.75 Hz, 8H),
7.34 (t, J = 8.5 Hz, 2H), 7.28 (d, J = 8.5 Hz, 8H), 7.21 (d, J = 7.7 Hz,
3
3
3
À
4H), 4.35 (s, 12H), 2.61 (m, 4H; CH isopropyl), 2.57 (s, 12H; S CH3),
(50105mÀ1 cmÀ1); fluorescence (CHCl3, excitation 540: nm): lmax
=
1.00 (d, 3J = 6.7 Hz, 24H; CH3 isopropyl) ppm; 13C NMR (62.5 MHz,
CD3OD, 300 K): d = 164.9 (q, C=O), 159.0 (q), 157.3 (q), 147.4 (q),
145.2 (t), 145.0 (t), 143.9 (t), 141.8 (q),134.8 (q),132.0 (q),131.5 131.1 (t),
606 nm; MS (FD 8 kV): m/z (%): 1387.9 (%) [M]+ (calcd 1387.6); ele-
mental analysis calcd (%) for C92H70N6O8: C 79.63, H 5.08, N 6.06;
found: C 79.59, H 5.20, N 6.01.
À
129.4 (t), 125.4 (t), (q),124.7 (q), 122.7 (t), 122.4 (q), 121.9 (t), 39.8 (t, S
CH3), 30.7 (t, CH isopropyl), 24.6 (t, CH3 isopropyl) ppm; IR (KBr): n˜ =
3025, 2923, 2792, 2360, 1707, 1674, 1613, 1522, 1500, 1438, 1403, 1338,
1277, 1199, 1165, 1129, 1069, 1018, 946, 875, 822, 754, 699, 558 cmÀ1; UV/
Vis (H2O): lmax (e) = 459 (19225), 578 nm (25855mÀ1 cmÀ1); fluorescence
(H2O, excitation: 540 nm): lmax = 624 nm.
Compound 23a: Perylene derivative 18 (1 g, 0.64 mmol) and methyl
iodide (2 mL) in methanol (100 mL) were placed in a 250 mL round
flask. The reaction mixture was heated to 608C for 1 hour, resulting in
the formation of a dark precipitate. After chloroform had been removed,
the residue was dissolved in methanol (20 mL) containing methyl iodide
(3 mL). The solution was stirred at 808C for 24 h. The solvent and the
excess methyl iodide were removed under vacuum. The residue was
dried at 758C under vacuum to give 23a (1.2 g, 92%) as a violet solid.
M.p. >3008C; 1H NMR (250 MHz, CD3OD, 300 K): d = 8.16 (s, 4H),
Compound 26: 1,3-Diphenylacetone (4.3 g, 20 mmol), 4,4’-bis(dimethyla-
mino)benzyl (6 g, 20 mmol), and EtOH (100 mL) were placed in
a
250 mL round flask. The solution was heated to 828C, and potassium hy-
droxide (1.12 g, 20 mmol) in EtOH (20 mL) was then injected into the
flask under argon. After the mixture had been stirred at 828C for 15 h, it
was allowed to cool to room temperature. The solution was filtered to
give a yellow solid, which was washed three times with ethanol (100 mL).
The product was obtained by column chromatography (2.9 g, 31%). M.p.
3
3
3
7.90 (d, J = 8.0 Hz, 8H), 7.70 (d, J = 8.0 Hz, 8H), 7.54 (d, J = 8.0 Hz,
8H), 7.29 (t, 3J = 8.0 Hz, 2H), 7.17 (m, 12H), 3.61 (s, 36H; CH3 N-
3
methyl) 2.60 (m, 4H; CH isopropyl), 0.99 (d, J = 7.5 Hz, 24H; CH3 iso-
propyl) ppm; 13C NMR (75 MHz, CD3OD, 323 K): d
= 164.9, 157.2,
Chem. Eur. J. 2004, 10, 5297 – 5310
www.chemeurj.org
ꢀ 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
5307

K. Müllen et al.
FULL PAPER
1
2738C; H NMR (250 MHz, CD2Cl2, 300 K): d = 7.24 (m, 10H), 6.81 (d,
125.18, 121.02, 120.54, 120.35, 29.85 (CH isopropyl), 24.21 (CH3 isopro-
pyl) ppm; IR (KBr): n˜ = 3060, 3032, 2967, 2945, 2872, 1708, 1674, 1594,
1501, 1446, 1406, 1338, 1317, 1287, 1206, 1181, 1141, 957, 842, 764,
698 cmÀ1; UV/Vis (toluene): lmax (e) = 362 (64807), 543 (22368), 583 nm
3J = 8.5 Hz, 4H), 6.50 (d, J = 8.5 Hz, 4H), 2.95 (s, 12H; CH3) ppm; 13C
3
NMR (62.5 MHz, CD2Cl2, 300 K): d = 200.5 (C=O), 155.2, 150.7, 132.8,
131.5, 130.6, 128.1, 127.0, 124.0, 111.11, 40.2 (CH3) ppm; IR (KBr): n˜ =
2923, 2798, 2361, 1689, 1603, 1517, 1490, 1442, 1355, 1309, 1228, 1197,
1169, 1116, 944, 896, 823, 765, 735, 699, 536 cmÀ1; MS (FD 8 kV): m/z
(%): 470.3 (%) [M]+ (calcd 470.6); elemental analysis calcd (%) for
C33H30N2O: C 84.22, H 6.43, N 5.95; found: C 84.15, H 6.48, N 6.01.
(33679mÀ1 cmÀ1); fluorescence (toluene, excitation: 583 nm): lmax
=
607 nm; MS (MALDI-TOF): m/z (%): 4036 (%) [M]+, (calcd 4035); ele-
mental analysis calcd (%) for C296H210N10O8: C 88.11, H 5.25, N 3.47;
found: C 87.85, H 5.39, N 3.40.
Compound 27:
A
mixture of ethynyl-substituted perylenediimide 25
Compound 31a: Compound 30a (500 mg, 0.124 mmol) was dissolved in
THF (7 mL) under argon atmosphere, and degassed hydrochloric acid
(5m, 15 mL) was added. The reaction mixture was stirred under argon at
room temperature for 2 h. The precipitate was filtered off and washed
with hexane. Yield: 315 mg (0.117 mmol, 94%) as a violet solid. M.p.
>3008C; 1H NMR (300 MHz, d8-THF, 298 K): d = 8.05 (s, 4H; Hbay-p.),
7.78–6.79 (m, 98H; arom. H), 2.78 (sept, 3J = 6.68 Hz, 4H; CH isopro-
(100 mg, 0.085 mmol) and tetraphenylcyclopentadienone derivative 26
(200 mg, 0.425 mmol) in m-xylene (5 mL) was stirred at 1408C under
argon for 15 h. The cooled reaction mixture was poured into methanol
(100 mL). The precipitated product was filtered under suction. Finally,
the product was dried and purified by column chromatography on silica
gel to give a dark red solid. Yield: 230 mg (92%). M.p. >3008C; 1H
NMR (250 MHz, CD2Cl4, 300 K): d = 8.13 (s, 4H), 7.48 (m, 6H), 7.33
(d, 3J = 7.5 Hz, 4H), 7.15 (m, 20H), 7.03 (d, 3J = 8.0 Hz, 8H), 6.94 (m,
8H), 6.83 (m, 12H), 6.71 (d, 3J = 8.0 Hz, 8H), 6.66 (d, 3J = 8.0 Hz,
pyl), 1.18 (d, 3J
=
6.49 Hz, 24H; CH3 isopropyl) ppm; 13C NMR
(75 MHz, [D8]THF, 298 K): d = 199.75, 156.42, 155.81, 140.02, 135.55,
134.94, 133.52, 133.12, 132.42, 132.14, 130.67, 130.28, 130.16, 130.09,
130.00, 129.67, 129.18, 128.44, 124.11, 123.86, 123.55, 31.56 (CH isopro-
pyl), 25.53 (CH3 isopropyl) ppm; IR (KBr): n˜ = 3433, 3062, 2881, 3593,
2000, 1704, 1660, 1597, 1504, 1447, 1409, 1339, 1318, 1281, 1207, 1178,
841, 761, 703, 638 cmÀ1; UV/Vis (methanol): lmax (e) = 442 (15142), 536
(17016), 572 nm (23069mÀ1 cmÀ1); fluorescence (methanol, excitation:
572 nm): lmax = 611 nm; MS (MALDI-TOF): m/z (%): 2724 (%) [M]+
(calcd 2721).
3
3
16H), 6.34 (d, J = 8.0 Hz, 8H), 6.30 (d, J = 8.0 Hz, 8H), 2.80 (s, 24H),
2.78 (s, 24H), 2.71 (m, 4H; CH isopropyl), 1.12 (d, 3J
=
8.0 Hz,
24H) ppm; 13C NMR (62.5 MHz, CD2Cl2, 300 K): d = 163.6 (q, C=O),
156.1 (q), 154.1 (q), 148.6 (q), 148.4 (q), 146.4 (q), 142.9 (q), 142.5 (q),
141.6 (q), 141.0 (q), 140.4 (q), 140.1 (q), 139.6 (q), 138.9 (q), 133.2 (q),
132.6 (t), 132.5 (t), 132.0 (t), 131.9 (t), 131.5 (q), 131.2 (t), 130.3 (t), 129.8
(t), 129.1 (q), 128.7 (q), 127.8 (t), 127.2 (t), 126.2 (t), 125.8 (t), 124.4 (t),
123.3 (q), 121.2 (q), 121.1 (t), 120.7 (q), 119.2 (t), 111.3 (t), 111.1 (t), 40.5
(t, CH3), 29.4 (t, CH isopropyl), 24.1 (p, CH3 isopropyl) ppm; IR (KBr):
n˜ = 3030, 2961, 2796, 2361, 2336, 1707, 1673, 1611, 1521, 1500, 1441,
1404, 1338, 1278, 1201, 1167, 1016, 946, 821, 698, 544 cmÀ1; UV/Vis
(CHCl3): lmax (e) = 463 (20661), 545 (27993), 585 nm (43834mÀ1 cmÀ1);
Compound 30b: Compounds 25 (150 mg, 0.128 mmol) and 29b (434 mg,
0.683 mmol) were dissolved in o-xylene (9 mL) and diphenyl ether
(3 mL), and the mixture was heated at 1758C under argon atmosphere
for 40 h. The solvent was evaporated and the crude product was dried
under vacuum. Compound 29b was separated by column chromatogra-
phy on silica gel with dichloromethane as eluent, and 25 was eluted from
the column with ethyl acetate. The product was then dissolved in di-
chloromethane and precipitated from pentane, filtered, and dried under
vacuum. Yield: 290 mg (0.077 mmol, 60%) as a red solid; m.p.: >3008C;
1H NMR (500 MHz, d8-THF, 323 K): d = 8.15 (s, 4H), 7.96 (t, 3J =
7.63 Hz, 12H; arom. H), 7.64 (s, 4H), 7.34–6.79 (m, 114H; arom. H),
fluorescence (cyclohexane): lmax
= 594 nm (excitation 540 nm); MS
(MALDI-TOF 8 kV): m/z=2945 (%) [M]+ (calcd 2945); elemental anal-
ysis calcd (%) for C208H178N10O8: C 84.81, H 6.09, N 4.75; found: C 84.51,
H 5.88, N 4.90.
Compound 28: Dendronized perylene derivative 27 (200 mg,
0.068 mmol), dimethylsulfate (2 mL), and chloroform (50 mL) were
placed in a 100 mL round flask. The reaction mixture was heated to 758C
for 16 h, resulting in a dark precipitate. After the chloroform had been
removed, the residue was dissolved in methanol (50 mL) and dimethyl-
sulfate (1 mL), and the mixture was maintained at 808C for 48 h. The sol-
vent was removed under vacuum to give a dark oil. Diethyl ether
(100 mL) and dichloromethane (100 mL) were added to the flask to form
3
3
4.31 (q, J = 7.12 Hz, 16H; CH2 ester), 2.80 (sept, J = 6.71 Hz, 4H; CH
3
3
isopropyl), 1.34 (t, J = 7.32 Hz, 24H; CH3 ester), 1.16 (d, J = 6.71 Hz,
24H; CH3 isopropyl) ppm; 13C NMR (125 MHz, d8-THF, 323 K): d =
166.48 (C=O ester), 163.85 (C=O PDI), 157.08, 155.25, 147.03, 145.81,
145.76, 142.92, 142.48, 142.40, 141.69, 141.43, 141.33, 141.10, 140.79,
140.14, 139.49, 138.18, 137.94, 134.20, 133.37, 132.74, 130.98, 130.73,
130.49, 130.44, 128.68, 128.27, 127.35, 126.67, 126.41, 124.48, 124.07,
121.51, 120.31, 119.79, 61.38 (CH2 ester), 30.19 (CH isopropyl), 24.51
(CH3 isopropyl), 14.78 (CH3 ester) ppm; UV/Vis (toluene): lmax (e) =
457 (21429), 542 (31859), 582 nm (50791mÀ1 cmÀ1); fluorescence (tolu-
ene, excitation: 582 nm): lmax = 604 nm; MS (MALDI-TOF): m/z (%):
3787 (100) [M]+; elemental analysis calcd (%) for C264H202N2O24: C 83.74,
H 5.38, N 0.74; found: C 82.59, H 5.69, N 0.77.
a
precipitate, which was washed three times with dichloromethane
(50 mL). The product 28 was obtained after removal of the solvent and
drying under vacuum at 1008C (130 mg, 62%). M.p. >3008C; 1H NMR
3
(250 MHz, CD3OD, 300 K): d = 7.96 (s, 4H), 7.45 (d, J = 7.5 Hz, 10H),
3
3
7.40 (d, J = 7.5 Hz, 10H), 7.25 (d, J = 7.5 Hz, 4H), 7.05 (s, 16H), 7.03
(m, 34H), 6.83 (m, 16H), 6.76 (d, 3J = 7.5 Hz, 8H), 3.36 (s, 24H), 3.42
(s, 36H), 3.38 (s, 36H), 2.61 (m, 4H), 1.03 (d, 3J = 6.7 Hz, 24H) ppm;
13C NMR (125 MHz, [D4]DMSO, 306 K): d = 162.6 (C=O), 155.2, 153.4,
145.5, 145.2, 145.0, 141.5, 141.1, 140.2, 140.1, 139.8, 138.7, 138.6, 137.4,
132.6, 131.4, 131.1, 129.6, 128.0, 127.2, 127.0, 126.3, 123.8, 122.6, 119.9,
Compound 31b: Compound 30b (100 mg, 0.026 mmol) was dissolved in
THF (10 mL) under argon atmosphere. Potassium hydroxide (118 mg,
2.113 mmol) dissolved in distilled water (1 mL) was then added, and the
mixture was flushed with argon. The reaction mixture was heated at
808C for 42 h. After 16 h and 19 h, additional distilled water (1 mL) was
added. The reaction mixture was then allowed to cool to room tempera-
ture, and the precipitate was poured into hydrochloric acid (2m, 150 mL).
The precipitate was filtered and dried at 808C. Yield: 93 mg (0.025 mmol,
À
119.2, 118.9, 118.5, 56.4 (N CH3), 28.4 (CH isopropyl), 23.7 (CH3 isopro-
pyl) ppm; IR (KBr): n˜max = 3030, 2962, 2796, 2361, 1696, 1655, 1592,
1485, 1413, 1341, 1285, 1219, 1127, 1033, 842, 625, 574 cmÀ1; UV/Vis
(H2O): lmax (e) = 463 (17459), 548 (22965), 589 nm (36113mÀ1 cmÀ1);
fluorescence (H2O, excitation 550 nm): lmax = 620 nm; elemental analysis
calcd (%) for C224H226N10O40S8: C 68.03, H 5.76, N 3.54; found: C 67.71,
H 5.92, N 3.57.
98%) as
a
dark violet solid. M.p. >3008C; 1H NMR (500 MHz,
[D6]DMSO, 306 K): d = 12.85 (s, 8H; COOH), 7.94–6.74 (m, 134H;
arom. H), 2.71 (m, 4H; CH isopropyl), 1.04 (s, 24H; CH3 isopro-
pyl) ppm; 13C NMR (125 MHz, [D6]DMSO, 298 K): d = 168.26 (C=O
acid), 163.91 (C=O); 157.89, 156.34, 154.63, 144.44, 142.23, 141.81, 141.32,
140.93, 140.55, 140.36, 139.77, 137.09, 136.79, 133.11, 131.26, 131.09,
130.82, 130.63, 129.00, 127.45, 126.56, 126.19, 124.65, 119.83, 29.64 (CH
isopropyl), 24.97 (CH3 isopropyl) ppm; IR (KBr): n˜ = 3471, 3049, 2968,
1709, 1609, 1593, 1500, 1409, 1339, 1283, 1207, 1178, 1115, 1007, 842, 752,
702, 567 cmÀ1; UV/Vis (DMSO): lmax (e) = 461 (21176), 547 (30013),
584 nm (44408mÀ1 cmÀ1); fluorescence (DMSO, excitation: 584 nm): lmax
= 620 nm; MS (MALDI-TOF): m/z (%): 3562 (%) [M]+, (calcd 3562);
elemental analysis calcd (%) for C248H170N2O24: C 83.62, H 4.81, N 0.79;
found: C 83.48, H 5.26, N 0.80.
Compound 30a: Compounds 25 (220 mg, 0.187 mmol) and 29a (834 mg,
1.12 mmol) were dissolved in o-xylene (15 mL) and were heated at
1708C for 20 h under argon atmosphere. The crude mixture was then
poured into methanol (100 mL), and the precipitate was filtered, washed
several times with methanol, and dried under vacuum. Yield: 670 mg
(0.166 mmol, 89%) as a red solid; m.p. : 2628C (decomp); 1H NMR
(300 MHz, d8-THF, 298 K): d = 8.14 (s, 4H; Hbay-p.), 7.79–6.22 (m, 178H;
arom. H), 2.77 (sept, 3J = 6.96 Hz, 4H; CH isopropyl), 1.13 (d, 3J =
6.32 Hz, 24H; CH3 isopropyl) ppm; 13C NMR (75 MHz, [D8]THF,
298 K): d = 168.83 (C=N), 163.51 (C=O), 154.98, 153.02, 149.74, 149.40,
142.49, 140.32, 140.19, 137.04, 132.37, 132.21, 131.41, 130.84, 130.59,
130.18, 129.98, 129.87, 129.38, 129.11, 128.76, 128.62, 129.39, 127.60,
5308
ꢀ 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
Chem. Eur. J. 2004, 10, 5297 – 5310

Fluorescent Water-Soluble Perylene Dyes
5297 – 5310
3
3
3
Compound 30c Yield: 87 mg (0.01 mmol, 56%) as a red oil; 1H NMR
(500 MHz, [D8]THF, 298 K): d = 8.03 (s, 4H); 7.42–6.63 (m, 86H); 7.13
(s, 16H); 4.03–4.01 (m, 48H); 3.52–3.39 (m, 36H); 3.32–3.31 (m, 72H);
2.75 (sept, 4H); 1.14 (d, 3J = 6.79 Hz, 12H) ppm; UV/Vis (H2O): lmax
(dd, J = 8.5 Hz, 2H), 8.01 (q, 2H), 7.40 (t, J = 8.2 Hz, 2H), 7.26 (d, J
À
= 7.5 Hz, 4H), 4.35 (s, 6H; N CH3), 2.66 (m, 4H; CH isopropyl), 2.55
(s, 6H; S CH3), 1.02 (d, 3J = 7.0 Hz, 24H; CH3 isopropyl) ppm; 13C
À
NMR (62.5 MHz, CD3OD, 300 K): d = 165.1 (q, C=O), 164.4 (q, C=O),
156.8 (q), 153.6 (q), 147.4 (q), 143.0 (t), 138.9 (t), 135.3 (t), 134.7 (q),
133.2 (t), 131.9 (q), 131.5 (q), 131.4 (t), 131.1 (t), 130.6 (t), 128.9 (q),
128.3 (q), 127.2 (t), 126.6 (q), 125.4 (t), 124.6 (q), 49.7 (t), 39.7 (t), 30.7 (t,
CH isopropyl), 24.6 (t, CH3 isopropyl), 24.5 (t, CH3 isopropyl) ppm; IR
(KBr): n˜ = 2961, 2361, 2336, 1705, 1664, 1595, 1504, 1468, 1408, 1339,
1200, 1053, 811, 778, 672, 557, 532 cmÀ1 ; UV/Vis (H2O): lmax (e) = 400
(4535), 503 (13640), 536 nm (19022mÀ1 cmÀ1); fluorescence (H2O, excita-
tion: 520 nm): lmax = 573 nm.
(e)
= 539, 582 nm; fluorescence (H2O, excitation: 582 nm): lmax =
615 nm; MS (MALDI-TOF): m/z (%): 8545 (100) [M]+ (calcd 8543.80).
Compound 34a: 1,6(7)-Dibromoperylenetetracarboxylic acid diimide (32,
2.0 g, 2.3 mmol) was stirred with phenol (1.88 g, 20 mmol) in NMP
(150 mL) under argon at 1008C in a 250 mL round flask in the presence
of powdered anhydrous K2CO3 (1.38 g, 10 mmol). The temperature was
maintained at 1008C for 20 h under argon. The reaction mixture was al-
lowed to cool to room temperature and poured into aqueous hydrochlo-
ric acid (300 mL, 1m). The precipitated product was filtered under suc-
tion, and was then purified by column chromatography to give a red
solid 34a (1.5 g, 75%). M.p. >3008C; 1H NMR (300 MHz, C2D2Cl4,
Compound 35c: Diphenoxyperylenedicarboxylic acid diimide 34b
(300 mg, 0.335 mmol) was added to concentrated sulfuric acid (1 mL).
The flask was sealed, and the mixture was then stirred at room tempera-
ture for 15 h. Water (3 mL) was slowly added to the flask to form a pre-
cipitate, which was filtered off under suction. The solid was washed three
times with dichloromethane (50 mL), and then dried at 758C under
vacuum to give a red product (330 mg, 94%). M.p. 2228C; 1H NMR
3
3
300 K): d = 9.48 (d, J = 8.0 Hz, 2H), 8.64 (d, J = 8.0 Hz, 2H), 8.50 (s,
2H), 8.47 (d, 3J = 8.0 Hz, 2H), 8.26 (s, 2H), 7.57 (m, 2H), 7.42–7.36 (m,
4H), 7.23 (d, 3J = 7.5 Hz, 4H), 2.61 (m, 4H), 1.06 (m, 24H) ppm; 13C
NMR (75 MHz, C2D2Cl4, 300 K): d = 163.4 (C=O), 162.9 (C=O), 154.6,
152.0, 146.6, 145.7, 141.5, 133.5, 131.4, 130.5, 129.9, 129.5, 127.2, 126.4,
125.4, 124.9, 124.5, 124.2, 122.8, 29.2 (CH isopropyl), 24.4 (CH3 isopro-
pyl), 24.3 (CH3 isopropyl) ppm; IR (KBr): n˜ = 2962, 2869, 2231, 1708,
1667, 1600, 1513, 1472, 1406, 1340, 1258, 1207, 1151, 1020, 971, 909, 810,
737, 702, 576 cmÀ1; UV/Vis (methanol): lmax (e) = 504 (15200), 536 nm
3
3
(250 MHz, CD3OD, 300 K): d = 8.90 (d, J = 8.0 Hz, 2H), 8.17 (d, J =
3
3
8.0 Hz, 2H), 8.02 (s, 2H), 7.58 (d, J = 8.0 Hz, 4H), 7.16 (t, J = 7.5 Hz,
2H), 7.03 (d, 3J = 8.0 Hz, 4H), 6.94 (d, 3J = 8.0 Hz, 4H), 2.44 (m, 4H),
0.82 (m, 24H) ppm; 13C NMR (62.5 MHz, CD3OD, 300 K): d = 164.6 (q,
C=O), 164.2 (q, C=O), 157.8 (q), 155.5 (q), 147.1 (q), 142.9 (q), 134.4 (q),
131.6 (q), 131.5 (t), 130.7 (t), 130.5 (q), 129.7 (t), 129.6 (t), 127.3 (q),
126.7 (t), 126.1 (q), 125.5 (q), 125.1 (t), 123.6 (q), 119.5 (t), 30.4 (t, CH
isopropyl), 24.5 (t, CH3 isopropyl), 24.3 (t, CH3 isopropyl) ppm; IR
(KBr): n˜ = 3432, 2965, 2928, 2361, 2336, 1702, 1657, 1591, 1490, 1464,
1406, 1341, 1260, 1204, 1122, 1060, 1029, 1003, 911, 839, 812, 736, 690,
581 cmÀ1; UV/Vis (H2O): lmax (e) = 411 (7565), 523 (23196), 554 nm
(23718mÀ1 cmÀ1); fluorescence (H2O, excitation 560 nm): lmax = 594 nm;
MS (MALDI-TOF): m/z (%): 1057 (%) [M]+ (calcd 1055); elemental
analysis calcd (%) for C60H50N2O12S2: C 68.30, H 4.78, N 2.65; found: C
68.19, H 4.85, N 2.67.
(21100mÀ1 cmÀ1); fluorescence (methanol, excitation: 510 nm): lmax
575 nm; MS (FD 8 kV): m/z (%): 896.9 (100) [M]+ (calcd 897.0).
=
Compound 34b: 1,6(7)-Dibromoperylenetetracarboxylic acid diimide 32
(1.0 g, 1.15 mmol) was stirred under argon with phenol (0.94 g, 10 mmol)
in NMP (100 mL) at 1008C in a 250 mL round flask in the presence of
powdered anhydrous K2CO3 (690 mg, 5 mmol). The temperature was
maintained at 1008C overnight under argon. The reaction mixture was al-
lowed to cool to room temperature and was poured into aqueous hydro-
chloride acid (200 mL, 1m). The precipitated product was filtered under
suction, and was then purified by column chromatography to give a red
1
solid (700 mg, 68%). M.p. >3008C; H NMR (250 MHz, CD2Cl4, 300 K):
d = 9.56 (d, 3J = 8.0 Hz, 2H), 8.60 (d, 3J = 8.0 Hz, 2H), 8.27 (s, 2H),
7.43 (m, 6H), 7.25 (m, 10H), 2.61 (m, 4H), 1.06 (m, 24H) ppm; 13C
NMR (75 MHz, C2D2Cl4, 333 K): d = 163.5, 163.1, 156.6, 155.5, 155.2,
145.8, 134.0, 130.9, 129.9, 129.6, 129.2, 128.2, 126.0, 125.6, 124.5, 124.3,
124.2, 122.7, 119.9, 119.8, 29.4 (CH isopropyl), 24.3 CH3 isopropyl) ppm;
IR (KBr): n˜ = 2961, 2926, 2867, 2361, 2335, 1708, 1669, 1592, 1511, 1488,
Acknowledgement
1405, 1337, 1257, 1194, 1072, 970, 909, 865, 837, 812, 743, 685, 574 cmÀ1
UV/Vis (CHCl3): lmax (e) 406 (8868), 513 (35046), 545 nm
;
Financial support from the German Science Foundation (SFB 625,
Schwerpunktprogramm “Organische Feldeffekttransistoren”), the
German Ministry of Education and Research (“Nanocenter” Mainz), and
BASF AG is gratefully acknowledged.
=
(49387mÀ1 cmÀ1); fluorescence (CHCl3, excitation 510 nm): lmax
=
575 nm; MS (FD 8 kV): m/z (%): 895.4 (%) [M]+ (calcd 895.0); elemen-
tal analysis calcd (%) for C60H50N2O6: C 80.51, H 5.63, N 3.13%; found:
80.43, H 5.71, N 3.21.
Compound 35a: N,N’-Bis(2,6-diisopropylphenyl)-1,7-di(3-pyridoxy)pery-
lene-3,4:9,10-tetracarboxylic acid diimide 34a (1 g, 1.1 mmol) was treated
with methyl iodide (475 mg, 3.3 mmol) according to the procedure descri-
bed for the synthesis of 12a. Yield: 1.2 g (93%) as a red solid. M.p.
>3008C; 1H NMR (300 MHz, CH3OH-D4, 300 K): d = 9.42 (d, 3J =
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8.5 Hz, 2H), 9.05 (s, 2H), 8.65 (d, J = 8.5 Hz, 2H), 8.60 (d, J = 6.3 Hz,
2H), 8.53–8.50 (m, 4H), 8.00–7.94 (m, 2H), 7.38 (t, 3J = 7.9 Hz, 2H),
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3
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Received: March 25, 2004
Published online: September 21, 2004
5310
ꢀ 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
Chem. Eur. J. 2004, 10, 5297 – 5310