Hydrogen bonding liquid crystalline benzoic acids with alkylthio groups: Phase transition behavior and insights into the cybotactic nematic phase

Article abstract of DOI:10.1039/c7nj00282c

A simple but novel class of hydrogen bonding liquid crystalline benzoic acids with alkylthio (or alkylsulfanyl; SR) groups was established. In general, although it is difficult for laterally non-substituted rod-like molecules with an alkylthio group to form some mesophases, the present molecules exclusively form a nematic (N) regime, owing to spontaneous carboxylic dimerization. It was found that the number of carbons in the alkylthio groups strongly correlated with transition temperatures as well as nematogenic stability: odd-even effects. Even-members displayed wider monotropic and enantiotropic N phases, despite the fact that almost all odd-members showed either none or only monotropic-narrower ones. Interestingly, their thermal transition temperatures were lower compared to those for alkoxy (OR) analogues, on account of the small angle (or large bend) of the C-S-C bond as well as the low electron density on their aromatic ring due to the weak electron donor properties of alkylthio groups. Additionally, in-depth wide-angle X-ray diffraction measurements revealed that an alkylthio analogue exhibited significantly enhanced smectic clusters formed in the N regime (or Ncyb phase) as well as the cluster type close to smectic (Sm) A, in comparison with an alkoxy analogue exhibiting a clear SmC-type cluster. The results indicate that a robust S?S intermolecular interaction for an alkylthio group into a mesogen affects the kind of smectic cluster in the Ncyb phase.

Full text of DOI:10.1039/c7nj00282c

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Jason B. Benedict et al.
The role of atropisomers on the photo-reactivity and fatigue of
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Hydrogen bonding liquid crystalline benzoic acids with alkylthio
groups: phase transition behavior and insights into cybotactic
nematic phase
Received 00th January 20xx,
Accepted 00th January 20xx
Yuki Arakawa,a* Yukito Sasaki,a Kazunobu Igawa,b and Hideto Tsuji a
DOI: 10.1039/x0xx00000x
A simple but novel class of hydrogen bonding liquid crystalline benzoic acids with alkylthio (or alkylsulfanyl; SR) groups was
established. In general, although laterally non-substituted rod-like molecules with an alkylthio group are difficult to form
some mesophases, the present molecules exclusively form a nematic (N) regime, owing to spontaneous carboxylic
dimerization. It was found that the number of carbons in the alkylthio groups strongly correlated with transition
temperatures as well as nematogenic stability; odd-even effects. Even-members displayed wider monotropic and
enantiortopic N phases, despite the fact that almost all odd-members showed either none or only monotropic-narrower
ones. Interestingly, their thermal transition temperatures were lower compared to those for alkoxy (OR) analogues, on
account of the small angle (or large bend) of the C–S–C bond as well as the low electron density on their aromatic ring due
to the weak electron donor properties of alkylthio groups. Additionally, in-depth wide-angle X-ray diffraction
measurements revealed that an alkylthio analogue exhibited significantly enhanced smectic clusters formed in the N
regime (or Ncyb phase) as well as the cluster type close to smectic (Sm) A, in comparison with an alkoxy analogue
exhibiting a clear SmC-type cluster. The results indicate that a robust S···S intermolecular interaction for an alkylthio group
into a mesogen affects the kind of smectic cluster in Ncyb phase.
www.rsc.org/
alkoxy groups display nematic (N) phase and subsequent
smectic (Sm) C (SmC) phases corresponding to the alkyl chain
length, and that they have smectic clusters containing shortꢀ
Introduction
Hydrogen bonding (HB) liquid crystalline (LC) (HBLC)
molecules attract considerable attention for liquid crystal
chemistry as well as supramolecular chemistry. In particular,
since the discovery of LC formation with respect to a multiple
component system between nonꢀmesogenic pyridine and
benzoic acid derivatives, established by Kato et al.,1 HBLC
chemistry has received an even greater attention on not only
lowꢀmolar mass molecules2 but also polymers.3
The most representative and versatile HBLC molecules
include benzoic acid derivatives that were first reported around
a hundred years ago.4 The spontaneous dimerization under
ambient conditions, leading to enlarged molecular anisotropy as
well as molecular polarizability anisotropy or a dipole moment,
can access its LC formation from the melt for its own singleꢀ
components. Accordingly, several literatures have been
reported with respect to the LC properties for benzoic acid
derivatives so far.5
range order in nematic phase (the so called cybotactic nematic
phase; Ncyb phase).5c,i Since Ncyb phase is considered as a key to
reveal biaxial nematic phase (Nb),6 which is a controversial
issue within LC chemistry from the view point of both
scientific concerns and applications,7 an understanding the LC
properties of the benzoic acid derivatives is of great interest. On
the other hand, benzoic acid derivatives are vitally important as
an ingredient of multiꢀcomponent HBLCs as stated above as
well as a starting material for the synthesis of new organic
materials along with organic LC materials.
In our previous report, we focused on the utilization of
carboxylic dimerization for diphenylꢀacetylene with an
alkylthio (or alkylsulfanyl: SR) group, to afford some
mesophases.8 This is because albeit that an alkylthio group has
beneficial effects on optical anisotropy (or birefringenece) due
to its high polarizability, it is known that laterally nonꢀ
substituted rodꢀlike molecules with an alkylthio group, as
shown in Fig. 1(a), hardly form some mesophases9. By
incorporating a carboxylic group wellꢀdefined enantiotropic
mesophases including N phase and a few Sm phases have been
induced on account of the hydrogen bond suppressing
crystallization ability relative to covalent bonds. Consequently,
the following remarkable feature was found; intermolecular
It is known that benzoic acid derivatives with alkyl and
S
···
S
interactions derived from alkylthio groups of
neighbouring molecules work well even in the most fluid N
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cooling scans performed at a rate of 3 °C minꢀ1 under a nitrogen
gas. WAXD measurements were conducted using a Bruker D8
DISCOVER equipped with a Vantecꢀ500 detector using CuꢀKα
radiation. The specimens were kept in glass capillary tubes (1.5
mm diameter) for oriented patterns under a magnetic field (
).
B
=
1
T
O
O
X
CmH2m+1 / KOH
Ethanol
HS
H2m+1CmS
OH
OH
BA-Sm
Scheme 1. Synthetic scheme of benzoic acids with alkylthio groups.
Fig. 1. Molecular structures of non-mesogenic diphenyl-acetylene with
hexylthio group (a) and mesogenic benzoic acids with alkylthio groups (b).
a
Synthesis
All the benzoic acids with alkylthio groups were synthesized
according to the Williamson ether reaction as shown in Scheme
1. They are abbreviated as BA–Sm, of which m refers to the
carbon numbers in the alkyl chains. As a representative of the
synthetic procedure, that of BA–SC6 is depicted below.
phase, resulting in enhanced Ncyb features compared to an
alkoxy derivative.
Based on the context as mentioned above, we speculated
that the dimeric forms of benzoic acids [q.v. Fig. 1(b)] could
show enhanced cybotactic nematic phase owing to alkylthio
groups. To the best of the author’s knowledge, the benzoic
acids with alkytlhio groups have not been reported, with the
exception of one literature,10 despite them being the simplest
and bottommost molecules. Therefore, their liquid
crystallinities or mesophase structures have never been revealed
thus far. Its development is highly significant for new HBLC
chemistry as well as in the design of subsequent LC materials.
In this study, we present the first report of the detailed
mesogenic structures for LC benzoic acids with alkylthio
groups. Derivatives with a carbon number of 1–8 were prepared
and some molecules successfully formed a wellꢀdefined N
phase. To clarify the effect of an alkylthio group on not only
the mesophase structure but also the crystal structure,
derivatives with hexylthio and hexyloxy (viz. the same carbon
chain) were inꢀdepth investigated by means of wide angle xꢀray
diffraction (WAXD) measurement with using each magneticꢀ
aligned specimen as well as singleꢀcrystal xꢀray diffraction
(XRD) measurement.
4ꢀhexylthio benzoic acid (BA–S6)
A mixture of 4ꢀmercaptobenzoic acid (2.00 g, 13.0 mmol), 1ꢀ
bromohexane (3.22 g, 19.5 mmol), KOH (2.19 g, 39.0 mmol)
and ethanol (30 mL) was stirred at reflux temperature for 12h.
After the reaction mixture was cooled to room temperature, 2M
HCl aq was added into the flask for neutralization until a
colorless solid was precipitated. The solid was filtrated and
washed with distilled water to afford the target compound.
Yield: 95%. 1H NMR (400 MHz, CDCl3) δ 7.98 (d,
Ar– , 2H), 7.31 (d, = 8.8 Hz, Ar– , 2H), 3.00 (t,
S–CH2, 2H), 1.71 (tt,
1.46 (tt, = 6.8 and 7.8 Hz, S–(CH2)2–CH2, 2H), 1.39–1.24 (m,
(CH2)2–CH3, 4H), 0.89 (t,
= 6.8 Hz, CH3, 3H) ppm. 13C NMR
J
J
= 8.8 Hz,
= 7.2 Hz,
H
J
H
J
= 7.2 and 7.8 Hz, S–CH2–CH2, 2H),
J
J
(100 MHz, CDCl3) δ 171.8, 146.0, 130.5, 126.3, 125.6, 32.1,
31.3, 28.7, 28.6, 22.5, 13.9 ppm. FTꢀIR spectra (KBr) ν 2955,
2918, 2872, 2850, 1686, 933 cmꢀ1.
Single crystal data of BA–S6
Representative crystal parameters are shown as follows; Crystal
system: monoclinic, space group: C2/c (No. 15), lattice
Experimental
parameters: a = 21.213(12) Å, b = 5.415(3) Å, c = 23.066(12)
Materials and methods
3
Å, β = 106.851(9) , V = 2536(2) Å , Z = 8, Dcalc = 1.248 g/cm3,
o
4ꢀmercaptobenzoic acid was purchased from TCI and Wako,
and 4ꢀhexyloxybenzoic acid and each alkyl halide were
purchased from TCI. 4ꢀhexyloxybenzoic acid was recrystallized
with methanol purchased from Kanto chemical. Ethanol for the
reaction solvent was purchased from Wako. Hydroxyl
R1 = 0.0506,
Cambridge Crystallographic Data Centre (CCDC) via
www.ccdc.cam.ac.uk/data_request/cif. CCDC 1523392
wR2 = 0.1413. The data are deposited on The
involves the supplementary crystallographic data for BA–S6.
1
potassium (KOH) was purchased from Nacalai tesque. The H
NMR and 13C NMR spectra were measured in CDCl3 on a
JEOL LNMꢀEX 400 and Avance III 400, respectively, at room
temperature using tetramethylsilane (TMS) as an internal
standard. FTꢀIR spectra were measured with a JASCO FT/IRꢀ
4200 with KBr (Wako) method. The optical textures were
observed by an Olympus BX50 POM with a Linkam LKꢀ
600PM hot stage, and the transition temperatures and enthalpies
were evaluated by a Shimadzu DSCꢀ60 with heating and
Results and discussion
FT-IR measurements on solid states
All the BA–Sm and a hexyloxy derivative (BA–O6) were
subject to FTꢀIR measurements in each solid state (KBr) at
room temperature. As a representative case, the FTꢀIR spectra
of BA–S6 and BA–O6 are shown in Fig. 2, which are discussed
elaborately. We can clearly see three major features for BA–S6
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due to the super cooling effect in comparison with those upon
heating. In particular, the N range for BA–S6 is the widest
value of 25°C among those for all analogues upon cooling, on
account of a considerable decrease in the transition temperature
from N phase to crystal phase. The above results apparently
suggest that mesophases can form more easily be easier to be
formed for even–m members compared to odd–m members;
oddꢀeven effect to mesogenic incidence. Additionally, Fig. 4(b)
illustrates the fidelity in the carbon numbers with respect to
transition temperatures from Iso to N phase upon cooling. The
temperatures for even–m members are higher than those for
oddꢀm members. These trends are similar to that of alkoxy
derivatives5a–f and opposite to that for alkyl derivatives,5f,g due
to the additional atom (sulfur or oxygen) between the
mesogenic core and the alkyl linkage. A similar fidelity is
observed for their enthalpies from Iso to N phase transition
upon cooling process. By and large, alkyl chains contribute to
mesogenic incidence and stability evidenced by the fact that
their mesophases become stable with an increase in alkyl chain
length. Notably, the two following distinct features for BA–Sm
are observed compared with the alkoxy derivatives in
literature.5b,c,e,f Firstly, BA–Sm exclusively display nematic
phase even in the long alkylꢀchain analog of BA–S8, although
alkoxy benzoic acids form SmC phase even on heptyloxy
analog. Next, the thermal transition temperatures are apparently
lower than those for alkoxy derivatives, which it is consistent
with previous reports.10,11 As discussed later, we speculated that
they could be ascribed to the steric hindrance derived from the
small angle (or large bend) of the C–S–C bond relative to the
C–O–C bond evidenced by single crystal Xꢀray analysis as well
as the weak electron donor property for SR group leading low
electron density on an aromatic ring (or weak intermolecular
attractive interaction) compared to an OR group.
Fig. 2. FT-IR spectra for BA–S6 (solid line) and BA–O6 (dotted line) on KBr
method at room temperature.
and BA–O6. Firstly, broad bands at the range from near 2500 to
3500 cmꢀ1 are detected. Next, the bands from the stretching
vibration of C=O for carboxylic acid are observed at
approximately 1680 cmꢀ1. It is known that in the case of alkoxyꢀ
benzoic acids existing in a monomeric form; in diluted solution,
the stretching vibration of C=O for carboxylic acid is observed
at 1760 cmꢀ1.5i Finally, the outꢀofꢀplane between H and OH
wagging vibration bands of carboxylic acid dimers at
approximately at 940 cm−1 are taken. Thus, similar trends are
observed for all BA–Sm shown in the the ESI. These results
establish the dimeric form in the solid state at room temperature
for all BA–Sm and BA–O6, as visualized for BA–S6 from its
single crystal.
Phase transition behavior
The thermal transition temperatures and enthalpies for each
compound are listed in Table 1, which were determined by
DSC measurements. The POM images and DSC traces of all
the compounds, excluding those for BA–S1 due to sublimation
and BA–S6 illustrated in the manuscript, are shown in ESI.
Since the sublimation was observed for the short alkyl chain
members (BA–S1 and BA–S2), their enthalpies on transitions
from the mesophases to isotropic (Iso) phases were not
determined. Here, some BA–Sm with relatively long alkyl
chains display N phase,10 despite the fact that laterally nonꢀ
substituted rodꢀlike molecules with alkylthio groups seldom
form any mesophases as described in the introduction. A
representative DSC trace with a POM image for BA–S6 is
shown in Fig. 3. It indicates that BA–S6 has enantiortopic N
phase evidenced by two transition peaks on both
heating/cooling process [Fig. 3(a)] and a schlieren texture with
two and four brushes [Fig. 3(b)]. For the sake of clarity, all the
phase diagrams as a function of the alkyl carbon number (m)
are illustrated in Fig. 4. Upon heating as shown in Fig. 4(a),
almost all compounds do not exhibit any mesophases, with the
exception of BA–S6 and BA–S8, of which their mesophase
ranges are 8.1 and 3.1°C, respectively. Upon cooling as shown
in Fig. 4(b), on the other hand, BA–S4 and BA–S7 also form
nematic phase, in addition to BA–S6 and BA–S8. N regimes
upon cooling for BA–S6 and BA–S8 are apparently expanded
Fig. 3. DSC curve at a rate of 3°C min-1 (a) and POM image at 110°C upon cooling
for BA–S6 (b).
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Table1. Thermal transition temperatures (T: °C) and enthalpies (ΔH: kJ mol-1) upon
second heating (upper line) and first cooling (bottom line) at a rate of 3°C min-1
WAXD measurements on nematic regimes
.
In order to elucidate the effect of alkylthio substitution into N
phase structures in detail, we carried out WAXD measurements
using specimens oriented by applying a magnetic field. For
comparison, we employed the derivatives with the same alkyl
length of 6, viz. BA–O6 and BA–S6. The 2DꢀWAXD patterns
obtained for BA–O6 and BA–S6 on each N regime are shown
in Fig. 5(a) and 5(b), respectively. Two halos in the wideꢀangle
region, corresponding to the diffractions derived from mean
Cr
N
Iso
Compd.
BA–S1
T
ΔH
T
ΔH
b
-
・
・
・
・
193a
188
・
・
・
・
b
-
b
-
BA–S2
145.5a
140.5
lateral intermolecular distance
(dwax), indicate that the
b
-
molecular long axes on both specimens well oriented along the
magnetic field direction represented by arrows. From the
diffractions, dwax values were evaluated and their temperature
dependence from Iso to N phase is illustrated in Fig. 6, where
BA–S3
BA–S4
BA–S5
BA–S6
BA–S7
BA–S8
・
・
・
・
・
・
・
・
・
・
・
・
144.7
114.8
120.8
110.1
113.8
108.3
103.9
86.2
21.5
20.8
21.9
19.9
25.2
24.6
23.7
22.6
28.7
27.8
23.5
23.8
・
・
・
・
・
・
・
・
・
・
・
・
TIN and
T refer to the transition temperature from Iso to N
・
114.3
0.9
phase, and measurement temperature, respectively. Here, it
should be noted that the proximity among lateral molecules
appears even in Iso phase for BA–S6 compared to BA–O6. The
dwax value of 4.6 Å for BA–S6 is less than 4.7 Å for BA–O6,
implying the existence of S···S interaction in Iso phase. In
addition, the dwax on N regime for BA–S6 is apparently smaller
relative to that of BA–O6 at a range of similar TIN–T. During
the course of cooling, the dwax values for both compounds
gradually decrease with a decrease in temperature.
・
・
112.0
111.1
1.1
0.9
113.5
98.6
・
・
・
104.4
109.5
108.6
0.7
1.0
1.1
106.3
97.6
a Upon first heating.
b Not determined due to sublimation.
Fig. 5. The 2D-WAXD patterns obtained for magnetically aligned specimens of
BA–S6 (a) and BA–OC6 (b) on each nematic regime at 95°C. The scan directions
to obtain respective 1D-WAXD patterns in small angle regions are described in
(c).
Fig. 4. Phase diagrams obtained upon heating (a) and cooling (b) at a rate of 3°C
min-1.
4 | J. Name., 2012, 00, 1-3
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decrease in temperature, the molecular density in the clusters
gradually becomes higher. Consequently, the mobility of alkyl
chains tends to be disturbed with lowering temperature, leading
to the growing dsax(mer). Whereas, the dsax(dia) for BA–S6
seem mostly unchanged within nematic temperatures, contrary
to the dsax(mer).
With respect to BA–O6 forming clear NcybC phase, dsax(dia)
soakingly changes from 21 to 19 Å with a decrease in
temperature. This temperature dependence is similar to that of
SmC phase, in which the molecular tilt against layer normal
becomes larger with a lowering temperature. While, dsax(mer)
exhibits a nearly molecular dimeric form length of 32 Å over a
Fig. 6. Mean lateral intermolecular distance (dwax) for BA–S6 (circle) and BA–O6
(square).
Next, let us discuss the diffractions in each small angle
region. As shown in Fig. 5(a), it is clear that four diffused spots
split on opposite sides of the meridional line are observed for
BA–O6. This result is reminiscent of the existence of smectic C
like clusters in the N regime; molecules in each layer tilt
against layer normal (the so called cybotactic nematic C phase;
NcybC). As can be seen in Fig. 5(b), whereas, such diffraction
split is unclear in a visual manner for BA–S6. In Fig. 7, the
scans on the azimuthal angle of the innermost sprit diffractions
for both compounds are performed, to estimate the mean tilt
angle in the SmC like clusters, χ/2, which are tabulated in Table
2. That for BA–O6 exceeds over a large value of 50°
throughout its N regime. By Fig. 7, the diffraction split is
visualized for BA–S6 too. However, it is apparently undefined
compared to that of BA–O6. The χ/2 values of more or less 40°
over a range of N phase for BA–S6 are significantly smaller
than those of BA–O6. The reduction of the χ/2 values is thought
to be due to the S···S contacts; the intermolecular attractive
interaction among the sulfur atoms on neighbouring molecules.
These results allow us to speculate that the cluster type in the
nematic phase of BA–S6 proceeds to smectic A; molecules in
each layer do not tilt against layer normal (the so called
cybotactic nematic A phase; NcybA) (vide infra).
Fig. 7. Azimuthal profiles of the diffraction of the small angle region for BA–S6
(bottom solid line) and BA–O6 (top dotted line).
Table 2. WAXD profile parameters for each small angle region on temperature
dependence for BA–S6 and BA–O6.
dsax (Å)
χ/2
a
Compd.
BA-S6
T (°C)
Isax/Iwax
(°)
(azi)
(mer) (dia)
95
98
28.4
27.4
27.4
26.8
26.5
25.2
21.7
19.8
20.0
20.9
22
31.9 23.7
31.2 23.2
30.4 23.4
1.8
1.7
1.6
1.5
1.4
1.2
0.8
1.3
1.3
1.2
1.2
1.2
1.1
0.8
45
44
42
42
40
38
-
101
104
107
110
116b
100
105
115
130
140
149
160b
In order to verify the speculation, we carried out three
typesscans in the small angle region of 2DꢀWAXD patterns
described in Fig. 5(c); a scan along the meridian direction
(meridian scan), split direction (diagonal scan) and direction on
the azimuthal angle (azimuthal scan). The azimuthal scan
includes up to the diffractions in the wideꢀangle regions. The
29.7
24
29.1 24.5
28.4 24.2
-
-
BA-O6
31.7 19.1
31.7 19.3
31.2 19.6
31.5 20.1
30.5 20.3
29.5 20.9
53
53
52
52
51
51
-
obtained dꢀspacing, given as dsax(mer), dsax(dia) and dsax(azi)
from these diffractions, means the layer spacing is derived from
the cluster type of SmA, SmC, and their combinations,
respectively. Their temperature dependences for BA–S6 and for
BA–O6 also are compiled in Table 2.
When transited from Iso to N phase, dsax(mer) for BA–S6 is
28 Å at 110°C, which is shorter than the dimeric form length of
32 Å evaluated from a single crystal XRD measurement. Then,
it clearly increases with a decrease in temperature, and finally is
close to the dimeric form length at the lowest N temperature of
95°C. This trend can be explained as follows; at a high
temperature on N regime, the nematogenic molecules largely
deviate from the nematic director or the direction of the
magnetic field, indicative of a lowꢀorder parameter. With a
22.7
23
19.4
-
-
a Evaluated from the scans on the azimuthal line (azimuthal scans).
b Isotropic phase.
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range of N regime and are nearly unchanged. The dsax(mer) for with decreasing temperatures, until it finally reaches the high
BA–O6 may imply the diffraction from transitionally formed value of 1.8. Generally, it is known that normal nematogenic
SmA like clusters or free molecules.
molecules display Isax/
Iwax < 1.12 The results mean that shortꢀ
For the purpose of clarity, additionally, the 1DꢀWAXD range positional correlations are strongly enhanced for BA–S6
patterns obtained from azimuthal scans for BA–S6 and BA–O6 due to S···S interactions. Although BA–O6 also exhibits
are shown in Fig. 8. As can be seen in Fig. 8(a), the diffraction relatively high values (Isax
maxima on the small angle region for BA–S6 gradually shifts to temperature dependent over the entire mesophase range.
a smaller angle of 2 with decreasing temperature, indicating On the other hand, it is known that a magnetic field greatly
that diffraction for the meridian scan is superior to that for the influences nematicꢀphase behavior.13 Therefore, we performed
diagonal scan. The temperature dependence of 2 shift is the WAXD measurement for both specimens without
/Iwax ≈ 1.2), it is only slightly
θ
θ
a
similar to smectic A phase. That is to say, NcybA propensity magnetic field, too. The obtained 1DꢀWAXD patterns for both
could be predominant for BA–S6 but transitionally molecules are shown in supporting information. It is estimated
synchronous with NcybC evidenced by the fact that an undefined that the Isax/Iwax values are 1.3 for BA–S6 at 101°C and 1.0 for
BA–O6 at 115°C. These results indicate that BA–S6 and BA–
O6 exhibit Ncyb phase in the case without magnetic field, too,
and that an alkylthio group has a beneficial effect in enhanced
Ncyb phase compared to an alkoxy group, which is consistent
with the results obtained under the condition with magnetic
field. In addition, comparing the values with and without a
magnetic field for both molecules, the former is apparently
larger than the latter, indicating that the magnetic field
enhanced cybotactic nematic tendency.
Throughout the above WAXD investigations into benzoic
acids with hexylthio and hexyloxy groups, we can safely
explain the effects of a sulfur atom on rodꢀlike nematogenic
molecules, and offer a probable molecular arrangement in their
Sm clusters as shown in Fig. 10. The S···
S attractive
interactions work well even in fluid phases so that alkylthio
groups
Fig. 8. The temperature dependences of the 1D-WAXD patterns for BA–S6 (a)
and BA–O6 (b).
Fig. 9. The temperature dependences of Isax/Iwax values for BA–S6 (circle) and BA–
O6 (square).
split was detected. On the other hand, the diffraction maxima
for BA–O6 apparently moves to wide angle of 2θ, reflecting the
NcybC due to the temperature dependence of the SmC like
cluster in the N phase.
From the view point of the diffraction intensity ratio
between the small angle region (Isax) and the wideꢀangle halo
(
Iwax), (viz. Isax/Iwax), their cybotactic nematic tendency was
evaluated. The temperature dependence for each compound is
summarized in Table 2 and Fig. 9. It is noteworthy that the
Isax/Iwax for BA–S6 increases more steeply than that for BA–O6
6 | J. Name., 2012, 00, 1-3
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BA–O6 displays O···O contacts, and molecules are packed in
parallel with each other on the phenyl ring plane in contrast
with BA–S6 molecules.
Next, the geometries of each single molecule are discussed.
The crystal lattice for BA–O6 contains six independent
molecules,16 in which a similar result was obtained with our
measurements as well. While, it was found that BA–S6 has
molecules with single geometry in the lattice. With respect to
the comparison of the dihedral angles between the mean plane
of aliphatic chains and that of aromatic rings, BA–O6 exhibits
six values between 1.0° and 6.0°, and BA–S6 shows a single
value of 4.8°, indicating that the dihedral angles are nearly
unchanged with each other. On the other hand, the bond angles
of C–S–C at the base of the phenyl ring for BA–S6 of 104.7°
are much smaller than mean for those of C–O–C for BA–O6
(approximately 120°), indicative of a large bend for an
alkylhthio group. Such a large bend of an alkylthio group could
have steric hindrance to lead to the three following specific
features for rodꢀlike molecules with alkylthio groups compared
to alkoxy counterparts; intrinsically poor liquid crystallinity,
relatively low transition temperatures and nematogenic
propensity. Furthermore, it was reported that the rotation barrier
of an alkylthio group is lower than that of alkoxy group, which
also supports the above features.16
Fig. 10. Molecular organization model of the smectic clusters in the nematic
phase of for alkoxy benzoic acids (a) and alkylthio benzoic acids (b).
contribute to not only the strongly enhanced cybotactic nematic
phase but also the tendency for Sm A like cluster formations in
the N phase, explained by an increase in the Isax/Iwax value and
reduced tilt angle compared with those for an alkoxy analog.
XRD measurement for a single crystal of BA–S6
Single crystals of BA–S6 were obtained by recrystallization
from methanol solution, and a single crystal XRD measurement
was carried out to afford the molecular packing structure in the
crystal phase as shown in Fig. 11. Firstly, the geometries for
molecular packing are argued. Fig. 11 visualizes the dimeric
forms by hydrogen bond for BA–S6. The hydrogen bond
distance in the dimers (viz. the dimeric distance between
C=O···H–O) of 1.66 Å is the usual value for conventional
carboxylic dimers. In marked contrast with the crystal
structures for various sulfurꢀcontaining molecules,14
unexpectedly, S···S contacts close to S atoms in the lateral
molecules are not observed in the crystal packing for BA–S6.
Hammett constants and chemical shifts of aromatic protons
In addition, the intrinsically poor liquid crystallinity and
relatively
lowꢀtransitionꢀtemperature
phenomena
and
nematogenic propensity observed for rodꢀlike molecules with
alkylthio groups reported so far could also be thought to be due
to the electron density on an aromatic ring. According to the
empirical Hammett constants, which means the electron
donating and accepting properties for benzoic acid derivatives,
those for SMe, SEt and OMe at paraꢀpositions are 0.00, 0.03
and ꢀ0.27, respectively.17 These values suggest that alkylthio
groups at paraꢀpositions for benzoic acids have no or
significantly weak donating properties, while alkoxy groups
have an apparently electronꢀdonating property. That is, it
suggests that although the former hardly affects the electron
density on an aromatic ring, the latter renders an aromatic ring
electronꢀrich. Our results on 1H NMR characterizations are
definitely in good agreement with the consideration of the
Hammett constants. The chemical shifts derived from two
species of protons on an aromatic ring are 7.98 and 7.31 for
BA–S6, and 8.05 and 6.93 for BA–O6, respectively. So, that
means the aromatic protons are well shielded for BA–O6
compared to BA–S6. In other words, an alkylthio group at a
para position leads less electron density on an aromatic ring
Fig. 11. Molecular packing in the unit cell of BA–S6.
than an alkoxy group, resulting in weak CH···π and/or π···
π
intermolecular interactions. These results allow us to speculate
that not only a small angle of C–S–C bonding (or a large bend)
but also less electron density on an aromatic ring contribute to
intrinsically poor liquid crystallinity and relativeꢀlow transitionꢀ
temperature phenomena as well as nematogenic propensity for
rodꢀlike molecules with alkylthio groups, compared to alkoxy
counterparts.
Whereas, apparent CH···π interaction between laterally phenyl
rings of neighbouring molecules are noticed. It was assumed
that the CH···π interaction that took place between lateral
molecules could predominantly work during the crystallization
process as an alternative to S···S interaction. Based on Ref.
[15] and our measurement, on the other hand, the single crystal
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ARTICLE
Journal Name
13449; (l) A. A. Vieira, E. Cavero, P. Romero, H. Gallardo, J.
L. Serrano and T. Sierra, J. Mater. Chem. C, 2014, 2, 7029;
(m) B. Feringán, P. Romero, J. L. Serrano, R. Giménez and T.
Sierra, Chem. Eur. J., 2015, 21, 8859; (n) D. Miyajima, F.
Araoka, H. Takezoe, J. Kim, K Kato, M. Takata, T. Aida,
Science, 2012, 336, 209; (o) M. Parra, P. Hidalgo and J.
Alderete, Liq. Cryst., 2005, 32, 449; (p) S. M. Jansze, A.
MartínezꢀFelipe, J. M. D. Storey, A. T. M. Marcelis and C. T.
Imrie, Angew. Chem. Int. Ed., 2015, 54, 643; (q) M.
Roohnikan, M. Ebrahimi, S. R. Ghaffarian and N. Tamaoki,
Liq. Cryst., 2013, 40, 314; (r) M. D. Miranda, F. V. Chávez,
T. M. R. Maria, M. E. S. Eusebio, P. J. Sebastião and M. R.
Silva, Liq. Cryst., 2014, 41, 1743.
Conclusions
In this article, we describe the first report of the detailed liquid
crystallinity of hydrogen bonding LC benzoic acids with
alkylthio groups. Some BA–Sm displayed nematic phase owing
to hydrogen bonding dimerization. Their nematic temperatures
are lower than those for alkoxy counterparts.
Based on the WAXD measurement for BA–S6 and alkoxy
BA–O6, it was found that BA–S6 exhibited enhanced Ncyb
phase with a predominant NcybA propensity relative to BA–O6
exhibiting clear NcybC phase, on account of the intermolecular
S
···S interaction.
3
(a) T. Kato and J. M. J. Fréchet, Macromolecules, 1989, 22,
3818; (b) T. Kato, N. Mizoshita, K. Kanie, Macromol. Rapid.
Commun., 2001, 22, 797; (c) C. G. Bazuin and F. A. Brandys,
Chem. Mater., 1992, 4, 970; (d) I. M. Saez and J. W. Goodby,
J. Mater. Chem., 2005, 15, 26; (e) U. Beginn, Prog. Polym.
Sci., 2003, 28, 1049; (f) M. Lee, B. K Cho and W. C. Zin,
Chem. Rev., 2001, 101, 3869; (g) D. J. Broer, C. M. W.
Bastiaansen, M. G. Debije and A. P. H. J. Schenning, Angew.
Chem. Int. Ed., 2012, 51, 7102; (h) F. Vera, C. Almuzara, I.
Orera, J. Barberá, L. Oriol, J. L. Serrano and T. Sierra, J.
Polym. Sci. Pol. Chem., 2008, 46, 5528; (i) J. Del Barrio, E.
Blasco, C. Toprakcioglu, A. Koutsioubas, O. A. Scherman, L.
Oriol and C. SánchezꢀSomolinos, Macromolecules, 2014, 47,
897; (j) J. Vapaavuori, V. Valtavirta, T. Alasaarela, J.
Mamiya, A. Priimagi, A. Shishido and M. Kaivola, J. Mater.
Chem. C, 2011, 21, 15437; (k) S. J. Wang, R. Y. Zhao, S.
Yang, Z. Q. Yu and E. Q. Chen, Chem. Commun., 2014, 50,
8378; (l) T. Y. Lai, C. Y. Cheng, W. Y. Cheng, K. W. Lee
and S. H. Tung, Macromolecules, 2015, 48, 717; (m) T.
Ozawa, M. Kondo, J. Mamiya and T. Ikeda, J. Mater. Chem.
The single crystal XRD measurements revealed a larger bend
for C–S–C than C–O–C. In addition, Hammett constants and
chemical shifts of aromatic protons suggested that electron
density on an aromatic ring for BA–S6 is lower than that for
BA–O6, speculating that the CH–π and/or π–π intermolecular
interactions are lower for BA–S6 than for BA–O6. The above
results, including the small angle of C–S–C and the low
electron density on an aromatic, could be able to contribute to
the following distinct features for rodꢀlike molecules with an
alkylthio group compared to conventional alkoxy counterparts;
(1) intrinsically poor liquid crystallinity, (2) relatively low
phase transition temperature, and (3) nematogenic tendency.
These findings are beneficial in providing fundamental
insights into molecular structureꢀmesophase relations for
hydrogenꢀbonding liquid crystalline materials as well as novel
molecular designs based on sulfurꢀcontaining, rodꢀshaped LC
materials.
C
, 2014, 2, 2313; (n) M. Kondo, M. Takemoto, R. Fukae and
N. Kawatsuki, Polym. J., 2012, 44, 410
4
5
A. E. Bradfield, B. Jones and J. N. Rây, J. Chem. Soc., 1929,
2660.
(a) G. W. Gray and B. Jones, J. Chem. Soc., 1953, 4179; (b)
A. J. Herbert, Trans. Faraday Soc., 1967, 63, 555; (c) A.
Blumstein and L. Patel, Mol. Cryst. Liq. Cryst., 1978, 48,
Acknowledgements
This work was partly supported by JSPS KAKENHI Grant
number 15H06285, and research grants from The Nitto
Foundation and The Toukai Foundation for Technology. The
authors thank Prof. Masatoshi Tokita for WAXD measurements.
151; (d) R. F. Bryan and P. Hartley, Mol. Cryst. Liq. Cryst.
,
1980, 62, 259; (e) R. F. Bryan, P. Hartley, R. W. Miller and
M. S. Shen, Mol. Cryst. Liq. Cryst., 1980, 62, 281; (f) L. G.
Kuz’mina, S. M. Pestov, A. N. Kochetov, A. V. Churakov
and E. Kh. Lermontova, Crystallogr. Rep+., 2010, 55, 786;
(g) J. R. Pound, A. Zaki and H. Fahim, J. Chem. Soc., 1942,
307; (h) N. K. Lokanath, M. A. Sridhar, D. Revannasiddaiah
and J. Shashidhara Pasad, Liq. Cryst., 2000, 27, 767; (i) A.
Notes and references
1
T. Kato and J. M. J. Fréchet, J. Am. Chem. Soc., 1989, 111,
8533.
Sparavigna, A. Mello and B. Montrucchio, Phase Transit.
,
2
(a) T. Kato, N. Mizoshita and K. Kishimoto, Angew. Chem.
Int. Ed., 2006, 45, 38; (b) T. Kato, T. Matsuoka, M. Nishii, Y.
Kamikawa, K. Kanie, T. Nishimura, E. Yashima and S. Ujiie,
Angew. Chem. Int. Ed., 2004, 43, 1969; (c) Y. Sagara and T.
Kato, Nature Chem., 2009, 1, 605; (d) J. W. Goodby, I M.
Saez, S. J. Cowling, V. Görtz, M. Draper, A. W. Hall, S. Sia,
G. Cosquer, S. E. Lee and E. P. Raynes, Angew. Chem. Int.
Ed., 2008, 47, 2754; (e) C. M. Paleos and D. Tsiourvas, Liq.
Cryst., 2001, 28, 1127; (f) K. Kishikawa, S. Nakahara, Y.
Nishikawa, S. Kohmoto and Makoto Yamamoto, J. Am.
Chem. Soc., 2005, 127, 2565; (g) B. Roy, P. Bairi and A. K.
Nandi, RSC Adv., 2014, 4, 1708; (h) N. Gimeno, M. B. Ros
and J. L. Serrano, Chem. Mater., 2008, 20, 1262; (i) F. Vera,
R. M. Tejedor, P. Romero, J. Barberá, M. B. Ros, J. L.
Serrano and T. Sierra, Angew. Chem., Int. Ed., 2007, 46,
1873; (j) M. Amorín, A. Pérez, J. Barberá, H. L. Ozores, J. L.
Serrano, J. R. Granja and T. Sierra, Chem. Commun., 2014,
50, 688; (k) M. Cano, A. SánchezꢀFerrer, J. L. Serrano, N.
Gimeno and M. B. Ros, Angew. Chem. Int. Ed., 2014, 53,
2006, 79, 293; (j) S. I. Torgova, L. Komitov and A. Strigazzi,
Liq. Cryst., 1998, 24, 131; (k) T. Shimogaki, S. Dei, K. Ohta
and A. Matsumoto, J. Mater. Chem., 2011, 21, 10730; (l) T.
Iwata, R. Miyata and A. Matsumoto, Chem. Lett., 2013, 42,
849; (m) W. He, G. Pan, Z. Yang, D. Zhao, G. Niu, W.
Huang, X. Yuan, J. Guo, H. Cao and H. Yang, Adv. Mater.
,
2009, 21, 2050.
6
(a) A. de Vries, J. Mol. Liq., 1986, 31, 193; (b) P. Sarkar, P.
K. Sarkar, S. Paul and P. Mandal, Phase Transit., 2000, 71, 1;
(b) C. Keith, A. Lehmann, U. Baumeister, M. Prehm and C.
Tschierske, Soft Matter, 2010, 6, 1704; (c) O. Francescangeli
and E. T. Samulski, Soft Matter, 2010, 6, 2413; (d) O.
Francescangeli, F. Vita, C. Ferrero, T. Dingemans and E. T.
Samulski, Soft Matter, 2011, 7, 895; (e) F. Vita, T. Tauscher,
F. Speetjens, E. T. Samulski, E. Scharrer and O.
Francescangeli, Chem. Mater., 2014, 26, 4671; (f) F. Vita, K.
Sparnacci, G. Panzarasa, I. F. Placentino, S. Marino, N.
Scaramuzza, G. Portale, E. D. Cola, C. Ferrero, S. I. Torgova,
G. Galli, M. Laus and O. Francescangeli, ACS Macro Lett.
,
8 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
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Page 9 of 11
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Journal Name
ARTICLE
2014, 3, 91; (g) W. Nishiya, Y. Takanishi, J. Yamamoto and
A. Yoshizawa, J. Mater. Chem. C, 2014, 2, 3677; (h) P. K.
Karahaliou, P. H. J. Kouwer, T. Meyer, G. H. Mehl and D. J.
Photinos, J. Phys. Chem. B, 2008, 112, 6550; (i) L.
Chakraborty, N. Chakraborty, D. D. Sarkar, N. V. S. Rao, S.
J. Mater. Chem., 2007, 17, 3427; (h) Q. Xiao, T. Sakurai, T.
Fukino, K. Akaike, Y. Honsho, A. Saeki, S. Seki, K. Kato, M.
Takata and T. Aida, J. Am. Chem. Soc., 2013, 135, 18268; (i)
Y. S. Yang, T. Yasuda, H. Kakizoe, H. Mieno, H. Kino, Y.
Tateyama and C. Adachi, Chem. Commun., 2013, 49, 6483.
Aya, K. Van Le, F. Araoka, K. Ishikawa, D. Pociecha, E. 15 A. N. Kochetov, L. G. Kuz’mina, A. V. Churakov, N. S.
Goreckac and H. Takezoe, J. Mater. Chem. C, 2013, 1, 1562; Rukk and S. M. Pestv, Crystallogr. Rep+., 2006, 51, 53.
(j) H. H. Chen, H. A. Lin, Y. H. Lai, S. Y. Lin, C. H. Chiang, 16 X. D. Li, S. K. Lee, S. Kang, M. Tokita, S. Kawauchi and J.
H. F. Hsu, T. L. Shih, J. J. Lee, C. C. Lai and T. S. Kuo, Watanabe, Chem. Lett., 2009, 38, 424.
Chem. Eur. J., 2012, 18, 9543; (k) M. Tokita, A. Ikoma, T. 17 (a) R. W. Taft Jr. and I. C. Lewis, J. Am. Chem. Soc., 1958,
Ishii, S. Kang, J. Watanabe and T. Matsuoka,
Macromolecules, 2012, 45, 4857; (l) E. J. Choi, Y. H. Seo, T.
Kamal, S. Y. Park, J. Watanabe, Polymer, 2014, 55, 1931;
(m) Y. Kimoto, A. Nishizawa, Y. Takanishi, A. Yoshizawa
and J. Yamamoto, J. Phys. Chem. B, 2013, 117, 6290.
80, 2436; (b) D. H. McDaniel and H. C. Brown, J. Org.
Chem., 1958, 23, 420; (c) C. Hansch, A. Leo and R. W. Taft,
Chem. Rev., 1991, 97, 165.
7
(a) M. J. Freiser, Phys. Rev. Lett., 1970, 24, 1041; (b) L. J. Yu
and A. Saupe, Phys. Rev. Lett., 1980, 45, 1000; (c) D. W.
Bruce, Chem. Rec., 2004, 4, 10; (d) C. Tschierske and D. J.
Photinos, J. Mater. Chem., 2010, 20, 4263; (e) E. T.
Samulski, Liq. Cryst., 2010, 37, 669; (f) Biaxial Nematic
Liquid Crystals: Theory, Simulation and Experiment (Ed. by
G. R. Luckhurst and T. J. Sluckin). Wiley, 2015; (g) V.
Prasad, S. W Kang, K. A. Suresh, L. Joshi, Q. Wang and S.
Kumar, J. Am. Chem. Soc., 2005, 127, 17224; (h) K. Fu, M.
Sone, M. Tokita and J. Watanabe, Polym. J., 2006, 38, 442;
(i) M. Lehmann, J. Seltmann, A. A. Auer, Eric Prochnow and
U. Benedikt, J. Mater. Chem., 2009, 19, 1978; (j) K.
Neupane, S. W. Kang, S. Sharma, D. Carney, T. Meyer, G. H.
Mehl, D. W. Allender, Satyendra Kumar and S. Sprunt, Phys.
Rev. Lett., 2006, 97, 207802; (k) G. R. Luckhurst, Thin Solid
Films, 2001, 393, 40; (l) B. R. Acharya, A. Primak and S.
Kumar, Phys. Rev. Lett., 2004, 92, 145506; (m) L. A.
Madsen, T. J. Dingemans, M. Nakata, E. T. Samulski, Phys.
Rev. Lett., 2004, 92, 145505.
8
9
Y. Arakawa, S. Kang, J. Watanabe and G. Konishi, RSC Adv.
2015, 5, 8056.
,
(a) M. Hird, A. J. Seed, K. J. Toyne, J. W. Goodby, G. W.
Gray and D. G. McDonnell, J. Mater. Chem., 1993, 3, 851;
(b) A. J. Seed, K. J. Toyne and J. W. Goodby, J. Mater.
Chem., 1995, 5, 653; (c) A. J. Seed, K. J. Toyne and J. W.
Goodby, J. Mater. Chem., 1995, 5, 2201; (d) A. J. Seed, K. J.
Toyne, M. Hird and J. W. Goodby, Liq. Cryst., 2012, 39, 403;
(e) G. J. Cross, A. J. Seed, K. J. Toyne, J. W. Goodby, M.
Hird and M. C. Artal, J. Mater. Chem., 2000, 10, 1555.
10 H. T. Nguyen, C. Destrade, R. J. Twieg and K. Betterton, Liq.
Cryst., 1990, 8, 419.
11 (a) Y. Arakawa, S. Kang, H. Tsuji, J. Watanabe and G.
Konishi, RSC Adv., 2016, 6, 16568; (b) Y. Arakawa, S. Kang,
H. Tsuji, J. Watanabe and G. Konishi, RSC Adv., 2016, 6,
92845; (c) Y. Arakawa and H. Tsuji, accepted to Mol. Cryst.
Liq. Cryst.
12 A. de Vries, Mol. Cryst. Liq. Cryst., 1970, 10, 219.
13 (a) O. Francescangeli, F. Vita, F. Fauth and E. T. Samulski,
Phys. Rev. Lett., 107, 207801; (b) O. Francescangeli, F. Vita,
C. Ferrero, T. Dingemans and E. T. Samulski, Soft Matter
,
2011, 7, 895; (c) C. Zhang, S. Chakraborty, T. Ostapenko, S.
Sprunt, A. Jakli and J. T. Gleeson. Phys. Rev. E, 2012, 86,
020704.
14 (a) Y. Mazaki and K. Kobayashi, J. Chem. Soc., Perkin
Trans. 2, 1992, 761; (b) J. Dai, M. Munakata, L. P. Wu, T.
KurodaꢀSowa and Y. Suenaga, Inorg. Chim. Acta, 1997, 258,
65; (c) M. Iwaoka, S. Takemoto, M. Okada and S. Tomoda,
Bull. Chem. Soc. Jpn., 2002, 75, 1611; (d) D. B. Werz, R.
Gleiter and F. Rominger, J. Am. Chem. Soc., 2002, 124,
10638; (e) R. Gleiter and D. B. Werz, Chem. Lett., 2005, 34,
126; (f) K. Kobayashi, H. Masu, A. Shuto and K. Yamaguchi,
Chem. Mater., 2005, 17, 6666; (g) M. A. Stokes, R. Kortan,
S. R. Amy, H. E. Katz, Y. J. Chabal, C. Kloc and T. Siegrist,
This journal is © The Royal Society of Chemistry 20xx
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New Journal of Chemistry
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A novel class of hydrogen bonding liquid crystalline benzoic acids with alkylthio groups
was established and their phase transition behavior was investigated in detail.

Page 11 of 11
New Journal of Chemistry
Novel liquid crystalline benzoic acids with alkylthio groups
S
O
S・・・S attractive
interaction
alkoxy analogue
・Close neighboring molecules
・Reduced tilt angle