Synthesis, Structures, Resolution, and Chiroptical Properties of 1,16-Diaryl-Substituted Benzo[5]helicene Derivatives

Article abstract of DOI:10.1002/asia.201601305

An efficient route to the synthesis of benzo[5]helicene derivatives functionalized on the interior side of the helix was developed, and resulted in a series of 1,16-diaryl-substituted benzo[5]helicene derivatives starting from easily available 7-methoxytetralone. X-ray crystal structures showed that the benzo[5]helicene derivatives had highly helical, twisted structures, and could all create hierarchical packing architectures with alternating P and M layers in the solid state. Moreover, seven pairs of enantiomers based on 1,16-diaryl-substituted benzo[5]helicene derivatives were also obtained by efficient resolution through HPLC with semipreparative chiral columns. The enantiomers all showed clear mirror-image circular dichroism (CD) spectra and high specific optical rotations, and their absolute configurations were determined by X-ray crystallography. Interestingly, a helical nanotubular structure was formed by the self-assembly of one enantiomer through halogen bonding. Furthermore, the enantiomers were found to have high racemization barriers and thermostability, which might be caused by the introduction of aryl substituents at the C1(C16) position.

Full text of DOI:10.1002/asia.201601305

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Accepted Article
Title: Synthesis, Structures, Resolution and Chiroptical Properties of 1,16-Diaryl
Substituted Benzo[5]helicene Derivatives
Authors: Chuan-Feng Chen; Wei-Bin Lin; Meng Li; Lei Fang; Yun Shen
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Chemistry - An Asian Journal
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Synthesis, Structures, Resolution and Chiroptical Properties of
1
,16-Diaryl Substituted Benzo[5]helicene Derivatives
[a],[b]
[a]
[a],[b]
[a]
[a],[b]
Wei-Bin Lin,
Meng Li, Lei Fang,
Yun Shen, and Chuan-Feng Chen*
Dedication ((optional))
[
10]
Abstract: An efficient route to the synthesis of benzo[5]helicene
derivatives functionalized on interior side of the helix was developed,
which resulted in a series of 1,16-diaryl substituted benzo[5]helicene
derivatives starting from the easily available 7-methoxy-tetralone. X-
ray crystal structures showed that the benzo[5]helicene derivatives
had highly helical twisted structures, and could all create hierarchical
packing architectures with alternating P-layer and M-layer in the
solid states. Moreover, seven pairs of enantiomers based on the
al.
reported that introduction of substituents into the interior
side of helix is an efficient way to improve the racemization
barrier of helicene. As result, it was found that the
racemization barrier of 1-methyl[5]helicene (ΔG = 38.6 kcal·mol ,
473 K) was even higher than that of [6]helicene (ΔG = 36.9
a
-1
-1
[11a]
kcal·mol , 469 K). Recently, we
also found that 1,16-
dimethylbenzo[5]helicenes did not undergo any racemization at
120 C even for long time. Despite rapid development of
helicenes in both synthesis and applications in recent years,
there are still few reports about the functionalization on the
positions near Fjord region of [5]helicenes for the great steric
1,16-diaryl substituted benzo[5]helicene derivatives were also
obtained by the efficient resolution through high performance liquid
chromatography (HPLC) with semi-preparative chiral columns. The
enantiomers all showed clear mirror image CD spectra and high
specific optical rotations, and their absolute configurations were
[
11,12]
hindrance (Figure 1).
To explore their practical applications
in chiral recognition, chiral assembly, and chiral organic
functional materials, undoubtedly, it is very important and
meaningful to develop new and efficient routes to functionalize
on the interior side of the helix and synthesize optically pure and
stable [5]helicene derivatives.
determined by X-ray crystal structure. Interestingly,
a helical
nanotubular structure was formed by the self-assembly of one
enantiomer via halogen bonding. Furthermore, the enantiomers were
found to have high racemization barrier and thermostability, which
might be caused by the introduction of aryl substituents at C1(C16)
position.
Introduction
From microscopic DNA to gigantic galaxies, helicity is prevailing
both in physical objects and artistic expression. When it comes
to the molecular world, the helicenes with aesthetic charm are
the perfect embodiment of helicity. Besides structural curiosity
and beauty, helicenes with the unique properties caused by their
helically extended chiral π-systems have attracted increasing
Figure 1. Fjord regions and numbering of [5]helicene and benzo[5]helicene.
Herein, we report a new and efficient route to the synthesis of
1,16-diaryl substituted benzo[5]helicene derivatives starting from
[1]
interests in recent years. Unique π-conjugated screw-shaped
the easily available 7-methoxy-tetralone. We also found that the
great induced torsional strain caused by the two aryl
substituents on the inter side of helix resulted in twister helical
structures, which could further make the helical molecules pack
into hierarchical stacking structures with alternating P-layer and
M-layer in the solid states. Moreover, we also obtained seven
pairs of optically pure enantiomers based on the 1,16-diaryl
substituted benzo[5]helicene derivatives by efficient resolution
through HPLC with semi-preparative chiral columns. These
enantiomers showed good mirror image of CD spectra and high
specific optical rotation, and their absolute configurations could
be determined by X-ray crystal structure. Interestingly, it was
further found that M-1f could self-assemble into a nanotubular
structure with a single helical chirality by halogen bondings.
Furthermore, the enantiomers based on the 1,16-
diarylbenzo[5]helicenes were also proved to have high
racemization barrier and thermostability.
[
2]
structures and specific chiroptical properties of the helicenes
endow them with wide potential applications in molecular
[3]
[4]
[5]
assemblies, functional materials, and asymmetric catalysis.
Moreover, the self-assemblies of helicenes in solution and solid
states have also been studied extensively for they displayed
[
3a,6]
intriguing properties, such as liquid crystallinity,
nonlinear
[7]
[8]
optical susceptibility, circularly polarized luminescence, and
[
3d]
semiconductivity.
Among the family of helicenes, [5]helicene is one of the most
important members as well as one of the easiest to synthesis,
[
1,9]
but it also takes place racemization easily.
In 1996, Borkent et
[
a]
b]
W.-B. Lin, Dr. M. Li, L. Fang, Dr. Y. Shen, Prof. C.-F. Chen
Beijing National Laboratory for Molecular Sciences
CAS Key Laboratory of Molecular Recognition and Function
Institute of Chemistry, Chinese Academy of Sciences
Beijing 100190, China.
E-mail: cchen@iccas.ac.cn
Results and Discussion
[
W.-B. Lin, L. Fang, Prof. C.-F. Chen
University of Chinese Academy of Sciences, Beijing 100049, China
Synthesis of 1,16-Diarylbenzo[5]helicene Derivatives
Synthesis of 1,16-diaryl substituted benzo[5]helicene derivatives
Supporting information for this article is given via a link at the end of
the document.((Please delete this text if not appropriate))
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was depicted in Scheme 1 and summarized in Table 1. Starting
from commercial material 2, compound 3 could be easily
brominated by N-bromosuccinimide (NBS) in the presence of
the product isolated after steps c and e.
Structures of 1,16-Diarylbenzo[5]helicene Derivatives
[
13]
To investigate the structural properties of the diaryl substituted
benzo[5]helicene derivatives and their self-assembling behaviors
in solid state, we obtained single crystals of racemic 1a, 1b and
3
FeCl . Treatment of 3 by the previous reported method gave 4,
which underwent Diels-Alder reaction with 2-carboxybenzene
diazonium chloride to form 5. Unfortunately, when 5 was
performed Suzuki coupling reactions via route 1, product 6 could
not be obtained, which might be because of the great steric
hindrance of the inner space of 5. Nonetheless, it was noted that
conformation of compound 4 was flexible and the steric
hindrance around two bromine atoms could be sharply
decreased compared to that of 5. Thus, we tried the Suzuki
coupling reactions of dibromide 4 and different arylboronic acid
1d-f suitable for X-ray diffraction analysis by vapor diffusion of n-
hexane into their solutions in dichloromethane or ethyl acetate.
As shown in Figure 2 and Figure 3, the benzo[5]helicene
skeletons all showed highly helical twisted structures. The
[14]
distortions of the diarylbenzo[5]helicene derivatives defined by
the sum of the three torsion angles of C1-C1d-C1c-C1b, C1d-
C1c-C1b-C1a, and C1c-C1b-C1a-C16 were ranging from 81.5°
to 88.3° (Table 2), which were all larger than 78.1° of the
2 3 2 2
in toluene/EtOH/H O (v/v/v, 2:2:1) with Pd(PPh ) Cl as the
[
1a,15]
[
5]helicene.
Moreover, the distances between the two
catalyst (route 2), and found that the reactions could proceed
smoothly to give the diaryl substituted products 7a-g in 42-91%
yield. Finally, by Diels-Alder reaction between 7a-g and 2-
carboxybenzene diazonium chloride in 1,2-dichloroethane and
oxygen atoms of methoxyl groups were all farther than 4.80 Å of
their benzo[5]helicene analogues with no substituents on C1 and
[
16]
C16 positions. Increase of the distortions and the distances of
oxygen atoms should be mainly attributed to the steric repulsion
between the two aryl groups. It was also found that the average
bond lengths of the C-C bonds in the inner helix were about
2-methyloxirane, and subsequently oxidative dearomatization of
6
with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), the
target benzo[5]helicene derivatives rac-1a-g with different aryl
substituents at C1 and C16 positions were obtained in 60-90%
yield for the two steps.
1
.44(7)-1.45(0) Å, which were obviously bigger than that of
[
1a,17]
benzene ring of 1.39(3) Å.
These results indicated that aryl
substituents introduced in the fjord region of the terminal rings
made the benzo[5]helicene derivatives undergo a more twisted
structure to minimize steric interaction and sharply increased
torsional strain.
Table 2. Summary of crystal data of the racemic benzo[5]helicene derivatives
[
a]
[b]
Substrate
rac-1a
rac-1b
rac-1d
rac-1e
rac-1f
Distortion
81.6
Average of inner C-C
1.44(8)
d(O-O)
5.14
5.20
5.24
5.04
5.22
82.3
1.44(7)
85.7
1.44(9)
Scheme 1. Synthesis of 1,16-diaryl substituted benzo[5]helicene derivatives.
81.5
1.45(0)
Reagents and conditions: a) NBS, FeCl
3
, MeCN, r.t., 8h; b) Zn, TMSCl, conc.
88.3
1.45(0)
HCl, THF, -78℃ to r.t., 3h; c) 2-carboxybenzene diazonium chloride, 2-
methyloxirane, 1,2-dichloroethane, reflux, 6h; d) arylboronic acid, Pd(PPh
CO , toluene/EtOH/H
2h.
3
2 2
) Cl ,
[
a] The average of C-C bonds at inner helix. [b] The distance of the two
K
2
3
2
O (v/v/v, 2:2:1), 80℃, 12h; e) DDQ, xylene, reflux,
oxygen atoms of methoxyl groups.
1
Table 1. Synthesis of rac-1a-f and their precursors 7a-f
Self-assembling behaviors of these racemic benzo[5]helicene
derivatives were further investigated. It was found that racemic
diarylbenzo[5]helicene derivatives 1a, 1b and 1e showed similar
columnar packing structures of heterochiral crystals. Each
column was formed from a single enantiomer with a staggered
packing pattern, resulting in alternating right-handed (P-helical,
shown in red) and left-handed (M-helical, shown in blue)
configurations (Figures 2b, 2d and 2f). Moreover, it was also
found that the array of columns of same chirality constituted a
chiral layer, and neighboring layers showed opposite chirality,
which thus formed unique hierarchical packing structures with
self-sorting of the chirality. The molecules of rac-1a, rac-1b or
rac-1e in the same column were stacked by C-H···π interactions
with the distances of 2.86, 2.68-2.87 or 2.57-2.90 Å, respectively.
[
a]
[b]
Entry
Ar
Product
7a
Yield
Product Yield
1
2
3
4
5
6
7
4-trifluoromethylphenyl
4-fluorophenyl
42
rac-1a
rac-1b
rac-1c
rac-1d
rac-1e
rac-1f
rac-1g
70
68
90
65
62
71
60
7b
65
phenyl
7c
70
4-methylphenyl
4-methoxyphenyl
4-chlorophenyl
4-(diphenylamino)phenyl
7d
67
7e
71
7f
74
7g
91
[
a] Yield (%) of the product isolated after step d in route 2. [b] Yield (%) of
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There also existed a π···π stacking interaction between adjacent
molecules in the columns of rac-1b with the distance of 3.37 Å,
which was uncommon in the assembled structures with one-
dimensional columnar helicene packing.
Figure 3. (a) ORTEP drawing and (b, c) packing structure of rac-1d. (d)
ORTEP drawing (e, f) packing structure of rac-1f. The P enantiomer is shown
in red and the M enantiomer in blue. Hydrogen atoms have been omitted for
clarity.
Resolution of 1,16-Diarylbenzo[5]helicene Derivatives and
Chiroptical Properties of the Enantiomers
To study chiroptical properties of these 1,16-diaryl substituted
benzo[5]helicene derivatives, their enantiomeric resolutions
were then achieved by HPLC with semi-preparative chiral
columns and n-hexane-dichloromethane as the mobile phase
(
see Supporting Information for details) to give seven pairs of
optically pure enantiomers. The CD spectra of each pair of the
enantiomers exhibited clear mirror images in dichloromethane
Figure 2. (a) ORTEP drawing and (b) packing structure of rac-1a. (c) ORTEP
drawing and (d) packing structure of rac-1b. (e) ORTEP drawing and (f)
packing structure of rac-1e. The P enantiomer is shown in red and the M
enantiomer in blue. Hydrogen atoms and solvent molecules have been omitted
for clarity.
(
see Figure 5 and Figures S51-56), in which the enantiomers
with longer retention time were shown in black solid lines while
the enantiomers with longer retention time were shown in dash
lines. It was also found that the enantiomers based on 1,16-
diaryl substituted benzo[5]helicene derivatives 1b-f displayed
similar CD spectra in the range of 250-450 nm (Figure 5a,
Figure S51-S56). Compared with 1b-f, the spectra of the
enantiomers of 1a showed positive rather than negative signal at
near 250 nm, while the signal at around 320 nm exhibited a
slight red-shift (Figure S51 and S56), which might be due to the
strong electron-accepting 4-trifluoromethyl phenyl groups. For
the enantiomers of 1g containing strong electron-accepting
groups, four major peaks with obviously red-shifts compared
with the others were found in the CD spectra (Figure 5b).
In the cases of rac-1d and rac-1f, their assemblies seemed to
be different from those of rac-1a, rac-1b and rac-1e. As shown
in Figure 3, no obvious one-dimensional columnar alignments of
heterochiral crystal were observed; but braid-like layer structures
viewed along a certain axis were unexpectedly displayed (Figure
3b, 3e). For rac-1f, Z- or ladder-like packing slices of hierarchical
structures (Figure 3f) formed by the C-H···Cl (2.87 Å) and C-
H···π (2.88 Å) interactions were shown, while rac-1d exhibited a
similar ladder-like packing slices of heterochiral crystal (Figure
The CD spectra could also be used to assign the absolute
configuration of the helicenes by comparison with those of the
3c). If it was viewed from the dashed lines as depicted in Figures
3b-f, both rac-1d and rac-1f exhibited hierarchiral packing
[
18]
known [5]helicenes,
in which the negative Cotton effect (or
structures with alternating P-layer and M-layer to some extent.
positive Cotton effect) at the maximum absorption peak was
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[
1a]
always observed for P (or M) helicenes. Thus, by virtue of the
Cotton effect around 424 nm, the absolute configurations of the
enantiomers with shorter retention times could be assigned as P
configurations, while the enantiomers with longer retention times
were assigned as M configurations. Specific optical rotations of
the enantiomers of the benzo[5]helicene derivatives were further
measured in dichloromethane (Supporting Information, Table
S2). It was found that the enantiomers all showed high specific
optical rotations above ±1100° except that of 1g with two flexible
electron-donating substituents. Moreover, the enantiomers with
positive specific optical rotations could be determined to be P
configuration, while the enantiomers with negative specific
optical rotations were M configurations, which were also in
accordance with the results speculated by CD spectra.
Interestingly, it was also found that unlike columnar stacking of
the stair-like packing slices of the heterochiral crystal of rac-1f,
enantiomer (-)-M-1f performed a unique homochiral assembly of
laevorotatory helix to form a helical nanotubular structure by
halogen bonding interactions of C-Cl···Cl (3.37 Å, 145.0°) and
C-Cl···π (3.45 Å, 140.4°) between the adjacent homochiral
[
19]
molecules (Figures 6b, d and e).
The adjacent helixes were
mainly interconnected by C-H···π (2.85 Å, 2.89 Å) interactions.
To our knowledge, this is the first example of one dimensional
helical nanotube self-assembled by homochiral helicenes via
[
19a]
halogen bonding interactions.
60
40
20
0
(+)- P -1f
-)- M -1f
(
-
-
-
20
40
60
250
300
350
400
450
500
Wavelength / nm
6
4
2
0
(
(
+)- P -1g
-)- M -1g
0
0
0
-
20
40
60
Figure 6. (a) ORTEP drawing, (b) halogen bonding interactions, (c) crystal
cell, (d) top view and (e) side view of packing structure of M-1f. Hydrogen
atoms in a-c have been omitted for clarity.
-
-
2
50
300
350
400
450
500
Since the racemization barrier of simple [5]helicene can be
significantly improved by the introduction of substituents, even
the methyl group(s), into the interior side of helix, it could be
reasonably expected that the enantiomers based on the
benzo[5]helicene derivatives with two aryl groups at C1 and C16
positions should have higher racemization barriers and better
Wavelength / nm
[
1a]
Figure 5. CD spectra (0.1 mM, CH
g and (-)-M-1g.
2 2
Cl , 25 °C) of (+)-P-1f and (-)-M-1f, (+)-P-
1
To determine the absolute configurations of the enantiomers,
thermal stabilities than even those of [7]helicenes and 1,16-
we also obtained the single crystal of enantiomer 1f with longer
retention time by vapor diffusion of n-hexane into its solution in
dichloromethane. By the general principle that laevorotatory (or
dextrorotatory) carbohelicenes has M helicity (or P helicity), it
was unambiguously to assign the absolute configuration of the
enantiomer as M-1f (Figure 6a). We further investigated the self-
assembled behaviors of enantiomer M-1f in solid state. As
shown in Figure 6c, the crystal cell was found to have an
extraordinary long axis, with a length of about 68.81 Å.
[11a]
dimethyl substituted benzo[5]helicenes.
Therefore, we further
tried to explore the racemization barrier of M-1c containing two
phenyl groups by HPLC with analytical chiral column. When M-
1c was dissolved in diethylene glycol dibutyl ether, heated to
200C, and then detected by HPLC once an hour. No obvious
changes of the HPLC spectra were observed after 10 hours
See Figure S50), which implied that, as expected, enantiomer
(
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M-1c exhibited high racemization barrier and excellent
thermostability.
under argon atmosphere, cooled to room temperature, and then added
ethyl acetate (50 mL) and water (50 mL). The organic layer was washed
with water twice more (2×50 mL), dried over anhydrous MgSO , and then
4
concentrated in vacuo. The residue was subjected to silica gel column
chromatography to afford the pure product 7.
Conclusions
1
Compound 7a: Yellow power (42%); M.p.: 223-224 C; H NMR (CDCl
3
,
5
00 MHz): δ = 7.30 (d, J = 7.4 Hz, 2H), 7.19 (d, J = 7.5 Hz, 2H), 6.88 (d,
We have developed an efficient route for the convenient
synthesis of 1,16-diaryl substituted benzo[5]helicene derivatives
starting from the easily available material, and obtained a series
of racemic 1,16-diaryl substituted benzo[5]helicene derivatives in
considerable yields. The X-ray crystal structures revealed that
the helical scaffolds of the benzo[5]helicene derivatives were all
significantly twisted with a distortion ranges of 81.5-88.3°, which
might be influenced by different aryl substituents at C1(C16)
position. Particularly, it was found that the racemic helicene
derivatives 1a, 1b, 1d, 1e and 1f exhibited special hierarchical
packing structures with alternating P-layer and M-layer, which
could mainly be attributed to the effect on the structures of aryl
substituents at C1(C16) position. Moreover, seven pairs of
optically pure enantiomers of 1,16-diarylbenzo[5]helicenes were
also obtained by efficient resolution through HPLC with semi-
preparative chiral columns. As expected, the enantiomers all
showed clear mirror image CD spectra and high specific optical
rotations, and their absolute configurations could be determined
by X-ray crystal structure. Interestingly, we further found that
enantiomer (-)-M-1f could self-assemble into helical nanotubular
structure of homochiral crystal by halogen bonding interactions.
Furthermore, HPLC was performed to explore racemization of
the enantionmer, which expectedly proved the high racemization
barrier and pronounced thermostability. The results presented
here provided us an efficient synthetic route to 1,16-diaryl
substituted benzo[5]helicene derivatives. We also believe that
these optically pure and stable benzo[5]helicene derivatives
functionalized on the interior side of the helix could find wide
potential applications in the chiral recognition, chiral assembling,
and even in the construction of chiral organic functional
materials.
J = 7.5 Hz, 2H), 6.85 (d, J = 8.2 Hz, 2H), 6.66 (d, J = 8.2 Hz, 2H), 6.51 (d,
J = 7.6 Hz, 2H), 6.12–6.04 (m, 2H), 3.50 (s, 6H), 2.13 (d, J = 14.7 Hz,
13
2
1
1
3
H), 1.99–1.84 (m, 4H), 1.20 (d, J = 9.3 Hz, 2H) ppm; C NMR (CDCl ,
25 MHz): δ = 154.9, 140.8, 140.4, 133.9, 133.5, 132.9, 131.9, 131.8,
28.5, 128.3, 128.0, 127.6, 127.5, 125.7, 123.5, 123.0, 122.5, 109.4,
+
56.1, 27.6, 22.6 ppm; HR MS (ACPI): m/z 607.2066 [M+H] ; found:
607.2051.
1
Compound 7b: White solid (65%); M.p.: 210-211 C; H NMR (CDCl
500 MHz): δ = 6.84 (d, J = 8.2 Hz, 2H), 6.71 (s, 6H), 6.63 (d, J = 8.2 Hz,
3
,
2H), 6.33 (s, 2H), 6.05 (t, J = 5.4 Hz, 2H), 3.49 (s, 6H), 2.19 (d, J = 14.8
13
Hz, 2H), 1.93 (dd, J = 12.5, 6.0 Hz, 4H), 1.43 (m, 2H) ppm; C NMR
CDCl , 125 MHz): δ = 162.8, 160.9, 155.1, 141.2, 134.3, 134.1, 133.8,
33.3, 132.49, 132.47, 131.0, 127.9, 126.9, 126.8, 113.0, 112.8, 112.7,
12.5, 109.4, 56.1, 28.2, 22.7 ppm; HR MS (ACPI): m/z 507.2130
(
1
1
3
+
[M+H] ; found: 507.2121.
1
Compound 7c: Yellow power (70%); M.p.: 120-121 C; H NMR (CDCl
500 MHz): δ = 7.16 (t, J = 7.4 Hz, 2H), 7.00 (s, 4H), 6.80 (d, J = 8.2 Hz,
2H), 6.77 (s, 2H), 6.63 (d, J = 8.2 Hz, 2H), 6.40 (s, 2H), 6.05–5.95 (m,
3
,
13
2
(
1
H), 3.47 (s, 6H), 2.04 (s, 2H), 1.88 (s, 4H), 1.29 (s, 2H) ppm; C NMR
CDCl , 125 MHz): δ = 155.0, 141.4, 136.8, 134.4, 133.7, 133.0, 131.9,
30.8, 129.1, 126.5, 126.2, 125.9, 125.7, 109.4, 56.2, 28.2, 22.8 ppm;
3
+
HR MS (ACPI): m/z 471.2319 [M+H] ; found: 471.2309.
1
3
Compound 7d: Yellow power (67 %); M.p.: 256-257 C; H NMR (CDCl ,
500 MHz): δ = 6.78 (d, J = 8.0 Hz, 8H), 6.61 (d, J = 8.1 Hz, 4H), 6.28 (s,
2H), 5.99 (t, J = 5.2 Hz, 2H), 3.48 (s, 6H), 2.33 (s, 6H), 2.08 (s, 2H), 1.88
13
3
(s, 4H), 1.32 (s, 2H) ppm; C NMR (CDCl , 125 MHz): δ = 155.1, 141.6,
135.5, 134.3, 134.0, 133.7, 132.9, 131.6, 130.5, 129.0, 126.7, 126.2,
109.1, 56.2, 28.0, 22.8, 21.3 ppm; HR MS (ACPI): m/z 499.2632 [M+H] ;
found: 499.2628.
+
1
Compound 7e: White solid (71 %); M.p.: 250-251 C; H NMR (CDCl
3
,
5
00 MHz): δ = 6.80 (d, J = 8.1 Hz, 2H), 6.67 (d, J = 9.8 Hz, 2H), 6.61 (d,
J = 8.2 Hz, 2H), 6.56 (s, 4H), 6.31 (s, 2H), 6.02 (t, J = 5.4 Hz, 2H), 3.81
s, 6H), 3.49 (s, 6H), 2.13 (d, J = 12.1 Hz, 2H), 1.91 (s, 4H), 1.44 (s, 2H)
(
13
ppm; C NMR (CDCl
3
, 125 MHz): δ = 158.2, 155.2, 141.6, 134.3, 134.0,
1
32.7, 130.4, 129.2, 128.6, 126.2, 111.5, 109.2, 56.2, 55.3, 28.4, 22.8
+
ppm; HR MS (ACPI): m/z 531.2530 [M+H] ; found: 531.2522.
Experimental Section
1
Compound 7f: Yellow power (74 %); M.p.: 269-270 C; H NMR (CDCl
3
,
5
00 MHz): δ = 7.00 (d, J = 7.7 Hz, 2H), 6.92 (d, J = 7.8 Hz, 2H), 6.86 (d,
All reactions were carried out under argon using oven-dried glassware.
Flash column chromatography was performed on 100-200 mesh silica
gel. Melting points, taken on an electrothermal melting point apparatus,
J = 8.2 Hz, 2H), 6.69 (d, J = 7.7 Hz, 2H), 6.63 (d, J = 8.2 Hz, 2H), 6.30 (d,
J = 8.0 Hz, 2H), 6.06 (t, J = 5.4 Hz, 2H), 3.49 (s, 6H), 2.21 (d, J = 14.2 Hz,
2H), 2.01 – 1.87 (m, 4H), 1.43 (s, 2H) ppm; C NMR (CDCl
13
1
13
3
, 125 MHz):
were uncorrected. H and C NMR spectra were recorded on Bruker AV
500 MHz spectrometers. High-resolution mass spectra (HRMS) were
δ = 154.9, 141.1, 135.0, 134.2, 134.1, 133.7, 133.0, 132.2, 131.3, 127.7,
Ⅲ
127.0, 126.2, 125.9, 109.4, 56.1, 27.8, 22.7 ppm; HR MS (ACPI): m/z
measured in the APCI mode. X-ray crystallographic data were collected
by Rigaku Saturn 724 with graphite-monochromated Mo-Kα radiation.
Specific rotation was obtained on a Rudolph Autopol VI Automatic
+
539.1539 [M+H] ; found: 539.1228.
1
Compound 7g: Yellow power (91 %); M.p.: 200-201 C; H NMR (CDCl
3
,
polarimeter. CD spectra were obtained on
a
Jasco-810
500 MHz): δ = 7.28 (d, J = 7.6 Hz, 6H), 7.16 (d, J = 8.0 Hz, 8H), 7.03 (t, J
= 7.3 Hz, 5H), 6.80 (d, J = 8.1 Hz, 2H), 6.72 (d, J = 8.3 Hz, 4H), 6.63 (s,
2H), 6.58 (d, J = 8.1 Hz, 2H), 6.27 (s, 2H), 6.05 (t, J = 5.2 Hz, 2H), 3.45
spectropolarimeter. HPLC was performed by Agilent Technologies1260
infinite. Commercial reagents were used without further purification.
Anhydrous solvents were dried from 4 Å molecular sieves.
13
3
(s, 6H), 2.28 (s, 2H), 1.99 (s, 4H), 1.77 (s, 2H) ppm; C NMR (CDCl ,
1
1
25 MHz): δ = 155.2, 147.9, 145.7, 141.5, 134.3, 133.8, 132.5, 130.6,
30.0, 129.1, 128.93, 128.88, 126.0, 124.8, 124.5, 124.4, 122.8, 120.1,
General Procedure for the Suzuki-Miyaura Cross-Coupling
+
A mixture of the bromide 4 (4 mmol), boronic acid (10 mmol), and K
40 mmol) dissolved in toluene (80 mL), EtOH (80 mL) and water (40 mL)
under argon atmosphere was added catalytic amount of Pd(PPh Cl
around 10% mol). The resulting mixture was stirred for 12 hours at 80 C
2
CO
3
110.0, 56.4, 29.1, 22.8 ppm; HR MS (ACPI): m/z 805.3789 [M+H] ;
found: 805.3772.
(
3
)
2
2
General Procedure for the Diels-Alder Addition and Oxidative
Dearomatization
(
This article is protected by copyright. All rights reserved

Chemistry - An Asian Journal
10.1002/asia.201601305
FULL PAPER
1
A solution of diene 2 (2 mmol) and 2-carboxybenzenediazonium chloride
Compound rac-1g: Yellow power (60%); M.p.: 173-174 C; H NMR
(4 mmol) in 1,2-dichloroethane (20 mL) and propylene oxide (4 mL) was
3
(CDCl , 500 MHz): δ = 8.65 (dd, J = 6.3, 3.4 Hz, 2H), 8.36 (d, J = 8.7 Hz,
refluxed for 6 h. Then, the reaction mixture was concentrated under
reduced pressure and subjected to flash column chromatography. After
rotatory evaporation, the crude was dissolved in anhydrous xylene (50
mL), and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ, 15 mmol) was
added. The mixture was refluxing with vigorous stirring overnight. After
the reaction was cooled to room temperature, the solution was subjected
to a column chromatography to afford product rac-1.
2H), 7.69 (d, J = 8.6 Hz, 2H), 7.67 (dd, J = 6.3, 3.2 Hz, 2H), 7.63 (d, J =
8.8 Hz, 2H), 7.31–7.26 (m, 8H), 7.20 (d, J = 8.8 Hz, 2H), 7.09 (d, J = 7.6
Hz, 8H), 7.01 (t, J = 7.3 Hz, 4H), 6.59 (dd, J = 8.4, 2.1 Hz, 2H), 6.51 (dd,
J = 8.4, 2.4 Hz, 2H), 6.08 (dd, J = 8.4, 2.4 Hz, 2H), 5.31 (dd, J = 8.4, 2.1
13
3
Hz, 2H), 3.66 (s, 6H) ppm; C NMR (CDCl , 125 MHz): δ = 155.7, 147.8,
144.0, 131.3, 131.1, 130.2, 129.9, 129.20, 129.17, 128.9, 128.6, 127.3,
126.7, 126.5, 126.4, 124.1, 123.4, 122.3, 121.7, 121.3, 117.0, 114.0,
+
1
57.2 ppm; HR MS (ACPI): m/z 875.3632 [M+H] ; found: 875.3630.
Compound rac-1a: Yellow power (70%); M.p.: 220-221 C; H NMR
(
CDCl
3
, 500 MHz): δ = 8.66 (dt, J = 6.3, 3.4 Hz, 2H), 8.30 (d, J = 8.6 Hz,
H), 7.71 (dt, J = 6.3, 3.4 Hz, 2H), 7.62 (d, J = 8.8 Hz, 2H), 7.46 (d, J =
.6 Hz, 2H), 7.25 (s, 2H), 7.04 (dd, J = 8.2, 2.0 Hz, 2H), 6.92–6.82 (m,
X-Ray Crystallography
2
8
2
CCDC 1500424 (rac-1a), CCDC 1500423 (rac-1b), CCDC 1500426 (rac-
1d), CCDC 1500429 (rac-1e), CCDC 1500430 (rac-1f), and CCDC
13
H), 6.58–6.47 (m, 2H), 5.52 (d, J = 8.0 Hz, 2H), 3.69 (s, 6H) ppm;
, 125 MHz): δ = 155.4, 139.9, 130.9, 130.21, 130.19, 129.0,
28.8, 128.4, 127.8, 127.3, 127.1, 126.2, 125.9, 125.6, 125.1, 124.6,
23.5, 123.4, 122.8, 122.7, 122.43, 122.40, 117.1, 112.7, 57.0 ppm; HR
C
1501288 (M-1f) contain the supplementary crystallographic data for this
NMR (CDCl
1
1
3
paper. These data are provided free of charge by The Cambridge
Crystallographic Data Centre These data can be obtained free of charge
from
www.ccdc.cam.ac.uk/data request/cif.
Crystal data for rac-1a: C42
crystal size 0.31 x 0.24 x 0.22 mm , monoclinic, space group P2(1)/n, a =
The
Cambridge
Crystallographic
Data
Centre
via
+
MS (ACPI): m/z 677.1910 [M+H] ; found: 677.1910.
Compound rac-1b: Yellow power (68%); M.p.: 143-144 C; H NMR
CDCl , 500 MHz): δ = 8.65 (dd, J = 6.2, 3.4 Hz, 2H), 8.29 (d, J = 8.7 Hz,
H), 7.70 (dd, J = 6.3, 3.2 Hz, 2H), 7.66 (d, J = 8.8 Hz, 2H), 7.54 (d, J =
.6 Hz, 2H), 7.24 (d, J = 8.8 Hz, 2H), 6.68 (m, 2H), 6.48 (td, J = 8.8, 2.8
1
26 6 2
H F O , CCDC 1500424, Mw = 676.63,
(
2
8
3
3
2
0.314(4) Å, b = 13.359(3) Å, c = 25.999(5) Å, α = 90°, β = 98.97(3)°, γ =
3
–3
90°, V = 6969(2) Å , Z = 8, Dc = 1.290 Mg m , T = 173(2) K, μ = 0.100
Hz, 2H), 5.99 (td, J = 8.8, 2.8 Hz, 2H), 5.38 (m, 2H), 3.67 (s, 6H) ppm;
–1
mm , 47091 reflections measured, 15904 unique (Rint = 0.0661), final R
indices [I2σ(I)]: R = 0.1127, wR = 0.2605, R indices (all data): R
.1336, wR = 0.2750.
Crystal data for rac-1b: C40
crystal size 0.41 x 0.31 x 0.06 mm , triclinic, space group P , a =
1
3
3
C NMR (CDCl , 125 MHz): δ = 161.1, 159.2, 155.4, 132.2, 130.8, 130.2,
1
2
1
=
1
1
30.13, 130.07, 129.93, 129.0, 128.9, 128.74, 128.73, 127.4, 126.9,
25.5, 125.2, 123.5, 117.1, 113.0, 112.9, 112.8, 112.6, 112.5, 57.0 ppm;
0
2
+
26 2 2
H F O , CCDC 1500423, Mw = 636.05,
HR MS (ACPI): m/z 577.1974 [M+H] ; found: 577.1973.
3
̅
1
Compound rac-1c: Yellow power (90%); M.p.: 147-148 C; H NMR
CDCl , 500 MHz): δ = 8.65 (d, J = 9.6 Hz, 2H), 8.24 (d, J = 8.7 Hz, 2H),
.68 (dd, J = 6.3, 3.2 Hz, 2H), 7.57 (d, J = 8.8 Hz, 2H), 7.41 (d, J = 8.6
Hz, 2H), 7.24 (d, J = 8.8 Hz, 2H), 6.83–6.77 (m, 2H), 6.76–6.68 (m, 4H),
1
8
=
1.4303(17) Å, b = 13.8758(19) Å, c = 20.236(3) Å, α = 82.586(6)°, β =
1.907(6)°, γ = 75.958(5)°, V = 3067.6(8) Å , Z = 4, Dc = 1.377 Mg m , T
173(2) K, μ = 0.209 mm , 40196 reflections measured, 14021 unique
(
7
3
3
–3
–1
(
R
int = 0.0430), final R indices [I2σ(I)]: R
indices (all data): R = 0.0936, wR = 0.1942.
Crystal data for rac-1d: C42 , CCDC 1500426, Mw = 568.67, crystal
size 0.203 x 0.152 x 0.07 mm , monoclinic, space group I2(1)/a, a =
1 2
= 0.0831, wR = 0.1867, R
13
6
.33–6.25 (m, 2H), 5.41 (d, J = 7.8 Hz, 2H), 3.66 (s, 6H) ppm; C NMR
1
2
(CDCl , 125 MHz): δ = 155.4, 136.4, 130.7, 130.2, 129.9, 128.89, 128.86,
3
32 2
H O
1
1
5
28.4, 127.8, 127.6, 126.6, 126.5, 126.2, 126.1, 125.5, 124.4, 123.4,
16.6, 113.1, 57.1 ppm; HR MS (ACPI): m/z 541.2162 [M+H] ; found:
41.2154.
3
+
1
=
0
2.394(3) Å, b = 16.481(3) Å, c = 14.814(7) Å, α = 90°, β = 107.79(3)°, γ
3
–3
90°, V = 2881.3(17) Å , Z = 4, Dc = 1.311 Mg m , T = 173(2) K, μ =
1
Compound rac-1d: Yellow power (65%); M.p.: 258-259 C; H NMR
–1
.079 mm , 17437 reflections measured, 3281 unique (Rint = 0.0620),
(CDCl
3
, 500 MHz): δ = 8.64 (dd, J = 6.3, 3.4 Hz, 2H), 8.23 (d, J = 8.7 Hz,
H), 7.67 (dd, J = 6.3, 3.2 Hz, 2H), 7.56 (d, J = 8.8 Hz, 2H), 7.43 (d, J =
.6 Hz, 2H), 7.21 (d, J = 8.8 Hz, 2H), 6.66–6.51 (m, 4H), 6.07 (d, J = 7.8
final R indices [I2σ(I)]: R
0.0642, wR = 0.1389.
Crystal data for rac-1e: C42
size 0.29 x 0.24 x 0.11 mm , monoclinic, space group P2(1)/c, a =
1.856(3) Å, b = 13.319(3) Å, c = 19.610(5) Å, α = 90°, β = 101.575(3)°, γ
1 2 1
= 0.0568, wR = 0.1345, R indices (all data): R
2
8
=
2
13
32 4
H O , CCDC 1500429, Mw = 600.67, crystal
Hz, 2H), 5.30 (d, J = 9.5 Hz, 2H), 3.66 (s, 6H), 2.17 (s, 6H) ppm;
NMR (CDCl , 125 MHz): δ = 155.4, 133.5, 133.4, 131.0, 130.3, 129.3,
3
1
1
C
3
1
28.7, 128.4, 128.3, 127.2, 127.0, 126.9, 126.5, 126.3, 126.1, 123.4,
16.7, 112.9, 57.0, 21.0 ppm; HR MS (ACPI): m/z 569.2475 [M+H] ;
3
–3
+
= 90°, V = 3033.8(14) Å , Z = 4, Dc = 1.315 Mg m , T = 173(2) K, μ =
–1
0
.083 mm , 23327 reflections measured, 6916 unique (Rint = 0. 0397),
final R indices [I2σ(I)]: R = 0.0715, wR = 0.1388, R indices (all data): R
0. 0845, wR = 0.1445.
Crystal data for rac-1f: C40
crystal size 0.47 x 0.42 x 0.24 mm , monoclinic, space group C2/c,, a =
6.819(20) Å, b = 16.585(17) Å, c = 12.4218(14) Å, α = 90°, β =
found: 569.2477.
Compound rac-1e: Yellow power (62%); M.p.: 234-235 C; H NMR
CDCl , 500 MHz): δ = 8.64 (dd, J = 6.2, 3.4 Hz, 2H), 8.25 (d, J = 8.7 Hz,
H), 7.68 (dd, J = 6.3, 3.2 Hz, 2H), 7.60 (d, J = 8.8 Hz, 2H), 7.48 (d, J =
.6 Hz, 2H), 7.22 (d, J = 8.8 Hz, 2H), 6.65 (dd, J = 8.5, 2.3 Hz, 2H), 6.36
1
2
1
1
=
2
(
2
8
3
H
2 2
26Cl O , CCDC 1500430, Mw = 609.51,
3
1
(dd, J = 8.5, 2.8 Hz, 2H), 5.84 (dd, J = 8.5, 2.8 Hz, 2H), 5.35 (dd, J = 8.5,
3
–3
13
121.740(12)°, γ = 90°, V = 2947(5) Å , Z = 4, Dc = 1.374 Mg m , T =
2
3
.2 Hz, 2H), 3.73 (s, 6H), 3.67 (s, 6H) ppm; C NMR (CDCl , 125 MHz):
–1
1
=
73(2) K, μ = 0.258 mm , 9904 reflections measured, 3318 unique (Rint
0. 0535), final R indices [I2σ(I)]: R = 0. 0935, wR = 0.2275, R indices
= 0.1020, wR = 0.2351.
Crystal data for M-1f: C40 , CCDC 1501288, Mw = 609.51, crystal
size 0.45 x 0.35 x 0.06 mm , tetragonal, space group P4322, a =
δ = 156.4, 155.5, 131.0, 130.3, 129.6, 129.4, 129.1, 128.8, 128.4, 127.3,
26.6, 126.0, 125.9, 123.4, 116.8, 113.0, 111.9, 111.5, 57.0, 55.2 ppm;
1
2
1
+
(all data): R
1
2
HR MS (ACPI): m/z 601.2373 [M+H] ; found: 601.2377.
Compound rac-1f: Yellow power (71%); M.p.: 299-300 C; H NMR
CDCl , 500 MHz): δ = 8.65 (dd, J = 6.2, 3.4 Hz, 2H), 8.30 (d, J = 8.7 Hz,
H), 7.72–7.65 (m, 4H), 7.58 (d, J = 8.6 Hz, 2H), 6.73 (dd, J = 8.3, 2.3 Hz,
H), 6.65 (dd, J = 8.3, 2.2 Hz, 2H), 6.23 (dd, J = 8.2, 2.3 Hz, 2H), 5.35
1
2 2
H26Cl O
3
(
2
2
3
1
=
2.065(4) Å, b = 12.065(4) Å, c = 68.81(3) Å, α = 90°, β = 90°, γ = 90°, V
10017(8) Å , Z = 12, Dc = 1.212 Mg m , T = 173(2) K, μ = 0.227 mm
3
–3
–1
,
13
63698 reflections measured, 9768 unique (Rint = 0. 0837), final R indices
I2σ(I)]: R = 0. 0663, wR = 0.1385, R indices (all data): R = 0. 0711,
wR = 0.1408.
(dd, J = 8.2, 2.2 Hz, 2H), 3.66 (s, 6H) ppm; C NMR (CDCl
3
, 125 MHz):
[
1
2
1
δ = 155.4, 134.6, 130.6, 130.28, 130.25, 130.2, 129.8, 128.8, 128.6,
1
5
2
28.5, 127.4, 127.0, 126.2, 125.8, 125.4, 125.0, 123.5, 117.2, 112.9,
7.0 ppm; HR MS (ACPI): m/z 609.1383 [M+H] ; found: 609.1385.
+
This article is protected by copyright. All rights reserved

Chemistry - An Asian Journal
10.1002/asia.201601305
FULL PAPER
Zhang, L. Shi, Z. Tang, C.-F. Chen, Chem. Commun. 2016, 52, 9921–
Acknowledgements
9
924.
12] a) W. H. Laarhoven, W. H. M. Peters, A. H. A. Tinnemans, Tetrahedron
978, 34, 769–777; b) M. C. Carreño, R. Hernández-Sánchez, J.
[
We thank the National Natural Science Foundation of China
1
(
21332008, 91527301, 21521002), and the Strategic Priority
Mahugo, A. Urbano, J. Org. Chem. 1999, 64, 1387−1390; c) Y.-Z.
Zhang, J. L. Petersen, K. K. Wang. Org. Lett. 2007, 9, 1025–1028; d)
Y.-Z. Zhang, J. L. Petersen, K. K. Wang. Tetrahedron 2008, 64, 1285–
Research Program of CAS (XDB12010400) for financial support.
1
293; e) K. Usui, K. Yamamoto, T. Shimizu, M. Okazumi, B. Mei, Y.
Keywords: helicene • chiroptical property • chiral resolution •
self-assembly • Suzuki coupling
Demizu, M. Kurihara, H. Suemune, J. Org. Chem. 2015, 80, 6502–
6508; f) A. M. Del Hoyo, A. Urbano, M. C. Carreño, Org. Lett. 2016, 18,
2
0−23.
[
[
1]
2]
a) Y. Shen, C.-F. Chen, Chem. Rev. 2012, 112, 1463–1535; b) M.
Gingras, Chem. Soc. Rev. 2013, 42, 968–1006.
[
[
[
[
[
13] X.-J. Li, M. Li, H.-Y. Lu, C.-F. Chen, Org. Biomol. Chem. 2015, 13,
628–7632.
7
a) F. Torricelli, J. Bosson, C. Besnard, M. Chekini, T. Burgi, J. Lacour,
Angew. Chem. 2013, 125, 1840–1844; Angew. Chem. Int. Ed. 2013, 52,
14] D. Waghray, J. Zhang, J. Jacobs, W. Nulens, N. Basaric, L. V. Meervelt,
W. Dehaen, J. Org. Chem. 2012, 77, 10176–10183.
1
796–1800; b) D. Mendola, N. Saleh, N. Vanthuyne, C. Roussel, L.
Toupet, F. Castiglione, T. Caronna, A. Mele, J. Crassous, Angew. Chem.
014, 126, 5896–5900; Angew. Chem. Int. Ed. 2014, 53, 5786–5790; c)
15] Y. Ogawa, M. Toyama, M. Karikomi, K. Seki, K. Haga, T. Uyehara,
Tetrahedron Lett. 2003, 44, 2167–2170.
2
16] J.-D. Chen, H.-Y. Lu, C.-F. Chen, Chem. Eur. J. 2010, 16, 11843–
K. Nakamura, S. Furumi, M. Takeuchi, T. Shibuya, K. Tanaka, J. Am.
Chem. Soc. 2014, 136, 5555–5558; d) D. Schweinfurth, M. Zalibera, M.
Kathan, C. Shen, M. Mazzolini, N. Trapp, J. Crassous, G. Gescheidt, F.
Diederich, J. Am. Chem. Soc. 2014, 136, 13045–13052.
11846.
17] F. H. Allen, O. Kennard, D. G. Watson, L. Brammer, A. G. Orpen, R.
Taylor, J. Chem. Soc., Perkin Trans. 2 1987, S1. The C-C bond length
in benzene is 1.39 Å. The Csp2-Csp2 single bond is ca. 1.48 Å, while the
[
3]
a) M. A. Shcherbina, X. B. Zeng, T. Tadjiev, G. Ungar, S. H. Eichhorn, K.
E. Phillips, T. J. Katz, Angew. Chem. 2009, 123, 7977–7980; Angew.
Chem. Int. Ed. 2009, 48, 7837–7840; b) Z.-H. Wang, J.-W. Shi, J.-G.
Wang, C.-L. Li, X.-Y. Tian, Y.-X. Cheng, H. Wang, Org. Lett. 2010, 12,
C
sp2=Csp2 double bond is ca. 1.32 Å.
18] a) M. B. Groen, G. Stulen, G. J. Visser, H. Wynberg, J. Am. Chem. Soc.
970, 92, 7218–7219; b) A. Brown, C. M. Kemp, S. F. Mason, J. Chem.
[
[
1
Soc. A 1971, 751–755; c) M. Nakazaki, K. Yamamoto, T. Ikeda, T.
Kitsuki, Y. Okamoto, J. Chem. Soc. Chem. Commun. 1983, 787–788.
19] a) L. C. Gilday, S. W. Robinson, T. A. Barendt, M. J. Langton, B. R.
Mullaney, P. D. Beer, Chem. Rev. 2015, 115, 7118–7195; b) O. V.
Shishkin, R. I. Zubatyuk, V. V. Dyakonenko, C. Lepetit, R. Chauvin,
Phys. Chem. Chem. Phys. 2011, 13, 6837–6848; c) F. F. Awwadi, D.
Taher, A. Maabreh, F. Z. Alwedian, H. AlEbaisat, T. Rꢀffer, H. Lang,
Struct. Chem. 2013, 24, 401−408.
4
56–459; c) K. Nakano, H. Oyama, Y. Nishimura, S. Nakasako, K.
Nozaki, Angew. Chem. 2012, 124, 719–723; Angew. Chem. Int. Ed.
012, 51, 695–699; d) T. Hatakeyama, S. Hashimoto, T. Oba, M.
2
Nakamura, J. Am. Chem. Soc. 2012, 134, 19600–19603.
[
4]
a) T. Fujikawa, Y. Segawa, K. Itami, J. Am. Chem. Soc. 2015, 137,
7
763–7768; b) H. Hirai, K. Nakajima, S. Nakatsuka, K. Shiren, J. Ni, S.
Nomura, T. Ikuta, T. Hatakeyama, Angew. Chem. 2015, 127, 13785-
3789; Angew. Chem. Int. Ed. 2015, 54, 13581–13585; c) T. Fujikawa,
1
Y. Segawa and K. Itami, J. Am. Chem. Soc. 2016, 138, 3587-3595; d) T.
Katayama, S. Nakatsuka, H. Hirai, N. Yasuda, J. Kumar, T. Kawai, T.
Hatakeyama, J. Am. Chem. Soc. 2016, 138, 5210–5213; e) H. Sakai, S.
Shinto, J. Kumar, Y. Araki, T. Sakanoue, T. Takenobu, T. Wada, T.
Kawai, T. Hasobe, J. Phys. Chem. C 2015, 119, 13937–13947; f) M. Li,
L.-H. Feng, H.-Y. Lu, S. Wang, C.-F. Chen, Adv. Funct. Mater. 2014, 24,
4405–4412; g) M. Li, W. Yao, J.-D. Chen, H.-Y. Lu, Y. Zhao, C.-F. Chen,
J. Mater. Chem. C 2014, 2, 8373–8380.
[
5]
a) K. Yavari, P. Aillard, Y. Zhang, F. Nuter, P. Retailleau, A. Voituriez, A.
Marinetti, Angew. Chem. 2014, 126, 880–884; Angew. Chem. Int. Ed.
2014, 53, 861–865; b) M. Gicquel, Y. Zhang, P. Aillard, P. Retailleau, A.
Voituriez and A. Marinetti, Angew. Chem. 2015, 127, 5560–5563;
Angew. Chem. Int. Ed. 2015, 54, 5470–5473.
[
[
6]
7]
N. Saito, K. Kanie, M. Matsubara, A. Muramatsu, M. Yamaguchi. J. Am.
Chem. Soc. 2015, 137, 6594–6601.
a) T. Verbiest, S. V. Elshocht, M. Kauranen, L. Hellemans, J.
Snauwaert, C. Nuckolls, T. J. Katz, A. Persoons, Science 1998, 282,
9
13−915; b) T. Verbiest, S. Sionke, A. Persoons, L. Vyklicky, T. J. Katz,
Angew. Chem. 2002, 114, 4038–4040; Angew. Chem. Int. Ed. 2002, 41,
882−3884.
3
[
8]
9]
a) J. E. Field, G. Muller, J. P. Riehl, D. Venkataraman, J. Am. Chem.
Soc. 2003, 125, 11808−11809; b) T. Kaseyama, S. Furumi, X. Zhang, K.
Tanaka, M. Takeuchi, Angew. Chem. 2011, 123, 3768–3771; Angew.
Chem. Int. Ed. 2011, 50, 3684−3687.
[
[
[
R. H. Janke, G. Haufe, E. U. Würthwein, J. H. Borkent, J. Am. Chem.
Soc. 1996, 118, 6031–6035
10] D. J. Morrison, T. K. Trefz, W. E. Piers, R. McDonald, M. Parvez, J.
Org. Chem. 2005, 70, 5309–5312
11] a) Y. Shen, H.-Y. Lu, C.-F. Chen, Angew. Chem. 2014, 126, 4736–4739;
Angew. Chem. Int. Ed. 2014, 53, 4648–4651; b) M. Li, H.-Y. Lu, C.
This article is protected by copyright. All rights reserved

Chemistry - An Asian Journal
10.1002/asia.201601305
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A series of 1,16-diarylbenzo[5]helicene
derivatives were synthesized, which
showed highly helical twisted structures
Wei-Bin Lin, Meng Li, Lei Fang, Yun
Shen, and Chuan-Feng Chen*
and
formed
hierarchical
packing
Page No. – Page No.
architectures with alternating P-layer and
M-layer in solid state. Moreover, optically
pure and stable enantiomers of the 1,16-
diarylbenzo[5]helicene derivatives were
also obtained, and they showed mirror
image CD spectra, high specific optical
Synthesis, Structures, Resolution
and Chiroptical Properties of
1,16-Diaryl Substituted
Benzo[5]helicene Derivatives
rotations,
and
formed
a
helical
nanotubular structure by the self-
assembly of one enantiomer via halogen
bondings.
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