Fluorophore-Labeling Tetraphenylethene Dyes Ranging from Visible to Near-Infrared Region: AIE Behavior, Performance in Solid State, and Bioimaging in Living Cells

Article abstract of DOI:10.1021/acs.joc.9b01976

Functional molecules with aggregation-induced emission (AIE) have lately received the most attention due to their versatile functions in many fields. In this work, tetraphenylethene (TPE) as one of the most discussed AIE system was installed on different

Full text of DOI:10.1021/acs.joc.9b01976

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Article
Fluorophore-Labelling Tetraphenylethene Dyes Ranging
From Visible to Near-Infrared Region: AIE Behavior,
Performance in Solid State and Bioimaging in Living Cells
Weijie Chen, Chen Zhang, Xie Han, Sheng Hua Liu, Ying Tan, and Jun Yin
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.9b01976 • Publication Date (Web): 16 Sep 2019
Downloaded from pubs.acs.org on September 17, 2019
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Fluorophore-Labelling Tetraphenylethene Dyes
Ranging From Visible to Near-Infrared Region: AIE
Behavior, Performance in Solid State and Bioimaging
in Living Cells
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Weijie Chena, †, Chen Zhangb, †, Xie Hana, c, †*, Sheng Hua Liua, Ying Tanb* and Jun Yina, b*
a Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, Hubei International
Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, International
Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry,
Central China Normal University, Wuhan 430079, China.
b State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Biology, the
Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong, PR China, 518055.
c School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology,
Wuhan 430081, China.
† These authors contributed equally to this work.
*Corresponding
to:
yinj@mail.ccnu.edu.cn
；
tan.ying@sz.tsinghua.edu.cn
；
Hanxie@wust.edu.cn
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KEYWORDS: Tetraphenylethene, AIE, fluorophore, mechanoresponsive luminescence (MRL),
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bioimaging
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ABSTRACT: Functional molecules with aggregation-induced emission (AIE) have lately
received the most attention due to their versatile functions in many fields. In this work,
tetraphenylethene (TPE) as one of the most concerned AIE systems was installed on different
fluorophores including dansyl, naphthalimide, 4-nitro-1,2,3-benzoxadiazole (NBD),
borondipyrromethene (BODIPY), hemicyanine to afford a series of new fluorescent dyes, whose
spectra covered a fluorescence region of visible to near-infrared emission. Especially, these
tetraphenylethene-containing compounds all exhibited AIE behavior. In solid state, they presented
multicolor including blue, orange, red, crimson and NIR (near-infrared emission). It was worth
mentioning that the dansyl- and NBD- coating TPEs exhibited obvious mechanoresponsive
luminescence (MRL) phenomena. Moreover, these AIE-based TPEs displayed good bioimaging
performance in living cells. This work will be helpful for designing functional AIE dyes with
different fluorescence emission.
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Introduction
With the rapid development of visualization and imaging technology, functional fluorescent
dyes are of growing use in materials chemistry and biochemistry on the account of their marvelous
applications in organic semiconductors, fluorescent probes, chemosensors, bioimaging, diseases
diagnosis and therapy etc.1-16 To gain the fluorescent dyes with high performance, one of the
biggest challenges is that the dyes need to overcome the effect of fluorescence weakening or
quenching caused by molecular aggregation.17-22 As an opposite of aggregation caused quenching
(ACQ), the aggregation-induced emission (AIE)-active fluorescent dyes can weaken the influence
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of molecular aggregation. Over past several years, a large number of AIE molecules with various
function have been developed and applied in the fluorescence-related fields.23-28 For instance, their
high performance in solid state or thin film can be used to construct the stimuli-responsive
fluorescent sensors while their excellent behavior in aqueous can serve as the biomaterials to be
applied in bioimaging of living systems.29 Accordingly, exploring the multi-functional AIE-active
fluorescent dyes is vitally significant for promoting the development of imaging technology and
meeting the requirements of fluorescent dyes suitable for different imaging scenes.
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Tetraphenylethene (TPE), as the classic AIE-based molecular backbone, has been widely used
to construct the stimuli-responsive fluorescent sensors and bioimaging materials with AIE
performance by many groups.30 In our group, we employed the TPE backbone as a building block
to construct a series of fluorescent sensors and fluorescent probes in recent years.29, 31-32 In
consideration of the fact that these fluorescent TPEs were mainly in narrow region of spectra
emission and some TPEs were non-AIE active, we reported a series of AIE-based fluorescent dyes
ranging from visible to near-infrared region by fusing TPE moiety and different fluorophores
including dansyl, naphthalimide, 4-nitro-1,2,3-benzoxadiazole (NBD), borondipyrromethene
(BODIPY), hemicyanine in Scheme 1, and detailedly investigated their AIE behavior,
performance in solid state and bioimaging application.
O
N
O
NO2
N+
N
O
S
O
N
N+
B-
O
N
N
H
N
H
N
O
N
N
H
H
H
N
F
N
F
Cl
TPE-Blue
TPE-Orange
TPE-Red
TPE-Crimson
TPE-NIR
Scheme 1 The molecular structures of TPEs ranging from visible to near-infrared region.
Results and discussion
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Synthesis and structural details of TPEs. The TPEs were synthesized through the reaction of
TPE-based amine 1 with corresponding halogen-containing fluorophores, as outlined in Scheme
2. TPE-Blue was synthesized by the treatment of amine 1 and dansyl chloride 2 while TPE-
Orange was obtained by employing naphthalimide-based bromide 333 as a starting material to
carry out a coupling reaction of carbon-nitrogen bond formation with 1 in presence of Pd(OAc)2.
The nucleophilic substitution of amine 1 with chlorides 4 and 534, respectively, generated the
corresponding TPE-Red and TPE-Crimson. While TPE-NIR was obtained via the condensation
between 2,3,3-trimethyl-1-propyl-3H-indol-1-ium iodide 835 and TPE-based aldehyde 7 that was
prepared by a similar Pd-catalyzed coupling reaction of amine 1 with bromide 6. All new
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intermediates and targeting molecules were well characterized by H NMR, C NMR and mass
spectroscopies (see Figure S7-S20 in Supporting Information).
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N+
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CHO
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H
TPE-NIR
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OHC
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V
Br
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NH2
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TPE-Crimson
F
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Cl
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O2N
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III
II
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Cl
Br
4
3
O
N
O
NO2
N
N
O
N
N
H
H
N
O
TPE-Red
TPE-Orange
Scheme 2 The synthesis of the multi-color TPE derivatives. I) NEt3, DCM, R.T, 12 h, 65%. II) K2CO3, Pd(OAc)2,
toluene, 100 ℃, 12 h, 64%. III) NEt3, MeCN, reflux, 12 h, 51%. IV) NEt3, 1,4-dioxane, 80 ℃, 12 h, 45%. V)
Cs2CO3, Pd(dba)2, BINAP, toluene, 100 ℃, 16 h, 60%. VI) Pyridine, ethanol, 60 ℃, 12 h, 70%. (NEt3:
triethylamine, DCM: dichloromethane, R.T: room temperature, BINAP: (±)-2,2'-Bis(diphenylphosphino)-1,1'-
binaphthalene)
Further efforts paid for seeking more details of molecular structures by X-ray single crystal
diffraction. Fortunately, the single crystals of TPE-Blue and TPE-NIR suitable for
crystallographic analysis were obtained by slow diffusion of hexane into a CH2Cl2 solution of
TPE-Blue and TPE-NIR at room temperature, respectively. The corresponding crystallographic
data and thermal ellipsoid plots were summarized in Table S2, Figure S1 and S2 in Supporting
Information. From the crystal structure of TPE-Blue illustrated in Figure 1A, it was found that
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TPE component and dansyl-amide framework presented almost vertical configuration. And there
were multiple weak intermolecular interactions between molecules, including N-H···O (Figure
1B), C-H···N (Figure 1C), C-H···O (Figure 1D), and C-H···π (Figure 1E) interactions. Such
multi-interaction resulted that the fluorescent dye in crystalline phase presented highly ordered
stacking, as shown in Figure 1F. In which, the TPE components and naphthalene rings were
arranged in an alternating herringbone manner.
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Figure 1 The single crystal structure (A), N-H···O interaction (B), C-H···N interaction (C), C-H···O interaction
(D), C-H···π interaction (E) and the stacking view (F) of dye TPE-Blue.
According to the crystal structure of dye TPE-NIR in Figure 2A, TPE component showed
similar twisted configuration as well as dye TPE-Blue while the hemicyanine moiety exhibited a
planar structure. Analyzing the intermolecular interactions found that it mainly involved in three
weak interactions such as C-H···π interaction (Figure 2B) and N-H···N interaction (Figure 2C).
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In stacking view of TPE-NIR, the intermolecular hemicyanine components were arranged to a
face-to-face pattern, the distance of two aromatic centers is up to 3.925 Å (Figure 2D) owing to
the large space steric hindrance of TPE.
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Figure 2 The single crystal structure (A), C-H···π interaction (B), C-H···N interaction (C), centers distance (D)
and the stacking view (E) of dye TPE-NIR.
To gain insight into the electronic properties of TPEs, time-dependent density functional theory
(TD-DFT) calculations were carried out at the B3LYP/6-31G* level with the Gaussian 09 program
to explore their frontier molecular orbitals and electronic transitions upon photoexcitation.36 The
maximum absorption and corresponding molecular orbitals for these major electronic transitions
were shown in Figure 3. The optimized structure of TPE-Blue in Figure 3A exhibited a similar
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configuration with single crystal. The result of the absorption spectrum showed that TPE-Blue
involved in a main S0-S2 electronic transition (around 350 nm) with a large oscillator strength of
0.5166, corresponding to 57% contribution from the HOMO to LUMO+1 transition (Table S3 in
Supporting Information). More, its electron density of the highest occupied molecular orbital
(HOMO) was distributed in TPE moiety while the lowest unoccupied molecular orbital (LUMO)
was mainly localized on the dansyl-amide backbone. For dye TPE-Orange, it contained three
main absorption bands at around 482, 380 and 353 nm, respectively, as shown in Figure 3B. The
distribution of HOMO mainly focused on the morpholine ring while the LUMO was distributed in
naphthalimide fluorophore. Similar three absorption bands (at 560, 418 and 350 nm, respectively)
with large oscillator strengths were also observed in molecule of TPE-Red in Figure 3C.
Differently, its electron density of HOMO mainly distributed in TPE unit while LUMO was
located in NBD backbone. For BODIPY- and hemicyanine-cotaining TPE-Crimson and TPE-
NIR, they involved in multi-electronic transitions, as shown in in Figure 3D and Figure 3E.
Especially, the HOMO and LUMO electron density of all molecules had the charge transfer
characteristics, which implied that these dyes were probably fluorescent.37 Additionally,
investigation on the energy levels (such as 3.81, 2.99, 2.72, 2.45 and 1.63 eV, respectively) found
that they possessed a trend of decreasing band gaps, suggesting that their optical behavior had
gradual red-shift.
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Figure 3 Frontier molecular orbital profiles of (A) TPE-Blue, (B) TPE-Orange, (C)TPE-Red, (D)TPE-
Crimson and (E) TPE-NIR based on TDDFT (B3LYP/6-31G*) calculations.
AIE behavior. As known, TPE backbone has been widely applied in the construction of AIE-
based functional materials. In consideration of these molecules containing TPE unit, the
subsequent work focused on investigating their AIE behavior by UV-Vis absorption and
fluorescence spectra at room temperature. All measurements were carried out in a solution of
MeCN/H2O with different volume fractions of water (fw). Except for TPE-Blue (around at 220-
400 nm) with sulfonamide moiety, the UV-Vis absorption spectra of TPE-Orange, TPE-Red,
TPE-Crimson and TPE-NIR exhibited the main absorption band peaked at 450, 485, 497 and
537 nm (Figure S3 in Supporting Information), respectively. With increasing volume fractions of
water, no significant changes were observed (Figure S3 in Supporting Information).
Subsequently, their AIE behavior was clearly demonstrated in their fluorescence spectra. As
shown in Figure 4A, the emission peaks of TPE-Blue exhibited a complicated solvatochromic
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shift. In pure MeCN, TPE-Blue showed a yellow-green fluorescence around at 519 nm with the
absolute fluorescence quantum yield of 23%. Along with increasing the water fractions from 0 to
60%, its fluorescence red-shifted gradually to 538 nm emitting yellow emission and the absolute
fluorescence quantum yield displayed a slight reduction (Фf = 17%). The red shift was mainly due
to the intramolecular charge transfer (ICT) effect in response to the increasing solvent polarity of
the mixture solution. When the water fractions increased to over 60%, the emission intensity of
TPE-Blue increased gradually with the increase of water fractions. Simultaneously, the emission
peak blue-shifted to 497 nm and presented a green emission with enhanced fluorescence quantum
yields of 28% when the water fractions were up to 90% in Figure 4F, probably owing to the
formation of its aggregation, which restricted the intermolecular and intramolecular interactions
and led to higher energy emission.38-39 These observations were well consistent with the findings
of the previous work.
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（ A（
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（ D（
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TPE-Red
TPE-Orange
TPE-Crimson
TPE-NIR
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Figure 4 The fluorescence spectra of compounds (10 μM) TPE-Blue (A), TPE-Orange (B), TPE-Red (C),
TPE-Crimson (D) and TPE-NIR (E) in MeCN/H2O mixtures with different water fractions.
For the naphthalimide-containing fluorescent dye, TPE-Orange was non-fluorescent in pure
MeCN and its fluorescence intensity in mixture solution of MeCN-H2O showed few changes when
the water fractions were in range of 0-60% (Фf = 0.4% in MeCN), as presented in Figure 4B.
However, a dramatic enhancement of the fluorescence intensity at 606 nm was observed when the
water fractions changed from 70% to higher water fraction (90%, Фf = 1.5%) in Figure 4F, which
strongly suggested that TPE-Orange had typical AIE activity. In contrast, no traditional AIE
phenomenon was found when the NBD-based dye TPE-Red was carried out the same operation
(Figure 4C and Figure 4F), probably ascribing to the fact dye TPE-Red was difficult to form the
corresponding aggregation under the condition of MeCN-H2O solution. Similar to TPE-Orange,
the BODIPY-bearing dye TPE-Crimson revealed a typical AIE character. As described in Figure
4D, few changes of its fluorescence intensity in mixture solution of MeCN-H2O was detected on
the fw range of 0-50% (Фf = 0.3% in MeCN). Subsequently, a dramatic enhancement of the
fluorescence was observed at higher water fractions (60-90%) and the fluorescence intensity
peaked at 633 nm reached a maximum when the water fraction was 80% (Фf = 1.2%) in Figure
4F. In comparison to the above, the hemicyanine-moidified near-infrared dye TPE-NIR exhibited
a different AIE behavior. As could be found in Figure 4E, TPE-NIR showed an obvious
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fluorescence emission at 622 nm in pure organic solvent and the fluorescence intensity in MeCN-
H2O displayed slight enhancement when the water fractions were in range of 0-80% (Фf = 0.4% in
MeCN). However, its fluorescence red-shifted to 690 nm the fw was up to 90% (Фf = 0.9%) in
Figure 4F. These results strongly indicated that the introducing fluorophores was able to adjust
their fluorescence emission while the TPE unit might affect their AIE activity. For the reason, we
speculated that their AIE activity probably originated from the combination of ICT/TICT effect
and restricted intramolecular rotation (RIR) according to the above observations and the
solvatochromic properties (Figures S4 and S5 in Supporting Information). More, the further proof
was found when we measured their fluorescence spectra in mixture solutions of glycerol/methanol
with different viscosity (Figure S6 in Supporting Information). Especially for dye TPE-Red, its
emission intensity gradually increased with the enhancement of viscosity of solvent due to the RIR
process (Figure S6C in Supporting Information), which confirmed dye TPE-Red was AIE-
activated.
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Performance in solid state. To further confirm the AIE activity of these fluorescent dyes, we
investigated their fluorescence property in solid state. As presented in Figure 5A, the emission
peaks of TPE-Blue, TPE-Orange, TPE-Red, TPE-Crimson and TPE-NIR centered at 470, 611,
660, 665 and 722 nm, respectively, and ranged from visible to near-infrared region, as observed
from the images of their powder in Figure 5B. It was particularly worth mentioning that dye TPE-
Red revealed a bright red emission in solid state in comparison to its non-emissive behavior in
solution. The result strongly indicated that TPE-Red was also an AIE-active fluorescent dye.
Further proof was achieved by checking their absolute fluorescent quantum yields in solid state
which were 57%, 3.2%, 1.5%, 2.5% and 1.4% of TPE-Blue, TPE-Orange, TPE-Red, TPE-
Crimson and TPE-NIR, respectively. According to the data, it was found that they had higher
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fluorescent quantum yields in solid state than in solution, which completely verified that these
fluorophore-labelling TPEs had typical AIE behavior and their emission ranged from visible to
near-infrared emission.
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（ A （
TPE-Blue
TPE-Orange
TPE-Red
TPE-Crimson
TPE-NIR
1.2
1.0
0.8
0.6
0.4
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400 500 600 700 800 900
Wavelength / nm
( B )
TPE-Blue TPE-Orange TPE-Red TPE-Crimson TPE-NIR
Figure 5 The fluorescence spectra (A) and the emission images under 365 nm (B) of the TPEs in solid state.
For TPEs, numerous studies have confirmed that they possessed mechanically responsive
performance in powder.40-47 Accordingly, subsequent studies were conducted to explore their
mechanically induced fluorescence performance in solid state. The results showed that the dansyl-
based TPE-Blue and NBD-based TPE-Red exhibited mechanoresponsive properties in
comparison to others (Figure 6). The as-prepared pristine TPE-Blue exhibited a strong blue
emission at 470 nm. By mechanically grinding the powder of TPE-Blue using a pestle, an obvious
bathochromic emission at 492 nm was observed in Figure 6A. As a result of grinding, the absolute
fluorescence quantum yields increased largely from 57% to 78% with the changes of image color
from blue to bright green in Figure 6B. Interestingly, the bright blue emissions of the solid powder
was able to be fully recovered by fuming it with dichloromethane or heating it to 150 ℃ for 3 min
after the grinding process, suggesting that TPE-Blue had a reversible mechanochromic behavior.
To gain insight into the mechanism of mechanochromism process, we collected the powder X-ray
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diffractions (PXRD) spectra of the as-prepared, ground and the fumed/annealed TPE-Blue solids.
In Figure 6C, the spectrum of the as-prepared TPE-Blue had many sharp diffraction peaks,
implying the crystalline characteristic. In contrast, these sharp peaks almost disappeared upon
mechanically grinding, indicating that mechanical grinding changed the stacking of TPE-Blue
from the crystalline phase to the amorphous phases. Moreover, and the original crystalline state
can be regained by exposure to CH2Cl2 vapor or heating. These observations demonstrated that
the morphology transition between the crystalline and amorphous states was responsible for the
mechanochromism of TPE-Blue.
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In comparison to the bathochromic emission of TPE-Blue, TPE-Red exhibited a different
mechanoresponsive behavior. The as-prepared sample of TPE-Red showed a strong red emission
at 660 nm (In Figure 6D). Upon mechanically grinding, the bright red emission decreased
dramatically with the changes of fluorescent quantum yields from 1.7% to 0.6%. Similar solvent
fuming or thermal annealing can lead to a fully recovery of the red emission in Figure 6E.
Likewise, the process of crystalline-to-amorphous state transitions was able to be confirmed by
the PXRD in Figure 6F.
( B )
（ A（
1.0
（ C（
Unground
Ground
Annealed
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2θ
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（ D（
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Ground
Annealed
Fumed
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Ground
Annealed
Fumed
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DCM vapor
Ground
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Wavelength / nm
Figure 6 The MRL performance of TPE-Blue and TPE-Red. (A, D) The fluorescence spectra in solid state; (B,
E) Images under 365 nm UV irradiation (up) and daylight (down) of the as-prepared, ground and fumed samples;
(C, F) The XRD spectra.
Bioimaging in living cells. On account of the fact that these TPE-containing fluorescent dyes all
exhibited AIE activity and nearly covered the broad emission region from the visible channel to
NIR channel, we attempted to apply them in bioimaging of live cells. Accordingly, HeLa cells
were cultured in Dulbecco’s modified Eagle’s Medium (DMEM) supplemented with 10% fetal
bovine serum (FBS) and then incubated at 37 ℃ under a humidified atmosphere containing 5%
CO2. The cells were washed with ice-cold PBS three times and then incubated with fresh culture
medium. The solution (10 μM) of dyes TPE-Blue, TPE-Orange, TPE-Red, TPE-Crimson and
TPE-NIR, respectively, was prepared in phosphate buffered saline (PBS, pH = 7.4) containing
0.1% DMSO at 37 ℃. After incubating with HeLa cells for 0.5-4 h and then washing these cells
with PBS, the fluorescence images were collected using a confocal microscope. As could be
observed by viewing the confocal fluorescence microscope images shown in Figure 7, a series of
bright emission was able to be detected and presented multi-color character. These findings
strongly indicated that the AIE-active TPEs can serve as the tracking tools to be applied in
bioimaging.
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Figure 7 The confocal images of Hela cells in different emission channels with TPE-Blue (A), TPE-Orange
(B), TPE-Red (C), TPE-Crimson (D) and TPE-NIR (E) (The near-infrared fluorescence was modified
graphically to purple for visual clarity).
Conclusions
In summary, a series of new AIE systems, installing TPE on different fluorophores (dansyl,
naphthalimide, NBD, BODIPY, hemicyanine) were developed, with fluorescent spectra bands
covering the region from visible to near-infrared emission, showing multicolors including blue,
orange, red, crimson and NIR. Though the way of charge transfer, different coated blocks resulted
in the varied AIE behaviors. Surprisingly, the dansyl- and NBD-coating TPEs showed up obvious
MRL phenomena which were ascribed to the morphology transitions. Moreover, great staining
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performances in living cell were exhibited in these TPEs, implying a feasible method to construct
new functional AIE dyes with diverse optical properties. Our study provided a kind of design
strategy involving in ICT/TICT and RIR processes to construct the AIE functional materials with
multicolour through installing different fluorophores on TPE backbone.
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Experimental Section
Genenal. All reactions were carried out under a nitrogen atmosphere by using standard Schelenk
techniques. All starting materials were obtained commercially as analytical grade and the solvents
were used with dehydration and degassing purification. The compound 1 was a known structure,
and 3, 5 and 8 were synthesized according to the reported literatures.
1H and 13C NMR spectra were collected on an American Varian Mercury Plus 400/600
spectrometer (400/600 MHz) and used tetramethylsilane as the internal reference. Mass spectra
were recorded with an EI mass spectrometer. Elements analysis were measured by a Vario ElIII
Chnso analyzer. UV/Vis spectra were recorded by using a Hitachi U-3310 visible recording
spectrophotometer. Fluorescence spectra were recorded by using a Hitachi-F-4500 instrument.
Crystal structures were obtained on a Bruker APEX DUO charge-coupled device (CCD) system
through single crystal XRD experiments. Intensity data were collected on a Nonius Kappa CCD
diffractometer with Cu Kα radiation (λ = 1.54 Å) at room temperature. The structures were solved
by a combination of direct methods (SHELXS-97) and Fourier difference techniques and refined
by a full-matrix least-squares process (SHELXL-97). All non-hydrogen atoms were refined
anisotropically. Data on the structures reported here had been deposited with the Cambridge
Crystallographic Data Centre with deposition numbers CCDC 1937424 and 1937425. The
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hydrogen atoms were placed in ideal positions and refined as riding atoms. The quantum chemistry
calculation was performed on the Gaussian 03W (B3LYP/6-31G* basis set) software package.
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Synthesis of Compound 1 (1-(4-Aminophenyl)-1,2,2-triphenylethene). The Zn powders (14.8
g, 229 mmol) was added to a 250 mL two-necked flask, followed by the addition of dry THF (80
mL) under a nitrogen atmosphere. The reactants were cooled to 0-5 ℃, stirred for 0.5 h at room
temperature after the TiCl4 (21.0 g, 114.5 mmol) was added dropwise, then reflux for 2.5h. After
that, the reactants were cooled to 0-5 ℃ again, stirred for 10 min at room temperature after the
pyridine (4.5 g, 57.25 mmol) was added dropwise. Then benzophenone (5.0 g, 27.4 mmol) and 4-
aminobenzophenone (4.5 g, 22.9 mmol) in THF (50 mL) were then added dropwise, and reflux for
24 h. The mixture was poured into saturated sodium carbonate solutions. The residue was filtered
and washed with ethyl acetate. The combined organic layers were washed with water and brine,
dried over anhydrous Na2SO4, and evaporated under vacuum to afford 1, which was purified by
means of column chromatography, as a yellow solid (5.8 g, 74%).
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Synthesis of Compound 7 (4-((4-(1,2,2-triphenylvinyl)phenyl)amino)benzaldehyde). The 1
(100 mg, 0.29 mmol) and 6 (63.9 mg, 0.35 mmol), Cs2CO3 (6.6 mg, 1.06% mmol), Pd(dba)2 (2.0
mg, 0.35% mmol), BINAP (140 mg, 0.43 mmol) were dissolved in 10 mL dry toluene under a
nitrogen atmosphere. The reactants were stirred at 100 ℃ for 16 h. The mixture was then poured
into aqueous solution of ammonia and extracted with dichloromethane (3 x 20 mL). The combined
organic layers were washed with water and brine, dried over anhydrous Na2SO4, and evaporated
under vacuum to afford 7, which was purified by means of column chromatography, as a light-
yellow solid (78 mg, 60%). 1H NMR (600 MHz, CDCl3): δ (ppm) = 9.78 (s, 1H), 7.73 (d, J = 6
Hz, 2H), 7.05-6.92 (m, 21H), 6.12 (s, 1H). 13C{1H} NMR (150 MHz, DMSO-d6): δ (ppm) = 187.6,
146.7, 141.1, 140.9, 138.2, 137.5, 136.5, 135.6, 129.8, 129.4, 128.7, 125.8, 125.1, 125.0, 123.8,
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123.8, 117.2, 112.0, 106.0. EI-MS: m/z = 451.10 [M]+; calculated exact mass: 451.19. Anal. Calcd.
for C33H25NO: C, 87.77; H, 5.58; N, 3.10. Found: C, 87.62; H, 5.71; N, 3.22.
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Synthesis of TPE-Blue (5-(dimethylamino)-N-(4-(1,2,2-triphenylvinyl)phenyl)naphthalene-
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1-sulfonamide). The 1 (0.10 g，0.29 mmol) and 2 (0.11 g, 0.43 mmol) were dissolved in 30 mL
dry dichloromethane, followed by the addition of Et3N (0.2 mL) under a nitrogen atmosphere. The
reactants were stirred at room temperature for 12 h. The mixture was then evaporated and the
residue was dissolved in dichloromethane and extracted (3 x 20 mL). The combined organic layers
were washed with water and brine, dried over anhydrous Na2SO4, and evaporated under vacuum
to afford TPE-Blue, which was purified by means of column chromatography, as a white solid
(0.10 g, 65%). 1H NMR (400 MHz, CDCl3): δ (ppm) = 8.52(d, J = 8 Hz, 1H), 8.29 (d, J = 8 Hz,
1H), 8.08 (d, J = 8 Hz, 1H), 7.57 (t, J = 8 Hz, 1H), 7.43 (t, J = 10 Hz, 1H), 7.19 (d, J = 8 Hz, 1H),
7.06-6.89 (m, 15H), 6.76(d, J = 8 Hz, 2H), 6.63(d, J = 8.0 Hz, 2H), 6.53 (s, 1H), 2.89 (s,
6H).13C{1H} NMR (150 MHz, CDCl3): δ (ppm) = 152.0, 143.3, 141.0, 140.7, 139.8, 134.5, 133.9,
132.0, 131.2, 130.7, 130.4, 129.7, 128.6, 127.6, 126.4, 123.0, 120.8, 118.5, 115.2, 45.4. EI-MS:
m/z = 580.18 [M]+; calculated exact mass: 580.22. Anal. Calcd. for C38H32N2O2S: C, 78.59; H,
5.55; N, 4.82. Found: C, 78.70; H, 5.69; N, 4.73.
Synthesis of TPE-Orange (2-(2-morpholinoethyl)-6-((4-(1,2,2-triphenylvinyl)phenyl)amino)-
1H-benzo[de]isoquinoline-1,3(2H)-dione). The 1 (66 mg, 0.19 mmol), 3 (50 mg, 0.13 mmol),
K2CO3 (70 mg，0.51 mmol), Pd(OAc)2 (57 mg，0.26 mmol)were dissolved in 10 mL dry toluene
under a nitrogen atmosphere. The reactants were stirred at 100 ℃ for 12 h. The mixture was then
evaporated and the residue was dissolved in dichloromethane and extracted (3 x 20 mL). The
combined organic layers were washed with water and brine, dried over anhydrous Na2SO4, and
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evaporated under vacuum to afford TPE-Orange, which was purified by means of column
chromatography, as an orange solid (54 mg, 64%). 1H NMR (600 MHz, CDCl3): δ (ppm) = 8.61
(d, J = 6 Hz, 1H), 8.40 (d, J = 12 Hz, 1H), 8.25 (d, J = 6 Hz, 1H), 7.69 (t, J = 6 Hz, 1H), 7.28 (s,
1H), 7.21-6.88 (m, 18H), 6.75 (s, 1H), 4.33 (t, J = 7.0 Hz, 2H), 3.70 (s, 4H), 2.66 (d, J = 56.2 Hz,
6H). 13C{1H} NMR (100 MHz, CDCl3): δ (ppm) = 164.50, 163.86, 146.46, 143.8, 143.5, 143.5,
141.3, 140.4, 140.1, 138.0, 133.5, 132.8, 131.4, 131.4, 131.3, 129.9, 127.8, 127.7, 126.7, 126.6,
126.6, 126.5, 125.5, 123.2, 121.9, 121.3, 113.2, 109.2, 67.1, 56.3, 53.9, 37.1. EI-MS: m/z = 655.07
[M]+; calculated exact mass: 655.28. Anal. Calcd. for C44H37N3O3: C, 80.59; H, 5.69; N, 6.41.
Found: C, 80.41; H, 5.88; N, 6.56.
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Synthesis of TPE-Red (7-nitro-N-(4-(1,2,2-triphenylvinyl)phenyl)benzo[c][1,2,5]oxadiazol-
4-amine). The 1 (0.35 g, 1 mmol) and 4 (0.20 g, 1 mmol) and were dissolved in 30 mL dry MeCN,
followed by the addition of Et3N (0.1 mL) under a nitrogen atmosphere. The reactants were stirred
for reflux for 12 h. The mixture was then evaporated and the residue was dissolved in
dichloromethane and extracted (3 x 20 mL). The combined organic layers were washed with water
and brine, dried over anhydrous Na2SO4, and evaporated under vacuum to afford TPE-Red which
1
was purified by means of column chromatography, as a red solid (0.26 g, 51%). H NMR (400
MHz, CDCl3): δ (ppm) = 8.42 (d, J = 8 Hz, 1H), 7.65 (s, 1H), 7.12-7.02 (m, 19H), 6.66 (d, J = 8
Hz, 1H). 13C{1H} NMR (150 MHz, CDCl3): δ (ppm) = 144.7, 143.7, 143.2, 143.0, 143.0, 142.7,
142.0, 140.4, 139.4, 135.9, 134.5, 132.8, 131.2, 131.2, 131.1, 127.8, 127.6, 126.7, 126.6, 125.4,
122.1, 101.0. EI-MS: m/z = 510.13 [M]+; calculated exact mass: 510.17. Anal. Calcd. for
C32H22N4O3: C, 75.28; H, 4.34; N, 10.97. Found: C, 75.40; H, 4.27; N, 10.79.
Synthesis
of
TPE-Crimson
(7-chloro-5,5-difluoro-10-phenyl-N-(4-(1,2,2-
triphenylvinyl)phenyl)-5H-4l4,5l4-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborinin-3-amine). The
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1 (100 mg, 0.30 mmol) and 5 (100 mg, 0.30 mmol) and were dissolved in 30 mL dry 1,4-dioxane,
followed by the addition of Et3N (0.1 mL) under a nitrogen atmosphere. The reactants were stirred
at 80 ℃ for 12 h. The mixture was then evaporated and the residue was dissolved in
dichloromethane and extracted (3 x 20 mL). The combined organic layers were washed with water
and brine, dried over anhydrous Na2SO4, and evaporated under vacuum to afford TPE-Crimson,
which was purified by means of column chromatography, as a red solid (84 mg, 45%). 1H NMR
(600 MHz, CDCl3): δ (ppm) = 8.06 (s, 1H), 7.49-7.45 (m, 5H), 7.13-7.02 (m, 17H), 6.97 (d, J = 6
Hz, 2H), 6.89 (d, J = 6 Hz, 1H), 6.41 (d, J = 6 Hz, 1H), 6.37 (d, J = 6 Hz, 1H), 6.22 (d, J = 6 Hz,
1H). 13C NMR{1H} (150 MHz, CDCl3): δ (ppm) = 155.7, 140.7, 140.6, 140.5, 139.1, 139.0, 136.9,
132.7, 130.9, 130.8, 130.2, 123.0, 129.3, 128.6, 128.5, 127.6, 126.8, 125.6, 125.1, 125.0, 124.0,
124.0, 123.9, 119.0, 118.6, 110.7, 109.2. EI-MS: m/z = 646.94 [M]+; calculated exact mass:
647.21. Anal. Calcd. for C41H29BClF2N3: C, 76.00; H, 4.51; N, 6.49. Found: C, 76.19; H, 4.65; N,
6.33.
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Synthesis
of
TPE-NIR
((E)-3,3-dimethyl-1-propyl-2-(4-((4-(1,2,2-
triphenylvinyl)phenyl)amino)styryl)-3H-indol-1-ium). The entire process needed to be kept in
dark. The 7 (58 mg, 0.17 mmol) and 8 (80 mg, 0.17 mmol) and were dissolved in 20 mL dry
ethanol, followed by the addition of pyridine (0.1 mL) under a nitrogen atmosphere. The reactants
were stirred at 60 ℃ for 12 h. The mixture was then evaporated under vacuum to afford TPE-NIR,
which was purified by means of column chromatography, as a blue solid (94 mg, 70%). 1H NMR
(600 MHz, DMSO-d6): δ (ppm) = 9.43 (s, 1H), 8.35 (d, J = 18 Hz, 1H), 8.11 (d, J = 6 Hz, 2H),
7.82 (s, 2H), 7.57 (d, J = 24 Hz, 2H), 7.37 (d, J = 12 Hz, 1H), 7.18-6.96 (m, 20H), 4.54 (t, J = 6
Hz, 1H), 1.86-1.82 (m, 2H), 1.77 (s, 6H), 0.99 (t, J = 6 Hz, 3H). ESI-MS: m/z = 635.38 [M]+;
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calculated exact mass: 635.86. Anal. Calcd. for C47H43IN2: C, 74.01; H, 5.68; N, 3.67. Found: C,
74.15; H, 5.77; N, 3.49.
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ASSOCIATED CONTENT:
Supporting Information
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Optical characteristics of TPEs in the solid and liquid state, single-crystal X-ray diffraction data
and their ORTEP drawings of TPE-Blue (CCDC 1937424) and TPE-NIR (CCDC 1937425),
computational data of TPEs, UV−vis absorption spectra, absorption and emission
solvatochromism spectra, viscosity emission spectra of TPEs, 1H and 13C{1H} NMR, MS spectra
for TPEs.
Crystallographic information of TPE-Blue (CCDC 1937424)
Crystallographic information of TPE-NIR (CCDC 1937425)
AUTHOR INFORMATION:
Corresponding author
Jun Yin. Email: yinj@mail.ccnu.edu.cn
Ying Tan. Email: tan.ying@sz.tsinghua.edu.cn
Xie Han. Email: Hanxie@wust.edu.cn
Author contributions
J. Y. and Y. T. designed and supervised the research. X. H. designed, performed experiments and
analyzed data. C. Z. partially did experiments, along with a participation in analyzing data. W. C.
wrote the manuscript.
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There are no conflicts to declare.
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ACKNOWLEDGEMENTS
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The authors acknowledge financial support from National Natural Science Foundation of China
(21676113, 21402057, 21772054, 21472059); Distinguished Young Scholar of Hubei Province
(2018CFA079), Youth Chen-Guang Project of Wuhan (2016070204010098). Supported by the
111 Project B17019; Supported by the Ministry-Province Jointly Constructed Base for State Key
Lab-Shenzhen Key Laboratory of Chemical Biology (Shenzhen); Supported by the State Key
Laboratory of Materials-Oriented Chemical Engineering (KL17-10); Open Project Fund of Key
Laboratory of Natural Resources of Changbai Mountain & Functional Molecules (Yanbian
University, NRFM201701), Ministry of Education; Supported by the foundation of Key
Laboratory of Synthetic and Biological Colloids, Ministry of Education, Jiangnan University (No.
JDSJ2017-07); Supported by self-determined research funds of CCNU from the colleges' basic
research and operation of MOE (CCNU18TS012).
REFERENCES
(1) Sharma, A.; Arambula, J. F.; Koo, S.; Kumar, R.; Singh, H.; Sessler, J. L.; Kim, J. S.
Hypoxia-targeted drug delivery. Chem. Soc. Rev. 2019, 48, 771-813.
(2) Liu, Y.; Bhattarai, P.; Dai, Z.; Chen, X. Photothermal therapy and photoacoustic imaging
via nanotheranostics in fighting cancer. Chem. Soc. Rev. 2019, 48, 2053-2108.
(3) Chong, K. C.; Hu, F.; Liu, B. AIEgen bioconjugates for specific detection of disease-
related protein biomarkers. Mater. Chem. Front. 2019, 3, 12-24.
(4) Chen, Y.; Li, L; Chen, W.; Chen, H; Yin, J. Near-infrared small molecular fluorescent
dyes for photothermal therapy. Chin. Chem. Lett. 2019, 30, 1353-1360.
24
ACS Paragon Plus Environment

Page 25 of 30
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
(5) Gu, K.; Zhu, W.-H.; Peng, X. Enhancement strategies of targetability, response and
photostability for in vivo bioimaging. Sci. China Chem. 2019, 62, 189-198.
(6) Zhu, S.; Tian, R.; Antaris, A. L.; Chen, X.; Dai, H. Near‐Infrared‐II Molecular Dyes for
Cancer Imaging and Surgery. Adv. Mater. 2019, 31, 1900321.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(7) Chen, W.; Pan, Y.; Chen, J.; Ye, F.; Liu, S. H.; Yin, J. Stimuli-responsive organic chromic
materials with near-infrared emission. Chin. Chem. Lett. 2018, 29, 1429-1435.
(8) Gu, B.; Yong, K.-T.; Liu, B. Strategies to Overcome the Limitations of AIEgens in
Biomedical Applications. Small Methods 2018, 2, 1700392.
(9) Jung, H. S.; Verwilst, P.; Sharma, A.; Shin, J.; Sessler, J. L.; Kim, J. S. Organic molecule-
based photothermal agents: an expanding photothermal therapy universe. Chem. Soc. Rev.
2018, 47, 2280-2297.
(10) Wu, D.; Chen, L.; Lee, W.; Ko, G.; Yin, J.; Yoon, J. Recent progress in the development
of organic dye based near-infrared fluorescence probes for metal ions. Coord. Chem. Rev.
2018, 354, 74-97.
(11) Xu, Z.; Chen, J.; Hu, L.-L.; Tan, Y.; Liu S.-H.; Yin, J. Recent advances in formaldehyde-
responsive fluorescent probes. Chin. Chem. Lett. 2017, 28, 1935-1942.
(12) Chen, H.; Dong, B.; Tang, Y.; Lin, W. A Unique “Integration” Strategy for the Rational
Design of Optically Tunable Near-Infrared Fluorophores. Acc. Chem. Res. 2017, 50, 1410-
1422.
(13) Sun, W.; Guo, S.; Hu, C.; Fan, J.; Peng, X. Recent Development of Chemosensors Based
on Cyanine Platforms. Chem. Rev. 2016, 116, 7768-7817.
(14) Zhou, J.; Ma, H. Design principles of spectroscopic probes for biological applications.
Chem. Sci. 2016, 7, 6309-6315.
25
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 26 of 30
1
2
3
4
5
6
(15) Wu, X.; Zhu, W. Stability enhancement of fluorophores for lighting up practical
application in bioimaging. Chem. Soc. Rev. 2015, 44, 4179-4184.
7
8
9
(16) Yin, J.; Hu, Y.; Yoon, J. Fluorescent probes and bioimaging: alkali metals, alkaline earth
metals and pH. Chem. Soc. Rev. 2015, 44, 4619-4644.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(17) He, X.; Xiong, L.-H.; Zhao, Z.; Wang, Z.; Luo, L.; Lam, J. W. Y.; Kwok, R. T. K.; Tang,
B. Z. AIE-based theranostic systems for detection and killing of pathogens. Theranostics
2019, 9, 3223-3248.
(18) Shen, P.; Zhuang, Z.; Zhao. Z.; Tang, B. Z. AIEgens based on main group heterocycles.
J. Mater. Chem. C 2018, 6, 11835-11852.
(19) Feng, H.-T.; Yuan, Y.-X.; Xiong, J.-B.; Zheng, Y.-S.; Tang, B. Z. Macrocycles and cages
based on tetraphenylethylene with aggregation-induced emission effect. Chem. Soc. Rev.
2018, 47, 7452-7476.
(20) Gopikrishna, P.; Meher, N.; Iyer, P. K. Functional 1,8-Naphthalimide AIE/AIEEgens:
Recent Advances and Prospects. ACS Appl. Mater. Interfaces 2018, 10, 12081-12111.
(21) Yuan, Y.; Liu, B. Visualization of drug delivery processes using AIEgens. Chem. Sci.
2017, 8, 2537-2546.
(22) Mei, J.; Leung, N. L. C.; Kwok, R. T. K.; Lam, J. W. Y.; Tang, B. Z. Aggregation-
Induced Emission: Together We Shine, United We Soar! Chem. Rev. 2015, 115, 11718-
11940.
(23) Islam, Md. M.; Hu, Z.; Wang, Q.; Redshaw, C.; Feng, X. Pyrene-based aggregation-
induced emission luminogens and their applications. Mater. Chem. Front. 2019, 3, 762-781.
26
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Page 27 of 30
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
(24) Chen, Y.; Lam, J. W. Y.; Kwok, R. T. K.; Liu, B.; Tang, B. Z. Aggregation-induced
emission: fundamental understanding and future developments. Mater. Horiz. 2019, 6, 428-
433.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(25) Zhao, J.; Chi, Z.; Yang, Z.; Mao, Z.; Zhang, Y.; Ubba, E.; Chi, Z. Recent progress in the
mechanofluorochromism of distyrylanthracene derivatives with aggregation-induced
emission. Mater. Chem. Front. 2018, 2, 1595-1608.
(26) He, Z.; Ke, C; Tang, B. Z. Journey of Aggregation-Induced Emission Research. ACS
Omega 2018, 3, 3267-3277.
(27) Shi, J.; Li, Y.; Li, Q.; Li, Z. Enzyme-Responsive Bioprobes Based on the Mechanism of
Aggregation-Induced Emission. ACS Appl. Mater. Interfaces 2018, 10, 12278-12294.
(28) Zhu, C.; Kwok, R. T. K.; Lam, J. W. Y.; Tang, B. Z. Aggregation-Induced Emission: A
Trailblazing Journey to the Field of Biomedicine. ACS Appl. Bio Mater. 2018, 1, 1768-1786.
(29) Han, X.; Liu, Y.; Liu, G.; Luo, J.; Liu, S. H.; Zhao, W.; Yin, J. A Versatile
Naphthalimide–Sulfonamide‐Coated Tetraphenylethene: Aggregation‐Induced Emission
Behavior, Mechanochromism, and Tracking Glutathione in Living Cells. Chem. Asian J.
2019, 14, 890-895.
(30) La, D. D.; Bhosale, S. V.; Jones, L. A.; Bhosale, S. V. Tetraphenylethylene-Based
AIE-Active Probes for Sensing Applications. ACS Appl. Mater. Interfaces 2018, 10, 12189-
12216.
(31) Yang, Q.; Li, D.; Chi, W.; Guo, R.; Yan, B.; Lan, J.; Liu, X.; Yin, J. Regulation of
aggregation-induced emission behaviours and mechanofluorochromism of
tetraphenylethene through different oxidation states of sulphur moieties. J. Mater. Chem.
C 2019, 7, 8244-8249.
27
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 28 of 30
1
2
3
4
(32) Ma, X.; Hu, L.; Han, X.; Yin, J. Vinylpyridine- and vinylnitrobenzene-coating
5
6
7
8
tetraphenylethenes: Aggregation-induced emission (AIE) behavior and mechanochromic
property. Chin. Chem. Lett. 2018, 29, 1489-1492.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(33) Woo, J.; Kim, G.; Quintero, K.; Hanrahan, M. P.; Palencia, H.; Cao, H. Investigation
of desilylation in the recognition mechanism to fluoride by a 1,8-naphthalimide derivative.
Org. Biomol. Chem. 2014, 12, 8275-8279.
(34) Zhao, X.; Yu, C.; Feng, Z.; Yu, Y.; Wang, J.; Hao, E. Wei, Y.; Mu, X.; Jiao, L. Highly
Regioselective α-Chlorination of the BODIPY Chromophore with Copper(II) Chloride.
Org. Lett. 2015, 17, 4632-4635.
(35) Kang, N.-Y.; Park, S.-J.; Ang, X. W. E.; Samanta, A.; Driessen, W. H. P.;
Ntziachrisots, V.; Vasquez, K. O.; Peterson, J. D.; Yun, S.-W.; Chang, Y.-T. A macrophage
uptaking near-infrared chemical probe CDnir7 for in vivo imaging of inflammation. Chem.
Commun. 2014, 50, 6589-6591.
(36) Xu, Z.; Huang, X.; Han, X.; Wu, D.; Zhang, B.; Tan, Y.; Cao, M.; Liu, S. H.; Yin, J.;
Yoon, J. A Visible and Near-Infrared, Dual-Channel Fluorescence-On Probe for Selectively
Tracking Mitochondrial Glutathione. Chem 2018, 4, 1609-1628.
(37) Song, F.; Li, Z.; Li, J.; Wu, S.; Qiu, X.; Xi, Z.; Yi, L. Investigation of thiolysis of NBD
amines for the development of H2S probes and evaluating the stability of NBD dyes. Org.
Biomol. Chem. 2016, 14, 11117-11124.
(38) Xiong J.; Wang K.; Yao Z.; Zou B.; Xu J.; Bu X.-H. Multi-stimuli-responsive
fluorescence switching from a pyridine-functionalized tetraphenylethene AIEgen. ACS Appl.
Mater. Interfaces 2018, 10, 5819-5827.
28
ACS Paragon Plus Environment

Page 29 of 30
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
(39) Sturala J.; Etherington M. K.; Bismillah A. N.; Higginbotham H. F.; Trewby W.; Aguilar
J. A.; Bromley E. H. C.; Avestro A.-J.; Monkman A. P.; McGonigal P. R. Excited-State
Aromatic Interactions in the Aggregation-Induced Emission of Molecular Rotors. J. Am.
Chem. Soc. 2017, 139, 17882-17889.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(40) Xiong, J.; Wang, K.; Yao, Z.; Zou, B.; Xu, J.; Bu, X.-H. Multi-Stimuli-Responsive
Fluorescence Switching from a Pyridine-Functionalized Tetraphenylethene AIEgen. ACS
Appl. Mater. Interfaces 2018, 10, 5819-5827.
(41) Liu, F.; Tu, J.; Wang, X.; Wang, J.; Gong, Y.; Han, M.; Dang, X.; Liao, Q.; Peng, Q.; Li,
Q.; Li, Z. Opposite mechanoluminescence behavior of two isomers with different linkage
positions. Chem. Commun. 2018, 54, 5598-5601.
(42) Ma, Z.; Wang, Z.; Meng, X.; Ma, Z.; Xu, Z.; Ma, Y.; Jia, X. A Mechanochromic Single
Crystal: Turning Two Color Changes into a Tricolored Switch. Angew. Chem. Int. Ed. 2016,
55, 519-522.
(43) Qi, Q.; Qian, J.; Tan, X.; Zhang, J.; Wang, L.; Xu, B.; Zou, B; Tian, W. Remarkable
Turn‐On and Color‐Tuned Piezochromic Luminescence: Mechanically Switching
Intramolecular Charge Transfer in Molecular Crystals. Adv. Funct. Mater. 2015, 25, 4005-
4010.
(44) Gong, Y.; Tan, Y.; Liu, J.; Lu, P.; Feng, C.; Yuan, W. Z.; Lu, Y.; Sun, J. Z.; He, G.;
Zhang, Y. Twisted D-π-A solid emitters: efficient emission and high contrast
mechanochromism. Chem. Commun. 2013, 49, 4009-4011.
(45) Wang, J.; Mei, J.; Hu, R. Sun, J. Z.; Qin, A.; Tang, B. Z. Click Synthesis, Aggregation-
Induced Emission, E/Z Isomerization, Self-Organization, and Multiple Chromisms of Pure
29
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