Polysubstituted Hexa-cata-hexabenzocoronenes: Syntheses, Characterization, and Their Potential as Semiconducting Materials in Transistor Applications

Article abstract of DOI:10.1021/acs.joc.9b00802

A series of tetra- and octa-substituted hexa-cata-hexabenzocoronenes (cata-HBCs) were synthesized from tetraryl olefins via iodine- and iron chloride-catalyzed oxidative cyclodehydrogenation reactions. The substitutions on the periphery of the parent HBC serve to modify the photophysical properties, highest occupied molecular orbital-lowest unoccupied molecular orbital gaps, and thermal stabilities of the respective derivatives. The crystal structures were determined to display multiple twists in the framework, resulting in different packing motifs depending on the position, type, and number of functional groups on the hexabenzocoronene framework. Nearly perfect co-facial packing to marginally or extensively shifted co-facial stacks were obtained due to substitution. The single crystals of parent HBC were used to fabricate single-crystal field-effect transistors, from which the highest p-channel mobility of 0.51 cm² V^-1 s^-1 was measured. Thin-film transistors of selected HBCs were also prepared, and 0.61 cm² V^-1 s^-1 was obtained for MeHBC-2. These results attest the potential of these materials as semiconducting materials.

Full text of DOI:10.1021/acs.joc.9b00802

Subscriber access provided by ALBRIGHT COLLEGE
Article
Polysubstituted Hexa-cata-Hexabenzocoronenes: Syntheses, Characterization
and Their Potential as Semiconducting Materials in Transistor Application
Sushil Kumar, Someshwar Pola, Chih-Wei Huang, Md. Minarul Islam, Samala Venkateswarlu, and Yu-Tai Tao
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.9b00802 • Publication Date (Web): 10 Jun 2019
Downloaded from http://pubs.acs.org on June 10, 2019
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 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 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.
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 27
The Journal of Organic Chemistry
Polysubstituted Hexa-cata-Hexabenzocoronenes: Syntheses, Characterization and
Their Potential as Semiconducting Materials in Transistor Application
Sushil Kumar,a Someshwar Pola,a Chih-Wei Huang,a Md. Minarul Islam,b,c Samala
Venkateswarlu,b,d and Yu-Tai Tao*,a
1
2
3
4
5
6
7
8
9
aInstitute of Chemistry, Academia Sinica, Taipei, Taiwan, 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
bTaiwan International Graduate Program, Academia Sinica, Taipei, Taiwan, 115
cDepartment of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 300
dDepartment of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
Supporting Information (SI) Placeholder
Abstract
A series of tetra- and octa-substituted hexa-cata-hexabenzocoronenes (cata-HBCs) were
synthesized from tetraryl olefins via iodine- and iron chloride-catalyzed oxidative
cyclodehydrogenation reactions. The substitutions on the periphery of the parent HBC
serve to modify the photophysical properties, HOMO‒LUMO gaps and thermal stabilities
of the respective derivatives. The crystal structures were determined to display multiple
twists in the framework, resulting different packing motifs depending on the position, type
and the number of functional groups on the hexabenzocoronene framework. Nearly perfect
cofacial packing to marginally or extensively shifted cofacial stacks were obtained due to
substitution. The single-crystals of parent HBC was used to fabricate single crystal field-
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 2 of 27
effect transistor, from which a highest p‒channel mobility of 0.51 cm2V‒1s‒1 was measured.
Thin film transistors of selected HBCs were also prepared and 0.61 cm2V-1s-1 was obtained
for MeHBC-2. These results attest the potential of these materials as semiconducting
materials.
1
2
3
4
5
6
7
8
9
Introduction
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 cyclic π-conjugated organics composed of fused benzene moieties in different shapes
and sizes have been considered as useful semiconducting materials in organic electronics,
which owes its advancement to the the availability of numerous aromatic compounds
through the diligent efforts of synthetic chemists.1 Being the ubiquitous component of
electronic devices, field-effect transistors(OFETs) based on organic semiconducting
materials are particularly important.2 Much progress has been gained in improving the
field-effect mobility of OFETs through new molecular designs and device structure
modulations over the past decade, so that devices with properties surpassing that of
amorphous silicon are not uncommon.3 However, more is to learn about the
structure/property correlation in designing new materials. Efforts to understand the
structure/property correlation are nevertheless complicated by the various grain sizes and
morphologies always involved in a deposited thin film.4 These complications might be
avoided by using single cryatals to fabricate transistor devices.
The contorted polyaromatics are of particular interest for their tendency to form co-facial
‒ stackings due to self-complementarity in molecular shape or geometry.5 The direct 
face overlap in a co-facial packing is considered beneficial to the electronic coupling,
which is a required property allowing for efficient charge transport between organic
molecules.6 Nuckolls’ group unraveled the framework of hexa-cata-hexabenzocoronene
(cata-HBC) as a potential transistor material, although the measured mobility was rather
limited (~0.02 cm2V‒1s‒1) for the thin film-based devices.7 A number of coronene-cored
ACS Paragon Plus Environment

Page 3 of 27
The Journal of Organic Chemistry
non-planar derivatives have also been studied (Chart 1), with the effect of substitutents on
the crystal packing and thus mobility examined.8 Yet the effect of substituents on the
packing of cata-HBC has not been reported.
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
Coronene
DBC
TBC
cata-HBC
DNC
TNC
peri-HBC
Chart 1. Coronene and its benzo analogues.
In this report, we present the syntheses and characterizations of a series of tetra- and octa-
substituted hexa-cata-hexabenzocoronenes (Chart 2). These are synthesized from tetra
and octaaryl olefins via oxidative cyclodehydrogenation reactions catalyzed by iodine and
iron chloride. The packing motifs of these HBCs were much influenced by the substituents
attached to the main aromatic core. Although, they had twisted polyfused frameworks, they
formed strong π-aggregates, affecting the self-assembly behavior of these molecules. The
potential of these derivatives as transistor materials were exemplified by single crystal
field-effect transistor fabricated from the parent HBC, which gave a high mobility of 0.51
cm2V‒1s‒1 and an on-off ratio of 104 ~107.
3
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Me
Page 4 of 27
R
R
Me
F
F
1
2
3
4
5
6
7
8
9
F
F
F
F
R
R
HBC:
R = H
Flu-HBC:
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
R = F
R = Cl
R = OMe
: R = Me
Me
Me-HBC2
Me
F
OFlu-HBC
F
Cl-HBC:
Met-HBC:
Me-HBC1
Chart 2. Chemical structures of synthesized HBCs.
Results and Discussion
Syntheses
The syntheses of substituted HBCs are illustrated in Schemes 1, 2, and 3. The 6,13-
bis(dibromomethylene)-6,13-dihydropentacene (1) was prepared via known synthetic
protocol.9 Multifold Suzuki coupling reactions were carried out on 1 to afford polyaryl
olefins (2–8). These polyaryl olefins were subjected to oxidative cyclodehydrogenation
reactions by first irradiating the solutions of polyaryl olefins and iodine with UV-light,10
and then treating the resulted partially annulated derivatives with iron chloride11 to furnish
the substituted HBCs in high yields (Table 1, entries 1–6).
R1
R1
R1
R1
Br Br
A
B
Br Br
1
R1
2:
3:
4:
5:
6:
R1
R1 and R3 = H
R1 = H, R2 = F
R1 = H, R2 = Cl
R1 = H, R2 = OMe
R1 = H, R2 = Me
R1
R1
A
B
= Pd(PPh3)2Cl2/PPh3
Aq. K2CO3/toluene,
reflux, 12 h
HBC:
Flu-HBC:
Cl-HBC:
Met-HBC:
Me-HBC1:
R1 = H
R1 = F
R1 = Cl
R1 = OMe
R1 = Me
R1
B(OH)2
= 1. I2/methyloxirane
toluene (UV-Light), 1024 h
2. FeCl3/DCM
8 h
MeNO2, 2
4
ACS Paragon Plus Environment

Page 5 of 27
The Journal of Organic Chemistry
Scheme 1. Preparation of 3,10,15,22-tetrasubstituted hexabenzo[a,d,g,j,m,p]coronenes (HBC, Flu-
HBC, Cl-HBC, Met-HBC and Me-HBC1).
1
2
3
4
5
Me
Me
Me
Me
6
7
8
Br Br
A
B
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
Br Br
1
A
B
= Pd(PPh3)2Cl2/PPh3
Me
Me
Me
Me-HBC2
Me
7
Aq. K2CO3/toluene, reflux, 12 h
B(OH)2
Me
= 1. I2/methyloxirane
toluene (UV-Light), rt, 12 h
2. FeCl3/DCM
MeNO2, rt, 4 h
Scheme 2. Preparation of 2,11,14,23-tetramethylhexabenzo[a,d,g,j,m,p]coronene (Me-
HBC2).
F
F
F
F
Br Br
F
F
F
F
F
F
F
F
A
B
Br Br
1
8
A
B
= Pd(PPh3)2Cl2/PPh3
F
F
F
F
Aq. K2CO3/toluene, reflux, 12 h
F
OFlu-HBC
B(OH)2
F
= 1. I2/methyloxirane
toluene (UV-Light), rt, 36 h
Scheme 3. Preparation of 2,4,9,11,14,16,21,23-octafluorohexabenzo[a,d,g,j,m,p]
coronene (OFlu-HBC).
It is noted that the reactivity of the tetraaryl olefin toward oxidative
cyclodehydrogenation12 depended on the functional groups attached to polyaryl olefin, as
manifested by the diverse reaction times and reaction yields of the final cata-HBCs (Table
1, entries 1‒7). Presumably because the functional groups stabilize the reaction
5
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 6 of 27
intermediates13 to different extent during their conversion to the final products.
Interestingly, the octafluoro-substituted tetraaryl olefin 8 led to complete annulation
product via iodine-mediated oxidative cyclodehydrogenation reaction, forming OFlu-
HBC, although this reaction took the longest reaction time of 36 h compared to the iodine
reactions of other derivatives (Table 1, entry 7).
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
Table 1. conversions of aryl olefins to the HBCs.
entry olefin
product
reaction timea
(h)
reaction
yieldb
(%)
Iodine-
Iron
catalyzed chloride-
reaction catalyzed
reaction
1
2
3
4
5
6
7
2
3
4
5
6
7
8
HBC
Flu-HBC
Cl-HBC
Met-HBC
Me-HBC1
Me-HBC2
OFlu-HBC
10
24
24
10
10
12
36
4
8
8
2
4
4
88
81
90
94
88
90
76d
c
-
areaction time for iodine and iron chloride-catalyzed oxidative cyclodehydrogenation
reactions. breaction yields for iron chloride-catalyzed reactions. ciron chloride was not used
d
in this case, as the iodine reaction led to complete annulation. reaction yield for iodine-
catalyzed reaction.
Single-crystal X–ray analyses
The single crystals of various cata-HBCs were obtained by using physical vapor transfer
technique (PVT) at the temperature range of 400–500 °C. The HBCs gave needle-like or
platellet-like crystals in the PVT process.14
The single-crystal X–ray analyses (Figure S23, SI, showing thermal ellipsoid plots)
revealed the packing motifs of HBCs as well as detailed features including geometry of
their frameworks, twisting angles, plane-to-plane and centroid-to-centroid distances, which
were parameters related to the electronic coupling.8c,15 As can be seen from their molecular
structures, these derivatives showed multiple twists at the periphery, where six benzene
6
ACS Paragon Plus Environment

Page 7 of 27
The Journal of Organic Chemistry
rings bent up and down alternately with respect to the central coronene part, with contortion
angles varying from 22.2° to 28.5° (Figure 1). Among the six peripheral benzenes, the four
benzenes substituted by different groups (fused at a–, d–, j–, and m–positions at the
coronene moiety) displayed different contortion angles with respect to the other two
benzenes (fused at g– and p–positions), presumably due to the electronic and steric effects
exerted by different functional groups.
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
(a) Me-HBC2
(b) HBC
(c) Flu-HBC
(e) Met-HBC
(f) Me-HBC1
(d) Cl-HBC
(h) OFlu-HBC
(g) Me-HBC2
Figure 1. (a) molecular structure of Me-HBC2, showing positions (a‒, d‒, g‒, j‒, m‒
and p‒) of six benzene rings fused with the central coronene. (b)–(g) twist angles of HBCs
measured for the peripheral benzenes (red-colored) with respect to central benzene (black-
colored).
7
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 8 of 27
In terms of packing, the severely twisted molecuels pack in several modes, depending on
the substituent. The Cl-HBC is the only one adopting exactly co-facial packing,
presumably the Cl…Cl interaction16 plays the role to bring the molecules to on-top
arrangement (Figure 2e,f). For HBC, Flu-HBC, OFlu-HBC, and Me-HBC2, similar
shifted packing mode with one molecule inserted nearly halfway between two co-facially
aligned molecules (Figure 2) was obtained. The Me-HBC1 and Met-HBC adopt different
packing with much tilted moleculear orientation. Interestingly, molecules Cl-HBC, Me-
HBC1, Met-HBC, and OFlu-HBC were found to be chiral, exhibiting two mirror image
forms (enantiomers). The π–π stacking distance (measured from the closest distance from
two overlapping  rings, shown in Figures 2a, c, e, i, k, and m) and centroid-to-centroid
distances for HBCs (measured from the centers of two cofacially stacked molecules shown
in Figure S24, SI) are given in the Table 2. These derivatives gave π–π stacking distance
of 3.274 Å to 3.367 Å, with the four fluorine- and eight fluorine-funtionalized HBCs
having the smallest and the largest coupling distance of 3.4 Å and 4.1 Å, respectively.
Although, the derivatives Me-HBC1 and Me-HBC2 are different in the positions of methyl
groups on the parent HBC, they display closer stacking distance of 3.284 Å and 3.293 Å.
Table 2. Cell parameters, π–π stacking and centroid-to-centroid distances for the single
crystals of HBCs.
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
Cell
Parameters
a (Å)
Flu-HBC
Cl-HBC
Met-HBC
Me-HBC1
Me-HBC2 OFlu-
HBC
12.59
7.89
14.17
90
90.1
90
4.10
14.23
27.38
94.4
90.7
97.7
9.95
13.09
14.46
113.9
103.3
92.3
10.95
14.40
11.15
90
115.1
90
15.32
12.95
16.53
90
26.54
8.06
14.58
90
b (Å)
c (Å)
α (°)
β (°)
90.4
90
103.9
90
γ (°)
Point group
adπ–π (Å)
bdc–c (Å)
P1/c
3.274
7.737
P–1
3.341
3.341
P–1
3.309
8.301
P21/c
3.284
14.717
P21/n
3.293
10.130
P 1 21/c 1
3.367
7.804
aπ–π coupling distance. bcentroid-to-centroid distance.
8
ACS Paragon Plus Environment

Page 9 of 27
The Journal of Organic Chemistry
1
2
3
4
5
6
7
8
9
(b)
(a)
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
(d)
(c)
(e)
(f)
(g)
(h)
(i)
(j)
9
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 10 of 27
1
2
3
4
5
6
7
8
9
(k)
(l)
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
(m)
(n)
Figure 2. Packing motifs of HBCs: (a)–(b) HBC, (c)–(d) Flu-HBC, (e)–(f) Cl-HBC, (g)–
(h) Met-HBC, (i)–(j) Me-HBC1, (k)–(l) Me-HBC2 and (m)-(n) OFlu-HBC
As shown in Figure 3, Flu-HBC, Cl-HBC and Met-HBC were able to develop strong
contacts17 CF…HC, CCl…HC, CO…HC at the interatomic distances of 2.45 Å to 2.92 Å.
These interactions were able to hold nearby molecules providing a regular packing motifs
to these polyaromatics.
(b) Cl-HBC
(a) Flu-HBC
(c) Met-HBC
(d) OFlu-HBC
10
ACS Paragon Plus Environment

Page 11 of 27
The Journal of Organic Chemistry
1
2
3
4
Figure 3. Packing motifs of HBCs showing CF…HC, CCl…HC and CO…HC
5
6
7
interactions.
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
Since the molecular arrangement in polyaromatics has important impact on electronic
coupling, which in turn affect the charge transporting properties of single-crystals. The
twisted geometry and attached functional groups of these HBCs were considered to be
effective features in affecting their electro-optical properties.
Photophysical, HOMO-LUMO, and Thermogravimetric studies
The HBCs displayed yellow to yellow-orange colors in their solid states. The electronic
absorption spectra of the benzocoronenes are displayed in the Figure 4 and S24 (SI), while
the related data are listed in the Table 3. The parent coronene exhibited three absorption
bands located at the 220 nm, 340 nm and 350 nm.18 The absorption profiles of the
tetrasubstituted coronenes stemmed from the central coronene as suggested by the spatial
distribution of their HOMOs. Functional groups such as chlorine, methyl and methoxy
groups slightly shifted the absorption toward longer wavelength, whereas fluorine groups
shifted it to shorter wavelength. As expected, HBCs showed red-shifted absorption with
respect to less extended systems of TBC and DBC derivatives.8a, 8b
11
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 12 of 27
1.2
0.9
0.6
0.3
0.0
1
2
3
4
5
6
7
8
HBC
Me-HBC1
Cl-HBC
Met-HBC
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
250
300
350
400
450
500
wavelength (nm)
Figure 4. UV-Visible spectra of HBCs as recorded in dichloromethane.
Due to poor solubilty of HBCs in organic solvents, the cyclic voltammetric
measurements were not successful. The HOMO energies of these derivatives were thereby
obtained using photoelectron spectrometer (AC‒2) (Table 3). Theoretically calculated
HOMOs of these HBCs were mainly centralized on coronene unit, which possibly affected
the oxidation potentials of designed coronenes (Figure 5). Substituting parent HBC by the
electron donors and electron acceptors affected their HOMO energies. For example, Met-
HBC and OFlu-HBC have the highest-lying and lowest-lying HOMO energies
respectively in this HBC series (Table 3).The weak donor methyl groups at different
positions of HBC framework cause the HOMO values to fall in between. The optical band
gaps of these benzocoronenes were estimated from their absorption band edges, which on
substrating from EHOMO provided the ELUMO values. Similar to the HOMO energies, the
LUMO energies were also perturbed by the attached functional groups. Therefore, the
introduction of fluorine or chlorine atoms lowered the LUMO energy levels in HBCs.
12
ACS Paragon Plus Environment

Page 13 of 27
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 5. Forntier molecular orbitals and respective measured energies for HBCs: HOMO
(bottom), LUMO (top).
Table 3. Energy of HOMO, LUMO, band gap and thermogravimetric data of HBCs.
c
Compd.
HBC
aλabs bEHOMO ELUMO dEg
eTd
(nm)
371
(eV)
5.22
(eV)
2.72
(eV) (°C)
2.50
2.45
2.44
2.58
2.62
2.64
2.98
516
488
532
498
469
528
486
(max),
265
Flu-HBC
Cl-HBC
370
(max),
263
375
(max),
268
380
(max),
266
372
(max),
268
374,
271
(max)
378,
262
5.63
5.53
5.06
5.12
5.16
5.76
3.18
3.09
2.48
2.50
2.52
2.78
Met-HBC
Me-HBC1
Me-HBC2
OFlu-HBC
(max)
b
aAbsorption wavelengths. EHOMO measured by photoelectron spectrometer (AC‒2).
d
cELUMO = EHOMO − Eg. Optical bandgap, Eg, was obtained from the absorption edge.
eThermal decomposition temperature measured at 5% weight loss.
Thermal stability of these HBCs is evaluated by their thermogravimetric analyses, whose
results are given in Figure S25‒S26, (SI), while their values are compiled in Table 3. The
ACS Paragon Plus Environment
13

The Journal of Organic Chemistry
Page 14 of 27
thermal decomposition temperatures of these HBCs were obtained at 5% weight loss. The
1
2
3
°
thermal decomposition temperatures of these polyaromatics were as high as 516 C and
4
5
6
7
were not lower than 469 °C. Thus, stable transistor devices could be prepared from these
derivatives.19
8
9
SCFET performance
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
To evaluate the potential of this series of compounds as channel material for field-effect
transistor, single crystal field-effect transistors (SCFETs) were fabricated with the parent
HBC crystals, as it generated crystals of adequate sizes. A heavily n-doped silicon substrate
covered with 300 nm SiO2 on top was used as the gate and the dielectric insulator. A self-
assembled monolayer (SAM) of octadecyltricholorosilane (ODTS) was formed on the SiO2
surface to remove the trapping sites due to hydroxyl groups. Previous report showed that
pre-rubbing of the SAM would improve the performance of the transistor.20 Thus single
crystals of HBC were laminated on the surfaces of bare SiO2, ODTS/SiO2 and rubbed
ODTS/SiO2 substrates and gold was deposited through a mask to serve as the source and
drain electrodes. The output and transfer characteristics of SCFETs on bare SiO2,
unrubbed-ODTS/SiO2, and rubbed-ODTS/SiO2 substrates are shown in Figure 6. The
related data is given in Table 4. A typical p‒type behaviour was observed. The carrier
mobilities, as calculated from the saturation regime of current-voltage curves, showed that
a highest mobility of 0.51 cm2V‒1s‒1 was observed for device on rubbed ODTS/SiO2, while
0.27 and 0.084 cm2V‒1s‒1 were observed for devices on un-rubbed ODTS/SiO2 and bare
SiO2, respectively. Thin film field-effect transistors were also prepared for selected HBCs
such as Cl-HBC and Me-HBC2 on ODTS-modified SiO2 surfaces in a top-contact,
bottom-gate configuration. Again a better performance was in general obtained on rubbed
ODTS/SiO2 surface. As shown in Table 5, a high mobility of 0.61 cm2V-1s-1 was obtained
for MeHBC-2 deposited at 70 C, whereas for Cl-HBC, the value of mobility was recorded
to be 0.24 cm2V-1s-1, even though an exact cofacial packing is found for Cl-HBC.
14
ACS Paragon Plus Environment

Page 15 of 27
The Journal of Organic Chemistry
The morphology/grain size will play a major role in the case of thin film devices.
The data nevertheless also demonstrate the potential of these molecules as transistor
materials.
1
2
3
4
5
6
7
8
9
(a)
With bare SiO2
(b) With unr-ODTS
-15.0
-10.0
-5.0
-30.0
-20.0
-10.0
0.0
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
0.0
0
-20
-40
-60
-80
0
-20
-40
-60
-80
Vd (V)
Vd (V)
0.006
(c) With rub-ODTS
Bare SiO2
unr-ODTS
rub-ODTS
(d)
1E-5
1E-6
-90
-60
-30
0
0.004
0.002
0.000
1E-7
1E-8
1E-9
1E-10
1E-11
1E-12
0
-20
-40
-60
-80
40 20
0
-20 -40 -60 -80
Vd (V)
Vd (V)
Figure 6. (a)-(c) Output SCFET characteristics of compound HBC. (d) transfer
characteristics on bare SiO2, unrubbed ODTS/SiO2 and rubbed ODTS/SiO2.
Table 4. SCFET data of HBC at the SiO2, unrubbed-ODTS and rubbed-ODTS surfaces
SAM
Mobility
(cm2 V‒1 s‒1)
0.028 – 0.084
0.16 – 0.27
0.34 – 0.51
On/off ratio
Vth
(V)
SiO2
105 – 106
105 – 108
105 – 107
-10 – (-17)
-21 – (-32)
-12 – (-20)
ODTS
rub-ODTS
15
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Table 5. Thin-film transistors characteristics for HBCs deposited on rubbed-ODTS
surfaces at 70C.
Page 16 of 27
1
2
3
4
5
6
7
8
Compd
Mobility
(cm2 V-1 s-1)
0.38 – 0.42
0.22 – 0.24
0.59 – 0.61
On/off ratio
Vth
(V)
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
HBC
105
106
106
-21 – (-23)
-23 – (-24)
-12 – (-14)
Cl-HBC
MeHBC-2
Conclusions
In conclusion, we have successfully synthesized and characterized a series of substituted
hexa-cata-hexabenzocoronenes HBCs. The substitution affects the physical properties
such as oxidation potential and UV absorption to a small extent but affects the crystal
packing to a larger extent. Single-crystal X–ray analyses showed different extents of twist
angle for the peripheral benzene rings aound the coronene core, depending on the
substitutent. Although, peripheral addition of functional groups at hexabenzocoronene did
not affect much the distortions at the fjords, they changed the packing pattern, due to the
size, dipole and/or heteroatom interactions. The parent HBC afforded a p–type field-effect
mobility in the range of 0.34~0.51 cm2V‒1s‒1, with an on/off ratio of 105–107. Thin film
transistors based on MeHBC-2 gave a highest mobility of 0.61 cm2V-1s-1 and an on/off
ratio of 106. These characteristics demonstrate the potential of HBC derivatives as
conducting channel for transistor application.
Experimental Section
The required starting materials were commercially available and used without further
purification. The Suzuki coupling, iodine- and iron chloride-mediated oxidative
cyclodehydrogenation reactions were conducted under nitrogen atmosphere. The prefinal
16
ACS Paragon Plus Environment

Page 17 of 27
The Journal of Organic Chemistry
tetraaryl olefins were purified by column chromatography using silica gel with 60–230
1
2
3
4
5
6
7
8
9
1
13
mesh size. H and C NMR spectra were recorded on a Bruker AMX400 O FT-NMR
spectrometer in deuterated solvents like chloroform-d and benzene-d6, using
tetramethylsilane (TMS) as the internal standard. V-550 JASCO UV/VIS
spectrophotometer was used to perform absorption studies in dried and distilled
dichloromethane. The HOMO–LUMO energy levels of selected HBCs samples were
measured using photoelectron spectrometer (AC-2) (Riken Keiki) in ambient. A
temperature-gradient copper tube, equipped with argon flow as the carrier gas, was used to
grow single crystals of HBC samples. The single-crystal X-ray diffractions were obtained
on a Bruker X8APEX X-ray diffractometer with Mo Kα radiation (λ = 0.710 73 Å), and
the structures of HBC samples were solved by the SHELX 97 program. To get HOMO–
LUMO plots, theoretical calculations were performed for HBCs by using PC Spartan Pro
software with semi-empirical methods at the AM1 level.
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
General reaction procedure for the preparation of polyaryl olefins 2–8 through
Suzuki C–C cross coupling reactions. 6,13-Bis(dibromomethylene)-6,13-
dihydropentacene (0.62 g, 1.0 mmol) (1), arylboronic acid (4.1 mmol), Pd(PPh3)2Cl2 (72
mg), PPh3 (52 mg) and potassium carbonate (1.38 g, 10.0 mmol) were taken in a mixture
of toluene (30 ml) and water (15 ml). The reaction mixture was heated at 110 ºC for 12 h
under nitrogen atmosphere. On completion of reaction, the mixture was cooled and toluene
layer was extracted. On removal of toluene, the product was purified by column
chromatography using dichloromethane/hexane as eluent.
6,13-Bis(diphenylmethylene)-6,13-dihydropentacene (2)7 Following
the general
reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-bis(dibromomethylene)-
6,13-dihydropentacene (1) using phenylboronic acid (0.50 g, 4.1 mmol) gave the title
product as white solid. Yield: 0.49 g, 80%.
17
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 18 of 27
6,13-Bis(bis(4-fluorophenyl)methylene)-6,13-dihydropentacene (3) Following the
general reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-
bis(dibromomethylene)-6,13-dihydropentacene (1) using (4-fluorophenyl)boronic acid
(0.57 g, 4.1 mmol) gave the title product as white solid. Yield: 0.53 g, 78%. mp > 350 °C.
1H NMR (CDCl3, 400 MHz) δ 7.50 (s, 4H), 7.44-7.39 (m, 12H), 7.29-7.28 (m, 4H), 6.99
(t, J = 8.4 Hz, 8H). 13C NMR (CDCl3, 400 MHz) δ 162.9, 160.4, 138.7, 138.0, 136.4, 135.5,
131.5, 131.3, 131.2, 127.7, 127.1, 125.9, 115.5, 115.3. HRMS (MALDI-TOF) m/z [M]+
calcd for C48H28F4 680.2127, found 680.2137.
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
6,13-Bis(bis(4-chlorophenyl)methylene)-6,13-dihydropentacene (4) Following the
general reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-
bis(dibromomethylene)-6,13-dihydropentacene (1) using (4-chlorophenyl)boronic acid
(0.64 g, 4.1 mmol) gave the title product as white solid. Yield: 0.63 g, 84%. mp 326‒330
°C. 1H NMR (CDCl3, 400 MHz) δ 7.52 (s, 4H), 7.46-7.45 (m, 4H), 7.36-7.45 (d, J = 7.2
Hz, 8H), 7.31-7.29 (m, 8H), 7.19 (d, J = 6.8 Hz, 4H). 13C NMR (CDCl3, 400 MHz) δ 140.2,
138.4, 136.6, 135.2, 133.0, 131.5, 131.0, 129.0, 128.2, 127.7, 127.2, 126.1, 125.3. HRMS
(MALDI-TOF) m/z [M]+ calcd for C48H28Cl4 744.0945, found 744.0934.
6,13-Bis(bis(4-methoxyphenyl)methylene)-6,13-dihydropentacene (5) Following the
general reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-
bis(dibromomethylene)-6,13-dihydropentacene (1) using 4-methoxyboronic acid (0.62 g,
4.1 mmol) gave the title product as white solid. Yield: 0.64 g, 88%. mp 266‒270 °C. 1H
NMR (CDCl3, 400 MHz) δ 7.56 (s, 4H), 7.44-7.42 (m, 4H), 7.36 (d, J = 8.4 Hz, 8H), 7.24-
7.21 (m, 4H), 6.81 (d, J = 8.8 Hz, 8H), 3.75 (s, 12H). 13C NMR (CDCl3, 400 MHz) δ 158.2,
139.9, 136.6, 135.4, 135.0, 131.5, 130.9, 127.7, 126.8, 125.3, 113.7, 55.2. HRMS
(MALDI-TOF) m/z [M]+ calcd for C52H40O4 728.2927, found 728.2934.
18
ACS Paragon Plus Environment

Page 19 of 27
The Journal of Organic Chemistry
6,13-bis(di-p-tolylmethylene)-6,13-dihydropentacene (6) Following
the general
1
2
3
4
5
6
7
8
9
reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-bis(dibromomethylene)-
6,13-dihydropentacene (1) using p-tolylboronic acid (0.56 g, 4.1 mmol) gave the title
product as white solid. Yield: 0.55 g, 82%. mp 296‒300 °C. 1H NMR (CDCl3, 400 MHz)
δ 7.55 (s, 4H), 7.42 (dd, J = 9.6 Hz 3.6 Hz, 4H), 7.37 (d, J = 7.6 Hz, 8H), 7.24-7.21 (m,
4H), 7.08 (d, J = 8.0 Hz, 8H), 2.28 (s, 12H). 13C NMR (CDCl3, 400 MHz) δ 140.8, 139.6,
136.4, 136.0, 135.4, 131.5, 129.6, 129.0, 128.9, 128.2, 127.7, 126.8, 125.3, 21.1. HRMS
(MALDI-TOF) m/z [M]+ calcd for C52H40 664.3130, found 664.3134.
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
6,13-Bis(di-m-tolylmethylene)-6,13-dihydropentacene (7) Following
the general
reaction procedure, a Suzuki C–C cross coupling reaction on 6,13-bis(dibromomethylene)-
6,13-dihydropentacene (1) using m-tolylboronic acid (0.56 g, 4.1 mmol) gave the title
product as white crystalline solid. Yield: 0.57 g, 86%. mp 268‒272 °C. 1H NMR (CDCl3,
400 MHz) δ 7.59 (s, 4H), 7.45-7.38 (m, 12H), 7.28-7.22 (m, 8H), 7.06 (d, J = 7.6 Hz, 4H),
2.34 (s, 12H). 13C NMR (CDCl3, 400 MHz) δ 142.5, 141.4, 137.9, 136.2, 135.3, 131.4,
130.2, 128.0, 127.4, 127.3, 126.7, 125.5. HRMS (MALDI-TOF) m/z [M]+ calcd for C52H40
664.3130, found 664.3133.
6,13-Bis(bis(3,5-difluorophenyl)methylene)-6,13-dihydropentacene (8) Following the
general reaction procedure, a cross Suzuki C–C coupling reaction on 6,13-
bis(dibromomethylene)-6,13-dihydropentacene (1) using 3,5-difluorophenylboronic acid
(0.65 g, 4.1 mmol) gave the title product as white crystalline solid. Yield: 0.65 g, 87%. mp
297‒301 °C. 1H NMR (CDCl3, 400 MHz) δ 7.54 (s, 4H), 7.52-7.50 (m, 4H), 7.37-7.34 (m,
13
4H), 6.98-6.95 (m, 8H), 6.70 (d, J = 8.8 Hz, 4H). C NMR (CDCl3, 400 MHz) δ 164.3,
164.2, 161.8, 161.7, 144.1, 144.0, 143.9, 137.5, 136.5, 133.9, 131.7, 127.8, 127.1, 126.6,
112.8, 112.6, 103.3, 102.8 . HRMS (MALDI-TOF) m/z [M]+ calcd for C48H24F8 752.1750,
found 752.1754.
19
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 20 of 27
General procedure for the preparations of HBCs through oxidative
cyclodehydrogenation reactions on aryl olefins Polyaryl olefin (2–8) (1.0 mmol), iodine
(2.03 g, 4.1 mmol) and methyloxirane (10 ml) were taken in toluene (30 ml). This reaction
mixture was irradiated under UV-light for 6–24 h under nitrogen atmosphere. On
completion of the reaction, excessive iodine was neutralized by treating with saturated
sodium thiosulphate solution. Removing toluene led to a mixture of partially and
completely annulated products (except polyaryl olefin 8). In case of polyaryl olefin 8,
iodine (2.03 g, 4.1 mmol) reaction led to the complete annulation.
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
A mixture of differently annulated products, obtained from polyaryl olefins 2–7, was
dissolved in anhydrous dichloromethane (60 ml). To this, a solution of iron chloride (3.24
g, 20.0 mmol) in nitromethane (10 ml) was added via a syringe. This reaction mixture was
stirred for 2–16 h under nitrogen atmosphere. On completion of reaction, the product was
precipitated on addition of methanol. The precipitated solid was filtered, washed with
methanol, hydrochloric acid, and water successively. Product was dried to give yellow to
yellow-orange solid.
Hexabenzo[a,d,g,j,m,p]coronene (HBC)7 Following the general reaction procedure, two
consecutive oxidative cyclodehydrogenation reactions on 6,13-bis(diphenylmethylene)-
6,13-dihydropentacene (2) (0.61 g, 1.0 mmol), using iodine (10 h) and iron chloride (4 h),
afforded HBC as yellow solid. Yield: 0.53 g, 88%.
3,10,15,22-Tetrafluorohexabenzo[a,d,g,j,m,p]coronene (Flu-HBC) Following
the
general reaction procedure, two consecutive oxidative cyclodehydrogenation reactions on
6,13-bis(bis(4-fluorophenyl)methylene)-6,13-dihydropentacene (3) (0.68 g, 1.0 mmol),
using iodine (24 h) and iron chloride (8 h), afforded Flu-HBC as yellow solid. Yield: 0.54
g, 81%. mp > 350 °C. 1H NMR and 13C NMR could not be recorded due to poor solubility
of this derivative. HRMS (MALDI-TOF) m/z [M]+ calcd for C48H20F4 672.1501, found
672.1506. The crystal structure was solved by X-ray diffraction.
20
ACS Paragon Plus Environment

Page 21 of 27
The Journal of Organic Chemistry
3,10,15,22-Tetrachlorohexabenzo[a,d,g,j,m,p]coronene (Cl-HBC) Following the
general reaction procedure, two consecutive oxidative cyclodehydrogenation reactions on
6,13-bis(bis(4-chlorophenyl)methylene)-6,13-dihydropentacene (4) (0.75 g, 1.0 mmol),
using iodine (24 h) and iron chloride (8 h), afforded Cl-HBC as yellow solid. Yield: 0.66
g, 90%. mp > 350 °C. 1H NMR (CDCl3, 400 MHz) δ 9.22-9.20 (m, 8H), 9.10 (d, J = 8.8
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
13
Hz, 4H), 7.94-7.92 (m, 4H), 7.82-7.80 (m, 4H). C NMR could not be recorded due to
poor solubility of this derivative. HRMS (MALDI-TOF) m/z [M]+ calcd for C48H20Cl4
736.0314, found 736.0294. The crystal structure was solved by X-ray diffraction.
3,10,15,22-Tetramethoxylhexabenzo[a,d,g,j,m,p]coronene (Met-HBC) Following the
general reaction procedure, two consecutive oxidative cyclodehydrogenation reactions on
6,13-bis(4-methoxyphenylmethylene)-6,13-dihydropentacene (6) (0.73 g, 1.0 mmol),
using iodine (10 h) and iron chloride (2 h), afforded Met-HBC as yellow solid. Yield: 0.68
g, 94%. mp > 350 °C. 1H NMR (CDCl3, 400 MHz) δ 9.34 (s, 4H), 9.11 (d, J = 8.8 Hz, 4H),
13
8.72 (s, 4H), 7.79 (s, 4H), 7.45-7.44 (m, 4H), 4.11 (m, 12H). C NMR could not be
recorded due to poor solubility of this derivative. HRMS (MALDI-TOF) m/z [M]+ calcd
for C52H32O4 720.2301, found 720.2305. The crystal structure was solved by X-ray
diffraction.
3,10,15,22-Tetramethylhexabenzo[a,d,g,j,m,p]coronene (Me-HBC1) Following the
general reaction procedure, two consecutive oxidative cyclodehydrogenation reactions on
6,13-bis(di-para-tolylmethylene)-6,13-dihydropentacene (6) (0.66 g, 1.0 mmol), using
iodine (10 h) and iron chloride (4 h), afforded the Me-HBC1 as yellow solid. Yield: 0.58
g, 88%. mp > 350 °C. 1H NMR (CDCl3, 400 MHz) δ 9.28-9.26 (m, 4H), 9.14 (d, J = 8.4
Hz, 4H), 9.06 (s, 4H), 7.83-7.81 (m, 4H), 7.65 (d, J = 8.4 Hz, 4H), 2.75 (m, 12H). 13C NMR
could not be recorded due to poor solubility of this derivative. HRMS (MALDI-TOF) m/z
[M]+ calcd for C52H32 656.2499, found 656.2502. The crystal structure was solved by X-
ray diffraction.
21
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 22 of 27
2,11,14,23-Tetramethylhexabenzo[a,d,g,j,m,p]coronene (Me-HBC2) Following the
general reaction procedure, two consecutive oxidative cyclodehydrogenation reactions on
6,13-bis(di-meta-tolylmethylene)-6,13-dihydropentacene (6) (0.66 g, 1.0 mmol), using
iodine (12 h) and iron chloride (4 h), afforded the Me-HBC2 as yellow solid. Yield: 0.59
g, 90%. mp > 350 °C. 1H NMR (CDCl3, 400 MHz) δ 9.22 (s, 4H), 9.14 (d, J = 8.8 Hz, 4H),
9.07 (s, 4H), 7.81 (m, 4H), 7.64 (d, J = 7.6 Hz, 4H), 2.74 (m, 12H). 13C NMR could not be
recorded due to poor solubility of this derivative. HRMS (MALDI-TOF) m/z [M]+ calcd
for C52H32 656.2499, found 656.2510. The crystal structure was solved by X-ray
diffraction.
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
2,4,9,11,14,16,21,23-Octafluorohexabenzo[a,d,g,j,m,p]coronene
Following the general reaction procedure, an oxidative cyclodehydrogenation reaction on
6,13-bis(bis(3,5-difluorophenyl)methylene)-6,13-dihydropentacene (6) (0.75 g, 1.0
(OFlu-HBC)
mmol), using iodine (36 h), afforded the OFlu-HBC as yellow-orange solid. Yield: 0.57
1
g, 76%. mp > 350 °C. H NMR (C6D6, 400 MHz) δ 8.52-8.46 (m, 8H), 7.55-7.52 (m, 4H),
6.91-6.89 (m, 4H). 13C NMR could not be recorded due to poor solubility of this derivative.
HRMS (MALDI-TOF) m/z [M]+ calcd for C48H16F8 744.1124, found 744.1135. The
crystal structure was solved by X-ray diffraction.
ASSOCIATED CONTENT
Supporting Information
The Supporting information is available free of charge on the ACS Publications website.
1H and 13C NMR spectra, thermal ellipsoids, additional absorption spectra,
thermogravimetric plots, theoretical calculation data, additional single-crystal field-effect
transistor data and X-ray crystallography data for the complete spectroscopic analysis
(PDF).
AUTHOR INFORMATION
Corresponding Author
22
ACS Paragon Plus Environment

Page 23 of 27
The Journal of Organic Chemistry
Prof. Yu-Tai Tao, E-mail: ytt@gate.sinica.edu.tw Fax: +886-2-27831237 Tel: +886-2-
27898580.
1
2
3
4
5
6
ACKNOWLEDGMENT
7
8
9
Financial support from Ministry of Science and Technology, Taiwan (Grant Number: 103-
2120-M-009-003-CC1) is gratefully acknowledged.
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
REFERENCES
1. (a) Wu, W.; Liu, Y.; Zhu, D. π-Conjugated molecules with fused rings for organic field-effect
transistors: design, synthesis and applications Chem. Soc. Rev. 2010, 39, 1489–1502. (b)
Wang, C.; Dong, H.; Hu, W.; Liu, Y.; Zhu, D. Semiconducting π-Conjugated Systems in
Field-Effect Transistors: A Material Odyssey of Organic Electronics
Chem.
Rev. 2012, 112, 2208–2267. (c) Baumgartner, T.; Réau, R. Chem. Rev. 2006, 106, 4681.
(d) Kumar, S.; Tao, Y.-T. Contorted Naphtho- and Fluorenocoronenes: Syntheses and
Properties of Polycyclic Aromatics beyond Benzo- and Thiophenocoronenes Org.
Lett. 2018, 20, 2320–2323. (e) Facchetti, A. π-Conjugated Polymers for Organic
Electronics and Photovoltaic Cell Applications Chem. Mater. 2011, 23, 733–758. (f)
Henkel, S.; Pollok, C. H.; Schleif, T.; Sander, W. Azulenylcarbenes: Rearrangements on
the C11 H8 Potential Energy Surface. Chem. - A Eur. J. 2016, 22, 12479–86.
2. (a) Pagliaro, M.; Ciriminna, R.; Palmisano, G. Flexible Solar Cells ChemSuschem 2008,
1, 880-891. (b) Anthony, J. E. Functionalized Acenes and Heteroacenes for Organic
Electronics Chem. Rev. 2006, 106, 5028–5048. (c) Nobusue, S.; Fujita, K.; Tobe, Y.
Skeletal Rearrangement of Twisted Polycyclic Aromatic Hydrocarbons under Scholl
Reaction Conditions, Org. Lett. 2017, 19, 3227–3230.
23
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 24 of 27
3. (a) Dimitrakopoulos, C. D.; Malenfant, P. R. L. Organic Thin Film Transistors for Large
Area Electronics Adv. Mater. 2002, 14, 99–117. (b) Podzorov, V.; Sysoev, S. E.;
Loginova, E.; Pudalov, V. M.; Gershenson, M. E. Single-crystal organic field effect
transistors with the hole mobility ∼8 cm2/Vꢀs Appl. Phys. Lett. 2003, 83, 3504–3506. (c)
Diao, Y.; Tee, B. C-K.; Giri, G.; Xu, J.; Kim, D. H.; Becerril, H. A.; Stoltenberg, R. M.;
Lee, T. H.; Xue, G.; Mannsfeld, S. C. B.; Bao, Z. Solution coating of large-area organic
semiconductor thin films with aligned single-crystalline domains Nature Mater. 2013,
12, 665–671.
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
4. Klauk, H. Organic thin-film transistors Chem. Soc. Rev. 2010, 39, 2643–2666.
5. Ball, M.; Zhong, Y.; Wu, Y.; Schenck, C.; Ng, F.; Steigerwald, M.; Xiao, S.; Nuckolls,
C. Contorted Polycyclic Aromatics Acc. Chem. Res. 2015, 48, 267–276.
6. (a) Zhang, L.; Fonari, A.; Liu, Y.; Hoyt, A.-L. M.; Lee, H.; Granger, D.; Parkin, S.;
Russell, T. P.; Anthony, J. E.; Brédas, J.-L.; Coropceanu, V.; Briseno, A. L. Bistetracene:
An Air-Stable, High-Mobility Organic Semiconductor with Extended Conjugation J. Am.
Chem. Soc. 2014, 136, 9248–9251. (b) Takimiya, K.; Shinamura, S.; Osaka, I.; Miyazaki,
E. Thienoacene-Based Organic Semiconductors Adv. Mater. 2011, 23, 4347–4370. (c)
Amaya, T.; Seki, S.; Moriuchi, T.; Nakamoto, K.; Nakata, T.; Sakane, H.; Saeki, A.;
Tagawa, S.; Hirao, T. Anisotropic Electron Transport Properties in Sumanene Crystal J.
Am. Chem. Soc. 2009, 131, 408–409. (d) Babudri, F.; Farinola, G. M.; Naso, F.; Ragni, R.
Fluorinated organic materials for electronic and optoelectronic applications: the role of the
fluorine atom Chem. Commun. 2007, 0, 1003–1022. (e) Allard, S.; Forster, M.; Souharce,
B.; Thiem, H.; Scherf, U. Organic Semiconductors for Solution‐Processable Field‐Effect
Transistors (OFETs) Angew. Chem., Int.-Ed. 2008, 47, 4070–4098. (f) Watanabe, M.;
Chang, Y. J.; Liu, S.-W.; Chao, T.-H.; Goto, K.; Islam, M. M.; Yuan, C.-H.; Tao, Y.-T.;
Shinmyozu, T.; Chow, T. J. The synthesis, crystal structure and charge-transport
properties of hexacene Nature Chem. 2012, 4, 574–578.
24
ACS Paragon Plus Environment

Page 25 of 27
The Journal of Organic Chemistry
7. Xiao, S.; Myers, M.; Miao, Q.; Sanaur, S.; Pang, K.; Steigerwald, M. L.; Nuckolls, C.
1
2
3
Molecular Wires from Contorted Aromatic Compounds
Angew. Chem., Int.-Ed. 2005,
4
5
6
117, 7556–7560.
7
8
9
8. (a) Pola, S.; Kuo, C.-H.; Peng, W.-T.; Islam, M. M.; Chao, I.; Tao, Y.-T. Contorted
Tetrabenzocoronene Derivatives for Single Crystal Field Effect Transistors: Correlation
between Packing and Mobility Chem. Mater. 2012, 24, 2566–2571. (b) Kumar, S.; Ho, M.-
T.; Tao, Y.-T. Unsymmetrically Extended Polyfused Aromatics Embedding Coronene and
Perylene Frameworks: Syntheses and Properties Org. Lett. 2016, 18, 200–203. (c) Kuo, C.-
H.; Huang, D.-C.; Peng, W.-T.; Goto, K.; Chao, I.; Tao, Y.-T. Substituent effect on the
crystal packing and electronic coupling of tetrabenzocoronenes: a structure–property
correlation J. Mater. Chem. C 2014, 2, 3928–3935. (d) Zhang, X.; Jiang, X.; Zhang, K.;
Mao, L.; Luo, J.; Chi, C.; Sze On Chan, H.; Wu, J. Synthesis, Self-Assembly, and Charge
Transporting Property of Contorted Tetrabenzocoronenes J. Org. Chem. 2010, 75, 8069–
8077.
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
9. Gorodetsky, A. A.; Chiu, C.-Y.; Schiros, T.; Palma, M.; Cox, M.; Jia, Z.; Sattler, W.;
Kymissis, I.; Steigerwald, M.; Nuckolls, C. Reticulated Heterojunctions for Photovoltaic
Devices Angew. Chem., Int.-Ed. 2010, 49, 7909–7912.
10. Liu, L.; Yang, B.; Katz, T. J.; Poindexter, M. K.Improved methodology for photocyclization
reactions J. Org. Chem. 1991, 56, 3769–3775.
11. (a) Sarhan, A. A. O.; Bolm, C. Iron(III) chloride in oxidative C–C coupling reactions Chem.
Soc. Rev. 2009, 38, 2730–2744. (b) Zhang, S.-L.; Xue, Z.-F.; Gao, Y.-R.; Mao, S.; Wang,
Y.-Q. Triple condensation of aryl methyl ketones catalyzed by amine and trifluoroacetic
acid: straightforward access to 1,3,5-triarylbenzenes under mild conditions Tetrahedron
Lett. 2012, 53, 2436 – 2439.
25
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 26 of 27
12. (a) Kumar, S.; Tao, Y.-T. Contorted Naphtho- and Fluorenocoronenes: Syntheses and
Properties of Polycyclic Aromatics beyond Benzo- and Thiophenocoronenes, Org. Lett.
2018, 20, 2320−2323. (b) Zhai, L.; Shukla, R.; Wadumethrige, S.; Rathore, R. Probing the
Arenium-Ion (ProtonTransfer) versus the Cation-Radical (Electron Transfer) Mechanism of
Scholl Reaction Using DDQ as Oxidant J. Org. Chem. 2010, 75, 4748−4760.
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
13. (a) Zhai, L.; Shukla, R.; Wadumethrige, S.; Rathore, R. Probing the Arenium-Ion
(ProtonTransfer) versus the Cation-Radical (Electron Transfer) Mechanism of Scholl Reaction
Using DDQ as Oxidant J. Org. Chem. 2010, 75, 4748−4760. (b) Rempala, P.; Kroulík, J.; King,
B. T. Investigation of the Mechanism of the Intramolecular Scholl Reaction of Contiguous
Phenylbenzenes J. Org. Chem. 2006, 71, 5067−5081. (c) Costa, P.; Trosien, I.;
Fernandez‐Oliva, M.; Sanchez‐Garcia, E.; Sander, W. Titlebild: The Fluorenyl cation Angew.
Chem. 2015, 127, 2593−2593. (d) Grzybowski, M.; Skonieczny, K.; Butenschön, H.; Gryko,
D. T. Comparison of oxidative aromatic coupling and the Scholl reaction Angew. Chem., Int.
Ed. 2013, 52, 9900−9930.
14. (a) Mahns, B.; Kataeva, O.; Islamov, D.; Hampel, S.; Steckel, F.; Hess, C.; Knupfer, M.;
Büchner, B.; Himcinschi, C.; Hahn, T.; Renger, R.; Kortus, J. Crystal Growth, Structure,
and Transport Properties of the Charge-Transfer Salt Picene 2,3,5,6-Tetrafluoro-7,7,8,8-
tetracyanoquinodimethane Cryst. Growth Des. 2014, 14, 1338–1346. (b) Yang, J.; Fang, H.-
H.; Ding, R.; Lu, S.-Y.; Zhang, Y.-L.; Chen, Q.-D.; Sun, H.-B. High-Quality Large-Size
Organic Crystals Prepared by Improved Physical Vapor Growth Technique and Their
Optical Gain Properties J. Phys. Chem. C 2011, 115, 9171–9175.
15. Huang, D.-C.; Kuo, C.-H.; Ho, M.-T.; Lin, B.-C.; Peng, W.-T.; Chao, I.; Hsu, C.-P.; Tao,
Y.-T. Contorted tetrabenzoacenes of varied conjugation: charge transport study with single-
crystal field-effect transistors J. Mater. Chem. C 2017, 5, 7935–7943.
16. Price, S. L.; Stone, A. J.; Lucas, J.; Rowland, R. S.; Thornley, A.E. The Nature of -
Cl···Cl- Intermolecular Interactions. J. Am. Chem. Soc. 1994, 116, 4910−4918.
26
ACS Paragon Plus Environment

Page 27 of 27
The Journal of Organic Chemistry
17. Desiraju, G. R.; Gavezzotti, A. From Molecular to Crystal Structure; Polynuclear
Aromatic Hydrocarbons. J. Chem. Soc., Chem. Commun. 1989, 621−623.
1
2
3
4
5
6
7
8
9
18. (a) Hirayama, S.; Sakai, H.; Araki, Y.; Tanaka, M.; Imakawa, M.; Wada, T.; Takenobu,
T.; Hasobe, T. Systematic Control of the Excited‐State Dynamics and Carrier‐Transport
Properties of Functionalized Benzo[ghi]perylene and Coronene Derivatives Chem. - Eur.
J. 2014, 20, 9081− 9093. (b) J. W. Patterson, The Ultraviolet Absorption Spectra of
Coronene, J. Am. Chem. Soc., 1942, 64, 1485–1486.
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
19. (a) Más-Montoya, M.; Cerón-Carrasco, J. P.; Hamao, S.; Eguchi, R.; Kubozono, Y.;
Tárraga, A.; Curiel, D. Synthesis and characterization of carbazolo[2,1-a]carbazole in thin film
and single crystal field-effect transistors J. Mater. Chem. C 2017, 5, 7020–7027. (b) Herwig,
P. T.; Müllen, K. A Soluble Pentacene Precursor: Synthesis, Solid‐State Conversion into
Pentacene and Application in a Field‐Effect Transistor Adv. Mater. 1999, 11, 480–483.
20. Islam, M. M.; Pola, S.; Tao, Y. T. Effect of interfacial structure on the transistor properties:
probing the role of surface modification of gate dielectrics with self-assembled monolayer using
organic sing-crystal field-effect transistors ACS Appl. Mater. & Interf. 2011, 3, 2136-2141.
27
ACS Paragon Plus Environment