Aggregation-induced emission and large two-photon absorption cross-sections of diketopyrrolopyrrole (DPP) derivatives

Article abstract of DOI:10.1071/CH11410

In this work, a new series of triphenylamine-based diketo-pyrrolo-pyrrole (DPP) compounds (DPP-I, DPP-II, DPP-III) have been designed and synthesized by a concise route. Their one- and two-photon absorption properties have been investigated. It was found that DPP-based compounds are very weakly fluorescent in THF solution, but their intensities are increased by almost 29, 9, and 24 times in water/THF (v/v90%) mixtures, respectively, in which they exhibit a strongly enhanced red fluorescence. The result indicates that the intramolecular vibration and rotation of these dyes is considerably restricted in nano-aggregates formed in water/THF mixtures, which leads to significant increases in fluorescence. The two-photon absorption (2PA) cross-sections measured by the open aperture Z-scan technique were determined to be 188, 275 and 447GM for DPP-I, DPP-II, and DPP-III, respectively; DPP-III with the symmetrical structure shows the highest value of 2PA cross-section. The excellent properties of aggregation-induced emission (AIE) and 2PA provide an attractive alternative for the biophotonic materials.

Full text of DOI:10.1071/CH11410

CSIRO PUBLISHING
Aust. J. Chem. 2012, 65, 387–394
Full Paper
http://dx.doi.org/10.1071/CH11410
Aggregation-Induced Emission and Large Two-Photon
Absorption Cross-Sections of Diketopyrrolopyrrole (DPP)
Derivatives
A
A
B
C
A
Bing Wang, Nannan He, Bo Li, Shuangying Jiang, Yi Qu,
A
A D
,
Sanyin Qu, and Jianli Hua
A
Key Laboratory for Advanced Materials, Institute of Fine Chemicals and Department
of Chemistry, East China University of Science and Technology, 130 Meilong Road,
Shanghai 200237, P. R. China.
B
Key Laboratory of Polar Materials and Devices, Ministry of Education, East China
Normal University, Shanghai 200241, P. R. China.
C
School of Environmental Science and Engineering, Tongji University,
Shanghai 200092, P. R. China.
D
Corresponding author. Email: jlhua@ecust.edu.cn
In this work, a new series of triphenylamine-based diketo-pyrrolo-pyrrole (DPP) compounds (DPP-I, DPP-II, DPP-III)
have been designed and synthesized by a concise route. Their one- and two-photon absorption properties have been
investigated. It was found that DPP-based compounds are very weakly fluorescent in THF solution, but their intensities are
increased by almost 29, 9, and 24 times in water/THF (v/v 90 %) mixtures, respectively, in which they exhibit a strongly
enhanced red fluorescence. The result indicates that the intramolecular vibration and rotation of these dyes is considerably
restricted in nano-aggregates formed in water/THF mixtures, which leads to significant increases in fluorescence. The
two-photon absorption (2PA) cross-sections measured by the open aperture Z-scan technique were determined to be 188,
275 and 447 GM for DPP-I, DPP-II, and DPP-III, respectively; DPP-III with the symmetrical structure shows the highest
value of 2PA cross-section. The excellent properties of aggregation-induced emission (AIE) and 2PA provide an attractive
alternative for the biophotonic materials.
Manuscript received: 22 October 2011.
Manuscript accepted: 19 February 2012.
Published online: 27 March 2012.
biophotonic applications.[4] It is necessary that 2PA dyes are
water soluble or dispersible and remain highly fluorescent in
aqueous media for biophotonic applications. Therefore a special
molecule for a 2PA material is needed, which not only has a large
two-photon activity, but also overcomes fluorescence quenching
in the aggregation. A novel phenomenon that overcomes fluores-
cence quenching inthe aggregation has recently beenobserved by
Tang and coworkers,[5] who also performed a series of tests to
externally and internally modulate the restriction of intramolecu-
lar rotation (RIR) process, which is a main cause for the
aggregation-induced emission (AIE) effect. Materials with AIE
propertues have been an active area of research for a wide variety
of promising applications, including 2PA, fluorescent switching
or sensing, electroluminescence devices and biological probes.[6]
Recently our group have designed and synthesized multi-
branched triarylamine end-capped triazines and cyano-substituted
diphenylamine styrylbenzene that exhibits large 2PA and special
AIE properties.[7] However, there are only few reports about
compounds with high 2PA and AIE to date, although the
structure–property relationship is of great value in terms of
gaining new insights into AIE mechanism and guiding further
research efforts in the development of new AIE luminogens.
Introduction
The promising applications of organic two-photon absorption
(2PA) materials in the two-photon dynamic therapy, three-
dimensional (3D) optical data storage, optical power limiting,
bioimaging, up-converted lasing[1] have attracted considerable
attention in the last decade. Since the concept of the two-photon
absorption (2PA) process was first proposed by M. Goppert-
Mayer in 1931, a variety of compounds with large 2PA
cross-section (s) including symmetrical donor-conjugated
bridge-donor (D-p-D), acceptor-conjugated bridge-acceptor
(A-p-A) and donor-conjugated bridge-acceptor-conjugated
bridge-donor (D-p-A-p-D), or asymmetrical donor-conjugated
bridge-acceptor (D-p-A) molecules have been synthesized and
their structure-property relationships investigated.[2] The con-
clusion was reached thatexpansion ofp-electron conjugation and
enhancement of intramolecular charge transfer will increase
the s value of a compound, which provided guidelines for
the development of materials with large 2PA cross-section.[3]
Recently, many compounds with large s value have been
designed and synthesized. However, most of them are hydropho-
bic and their fluorescence often quenches in the solid state due to
aggregation, which greatly limits their applications, especially
Journal compilation Ó CSIRO 2012
www.publish.csiro.au/journals/ajc

388
B. Wang et al.
O
C4H9
O
N
Br
N
N
O
C4H9
O
DPP-I
O
C4H9
O
N
CHO
S
N
N
O
C4H9
O
DPP-II
O
O
C4H9
O
N
N
N
N
O
C4H9
O
DPP-III
O
Scheme 1. Structures of DPP-based compounds.
1,4-Diketo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DPP) exhi-
bits brilliant red and strong fluorescence, and is therefore used
in industrial applications such as high performance pigments in
paints, plastics and inks.[8] Some special DPP-based derivatives
represent excellent materials for solution processed bulk-
heterojunction and dye-sensitized solar cells owing to their
exceptional photochemical, mechanical, and thermal stability.
Moreover there are some reports on the synthesis and 2PA
properties of DPP-based derivatives.[9] In addition, 2PA materi-
als with triarylamine as electron donor have aroused great
interest and become the focus of intensive research in the field
of 2PA materials owing to their good electron donating and
transporting capability,[10] as well as special propeller molecular
structure. Consequently, we functionalize electron-donating
triphenylamine groups with methoxy moieties to the electron-
withdrawing pyrrolo[3,4-c]pyrrole-1,4-dione via 1,4-phenylene
conjugation bridges to form new DPP-I-III dyes (Scheme 1).
It could be expected that the molecules with the methoxy
triarylamine propeller donor and DPP-based acceptor groups
should have excellent 2PA values as well as AIE properties.
DPP-based compounds were synthesized and characterized
One-Photon Absorption
Fig. 1 shows the normalized one-photon absorption of DPP-I-III
in tetrahydrofuran (THF) solution at dilute concentration. The
absorption maxima (lmax) and molar extinction coefficient (e)
of the dyes DPP-I, DPP-II and DPP-III appeared at 500
(2.7ꢀ 104 Mꢁ1 cmꢁ1), 520 (3.3ꢀ 104 Mꢁ1 cmꢁ1) and 515 nm
(4.5ꢀ 104 Mꢁ1 cmꢁ1), respectively. It is clear that the lmax of
DPP-II is red-shifted by 20 and 5 nm compared with those
of DPP-I and DPP-III, respectively, which is attributed to the
extended p-system and enhanced intramolecular charge transfer
(ICT) from triphenylamine to the thiophene aldehyde group.
AIE Properties
Since Tang and coworkers proposed the restriction of intramo-
lecular rotation (RIR) as the main cause for the AIE effect, the
precipitation method using THF as a water-miscible solvent
for dyes has been used to prepare stable water dispersions of
DPP-I-III nanoaggregates, where the intramolecular rotation
could be restricted. As expected, DPP-I, DPP-II and DPP-III
are soluble in common organic solvents such as THF and
dichloromethane but are insoluble in water. Fig. 2(1a) shows the
corresponding emission spectra of compound DPP-I in aqueous
THF with different water/THF ratios at 1 ꢀ 10ꢁ5 M. The emis-
sion from the THF solution of DPP-I was so weak that almost no
photoluminescence (PL) signal was recorded. However, the PL
signal was gradually enhanced with increasing water/THF
ratios, which revealed the increasing aggregate formation.
The solution for the 60: 40(v/v) water/THF mixtures displayed
a dramatic enhancement of red luminescence. When the
water/THF ratio reached 90%, the PL intensity boosted to
the maximum. The emission maxima had a little red shift with the
addition of water into the THF solution of DPP-I, which could
be ascribed to the change in the packing mode of the DPP-I-III
1
by H NMR and 13C NMR spectrometry, and HRMS (see the
Experimental Section).
Results and Discussion
Synthesis
The synthetic routes of the dyes are shown in Scheme 2. The
important intermediates (1and 2) and target compounds (DPP-I
and DPP-II) were obtained as reported earlier.[11] DPP-III was
synthesized by Suzuki coupling reaction of compound 1 with
4-(bis(4-methoxyphenyl)amino)phenylboronic acid. All these
DPP-based derivatives were unambiguously confirmed by
1H-NMR and 13C-NMR spectrometry and HRMS.

Diketopyrrolopyrrole Derivatives
389
OMe
C4H9
C4H9
N
MeO
N
O
O
Br
N
Br
O
N
N
O
N
C4H9
OMe
C4H9
1
DPP-III
MeO
Na2CO3 H2O
Pd(PPh3)4, THF
C4H9
N
MeO
OCH3
H3CO
O
Br
N
N
O
N
C4H9
DPP-I
B(OH)2
MeO
2
C4H9
N
MeO
O
CHO
HO
HO
S
CHO
B
S
N
O
N
THF, Na2CO3, Pd(PPh3)4
C4H9
MeO
DPP-II
Scheme 2. Synthetic routes to the DPP-based compounds.
1.2
induced owing to the intermolecular steric effect by aggregation.
Fig. 2(1d) shows the scanning electron microscope (SEM)
image of DPP-I, which reveals that a nanoscopic aggregate of
the dye was formed in the mixtures with high water contents,
giving further evidence that the increasing PL intensity was
caused by the increasing aggregation. Thus its AIE nature is duly
verified.
Although measuring the change in the fluorescence quantum
yield (FF) with the variation in the amount of added water can
give us a quantitative picture of the AIE process, such measure-
ments could be hampered by the Mie effect of the nanoaggregate
suspensions in the solvent mixtures, which makes the FF
determination inaccurate.[13] To make the comparison, we
estimated the integrals of the PL spectra shown in Fig. 2(1b).
As for DPP-I, there was no PL intensity in THF and was almost
unchanged in the solution for 0–50 % (v/v) water/THF mixture,
but the I/I0 ratio of the THF solution started to increase swiftly
upon addition of water to 60 % and reached the maximum when
water was added up to 90 %, as shown in Fig. 2(1b), which is
,30 times than that of the THF solution. It is clear that the
molecules started to aggregate at a water fraction of .60 % and
the size and population of the aggregates continue to increase as
the water fraction is increased by the trajectory of the I/I0 ratio
for DPP-I.
DPP-I
1.0
0.8
0.6
0.4
0.2
0
DPP-II
DPP-III
300
400
500
600
700
800
Wavelength [nm]
Fig. 1. Normalized one-photon absorption spectra of DPP-I-III in THF.
molecules in the aggregates and the increasing accumulation of
the molecules by aggregation leading to a better conjugation.
Restriction of the intramolecular rotations in the aggregates
blocks the channel of nonradiative decay, hence changing the dye
to a strong emitter.[12] The fluorescence behaviour of DPP-I
is well visualized through fluorescence images of solution
and nanoaggregate dispersions in Fig. 2(1b). Fig. 2(1c) shows
absorption of DPP-I in solution (THF) and in dispersion of the
nanoaggregate form (90 % water) at 1 ꢀ 10ꢁ5 M. The latter was
obviously broadened and red-shifted by nanoaggregation, indi-
cating that the planarization of the distorted conjugation is
Similar behaviour was observed for DPP-II (Fig. 2 (2a–2d)).
A dilute solution of DPP-II in THF gives very weak PL but in an
aqueous mixture with 90 % water, it emits strong red lumines-
cence with a 9-fold increase in the I/I0 ratio (Fig. 2 (2a)), which
means that nanoaggregations (Fig. 2(2d)) increased and that
DPP-II also is AIE active. However, the effects of DPP-III

390
B. Wang et al.
50
40
30
20
10
0
(1a)
(1b)
Water content
[vol %]
30
25
20
15
10
5
90
80
70
60
50
30
0
0
20
40
60
80
100
550
600
650
700
750
Wavelength [nm]
Water fraction [vol %]
(1d)
2.0
1.5
1.0
0.5
0
(1c)
0 %
90 %
400
500
600
700
Wavelength [nm]
16
(2a)
10
(2b)
Water content
[vol %]
8
6
4
2
0
12
8
90
80
70
60
50
30
0
4
0
600
650
700
750
0
20
40
60
80
100
Wavelength [nm]
Water fraction [vol %]
3.0
2.5
2.0
1.5
1.0
0.5
0
(2c)
(2d)
0 %
90 %
400
500
600
700
Wavelength [nm]
Fig. 2. (1a–3a) PL spectra of DPP-I-III in THF/water mixtures. (1b–3b) Plot of its PL peak intensity v. water content
of the solvent mixture. Inset: photos of DPP-I-III in the THF/water mixtures with 0 and 90 % water contents recorded
under illumination of a UV light. Dye concentration: 10ꢁ5 M; excitation wavelength: 350 nm. (1c–3c) Absorption of
DPP-I-III in solution (THF) and in dispersion of the nanoaggregate form (90 % water) at 1 ꢀ 10ꢁ5 M. (2d–3d) SEM
image of DPP-I-III nanoaggegates prepared in THF/H2O (1 : 9 v/v) at 1 ꢀ 10ꢁ5 M.
were a little different from DPP-I and DPP-II. The shallow-red
fluorescence was detected from the THF solution of DPP-III,
while a deep-red fluorescence emission was founded from the
90 % (v/v) water/THF mixture. Other behaviours are similar
with DPP-I. Therefore DPP-III exhibits aggregation-induced
emission enhancement (AIEE) activity. The solution for the
70 : 30 (v/v) water/THF mixture displays a dramatic enhance-
ment of luminescence. When more water is added to the dye, it
emits more intensely with a 24-fold increase in the I/I0 ratio
achieved at a water fraction of 90 % (v/v) (Fig. 2(3b)),

Diketopyrrolopyrrole Derivatives
391
100
75
50
25
0
(3a)
(3b)
Water content
25
20
15
10
5
[vol %]
90
80
70
60
50
30
0
0
550
600
650
700
750
0
20
40
60
80
100
Wavelength [nm]
Water fraction [vol %]
3.0
2.5
2.0
1.5
1.0
0.5
0
(3c)
(3d)
0 %
90 %
400
500
600
700
Wavelength [nm]
Fig. 2. (Continued)
suggesting that more and more nanoparticles have been pro-
duced (Fig. 2(3d)). The result indicates that the DPP-based
compounds have AIE or AIEE performance, in which DPP-I
exhibited a strongly enhanced red fluorescence. There are more
molecules for DPP-II aggregating just as discs pile up, owing to
p–p stacking interactions because it is more planar than DPP-I,
which leads to the weaker AIE property of DPP-II is compared
with the other two compounds. In addition, the PL intensity of
DPP-I in aggregation increased more than that of DPP-III
because the latter showed AIEE.
To further investigate the process of the aggregation of
DPP-I-III particles, the time-dependent evolution of the fluores-
cence spectroscopic investigations were carried out in the mixed
90 % H2O/THF solvents. The aggregation state was prepared by
slowly injecting concentrated THF solution of DPP-I-III into a
THF/water mixture of 90 % volume fraction of water when the
latter was being stirred. The concentration of the final solution
is 1 ꢀ 10ꢁ5 mol Lꢁ1. The solutions were clear and stable. With
increasing the aggregating time, the intensity of luminescence
for each compound increased, but it changed little (Fig. 3). It is
assumed that a portion of the dye molecules clustered together to
form tiny particles by mechanical shear stress. Then the portion
of the dye molecules remaining in the solvent mixture gradually
deposit onto the initially formed particles.[14] Thus, the degree of
arrangement between DPP-I-III molecules in the aggregates
can be increased by increasing the aggregation time. The the
emission enhancement was observed for every fluorophore. In
addition, the size of the nanoaggregates changed little over time,
suggesting that the nanoaggregates are stable.
shows the open-aperture Z-scan data and 2PA coefficient
obtained by data fitting. The 2PA cross-section s can be calcu-
lated by using the equation s ¼ hnb/N0, where N0 ¼ NAC is the
number density of the absorption centres, NA is the Avogadro
constant and C represents the solute molar concentration. The
values of 2PA cross-section (s) for DPP-I, DPP-II and DPP-III
are 188, 275 and 447 GM, respectively, at wavelength 800 nm.
Interestingly, the s value of DPP-III is higher than those of
DPP-I and DPP-II. The result could be explained by the addi-
tional degree of spatial delocalization of the mobile electrons for
DPP-III. The experimental result supports Marder’s proposed
design strategies.[16] Increasing the extent of symmetrical charge
transfer from the middle of the molecule to the ends, orvice versa,
results in a large increase of the 2PA cross-section. DPP-III is of
the symmetrical D-p-A-p-D-type molecular structure, while
DPP-I and DPP-II are D-p-A-p-A-type, indicating that DPP-III
may have a larger 2PA cross-section than DPP-I and DPP-II. As
we expected, it is consistent with the experimental data. Although
DPP-I and DPP-II have the same D-p-A-p-A-type molecular
structure, there are different interms of the conjugation length and
electron withdrawing groups. The 2PA cross-section of DPP-II is
larger than that of DPP-I, because the introduction of the thio-
phene group in the p-bridge extends the conjugated system by
importing hetero atoms. Moreover the aldehyde group in com-
pound DPP-II has a stronger electron-withdrawing ability com-
pared with the bromine atom in DPP-I. It is well known that a
higher strength of electron acceptor will cause a greater degree of
charge transfer in a donor-acceptor system, resulting in a higher
nonlinear optical response.[17]
Under the excitation of an 80-fs, 800 nm pulse, DPP-I, DPP-II
and DPP-III in a mixture of THF and water emit intense fluores-
cence with the peaks located at 670, 685 and 655 nm (Fig. 4(1b–
3b)), respectively. The good overlap between one- and two-photon
excitation fluorescence indicates that the emissions resulted from
Two-Photon Absorption Properties
2PA cross-sections of the DPP-I, DPP-II and DPP-III were
determined by femtosecond open aperture Z-scan technique
according to a previously described method.[15] Fig. 4(1a–3a)

392
B. Wang et al.
30
25
20
15
10
5
red light when excited with near-IR light (lex 800 nm) to absorb
two photons. Their values of 2PA cross-section (s) are 188, 275
and 447 GM, respectively, at wavelength 800 nm. DPP-III, with
its symmetrical structure, shows the highest value of 2PA cross-
section and the change in the end group can modify the optical
properties. This result provides a useful guideline for the design
of efficient 2PA materials with AIE properties.
DPP-I
0 min
3 min
6 min
9 min
12 min
15 min
Experimental Section
General
˚
Tetrahydrofuran (THF) was pre-dried over 4 A molecular sieves
0
600
650
700
750
and distilled under an argon atmosphere from sodium benzophe-
none ketyl immediately before use. All other solvents and che-
micals were purchased from Aldrich and used as received without
further purification. 3,6-Bis-(4-bromophenyl)-2,5-di-n-butyl-pyr-
rolo [3,4-c]-pyrrole-1,4-dione (compound 1), 4-(bis(4-methox-
yphenyl)-amino)phenyl boronic acid (compound 2), DPP-I and
DPP-II were synthesized according to the corresponding litera-
ture methods.[11] All other chemicals were purchased from
Aldrich and used as received without further purification.
1H and 13C NMR spectra were recorded on a Bruker AM-500
spectrometer using chloroform-d as solvent and tetramethylsilane
(d ¼ 0) as internal references. The UV-vis spectra were recorded
on a Varian Cary 500 spectrophotometer with 2-nm resolution at
room temperature. Fluorescence spectra were recorded on a
Varian Cary fluorescence spectrophotometer. 2PA cross-sections
of DPP-I, DPP-II and DPP-III were measured by the femtosec-
ond open-aperture Z-scan technique according to the previously
described method.[15] Samples for two-photon excited fluores-
cence (TPF) were excited by fs pulses with different intensities at
a wavelengthof800 nm. The repetitionrateof the laserpulseswas
250 kHz and the pulse duration was 80fs.
10
8
DPP-II
6
0 min
3 min
6 min
9 min
12 min
15 min
4
2
0
600
650
700
750
80
DPP-III
60
40
20
0
0 min
3 min
6 min
9 min
12 min
15 min
3-(40-(Bis(4-methoxyphenyl)amino)biphenyl-4-yl)-6-
(4-bromo-phenyl)-2,5-dibutylpyrrolo[3,4-c]pyrrole-1,4
(2H,5H)-dione (DPP-I)
Compound 1 (0.84 g, 1.50 mmol), Pd(PPh3)4 (10 mg, 0.01 mmol),
and Na2CO3 (1.06 g, 0.01 mol) in THF (30 mL) and H2O (5mL)
were heated to 458C under a nitrogen atmosphere for 30min.
A solution of compound 2 (0.63 g, 1.80mmol) in THF (10 mL)
was slowly added, and the mixture was refluxed for a further 12h.
After cooling to room temperature, the mixture was extracted
with CH2Cl2 (50 mL). The organic portion was combined and the
solvent removed by rotary evaporation. The residue was purified
by column chromatography on silica (CH2Cl2/petroleum ether¼
1:1, v/v) to give an orange solid (0.41 g). Yield 34.9%. dH
(CDCl3, 500 MHz) 7.89 (d, J ¼ 8.29, 2H), 7.72 (d, J 8.34, 4H),
7.66 (d, J 8.51, 2H), 7.48 (d, J 8.60, 2H), 7.12 (d, J 8.81, 4H), 6.99
(d, J 8.58, 2H), 6.86 (d, J 8.82, 4H), 3.82 (s, 6H), 3.75 (t, J 7.47,
7.63, 4H), 1.55, 1.65 (m, 4H), 1.20 , 1.35 (m, 4H), 0.85
(m, 6H). dC (125 MHz, CDCl3) 162.9, 162.56, 156.2, 149.0, 146.4,
143.7, 140.5, 132.2, 127.6, 126.5, 125.5, 120.1, 114.8, 110.2,
109.5, 55.5, 53.4, 41.9, 41.7, 31.6, 29.7, 20.0, 13.6. m/z (HR-ESI)
[M] calcd for C46H44BrN3O4: 781.2515, found: 781.2521.
600
650
700
750
Wavelength [nm]
Fig. 3. Dependence of the PL intensity of DPP-I-III to aggregating time in
THF-water mixture (1 : 9 v/v). DPP-I-III concentration: 1 ꢀ 10ꢁ5 mol/L.
Excitation wavelength: 350 nm.
the same excited state, regardless of the different mode of excita-
tion. It shall be noted that the two-photon excitation studies for
compounds DPP-I-III were performed at the one wavelength
(800 nm). We cannot measure the 2PA cross-section profile at
different wavelengths at present because of the limitation of our
laser apparatus. The cross-sections for the DPP-based compounds
would be better conducted at their relative 2-fold labs,max
.
Conclusions
In conclusion, we have developed a new class of aggregation-
induced emission (AIE)-active compounds, in which electron-
donating methoxy-triphenylamine was connected to the
diketopyrrolopyrrole (DPP) core to form three triarylamineDPP-
I-III derivatives. They are non-emissive when dissolved in an
organic solvent such as THF. Their nanoaggregates suspended in
aqueous media (e.g. 9 : 1 v/v H2O–THF), however, emit intense
5-(4-(4-(40-(Bis(4-methoxyphenyl)amino)biphenyl-4-yl)-
2,5-dibuty-l-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]
pyrrol-1-yl)phenyl)thiophene-2-carbaldehyde (DPP-II)
DPP-I (0.40 g, 0.51 mmol), Pd(PPh3)4 (10 mg, 0.01 mmol), and
Na2CO3 (1.06 g, 0.01 mol) in THF (10 mL) and H2O (5 mL)
were heated to 45 8C under a nitrogen atmosphere for 30 min.

Diketopyrrolopyrrole Derivatives
393
1.02
1.00
0.98
0.96
(1a)
150
120
90
(1b)
90 % H2O
60
0 % H2O
30
0
75
(2b)
1.02
1.00
0.98
0.96
0.94
(2a)
90 % H2O
60
45
30
15
0
0 % H2O
550
600
650
700
750
20
15
10
5
(3b)
1.02
0.98
0.94
0.90
0.86
(3a)
90 % H2O
0 % H2O
0
500
550
600
650
700
750
Ϫ1.0 Ϫ0.5
0
0.5
1.0
1.5
Wavelength [nm]
z [cm]
Fig. 4. (1a–3a) Open-Aperture Z-scan trace of DPP-I, DPP-II and DPP-III (scattered circle experimental data, straight line
theoretic fitted data). (1b–3b) Two-photon fluorescence emission spectra for DPP-I, DPP-II and DPP-III in solution (THF) and in
dispersion of the nanoaggregate form (90 % water) at 1 ꢀ 10ꢁ5 M, excited at 800 nm.
A solution of 5-formylthiophen-2-yl boronic acid (0.17 g,
1.10 mmol) in THF (5 mL) was slowly added, and the mixture
was refluxed for a further 12 h. After cooling to room temper-
ature, the mixture was extracted with CH2Cl2 (30 mL). The
organic portion was combined and the solvent removed by
rotary evaporation. The residue was purified by column chro-
matography on silica (CH2Cl2/ethyl acetate ¼ 70:1, v/v) to give
a red solid. Yield 46.6 %. dH (CDCl3, 500 MHz) 9.90 (s, 1H),
7.93 (m, 4H), 7.82 (d, J 8.29, 2H), 7.78 (d, J 3.84, 1H), 7.71
(d, J 8.25, 2H), 7.47 , 7.52 (m, 3H), 7.12 (d, J 8.81, 4H), 6.99
(d, J 8.54, 2H), 6.87 (d, J 8.84, 4H), 3.81 (m, 10H), 1.58 , 1.69
(m, 4H), 1.21 , 1.38 (m, 4H), 0.82 , 0.91 (m, 6H). dC
(125 MHz, CDCl3) 181.7, 161.9, 161.6, 155.2, 151.6, 148.0,
145.4, 142.3, 139.5, 136.3, 134.2, 128.5, 126.0, 125.7, 125.5,
124.8 124.0, 119.1, 113.8, 109.6, 108.6, 54.5, 52.4, 40.8, 30.6,
19.0, 12.6. m/z (HR-ESI) [M] calcd for C51H47N3O5S:
813.3236, found: 813.3254.
were heated to 458C under a nitrogen atmosphere for 30min.
A solution of compound 2 (1.58 g, 4.50 mmol) in THF (10 mL)
was slowly added, and the mixture was refluxed for a further 12h.
After cooling to room temperature, the mixture was extracted
with CH2Cl2 (50 mL). The organic portion was combined and the
solvent removed by rotary evaporation. The residue was purified
by column chromatography on silica (CH2Cl2/petroleum ether ¼
1:1, v/v) to give an orange solid (0.62 g). Yield 40.9 %.
dC (CDCl3, 500 MHz) 7.89 , 7.91 (d, J 4.0, 4H), 7.70, 7.72
(d, J 4.0, 4H), 7.47, 7.49 (d, J 4.0, 4H), 7.10, 7.13 (d, J 4.0,
8H), 6.98 , 7.01 (d, J 6.0, 4H), 6.85 , 6.88 (d, J 6.0, 8H), 3.82
(s, 16H), 1.25, 1.33 (m, 6H), 0.86, 0.89 (m, 8H). dC(125MHz,
CDCl3) 162.9, 156.2, 148.9, 148.0, 143.4, 140.5, 129.2, 126.9,
126.5, 120.2, 114.8, 109.7, 55.5, 53.4, 41.9, 31.6, 29.7, 20.0, 13.6.
m/z (HR-ESI) [M] calcd for C66H62N4O6: 1006.4669, found:
1006.4680.
Acknowledgements
3,6-Bis(40-(bis(4-methoxyphenyl)amino)biphenyl-4-yl)-2,5-
This work was supported by NSFC/China (2116110444 and 21172073),
National Basic Research 973 Program (2011CB808400), the Fundamental
Research Funds for the Central Universities (WJ0913001), and the Scientific
Committee of Shanghai (10520709700).
dibutylpyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP-III)
Compound 1 (0.84 g, 1.50mmol), Pd(PPh3)4 (10 mg, 0.01 mmol),
and Na2CO3 (1.06 g, 0.01 mol) in THF (30 mL) and H2O (5mL)

394
B. Wang et al.
References
[6] (a) Y. Hong, J. W. Y. Lam, B. Z. Tang, Chem. Commun. 2009, 4332.
doi:10.1039/B904665H
[1] (a) B. H. Cumpston, S. P. Ananthavel, S. Barlow, D. L. Dyer, J. E.
Ehrlich, L. L. Erskine, A. A. Heikal, S. M. Kuebler, I.-Y. S. Lee,
D. McCord-Maughon, J. Qin, H. Rockel, M. Rumi, X.-L. Wu, S. R.
Marder, J. W. Perry, Nature 1999, 398, 51. doi:10.1038/17989
(b) D. A. Parthenopoulos, P. M. Rentzepis, Science 1989, 245, 843.
doi:10.1126/SCIENCE.245.4920.843
(b) H. Tong, Y. Hong, Y. Dong, Y. Ren, M. Haeussler, J. W. Y.
Lam, K. S. Wong, B. Z. Tang, J. Phys. Chem. B 2007, 111, 2000.
doi:10.1021/JP067374K
(c) Z. Zhao, S. Chen, X. Shen, F. Mahtab, Y. Yu, P. Lu, J. W. Y.
Lam, H. S. Kwok, B. Z. Tang, Chem. Commun. 2010, 46, 686.
doi:10.1039/B915271G
(c) W. Denk, J. H. Strickler, W. W. Webb, Science 1990, 248, 73.
doi:10.1126/SCIENCE.2321027
(d) S. Kawata, H. B. Sun, T. Tanaka, K. Takada, Nature 2001, 412,
697. doi:10.1038/35089130
(e) H. M. Kim, B. H. Jeong, J. Y. Hyon, M. J. An, M. S. Seo, J. H. Hong,
K. J. Lee, C. H. Kim, T. Joo, S. C. Hong, B. R. Cho, J. Am. Chem. Soc.
2008, 130, 4246. doi:10.1021/JA711391F
(f) H. M. Kim, B. R. Cho, Acc. Chem. Res. 2009, 42, 863. doi:10.1021/
AR800185U
(d) X. B. Du, Z. Y. Wang, Chem. Commun. 2011, 47, 4276.
doi:10.1039/C1CC00066G
(e) B. Xu, J. T. He, Y. J. Dong, F. P. Chen, W. L. Yu, W. J. Tian,
Chem. Commun. 2011, 47, 6602. doi:10.1039/C1CC11706H
[7] (a) Y. H. Jiang, Y. C. Wang, J. L. Hua, J. Tang, B. Li, S. X. Qian,
H. Tian, Chem. Commun. 2010, 46, 4689. doi:10.1039/C0CC00803F
(b) B. Wang, Y. C. Wang, J. L. Hua, Y. H. Jiang, J. H. Huang, S. X.
Qian, H. Tian, Chem.–Eur. J. 2011, 17, 2647. doi:10.1002/CHEM.
201002821
(g) W. H. Zhou, S. M. Kuebler, K. L. Braun, T. Y. Yu, J. K. Cammack,
C. K. Ober, J. W. Perry, S. R. Marder, Science 2002, 296, 1106.
doi:10.1126/SCIENCE.296.5570.1106
[8] Y. Zhu, A. R. Rabindranath, T. Beyerlein, B. Tieke, Macromolecules
2007, 40, 6981. doi:10.1021/MA0710941
[9] E. Q. Guo, P. H. Ren, Y. L. Zhang, H. C. Zhang, W. J. Yang, Chem.
Commun. 2009, 5859. doi:10.1039/B911808J
[10] (a) G. S. He, L. S. Tan, Q. Zheng, P. N. Prasad, Chem. Rev. 2008, 108,
[2] (a) B. Strehmel, V. Strehmel, Advances in Photochemistry 2006,
Volume 29, p. 111 (Eds D. C. Neckers, W. S. Jenks, T. Wolff)
(John Wiley: Hoboken, NJ). doi:10.1002/047003758X.CH3
(b) M. Rumi, S. Barlow, J. Wang, J. W. Perry, S. R. Marder, Adv.
Polym. Sci. 2008, 213, 1.
1245. doi:10.1021/CR050054X
(b) M. Pawlicki, H. A. Collins, R. G. Denning, H. L. Anderson, Angew.
Chem. Int. Edit. 2009, 48, 3244. doi:10.1002/ANIE.200805257
[11] S. Y. Qu, W. J. Wu, J. L. Hua, H. Tian, J. Phys. Chem. C 2010, 114,
1343. doi:10.1021/JP909786K
[12] (a) Y. Q. Dong, J. W. Y. Lam, A. Qin, Z. Li, J. Sun, H. H. Y. Sung,
I. D. Williams, B. Z. Tang, Chem. Commun. 2007, 239.
(b) Z. Li, Y. Q. Dong, Y. H. Tang, M. Haubler, H. Tong, Y. Dong, J. W. Y.
Lam, K. S. Wong, P. Gao, I. D. Williams, H. S. Kwok, B. Z. Tang,
J. Phys. Chem. B 2005, 109, 10061. doi:10.1021/JP0503462
(c) Y. Q. Dong, J. W. Y. Lam, Z. Li, A. Qin, H. Tong, Y. Dong,
X. Feng, B. Z. Tang, J. Inorg. Organomet. P. 2005, 15, 287. doi:10.
1007/S10904-005-5546-0
(c) G. S. He, L. S. Tan, Q. Zheng, P. N. Prasad, Chem. Rev. 2008, 108,
1245. doi:10.1021/CR050054X
(d) F. Terenziani, C. Katan, E. Badaeva, S. Tretiak, M. Blanchard-
Desce, Adv. Mater 2008, 20, 4641. doi:10.1002/ADMA.200800402
(e) H. M. Kim, B. R. Cho, Chem. Commun. 2009, 153.
(f) M. Pawlicki, H. A. Collins, R. G. Denning, H. L. Anderson, Angew.
Chem. Int. Edit. 2009, 48, 3244. doi:10.1002/ANIE.200805257
(g) Z. J. Liu, P. Shao, Z. L. Huang, B. Liu, T. Chen, J. G. Qin, Chem.
Commun. 2008, 2260. doi:10.1039/B718147G
(h) Y. Qian, K. Meng, C. G. Lu, B. Lin, W. Huang, Y. P. Cui, Dyes
Pigments 2009, 80, 174. doi:10.1016/J.DYEPIG.2008.07.005
(i) C. C. Lin, M. Velusamy, H. H. Chou, J. T. Lin, P. T. Chou,
Tetrahedron 2010, 66, 8629. doi:10.1016/J.TET.2010.09.041
(j) Y. H. Jiang, Y. C. Wang, B. Wang, J. B. Yang, N. N. He, S. X. Qian,
J. L. Hua, Chem. Asian J. 2011, 6, 157. doi:10.1002/ASIA.201000536
(k) Y. H. Jiang, Y. C. Wang, J. B. Yang, J. L. Hua, B. Wang, S. X. Qian,
H. Tian, J. Polym. Sci. A Polym. Chem. 2011, 49, 1830. doi:10.1002/
POLA.24608
(d) Y. Q. Dong, J. W. Y. Lam, A. Qin, J. X. Sun, J. Z. Liu, Z. Li,
J. Z. Sun, H. Y. Sung, D. Williams, H. S. Kwok, B. Z. Tang, Chem.
Commun. 2007, 3255. doi:10.1039/B704794K
[13] Y. Liu, X. T. Tao, F. Wang, J. Shi, J. Sun, W. Yu, Y. Ren, D. Zou, M. H.
Jiang, J. Phys. Chem. C 2007, 111, 6544. doi:10.1021/JP070288F
[14] X. Feng, B. Tong, J. B. Shen, J. B. Shi, T. Y. Han, L. Chen, J. G. Zhi,
P. Lu, Y. G. Ma, Y. P. Dong, J. Phys. Chem. B 2010, 114, 16731.
doi:10.1021/JP108254G
[15] Y. H. Jiang, Y. C. Wang, J. L. Hua, S. Y. Qu, S. Q. Qian, H. Tian,
J. Polym. Sci. Pol. Chem. 2009, 47, 4400. doi:10.1002/POLA.23493
[16] R. C. Bong, H. S. Kyung, H. L. Sang, S. S. Young, K. L. Yun, J. J.
Seung, H. C. Jun, L. Hochan, C. Minhaeng, J. Am. Chem. Soc. 2001,
123, 10039. doi:10.1021/JA010770Q
[3] G. S. He, J. Swiatkiewicz, Y. Jiang, P. N. Prasad, B. A. Reinhardt, L. S.
Tan, R. Kannan, J. Phys. Chem. A 2000, 104, 4805. doi:10.1021/
JP000370þ
[4] S. Kim, Q. D. Zheng, G. S. He, D. J. Bharali, H. E. Pudavar, A. Baev,
P. N. Prasad, Adv. Funct. Mater. 2006, 16, 2317. doi:10.1002/ADFM.
200500928
[17] A. Bhaskar, G. Ramakrishna, Z. Lu, R. Twieg, J. M. Hales, D. J.
Hagan, E. V. Stryland, III, T Goodson, J. Am. Chem. Soc. 2006, 128,
11840. doi:10.1021/JA060630M
[5] J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok,
X. Zhan, Y. Liu, D. Zhu, B. Z. Tang, Chem. Commun. 2001, 34, 1740.
doi:10.1039/B105159H