Tetraphenylethene-based star shaped porphyrins: Synthesis, self-assembly, and optical and photophysical study

Article abstract of DOI:10.1021/jo502760e

Supramolecular self-assembly and self-organization are simple and convenient ways to design and create controlled assemblies with organic molecules, and they have provoked great interest due to their potential applications in various fields, such as elect

Full text of DOI:10.1021/jo502760e

Subscriber access provided by SUNY DOWNSTATE
Article
Tetrapheneylethene- based Star Shaped Porphyrins:
Synthesis, Self-assembly, Optical and Photophysical Study
Anushri Rananaware, Rajesh S Bhosale, Kei Ohkubo, Hemlata Patil, Lathe A Jones,
Sam L Jackson, Shunichi Fukuzumi, Sidhanath V Bhosale, and Sheshanath V. Bhosale
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/jo502760e • Publication Date (Web): 30 Mar 2015
Downloaded from http://pubs.acs.org on April 3, 2015
Just Accepted
“Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted
online prior to technical editing, formatting for publication and author proofing. The American Chemical
Society provides “Just Accepted” as a free service to the research community to expedite the
dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts
appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been
fully peer reviewed, but should not be considered the official version of record. They are accessible to all
readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered
to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published
in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just
Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor
changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers
and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors
or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
The Journal of Organic Chemistry is published by the American Chemical Society.
1155 Sixteenth Street N.W., Washington, DC 20036
Published by American Chemical Society. Copyright © American Chemical Society.
However, no copyright claim is made to original U.S. Government works, or works
produced by employees of any Commonwealth realm Crown government in the course
of their duties.

Page 1 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
Tetraphenylethene ꢀbased Star Shaped Porphyrins: Synthesis, Selfꢀ
assembly, Optical and Photophysical Study
7
8
9
Anushri Rananaware,† Rajesh S. Bhosale,‡,$ Kei Ohkubo,§ Hemlata Patil,† Lathe
A. Jones,†,┴ Sam L. Jackson,† Shunichi Fukuzumi,§ Sidhanath V. Bhosale,‡
Sheshanath V. Bhosale*,†
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
†School of Applied Sciences, RMIT University, GPO Box 2476, Melbourne, VICꢀ
3001, Australia
‡Polymers and Functional Material Division, CSIRꢀIndian Institute of Chemical
Technology, Hyderabadꢀ500 007, Telangana, India
§Department of Material and Life Science Graduate School of Engineering Osaka
University GSE Common East 12F, 2ꢀ1 Yamadaꢀoka, Suita, Osaka, 565ꢀ0871, Japan
$RMITꢀIICT Research Centre, CSIRꢀIndian Institute of Chemical Technology,
Hyderabadꢀ500 007, Telangana, India
┴Centre for Advanced Materials and Industrial Chemistry (CAMIC), RMIT
University, GPO Box 2476, Melbourne Victoria 3001 Australia
* Corresponding Author, Email: sheshanath.bhosale@rmit.edu.au
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 2 of 28
1
2
3
4
Table of Contents/Abstract Graphic
5
6
7
8
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
ACS Paragon Plus Environment

Page 3 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
ABSTRACT
7
8
9
Supramolecular selfꢀassembly and selfꢀorganisation are simple and convenient ways
to design and create controlled assemblies with organic molecules, and they have
provoked great interest due to their potential applications in various fields such as
electronics, photonics, and lightꢀenergy conversion. Herein, we describe the synthesis
of two πꢀconjugated porphyrin molecules bearing tetraphenylethene moities with high
fluorescence quantum yield. Photophysical and electrochemical studies were
conducted to understand the physical and redox properties of these new materials,
respectively. Furthermore, these derivatives used to investigate selfꢀassembly via the
solvophobic effect. The selfꢀassembled aggregation was performed in nonꢀpolar and
polar organic solvents which forms nanospheres and ringꢀlike nanostructures,
respectively. The solution based aggregation was studied by means of UVꢀvis
absorption, emission, XRD and DLS analyses. Selfꢀassembled ringꢀshape structures
were visualised by SEM and TEM imaging. This ringꢀshape morphology of nanosized
macromolecules might be good candidates for the creation of artificial lightꢀ
harvesting nanodevices.
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
INTRODUCTION
Selfꢀassembly and selfꢀorganisation of optically active and planar aromatic molecules
have generated much interest due to possible applications in versatile fields such as
electronics, photonics, lightꢀenergy conversion, and catalysis.1,2 Among aromatic
molecules, porphyrin derivatives continue to attract much attention due to their unique
πꢀconjugation and aggregation properties.3,4 Porphyrinic derivatives have thus been
used for the construction of molecular assemblies having wellꢀdefined shapes and
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 4 of 28
1
2
3
4
5
6
7
8
9
dimensions such as spheres, tubes, rods, nanosheets, nanorings, microrings and
nanowires.5ꢀ10 Interesting morphologies that have been described include the selfꢀ
assembly of structures from nanospheres to nanofibers, formation of nanosheets, and
ring shaped architectures.11ꢀ16 Amongst all the above nanostructures, the ringꢀshaped
assemblies of porphyrins are among those known to occur in nature, in the bacterial
lightharvesting complex LH2.17 In the LH2 complex, porphyrin molecules are
arranged as in the ring of a turbine and are responsible for the absorption of light and
storage & transportation of light energy to the reaction centre, where it is converted
into chemical energy. Photoinduced electron transfer (PET) and excited energy
transfer (EET) reactions are essential processes for mimicking natural
photosynthesis,18,19 and these processes are very important for various applications
such as optoelectronic devices,20 biological systems,21 solar cells and medicinal
applications (photodynamic therapy).22ꢀ24 In general, intramolecular PET and EET
systems involve two chromophores, with porphyrins having received significant
attention due to its similarity in structure to chlorophylls.25,26
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
On the other hand, mechanochromic luminescent materials have recently attracted
attention due to their potential applicability in fields such as mechanoꢀsensors,
security papers and optoelectronic devices.27,28 In 2001, the Tang group reported for
the first time that luminescence of silole molecules is stronger in the aggregate state
than in the solution state,29,30 leading to the so–called “aggregationꢀinduced emission”
(AIE)31 and “aggregationꢀinduced emission enhancement” (AIEE)32 phenomena. In
recent years, tetraphenylethene (TPE) has become one of the bestꢀknown AIE
fluorogens and its derivatives have found great potential in various applications such
as chemosensors, bioꢀprobes, solidꢀstate emitters, as well as realꢀtime cell apoptosis
imaging.33,34 Interestingly, TPE has also been used for supramolecular building
ACS Paragon Plus Environment

Page 5 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
blocks,35ꢀ37 and fluorescence ‘‘turn on’’ chemosensors for selective detection of Ag+
and Hg2+ ions.34 In our previous work,38 tetrapyridylꢀbased TPE was used for
reversible sensing of H+. Thus, continuing our efforts in the field, we are interested to
develop materials with conjoint use of porphyrin and TPE moieities and to study their
selfꢀassembly, optical and photophysical properties.
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
RESULTS AND DISCUSSION
Synthesis. Herein, we report the synthesis of a new TPEꢀbased porphyrin, its
aggregation behaviour via solvophobic control, and photophysical and
electrochemical properties for the first time. The synthesis of TPEꢀporphyrins 1 and 2
are shown in Scheme 1. The synthesis started from the reaction of 5 with 6 in the
presence of nꢀbutyl lithium (nꢀBuLi, 2.5 M in hexane), followed by dehydration in the
presence of pꢀtoluene sulphonic acid (pꢀTSA), to afford bromoꢀTPE 4 in 83% yield.
Suzuki coupling between 4 and (5ꢀformylthiophenꢀ2ꢀyl)boronic acid (7) gave
compound TPEꢀaldehyde 3 in 62% yield. TPEꢀporphyrin (1) was prepared by
condensation of 3 with pyrrole in propionic acid at reflux temperature for 1 h, and
gave 7% yield. Metallisation of 1 with Zn(OAc)2 in CHCl3/MeOH gave zincꢀTPEꢀpor
2 in 48% yield.
Scheme 1. Synthesis of TPEꢀporphyrin derivatives 1 and 2.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 6 of 28
1
2
3
4
5
6
7
8
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
UVꢀvis absorption and fluorescence spectroscopy. The TPEꢀpor 1 and its zinc
analogue 2 (ca. 1.2×10ꢀ4 M), are very soluble in chloroform and presents a spectrum
that is expected based on the porphyrinic core (Figure 1). The UVꢀvis absorption of 1
gives typical salient features including an intense Soret band at 447 nm (ε = 3×105 Mꢀ
1 cmꢀ1), along with four weaker Qꢀbands at 527, 578, 582 and 655 nm and the band at
342 nm is a typical absorption band of TPE moities19. Interestingly, all the bands in
the absorption spectrum are largely red shifted (see SI Fig. S1) compared to
5,10,15,20ꢀtetra(thiophenꢀ2ꢀyl)porphyrin (TThP).39 The zinc analogue of TPEꢀpor 2
(ca. 0.5×10ꢀ4 M) gives a sharp Soret band at 447 nm (ε = 5×105 Mꢀ1 cmꢀ1) along with
two typical Qꢀbands at 568 and 613 nm, and the band corresponding to TPE appeared
at 337 nm. A range of concentrations were measured to ensure that a linear
relationship was maintained between absorbance and emission intensities for both of
ACS Paragon Plus Environment

Page 7 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
the derivatives (1 and 2). These results show that the UV−vis absorption of the TPEꢀ
por derivatives can be readily tuned by the effect of TPE at the porphyrin core. The
UV−vis absorption of the porphyrin derivatives is significantly red shifted, which
may be attributed to the elongated πꢀconjugation between the porphyrin and the four
TPE moieties compared to zincꢀTThP.39
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
Figure 1. (a) UV−vis absorption and (b) emission spectra (λex = 440 nm) of
compound 1 and 2 in CHCl3, respectively.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 8 of 28
1
2
3
4
5
6
7
8
9
The fluorescence spectra of 1 and 2 upon excitation at 440 nm in CHCl3 solution are
shown in Figure 1b. At this excitation wavelength, the porphyrin cores are selectively
excited. As can be seen in Fig. 1b, an intense emission band at about 700 nm was
observed for 1 with a quantum yield of 15%, which is larger than that of freeꢀbase
TThP (Fig. S2, ~8%). This can be rationalized by the elogation πꢀconjugation
between TPE and porphyrin moities, which makes the molecule much more rigid and
reduces the vibrational decay of the excited states efficiently. Similar fluorescence of
the zinc analogue 2 (Fig. 1b, blue line), excitation at 440 nm results in emission from
porphyrin at 650 nm with Φf = 0.12, which is larger than that of ZnTPP (Φf =
0.010).39
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
Solution based Selfꢀassembly. We investigated the solvophobic effect on the
aggregation behaviour of TPEꢀPor 1. Figure 2 shows the absorption spectra of 1 in a
mixture of CHCl3/MeOH and CHCl3/cyclohexane. In the CHCl3/cyclohexane
mixture, it can be clearly seen that aggregation affects the spectrum with a significant
blueꢀshift (5 nm) of the absorption band (iii) along with peak broadening. However, in
CHCl3/MeOH, the UVꢀvis absorption band (ii) is redꢀshifted (4 nm) with peak
broadening. Fluorescence spectroscopy provides evidence for aggregation of 1,
depending on the solvent used. Compound 1 shows emission at 700 nm in
chloroform, which is blueꢀshifted (4 nm) in CHCl3/cyclohexane (1:1, v/v). However,
in CHCl3/MeOH emission is decreased with peak broadening as shown in Figure 2b.
This suggests that the mode of aggregation varies depending on the solvent used.
Nevertheless, when more than 50% of MeOH or cyclohexane is used, the compound
precipitates. The absorption and emission spectroscopy suggest the formation of faceꢀ
toꢀface πꢀstacks of TPEꢀpor chromophores similar to the ones reported in the case of
Jꢀ and Hꢀaggregates in other porphyrinic derivatives.3ꢀ16
ACS Paragon Plus Environment

Page 9 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
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
Figure 2. (a) UV−vis absorption and (b) fluorescence spectra (λex = 378 nm) of
compound 1 (1.0×10ꢀ4 M) in CHCl3, CHCl3/MeOH (1:1, v/v) and CHCl3/cyclohexane
(1:1, v/v), respectively. (c) Timeꢀdependent (from top to bottom) changes of the
hydrodynamic diameter (DH) distributions obtained by eight DLS measurements of
solutions in CHCl3ꢀMeOH (1:1, v/v) of 1 (1×10ꢀ4 M). Data was started 10 min after
the preparation of sample solutions and was taken at 5 min intervals.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 10 of 28
1
2
3
4
5
6
7
8
9
Dynamic Light Scattering (DLS) Analysis of Nanostructures. To support the
formation of nanostructures of 1 in CHCl3/MeOH (1:1, v/v), the solution was assessed
by dynamic light scattering (DLS) analysis. The extended assemblies with
hydrodynamic diameters (DH) of 20–100 nm were detected, besides larger assemblies
of around 300–700 nm with the lapse of time (from topꢀtoꢀbottom Figure 2c).
Interestingly, the average DH of assemblies showed a timeꢀdependent increase that
exceeded 0.5 ꢀm after 30 minutes (3rd curve from bottom in Figure 2c). This is an
indication of the presence of nonꢀequilibrated, extended supramolecular assemblies
that are expected to be spherical in shape. The cobmined results of UVꢀvis, emission
and DLS analysis suggest that there are different modes of aggregation depending on
solvent used, which led us to further investigate the aggregation of 1 by means of
scanning electron microscopy (SEM).
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
Scanning Electron Microscopy (SEM). Samples of 1 in 50% v/v cyclohexane or
MeOH in CHCl3 were spin coated onto silicon (111) wafers and analysed by SEM.
Compound 1 ([1]=1×10ꢀ4 M) aggregated into wellꢀformed ringꢀlike nanostructures
that extended down to nanometer sizes by changing the solvophobicity i.e. in 50% v/v
CHCl3/MeOH mixes (Figure 3a). Interestingly, three types of the ringꢀlike
nanostructures were identified. The size of the ringꢀlike nanostructures are 0.25 ꢀm,
0.50 ꢀm and 0.75 ꢀm, indicating a doubling then trebling of the thinnest of the
porphyrin nanostructures. This is probably due to the fact that TPEꢀporphyrin 1
undergoes the nucleation process originated by 2ꢀD coordination interactions with
adjacent porphyrins which further comes together to form 3ꢀD structures driven by the
crystal lattice packing based on πꢀπ stacking of 2ꢀD assembled layered structures
during the selfꢀassembly process. In case of highly concentrated solutions of 1 (1×10ꢀ2
ACS Paragon Plus Environment

Page 11 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
M), we observed the merging of a number of ringꢀlike nanostructures into amorphous
particles of porphyrins (see SI Fig. S3ꢀS5), while 1×10ꢀ6 M solution gave relatively
small ringꢀlike nanostructures which corresponded to the length of approximately one
porphyrin molecule (see SI Fig. S6).
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
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 12 of 28
1
2
3
4
5
Figure 3. Scanning electron micrograph of 1 ([1] = 1x10ꢀ4 M) in: (a) 50% v/v
CHCl3/MeOH and (b) 50% v/v CHCl3/cyclohexane solvent mixtures, respectively.
6
7
8
The bar represents 1 ꢀm.
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
In cyclohexane/CHCl3 (50% v/v) mixture, compound 1 ([1]=1×10ꢀ4 M) selfꢀ
assembled into defined spherical aggregates that extended to nanometres in size i.e.
150–300 nm (Figure 3b and S7). Compound 1 produced sheets at lower
concentrations (10ꢀ6 M), however, at higher concentration (10ꢀ2 M), honeyꢀcomb like
morphologies were observed along with particles (see SI; Fig. S8 and S9). It is
important to mention that increasing the amount of MeOH or cyclohexane to beyond
50% causes the compound to precipitate out of the solution and no microꢀ or nanoꢀ
structures were observed, which is an indication of the delicate balance of
solvophobicity with nonꢀcovalent interactions that lead to nanostructure formation.
No supramolecular structure is seen by this technique in pure chloroform.
An important factor to consider from a design point of view is that compound 2, in
which the porphyrin core is converted to the zinc analogue, failed to produce ring like
nanostructures, and only particular aggregates were observed at any proportion of
MeOH or cyclohexane in CHCl3 (See SI Fig. S10).
Transmission electron microscopy (TEM)
The ringꢀshaped nature of the supramolecule assembly of 1 was further confirmed by
transmission electron microscopy (TEM) imaging. Figure 4 shows the TEM image of
a droplete of CHCl3/MeOH (1:1, v/v) of 1 (10ꢀ4 M) was placed on carbonꢀcoated
copper grid. Wellꢀdefined circular ringꢀshaped morphology is clearly seen with size
varies in between 200ꢀ700 nm and the width of the rim at 10ꢀ25 nm, respectively
(Figure 4a). To understand more about the effect of the solvents with selfꢀassembly
ACS Paragon Plus Environment

Page 13 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
behaviour, we changed the solvent and performed selfꢀassembly in CH3CN/MeOH
and CH3CN/cyclohexane. It can be clearly seen that 1 (10ꢀ4 M) in CH3CN/MeOH
(1:1, v/v) selfꢀassembled into bundles of ringꢀshape morphology with size variying
from 60ꢀ150 nm (Fig. 4b). However, compound 1 in CH3CN/cyclohexane (1:1, v/v)
assembled into particular aggregates as shown in Figure 4c.
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
Figure 4. TEM images on a carbonꢀcoated copper grid of 1 (10ꢀ4 M) from an
equimolar mixture of (a) CHCl3/MeOH, (b) CH3CN/MeOH and (c)
CH3CN/cyclohexane, respectively. (d) XRD profiles of the aggregates of compound
1 formed in CHCl3/MeOH (1:1, v/v).
Xꢀray powder diffraction (XRD) analysis. The nanostructure of the 1 (10ꢀ4 M) was
fabricated by injecting a small volume of solution of 1 (CHCl3/MeOH, 1:1, v/v) into
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 14 of 28
1
2
3
4
5
6
7
8
9
1.5 mm diameter Lindéman capillaries and was characterised. The internal structure
of selfꢀassembled aggregates was investigated by XRD analysis (Figures 4d). In the
low angle range, the XRD diagram of the nanoscale hollow spheres formed from
compound 1 in CHCl3/MeOH shows typically three refraction peaks at 2θ = 1.83o,
2.41o, and 6.11o, corresponding to 5.10 nm, 3.81 nm and 1.87 nm, respectively, which
are ascribed to the refractions from the (010), (100), and (001) planes.40
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
The ringꢀsizes observed in TEM, SEM and DLS based assembly suggest a flattening
upon being transferred from solution to the silicon surface. Although the selfꢀ
assembly is predominantly driven by Jꢀ and Hꢀ type of aggregation via π−πꢀstacking
interactions between the large aromatic cores of 141, solvophobicity plays an
important role in the formation of each stack in ringꢀlike nanostructures as shown
schematically in Fig. 5. The formed assemblies are assumed to be the ringꢀshaped
nanostructures observed by SEM, TEM and the similar sizes of the rings observed by
DLS analysis.
ACS Paragon Plus Environment

Page 15 of 28
The Journal of Organic Chemistry
1
2
3
4
Figure 5. Graphical representation of selfꢀassembled TPEꢀporphyrin in polar
5
6
(CHCl3/MeOH) and nonꢀpolar (CHCl3/cyclohexane) mixing solvent, respectively.
7
8
9
Electrochemistry. Cyclic voltammetry was used to investigate the redox behaviour
of 1 and 2. The free base TPEꢀporphyrin 1 shows two reversible reduction couples
corresponding to formation of an anion radical and dianion respectively, and an
irreversible first oxidation couple for formation of a cation radical on the central
porphyrinic πꢀring system, which is preceded by an adsorption peak (Figure 6 and see
supporting information for a data table and full details of electrochemical studies).
The voltammogram for 2 shows that the introduction of Zn(II) affects the reversibility
of the first radical anion under these conditions, with the first cathodic peak becoming
irreversible followed by a quasireverisble couple. Comparing the first oxidation peak
of 1 with the first oxidation peak of 2 (ignoring adsorption peaks) we see that there is
not a significant shift due to the introduction of Zn(II), although the first reduction
process of 2 does become easier, indicating stabilisation of the LUMO orbital. If we
use the onset potentials to estimate the electrochemical bandgap (Eg), the free ligand
(1) is slightly larger, (1.74 V) compared to 2 (1.54 V).42,43 The first oxidation peak of
ZnTThP has been shown to have a E1/2 value of 0.43 V, anodic of ZnTPP (0.34 V),39
whereas 2 has a value of 0.39 V, indicating that the TPE groups make the porphyrinc
core easier to oxidise compared to ZnTThP, due to the increased conjugation in the
porphyrin ring.
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
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 16 of 28
1
2
3
4
5
6
7
8
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
Figure 6. Cyclic voltammograms of 1 (black, top) and 2 (blue, bottom) in
DCM/TBAPF6 at a scan rate of 50 mV/sConditions: Glassy Carbon working
electrodes, Pt counter electrode, Ag pseudoreference electrode and Fc/Fc+ internal
standard.
Photophysical Study. Timeꢀresolved transient absorption spectra of 1 were measured
by femtosecond laser flash photolysis to study the dynamics of excited states. A
transient absorption spectra observed after the femtosecond laser pulse excitation at
λ
= 393 nm in a cyclohexane/CH3CN (9:1, v/v) mixꢀsolution of 1 are shown in Figure
7a. The transient absorption bands at 490, 550, 630 and 730 nm are those of
characteristic singlet excited state of 1.44 The intersystem crossing of the singlet
excited state of 1 to the triplet was monitored at 730 nm (Figure 7b). The lifetime of
the singlet excited state of 1 was determined as 1.4 ns which is shorter than the
ACS Paragon Plus Environment

Page 17 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
excited state lifetime of the singlet excited states of a free base tetraphenylporphyrin
(H2TPP;
τ τ
= 10 ns)45 and zinc tetrathienyl porphyrin ( = 1.4 ns).39 Thus, the
7
8
9
intersystem crossing going to the triplet excited state is enhanced by the heavy atom
effect of four sulphur nuclei in the thiophene spaces.39 No electron transfer was
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
observed between the porphyrin and tetraphenylethene entities.
When the
photodynamics of 1 were observed in the mixꢀsolvent of MeOH/ CH3CN (9:1 v/v), the
singlet excited state was significantly quenched with the lifetime of 1.4 ps (Figure
7b). This suggests that singletꢀsinglet annihilation to be the S0 state occurs between πꢀ
stacked porphyrin molecules in a polar medium as show in Figure 4.46 In the case of a
zinc complex 2, a similar behaviour was observed as shown in Figure 7c and 7d.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 18 of 28
1
2
3
4
5
6
7
8
9
Figure 7. Transient absorption spectra of a) 1 in cyclohexane/PhCN (9:1 v/v), b) 1 in
MeOH/PhCN (9:1 v/v), c) 2 in cyclohexane/PhCN (9:1 v/v), and d) 2 in MeOH/PhCN
(9:1 v/v) taken after femtosecond laser excitation at 393 nm. Insets: Time profiles of
absorbance at 730 nm. The gray lines were drawn by singleꢀexponential curve fitting.
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
Xꢀray Crystal Analysis. Xꢀray crystals of TPEꢀaldehyde 3 suitable for analysis were
grown by vapour diffusion of hexane into a CHCl3 solution (Figure 8).47 The structure
exhibits 2D packing with extensive πꢀπ interactions through the tetraphenylethene and
thiophene. The layers have an alternating orientation of the molecules. Each phenyl
ring of the tetraphenylethene has faceꢀtoꢀedge interactions with two other rings.
Alternatively each thiophene exhibits faceꢀtoꢀface stacking with two other thiophenes
in other layers (See Supplementary Information Figure S10ꢀS13). However, after
several trial crystals of 1 and 2 were obtained by slow evaporation of CHCl3ꢀ
cyclohexane mixture at room teperature. Unfortunately, the size of crystals were too
small to be analysed by Xꢀray diffraction.
Figure 9. Ellipsoid representation of the asymmetric unit cell of intermediate
compound 3 (hydrogen atoms omitted for clarity). Ellipsoids calculated at 50%
probability.
ACS Paragon Plus Environment

Page 19 of 28
The Journal of Organic Chemistry
1
2
3
4
5
CONCLUSION
6
7
8
9
The results described herein are remarkable, as we demonstrate the possibility of
constructing defined supramolecular architectures of ringꢀshaped morphology at
micromolar concentrations of TPEꢀcapped πꢀconjugated porphyrin molecules. The
formation of rings were determined by SEM imaging and photophysical studies
support the πꢀstacking of TPEꢀporphyrins. Therefore, the present assembly is novel as
πꢀelectronic segments are spatially arranged in closed circular ringꢀshape structures,
which is reminiscent of the lightꢀharvesting systems of purple photosynthetic bacteria
in which the chlorophyll pigments are crucial for efficient excitation energy
migration.48 The electrochemical studies show that changes in the linker and the
electronegativity of the substituents would be able to be tuned to control the band gap
of porphyrinic building block in supramolecular structures, which is especially
important in applications involving electron transfer. We are also elaborating the
current design strategy for the creation of various π−conjugated donorꢀacceptor
functional architectures of defined size and shape.
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
EXPERIMENTAL SECTION
General Methods & Materials. All reagents were used as such without any further
purification. All the solvents were received from commercial sources and purified by
standard methods. Pyrrole, propionic acid, pꢀtoluenesulfonic acid (PTSA) chloroform,
methanol dichloromethane and hexane were purchased and used without purification,
unless otherwise specified. 1H NMR, 13CꢀNMR spectra were recorded using
chloroformꢀd as solvent and tetramethylsilane as an internal standard. The solvents for
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 20 of 28
1
2
3
4
5
6
7
8
9
spectroscopic studies were of spectroscopic grade and used as received. Mass
spectrometric data were obtained by MALDIꢀTOF spectrometer technique.
Sample preparation. Stock solutions (c = 10ꢀ2 M) of 1 or 2 were made in CHCl3. A
0.1 mL aliquot of the stock solution of each one was transferred separately to four
different volumetric flasks of (i) CHCl3 (100%), (ii) CHCl3/MeOH (1:1, v/v), (iii)
CHCl3/MeOH (1:1, v/v) and made up to 2 mL volume with respective solvents. The
solutions were allowed to equilibrate for 30 min prior to the UVꢀvis, flurescence
spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron
Microscopy (TEM) measurements.
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
Fluorescence Spectroscopy. Fluorescence emission spectra were performed in a
quartz cell with a 1 cm path length with 440 nm excitation wavelength.
Scanning Electron Microscopy (SEM). SEM measurements were performed on a
FEI Nova NanoSEM operating at high vacuum and SEM and images were collected.
Freshly prepared 0.5 ꢀL of TPEꢀporphyrin (1 and 2) samples were dropꢀcasting the
solutions on glass coverslip and solvent evaporation.
Transmission Electron Microscopy (TEM). A drop of solution of 1 (10ꢀ4 M) from
respective solutions were cast onto a carbon copper grid and the sample was allowed
to stand for 20 sec and removed of excess solution by blotting. The samples were then
negatively stained with 5% (w/v) uranyl acetate for 5 min and allowed to dry and
images were measured on a JEOLꢀ100CX II electron microscope operated at 80 kV.
Transient Absorption Spectroscopy. Femtosecond transient absorption
spectroscopy experiments were conducted using an ultrafast source: IntegraꢀC, an
optical parametric amplifier: TOPAS and a commercially available optical detection
system: Helios provided by Ultrafast Systems LLC. The source for the pump and
probe pulses were derived from the fundamental output of IntegraꢀC (λ = 786 nm, 2
ACS Paragon Plus Environment

Page 21 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
mJ/pulse and fwhm = 130 fs) at a repetition rate of 1 kHz. 75% of the fundamental
output of the laser was introduced into a second harmonic generation (SHG) unit:
7
8
Apollo (Ultrafast Systems) for excitation light generation at
λ = 393 nm, while the
9
rest of the output was used for white light generation. The laser pulse was focused on
a sapphire plate of 3 mm thickness and then white light continuum covering the
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
visible region from
λ = 410 nm to 800 nm was generated via selfꢀphase modulation. A
variable neutral density filter, an optical aperture, and a pair of polarizer were inserted
in the path in order to generate stable white light continuum. Prior to generating the
probe continuum, the laser pulse was fed to a delay line that provides an experimental
time window of 3.2 ns with a maximum step resolution of 7 fs. In our experiments, a
wavelength at
λ = 393 nm of SHG output was irradiated at the sample cell with a spot
size of 1 mm diameter where it was merged with the white probe pulse in a close
angle (< 10°). The probe beam after passing through the 2 mm sample cell was
focused on a fiber optic cable that was connected to a CMOS spectrograph for
recording the timeꢀresolved spectra (λ = 410 ꢀ 800 nm). Typically, 1500 excitation
pulses were averaged for 3 seconds to obtain the transient spectrum at a set delay
time. Kinetic traces at appropriate wavelengths were assembled from the timeꢀ
resolved spectral data. All measurements were conducted at room temperature, 295 K.
Synthesis of 1ꢀ(4ꢀbromophenyl)ꢀ1, 2, 2ꢀtriphenylethene (4). This compound was
prepared following known literature procedure.49 Typically, nꢀButylꢀlithium (2.5 M in
hexane, 19.0 mL, 47.59 mmol) was added dropꢀwise to a solution of
diphenylmethane 6 diphenylmethane (8.0 g, 47.59 mmol) in dry THF (350 mL) at 0
oC under nitrogen atmosphere. The resulting mixture was stirred for additional 2 h at
0 oC. Then to it was added a solution of 5 (9.76 g, 37.59 mmol) in THF (60 mL) and
the mixture was allowed to stir at room temperature for 10 h. Completion of the
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 22 of 28
1
2
3
4
5
6
7
8
9
reaction was monitored by TLC analysis. After completion, reaction mixture was
quenched by adding aqueous solution of ammonium chloride then the mixture and
extracted with DCM (3×50 mL). Organic layer was dried over anhydrous magnesium
sulphate and evaporated on rotavapour to give crude alcohol intermediate. This crude
intermediate was then dissolved in toluene (100 mL) and pꢀtoluenesulfonic acid
(PTSA, 2 g) was added to it and refluxed for 16 h. After completion reaction mixture
was cooled to rt. Reaction mixture was evaporated on rotavapour to give crude
residue which was purified by silica gel chromatography (40ꢀ60 nm) with nꢀhexane to
give analytical pure compound 4 as white solid in 83% yield (16.3 g). All the data
matches with reported compound 4. 1HNMR (300 MHz, CDCl3) δ ppm: 7.27ꢀ7.21 (d,
2H, J = 6.0 Hz), 7.17ꢀ7.09 (m, 9H), 7.08ꢀ7.00 (m, 6H), 6.95ꢀ6.89 (d, 2H, J = 6.0 HZ).
Synthesis of 5ꢀ(4ꢀ(1, 2, 2ꢀtriphenylvinyl) phenyl) thiopheneꢀ2ꢀcarbaldehyde (3).
Compound 4 (3.0 g, 7.30 mmol) was added to a solution of dimethyloxyethane
(DME): 2 M Na2CO3 solution (3:1, 100 mL) under argon atmosphere followed by
addition of (5ꢀformylthiophenꢀ2ꢀyl)boronic acid (1.48 g, 9.51 mmol) and resulting
reaction mixture was degassed for 15 min using argon. Then Pd(PPh3)4 (0.253 g, 0.21
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
o
mmol) was added and resultant mixture was heated to reflux at 150 C for 24 h.
Completion of the reactions was monitored by TLC analysis. After completion,
reaction was quenched with water and extracted with DCM (3x75 mL). The combined
organic layer was washed with water, dried over anhydrous sodium sulphate and
evaporated. Crude residue was purified by silica gel column chromatography and
column was eluted with 5% MeOH in DCM, gives 3 as a yellow solid in 62% yield
1
(2.0 g). HNMR (300 MHz, CDCl3) δ ppm: 9.8 (s, 1H), 7.62 (d, 1H, J = 3.9 Hz),
7.36ꢀ7.32 (d, 2H, J = 8.7 Hz), 7.26 (d, 1H, J = 4.2 Hz), 7.08ꢀ6.93 (m, 17H); 13CNMR
(75 MHz, CDCl3) δ ppm: 182.7, 154.2, 145.3, 143.3, 143.2, 141.9, 149.9, 137.4,
ACS Paragon Plus Environment

Page 23 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
132.1, 131.4, 131.3, 131.2, 127.9, 127.8, 127.6, 126.7, 126.6, 125.6, 123.8; Anal.
Calcd for C31H22OS: C, 84.13; H, 5.01. Found: C, 84.14; H, 5.01.
7
8
9
Synthesis of 5, 10, 15, 20ꢀtetrakis (5ꢀ(4ꢀ(1, 2, 2ꢀtriphenylvinyl)phenyl) thiophenꢀ2ꢀ
yl) porphyrin (1). Condensation of 3 (1.0 g, 2.25 mmol) with equimolar amount of
pyrrole (0.156 mL, 2.25 mmol) was heated in propionic acid (100 mL) at reflux
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
o
temperature for 1 h. Thereafter, resulting mixture was allowed to cool at 0 C for 30
min. Black colour solid residue was filtered through Buchner funnel. Solid residue
was washed with MeOH and crude residue was purified by silica gel column
chromatography with 50% DCM in hexane to give pure compound as a blackish
1
compound in 7% yield (0.3 g). HNMR (300 MHz, CDCl3) δ ppm: 9.09 (s, 2H), 7.75
(d, 1H, J = 3.6 Hz), 7.59 (d, 1H, J = 3.6 Hz), 7.57ꢀ7.51 (d, 2H, 8.4 Hz), 7.16ꢀ6.98 (m,
13
18H), ꢀ2.60 (bs, 2H); CNMR (75 MHz, CDCl3) δ ppm: 147.0, 143.7, 143.6, 141.7,
141.3, 140.4, 132.2, 132.1, 131.4, 131.3, 127.9, 127.7, 127.6, 126.6, 124.9, 122.0
Anal. Calcd for C140H94N4S4: C, 85.77; H, 4.83; N, 2.86. Found: C, 85.75; H, 4.81; N
2.84.
Synthesis of zincꢀ5, 10, 15, 20ꢀtetrakis (5ꢀ(4ꢀ(1, 2, 2ꢀtriphenylvinyl)phenyl)
thiophenꢀ2ꢀyl)porphyrin (2). To a stirred solution of TPEꢀporphyrin 1 (0.1 g, 0.051
mmol) in CHCl3 (20 mL) was added solution of Zn(OAc)2 (0.1 g) in MeOH (2 mL)
and resultant was allowed to stir at rt for 16 h. Reaction completion was checked by
TLC analysis with spot disappearance of 1. After completion, reaction mixture was
evaporated on rotaryꢀevaporator to complete dryness and crude residue obtained was
purified by silica gel column chromatography. Compound 2 was eluted in 50% DCM
1
in hexane as blackish solid in 48% yield (0.050 g). HNMR (300 MHz, CDCl3) δ
ppm: 9.20 (s, 2H), 7.74 (d, 1H, J = 3.6 Hz), 7.60 (d, 1H, J = 3.6 Hz), 7.56 (d, 2H, J =
8.1 Hz), 7.16ꢀ6.98 (m, 19H); 13CNMR (75 MHz, CDCl3) δ ppm: 151.2, 143.7, 143.6,
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 24 of 28
1
2
3
4
5
6
143.4, 141.4, 132.1, 131.5, 131.4, 127.9, 127.7, 126.6, 124.9, 122.0; Anal. Calcd for
C140H92N4S4Zn: C, 83.08; H, 4.58; N, 2.77. Found: C, 83.09; H, 4.59; N 2.79.
7
ASSOCITATED CONTENT
8
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
Supporting Information
SEM images solvent dependent selfꢀassembly, cyclic voltammograms, copies of
NMR (1H and 13C) and Maldi spectra of compounds 1, 2 and 3 and crystallographic
data of 3. Separate Xꢀray crystallographic data (CIF file) also has been added as
separate Supporting Information. This material is available free of charge via the
Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
*S.V.B.:
fax:
0061399252680;
Tel:
0061399252680;
eꢀmail:
sheshanath.bhosale@rmit.edu.au
Notes
The authors declare no competing financial interest.
ACKNOWLEDGEMENTS
S.V.B. (RMIT) acknowledges the Australian Research Council for financial support
under a Future Fellowship Scheme (FT110100152) and the RMIT Microscopy and
Microanalysis Facility (RMMF). SVB (IICT) is grateful for financial support from the
CSIRꢀIntel Coat (CSC 0114) programme. L.A.J. acknowledges receipt of a Vice
Chancellors (Industry) fellowship from RMIT University.
REFERENCES AND FOOTNOTE
(1) Whitesides, G. M.; Simanek, E. E.; Mathias, J. P.; Seto, C. T.; Chin, D. N.;
Mammen, M.; Gordon, D. M. Acc. Chem. Res. 1995, 28, 37.
ACS Paragon Plus Environment

Page 25 of 28
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
(2) Lehn, J. ꢀM. Angew. Chem., Int. Ed. 1990, 29, 1304.
(3) Zuber, H.; Brunisholz, R. A. Chlorophylls, Scheer, H. Ed., CRC Press: Boca
Raton, Florida, 1991; pp 627.
9
(4) Jones, R.; Tredgold, R. H.; Hoorfar, A.; Hodge, P. Thin Solid Films 1984, 113,
115.
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
(5) Campidelli, S.; Sooambar, C.; Diz, E. L.; Ehli, C.; Guldi, D. M.; Prato, M. J.
Am. Chem. Soc. 2006, 128, 12544.
(6) Imahori, H.; Fukuzumi, S. Adv. Funct. Mater. 2004, 14, 525.
(7) Nagata, N.; Kuramochi, Y.; Kobuke, Y. J. Am. Chem. Soc. 2009, 131, 10.
(8) Williams, F. J.; Vaughan, O. P. H.; Knox, K. J.; Bampos, N.; Lambert, R. M.
Chem. Commun. 2004, 1688.
(9) Bhosale, S. V.; Bhosale, S. V.; Kalyankar, M. B.; Langford, S. J.; Lalander C.
H. Aus. J. Chem. 2010, 63, 1326.
(10) Bhosale, S. V.; Chong, C.; Forsyth, C.; Langford, S. J.; Woodward, C. P.;
Tetrahedron 2008, 64, 8394.
(11)Bhosale, S. V.; Bissett, M. A.; Forsyth, C.; Langford, S. J.; Neville, S. M.;
Shapter, J. G.; Weeks, L.; Woodward, C. P. Org. Lett. 2008, 10, 2943.
(12)Wang, Z. C.; Li, Z. Y.; Medforth, C. J.; Shelnutt, J. A. J. Am. Chem. Soc.
2007, 129, 2440.
(13)Lee, S. J.; Hupp, J. T.; Nguyen, S. T. J. Am. Chem. Soc. 2008, 130, 9632.
(14)Guo, P. P.; Chen, P. L.; Liu, M. H. Langmuir 2012, 28, 15482.
(15)Tretiak, S.; Middleton, C.; Chernyak, V.; Mukamel, S. J. Phys. Chem. B 2000,
104, 9540.
(16)Takazawa, K. Chem. Mater. 2007, 19, 5293.
(17)Schenning, A. P. H. J.; Benneker, F. B. G.; Geurts, H. P. M.; Liu, X.Y.;
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 26 of 28
1
2
3
4
Nolte, R. J. M. J. Am. Chem. Soc. 1996, 118, 8549.
5
6
7
8
(18)McDermott, G.; Prince, S. M.; Freer, A. A.; HawthormthwaiteꢀLawless, A.
M.; Papiz, M. Z.; Cogdell, R. J.; Isaacs, N. W. Nature 1995, 374, 517.
(19)Guest, D.; Moore, T. A.; Moore, A. L. Acc. Chem. Res. 2009, 42, 1890.
(20)Aratani, N.; Kim, D.; Osuka, A. Acc. Chem. Res. 2009, 42, 1922.
(21)Albinsson, B.; Mårtensson, J. J. Photochem. Photobiol. C: Photochem. Rev.
2008, 9, 138.
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
(22)Senge, O. M.; Fazekas, M.; Notaras, E. G. A.; Blau, W. J.; Zawadzka,
M.; Locos, O. B.; Mhuircheartaigh, E. M. Adv. Mater. 2007, 19, 2737.
(23)Herrero, C.; LassalleꢀKaiser, B.; Leibl, W.; Rutherford, A. W.; Aukauloo A.
Coord. Chem. Rev. 2008, 252, 456.
(24)Hiraku, Y.; Ito, K.; Hirakawa, K.; Kawanishi, S. Photochem. Photobiol. 2007,
83, 205ꢀ212.
(25) Giribabu, L.; Kanaparthi, R. K.; Velkannan, V. Chem. Rec. 2012, 12, 306.
(26) Yushchenko, O.; Hangarge, R. H.; MosqueraꢀVazquez, S.; Bhosale, S. V.;
Vauthey, E. J. Phys. Chem. B 2014, DOI: 10.1021/jp5108685.
(27) Wasielewski, M. R. Acc. Chem. Res. 2009, 42, 1910.
(28) Davis, D. A.; Hamilton, A.; Yang, J. L.; Cremar, L. D.; Van Gough, D.;
Potisek, S. L.; Ong, M. T.; Braun, P. V.; Martinez, T. J.; White, S. R.; Moore, J. S.;
Sottos, N. R. Nature 2009, 459, 68.
(29) Kwon, M. S.; Gierschner, J.; Yoon, S. J.; Park, S. Y. Adv. Mater. 2012, 24,
5487.
(30) Li, Z.; Dong, Y. Q.; Lam, J. W. Y.; Sun, J. X.; Qin, A. J.; Haussler, M.; Dong,
Y. P.; Sung, H. H. Y.; Williams, I. D.; Kwok, H. S.; Tang, B. Z. Adv. Funct. Mater.
2009, 19, 905.
ACS Paragon Plus Environment

Page 27 of 28
The Journal of Organic Chemistry
1
2
3
4
(31) Wang, M.; Zhang, D. Q.; Zhang, G. X.; Zhu, D. B. Chem. Commun. 2008,
5
6
4469.
7
8
9
(32) Luo, J.; Xie, Z.; Lam, J. W. Y.; Cheng, L.; Chen, H.; Qiu, C.; Kwok, H. S.;
Zhan,X.; Liu, Y.; Zhu, D.; Tang, B. Z. Chem. Commun. 2001, 1740.
(33) Zeng, Q.; Li, Z.; Dong, Y.; Di, C. A.; Qin, A.; Hong, Y.; Ji, L.; Zhu, Z.; Jim,
C. K. W.; Yu, G.; Li, Q.; Li, Z.; Liu, Y.; Qin, J.; Tang, B. Z. Chem. Commun. 2007,
70.
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
(34) Tong, H.; Hong, Y.; Dong, Y.; Haussler, M.; Li, Z.; Lam, J. W. Y.; Dong, Y.;
Sung, H. H. Y.; Williams, I. D.; Tang, B. Z. J. Phys. Chem. B 2007, 111, 11817.
(35) Shi, H.; Kwok, R. T. K.; Liu, J.; Xing, B.; Tang, B. Z.; Liu, B. J. Am. Chem.
Soc. 2012, 134, 17972.
(36) Kapadia, P. P.; Widen, J. C.; Magnus, M. A.; Swenson, D. C.; Pigge, F. C.
Tetrahedron Lett. 2011, 52, 2519.
(37) Zheng, Y. ꢀR.; Zhao, Z.; Wang, M.; Ghosh, K.; Pollock, J. B.; Cook, T.
R.; Stang, P. J. J. Am. Chem. Soc. 2010, 132, 16873.
(38) Rananaware, A.; Bhosale, R. S.; Patil, H.; Al Kobaisi, M.; Abraham, A.;
Shukla, R.; Bhosale, S. V.; Bhosale, S. V. RSC Adv. 2014, 4, 59078.
(39) Rochford, J.; Botchway, S.; McGarvey, J. J.; Ronney, A. D.; Pryce, M. T. J.
Phys. Chem. A 2008, 112, 11611.
(40) Minch, B. A.; Xiz, W.; Donley, C. L. Hernandex, R. M.; Carter, C.;
Carducci, M. D.; Dawson, A.; O’Brien, D. F.; Armstrong, R. R. Chem. Mater. 2005,
17, 1618.
(41) Kaiser, T. E.; Wang, H.; Stepanenko, V.; Würthner, F. Angew. Chem., Int. Ed.
2007, 46, 5541.
(42) Kadish, K. M.; Caemelbecke, E. V. J. Solid State Electrochem. 2003, 7, 254.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 28 of 28
1
2
3
4
5
6
7
8
9
(43) Mussini, P. R.; Biroli, A. O.; Tessore, F.; Pizzotti, M.; Biaggi, C.; Carlo, G.
D.; Lobello, M. G.; Angelis, F. D. Electrochimica Acta. 2012, 85, 509.
(44) Ohkubo, K.; Sintic, P. J.; Tkachenko, N. V.; Lemmetyinen, H.; E, W.; Ou, Z.;
Shao, J.; Kadish, K. M.; Crossley, M. J.; Fukuzumi, S. Chem. Phys. 2006, 326, 3.
(45) Horiuchi, H.; Tanaka, T.; Yoshimura, K.; Sato, K.; Kyushin, S.; Matsumoto,
H.; Hiratsuka, H. Chem. Lett. 2006, 35, 662.
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
(46) Larsen, J.; Brüggemann, B.; Polívka, T.; Sundström, V.; Åkesson, E.; Sly, J.;
Crossley, M. J. J. Phys. Chem. A 2005, 109, 10654.
(47) Crystal data for TPEꢀaldehyde 3: C31H22O1S1, M= 442.55, 0.767 x 0.137 x
0.087mm3, monoclinic space group P21, a = 5.5812(7), b = 47.120(6), c =
9.2435(11) Å, α = 90 β = 103.343(3) ϒ = 90, V = 2365.3(5), Z = 4 Dc = 1.243 g/cm3,
F000 = 928, T = 200(2) K, 1.73< θ < 33.92o, 19180 reflection collected, 19180 unique
(Rint = 0.0972) Final GoF = 1.028 R1 = 0.0659, wR2 = 0.1531, R indices based on
18751 reflections with I >2σ(I) (refinement on F2), 595 parameters.Crystallographic
data for TPEꢀaldehyde 3 have been deposited with the Cambridge Crystallographic
Data Centre as supplementary publication No. CCDCꢀ 1037259. Copies of the data
can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge
CB21EZ, UK. Fax: (+44)1223ꢀ336ꢀ033; Eꢀmail:deposit@ccdc.cam.ac.uk).
(48) Pullerits, T.; Sundström, V. Acc. Chem. Res. 1996, 29, 381.
(49) Banerjee, M.; Emond, S. J.; Lindeman, S. V.; Rathore, R. J. Org. Chem. 2007,
72, 8054.
ACS Paragon Plus Environment