Liquid crystalline behaviors of three series of hockey stick-like compounds

Article abstract of DOI:10.1080/15421406.2020.1811015

Three series of meta-perfluoroalkylphenol esters are synthesized. Both SmA and SmC phases are identified. Their clearing points increase with increasing the perfluorocarbon chain length, while decrease with increasing the alkoxy chain length. Comparison o

Full text of DOI:10.1080/15421406.2020.1811015

Molecular Crystals and Liquid Crystals
ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/gmcl20
Liquid crystalline behaviors of three series of
hockey stick-like compounds
Gege Jin, Yongmin Guo, Limin Wu, Yi Li, Baozong Li & Yonggang Yang
To cite this article: Gege Jin, Yongmin Guo, Limin Wu, Yi Li, Baozong Li & Yonggang Yang (2020)
Liquid crystalline behaviors of three series of hockey stick-like compounds, Molecular Crystals and
Liquid Crystals, 709:1, 1-13, DOI: 10.1080/15421406.2020.1811015
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MOLECULAR CRYSTALS AND LIQUID CRYSTALS
2020, VOL. 709, NO. 1, 1–13
https://doi.org/10.1080/15421406.2020.1811015
Liquid crystalline behaviors of three series of hockey
stick-like compounds
Gege Jina, Yongmin Guoa, Limin Wub, Yi Lia, Baozong Lia, and Yonggang Yanga
aJiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of
Polymer Science and Engineering, State and Local Joint Engineering Laboratory for Novel Functional
Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow
b
University, Suzhou, P. R. China; School of Environmental Science and Engineering, Yancheng Institute
of Technology, Yancheng, Jiangsu Province, P. R. China
KEYWORDS
ABSTRACT
Ester; lateral substitution;
liquid crystal; perfluoroalkyl
Three series of meta-perfluoroalkylphenol esters are synthesized.
Both SmA and SmC phases are identified. Their clearing points
increase with increasing the perfluorocarbon chain length, while
decrease with increasing the alkoxy chain length. Comparison of the
3-tridecafluorohexylbenzoates and 3-tridecafluorohexylphenol esters,
the 3-tridecafluorohexylbenzoates show higher clearing points, indi-
cating that the direction of the ester bond plays an important role
in the thermostability of the liquid crystalline phases. Moreover, it
was proposed that the compounds with short and long alkoxy
chains packed into different structures.
Introduction
Liquid crystals with varieties of geometric structures, such as rod-like, bowl-shaped,
banana-shaped, T-shaped have been developed. Among these structures, rod-like liquid
crystals have been well-studied. For the liquid crystals with perfluoroalkyl and semi-per-
fluoroalkyl chains, most of them are rod-like molecules with fluorocarbon chains at the
terminals [1–14]. Due to the fluorophilic association of the fluoroalkyl chains, smectic
phases are feasible to be formed. With the introduction of chiral center, liquid crystals
ꢀ
with wide temperature range of the SmC phase can be obtained. Up to now, the
reports on liquid crystals with lateral fluorocarbon chains are few [15–19]. T-shaped
molecules with lateral fluorocarbon chains can organize into varieties of liquid crystal-
line phase [15–18]. Meta-perfluoroalkyl benzoates exhibit SmA, SmC, and SmB phases
[19]. Herein, three series of hockey stick-like meta-perfluoroalkyl phenol esters were
synthesized. Enantiotropic SmC phase preferred to be formed.
Results and discussion
The compounds, F6OBPn, F8OBPn, and F10OBPn, were synthesized according to the
route depicted in Scheme 1. The phase transition behavior of the final compounds is
CONTACT Y. Yang
ygyang@suda.edu.cn; B. Li
libaozong@suda.edu.cn
Jiangsu Key Laboratory of Advanced
Functional Polymer Design and Application, Department of Polymer Science and Engineering, State and Local Joint
Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and
Materials Science, Soochow University, Suzhou 215123, P. R. China.
ß 2020 Taylor & Francis Group, LLC

2
G. JIN ET AL.
Scheme 1. Synthetic route of the compounds FmOBPn and molecular structures of FmCBPn.
summarized in Table 1, which is mainly determined with differential scanning calorim-
etry (DSC). Since the enthalpies of the SmA-SmC and SmC-SmA transitions are low,
the transition temperatures of them are failed to be obtained using DSC. Therefore, few
data are obtained from polarizing optical microscopy (POM) characterization.
Moreover, since the temperature ranges of the SmA phases of F6OBP4 and F8OBP4
are narrow, few date are also obtained from POM characterization. Figure 1 plots the
transition temperatures of the compounds, F6OBPn, F8OBPn, and F10OBPn, as a
function of the number of methylene units (n) in the alkoxy chain. Only smectic phases
were identified. For compounds F6OBPn, enantiotropic SmC phase prefers to be
formed (Fig. 1a). F6OBP4 shows enantiotropic SmA and SmC phases and a monotropic
CrE phase. The fan-shaped texture, broken fan-shaped one and fan-shaped one with
arcs were identified in the POM images (Fig. 2). The others show only an enantiotropic
SmC phase. The clearing points of this series show somewhat odd–even effect.
Comparison of compounds F6OBPn and F6CBPn, when the carbon number is same,
the clearing point of F6CBPn is about 30K higher than that of F6OBPn (Scheme 1 and
Fig. 1d). This phenomenon is proposed to be driven by the molecular polarity.
For compounds F8OBPn, F8OBP4 shows both enantiotropic SmA and SmC phases,
and F8OBP10 and F8OBP12 show only a monotropic SmC phase (Fig. 1b). The others
show only an enantiotropic SmC phase. The clearing points also show somewhat odd–-
even effect. For compounds F10OBPn, F10OBP7 shows a monotropic SmC phase, and
the liquid crystalline behavior of F10OBP12 could not be found due to recrystallization
(Fig. 1c). The others are liquid crystals with an enantiotropic SmC phase. Comparison
of these three series, with increasing the fluorocarbon chain length, both the melting
point and clearing point are increased. However, the temperature range of the SmC
phase becomes narrower. With increasing the length of the alkoxy chain, the clearing
points decrease gradually, SmA phase is suppressed and SmC phase tends to be formed.
The phase transition behavior of compounds F6CBP8, F8CBP8, and F10CBP8 has
been reported previously [19]. With increasing the fluorocarbon chain length, the clear-
ing points increase gradually, and SmC phase is suppressed (Fig. 3). Comparison of the
compounds shown in Fig. 3, the 3-perfluoroalkylbenzoates show higher melting points
and clearing points. The direction of the ester bond plays an important role in the mes-
ophase structure, melting point and clearing point. A similar phenomenon has been
reported previously [20].
The mesophases of the liquid crystals were further confirmed by characterizing using
small angle X-ray scattering (SAXS) (Fig. 4). For F6OBP4, the layer thicknesses are

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
3
Table 1. Transition temperatures of the compounds.
Compound
n
Transition temperature (ꢁC)/ [DH] (kJ molꢂ1
)
F6OBP4
F6OBP5
F6OBP6
F6OBP7
F6OBP8
F6OBP9
F6OBP10
F6OBP12
F8OBP4
F8OBP5
F8OBP6
F8OBP7
F8OBP8
F8OBP9
F8OBP10
F8OBP12
F10OBP4
F10OBP5
F10OBP6
F10OBP7
F10OBP8
F10OBP9
F10OBP10
F10OBP12
4
5
6
7
8
9
10
12
4
5
6
7
8
Cr 105.4 [ꢂ16.49] SmC 142.9a SmA 148.5a I 148.3a SmA 142.7a SmC 98.9a CrE 82.9 [13.04] Cr
Cr 97.0 [ꢂ15.58] SmC 134.1 [ꢂ11.05] I 129.9 [10.81] SmC 78.3 [14.17] Recr
Cr 84.5 [ꢂ14.09] SmC 127.7 [ꢂ10.70] I 123.1 [11.13] SmC 60.7 [17.79] Recr
Cr 94.6 [ꢂ24.94] SmC 115.3 [ꢂ9.27] I 111.5 [10.68] SmC 48.0 [16.03] Recr
Cr 78.7 [ꢂ21.65] SmC 108.8 [ꢂ9.04] I 103.3 [10.27] SmC 42.7 [17.67] Recr
Cr 93.0 [ꢂ20.23] SmC 101.7 [ꢂ5.11] I 97.6 [11.07] SmC 66.9 [25.41] Recr
Cr 94.7 [ꢂ40.46] SmC 96.8 [ꢂ1.95] I 93.0 [10.00] SmC 76.5 [30.13] Recr
Cr 88.8 [ꢂ0.65] SmC 91.3 [ꢂ38.97] I 84.1 [8.64] SmC 76.6 [25.69] Recr
Cr 128.5 [ꢂ19.73] SmC 157.7a SmA 159.8a I 159.6a SmA 157.5a SmC 98.1 [17.41] Recr
Cr 100.1 [ꢂ16.26] SmC 146.2 [ꢂ11.87] I 142.4 [16.78] SmC 66.8 [12.40] Recr
Cr 117.2 [ꢂ28.16] SmC 137.8 [ꢂ10.03] I 133.8 [15.19] SmC 74.0 [13.89] Recr
Cr 120.9 [ꢂ37.73] SmC 128.4 [ꢂ10.38] I 124.5 [14.85] SmC 71.7 [32.99] Recr
Cr 102.2 [ꢂ32.46] SmC 121.8 [ꢂ10.83] I 118.1 [12.07] SmC 77.2 [18.48] Recr
Cr 103.7 [ꢂ31.07] SmC 115.2 [ꢂ9.83] I 111.2 [13.29] SmC 81.2 [26.78] Recr
Cr 109.4 [ꢂ46.24] I 106.0 [10.84] SmC 88.1 [32.10] Recr
9
10
12
4
5
6
7
8
9
10
12
Cr 103.2 [ꢂ36.53] I 98.2 [10.33] SmC 88.5 [25.21] Recr
Cr 152.5 [ꢂ28.37] SmC 161.7 [ꢂ9.06] I 158.3 [13.79] SmC 127.0 [25.21] Recr
Cr 140.0 [ꢂ47.38] SmC 152.6 [ꢂ9.46] I 148.8 [11.49] SmC 107.3 [21.43] Recr
Cr 141.0 [ꢂ22.02] SmC 145.9 [ꢂ2.68] I 141.7 [14.59] SmC 106.8 [34.38] Recr
Cr 141.6 [ꢂ56.46] I 134.4 [12.51] SmC 106.7 [36.26] Recr
Cr 117.5 [ꢂ27.08] SmC 132.4 [ꢂ11.20] I 128.9 [11.35] SmC 109.3 [26.11] Recr
Cr 115.4 [ꢂ22.87] SmC 127.4 [ꢂ10.12] I 122.7 [12.58] SmC 107.0 [24.47] Recr
Cr 121.0 [ꢂ2.33] SmC 122.4 [ꢂ39.09] I 117.7 [8.35] SmC 112.7 [25.04] Recr
Cr 120.8 [ꢂ46.75] I 113.8 [48.21] Recr
Cr ¼ crystal; SmC ¼ smectic C; SmA ¼ smectic A; I ¼ isotropic liquid; CrE ¼ crystal E; Recr ¼ Recrystal.
aThe data are obtained from POM characterization, and corresponding enthalpies, DH in kJ molꢂ1 detected on the
second temperature run at a rate of 10 ꢁC minꢂ1
.
2.96, 2.94, and 3.11 nm at the SmA, SmC, and CrE mesophases, respectively. For the
CrE mesophase, three peaks were identified at 3.11, 2.20, and 1.56 nm with a 1/d ratio
of 1:ͱ\bar2:2. For the SAXS pattern of F6OBP6 taken at 110 ꢁC, two peaks were identi-
fied at 2.91 and 1.46 nm, indicating a SmC mesophase. The layer thicknesses of the
SmC mesophases of F6OBP4 and F6OBP6 were similar. However, for the SAXS pattern
of F6OBP9 taken at 95 ꢁC, one peak was identified at 3.16 nm. Similar phenomenon
was also identified in the series of F8OBPn. The layer thicknesses of the SmC meso-
phases of F8OBP4 and F8OBP6 were 3.22 and 3.21 nm, respectively. However, layer
thickness of the SmC mesophases of F8OBP9 was 3.32 nm. Moreover, for the SAXS pat-
tern of F10OBP4 taken at 155 ꢁC, one peak was identified at 3.65 nm, indicating a SmC
mesophase with a layer thickness of 3.65 nm.
For the compounds F6OBP7, F8OBP7, and F10OBP7, comparison with their neigh-
bors, the temperature ranges of their liquid crystalline phases are the narrowest. The
molecular packing structures of the compounds shown in Table 1 seem to be different
with increasing the alkoxy chain length. SAXS patterns of the compounds F10OBP6
and F10OBP9 were taken after being cooling down to 140 and 120 ꢁC, respectively (Fig.
3). SmC phases were formed at these temperatures. Although the alkoxy chain lengths
of the compounds F10OBP6 and F10OBP9 are different, the first scattering peaks of
them are almost identical. Therefore, the molecular packing structures of them are pro-
posed to be different [2,21,22]. The calculated molecular lengths of the compounds
F10OBP6 and F10OBP9 are 3.68 and 4.01 nm, respectively. Since they are longer than
the layer thickness, the molecules should show bent conformations and tilt within the
layers. For the compound F10OBP6, neighboring molecules are proposed to organize

4
G. JIN ET AL.
Figure 1. Transition behavior of the compounds (a) F6OBPn, (b) F8OBPn and (c) F10OBPn in the
heating process: dependence of the transition temperatures on the number (n) of methylene units of
the non-fluorinated chain; (d) the clearing points of F6OBPn and F6CBPn.
Figure 2. POM images of F6OBP4 taken during the cooling process. (a) The fan-shaped SmA texture
taken at 148.0 ꢁC; (b) broken fan-shaped SmC texture taken at 130.0 ꢁC; (c) fan-shaped CrE texture
with arcs taken at 85.0 ꢁC.
antiparallel (Fig. 5a). The mainly driven forces should be the dipolar interactions
between the antiparallel carbonyl groups. For the compound F10OBP9, the molecules
are proposed to organize in quasi-parallel (Fig. 5b) [21]. The hydrophobic association of
hydrocarbon chains, the fluorophilic association of the fluorocarbon chains and the
p-p/C–H … p interactions between neighboring aromatic rings should be the driven
forces for the formation of this structure.

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
5
Figure 3. Transition behavior of the compounds F6OBP8, F8OBP8, F10OBP8, F6CBP8, F8CBP8, and
F10CBP8 in the heating process.
Conclusion
Three series of hockey stick-like compounds with perfluoroalkyl chains were synthe-
sized. Most of them show an enantiotropic SmC phase. The clearing points decrease
with increasing the alkoxy chain length and increase with increasing the perfluoroalkyl
chain length. Both the liquid crystalline behavior and SAXS characterization suggested
that the alkoxy chain length played an important role in the molecular packing struc-
ture at the SmC phase.
Experimental
Characterization
FT-IR spectra were performed on a VERTEX 70 spectrometer at 4 cmꢂ1 resolution by
1
averaging over 16 scans. The H NMR spectra were taken on an INOVA-400 spectrom-
eter in DMSO-d6 or CDCl3 using tetramethylsilane (TMS) as an internal standard at
room temperature. Elemental analysis was measured on a Vario EL III instrument. DSC
measurements were conducted on a DSC 2010 under nitrogen at 10 ꢁC minꢂ1. Mass
spectra (MS) were measured with Ultraflextreme MALDI TOF/TOF spectroscope. The
POM images of the target compounds were taken using a CPV-900C polarization
microscope fitted with a Linkam LTS420 hot stage. The transition temperatures
reported in this paper were the peak values of the transition on DSC traces. Few of
them were the values obtained using POM. SAXS patterns were taken using an X-ray
scattering instrument (SAXSess mc2, Anton Paar) equipped with line collimation and a
2200 W sealed-tube X-ray generator (Cu-Ka, k ¼ 0.154 nm).
Chemicals
Dimethyl sulfoxide (DMSO) was obtained by distillation under reduced pressure.
Tetrahydrofuran (THF) was distilled from sodium benzophenone ketyl in an atmos-
phere of nitrogen. Dicyclohexylcarbodiimde (DCC) was purchased from Shanghai

6
G. JIN ET AL.
Figure 4. SAXS patterns of some liquid crystals taken at the different temperatures during the cooling
process.
Aladdin Biotech Co., Ltd. (China). 4-Dimethylaminopyridine (DMAP) was purchased
from Adamas Reagent Co., Ltd. (China). All other chemicals were purchased from
Sinopharm Group Chemical Reagent Co., Ltd. (China) and used as received without
further purification. 4-n-Alkoxybiphenyl-40-carboxylic acids were synthesized according
to the literature [23].
Synthesis
Synthesis of 3-perfluorohexylphenol
A typical synthetic procedure for the phenols was shown as following. To a suspension
of 3-iodophenol (10 g, 45.5 mmol) and Cu powder (8.6 g, 136.4 mmol) in anhydrous

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
7
Figure 5. Simulated molecular packing structures of (a) F10OBP6 and (b) F10OBP9.
DMSO (150.0 mL), perfluorohexyl iodide (24.3 g, 54.6 mmol) was added under N2 and
the mixture was stirred at 110 ꢁC for 3 h. Precipitate was removed by filtration and
washed with ether. After the addition of H2O, the aqueous layer was extracted with
ether. The combined layers were washed with H2O and brine, and dried with anhydrous
Na2SO4. After being filtered and concentrated, the residue was purified by column chro-
matography on silica gel (hexane/EtOAc, 10:1) to give product as a colorless oil; yield:
1
11.4 g (60.8%). FT-IR tmax: 3397, 1199, 1142, and 849 cmꢂ1. H NMR dH (400 MHz;
DMSO-d6; TMS): 6.99 (s, 1H, ArH), 7.08 (t, J ¼ 8.1 Hz, 2H, ArH), 7.43 (t, J ¼ 7.9 Hz,
1H, ArH), 10.13 (s, 1H, OH) ppm. MS m/z (rel. int.): 412 (Mþ, 100).
Characterization of 3-perfluorooctylphenol
Yield: 12.3 g (52.8%). FT-IR tmax: 3393, 1196, 1139 and 850 cmꢂ1 1H NMR dH
.
(400 MHz; DMSO-d6; TMS): 6.98 (s, 1H, ArH), 7.09 (t, J ¼ 8.1 Hz, 2H, ArH), 7.43 (t,
J ¼ 7.8 Hz, 1H, ArH), 9.77 (s, 1H, OH) ppm. MS m/z (rel. int.): 512 (Mþ, 100).
Characterization of 3-perfluorodecylphenol
Yield: 13.6 g (48.8%). FT-IR tmax: 3400, 1197, 1145, and 846 cmꢂ1 1H NMR dH
.
(400 MHz; DMSO-d6; TMS): 6.97 (s, 1H, ArH), 7.09 (t, J ¼ 8.0 Hz, 2H, ArH), 7.42 (t,
J ¼ 7.9 Hz, 1H, ArH), 9.37 (s, 1H, OH) ppm. MS m/z (rel. int.): 612 (Mþ, 100).
Synthesis of F6OBP4
A typical synthetic procedure for the final compounds was shown as following. 4-n-
Butoxybiphenyl-40-carboxylic acid (67.5 mg, 0.25 mmol), 3-perfluorohexylphenol
(103 mg, 0.25 mmol), DCC (57.7 mg, 0.28 mmol), catalytic DMAP and dry THF (20 ml)
were stirred under N2 at room temperature for 12 h. The mixture was filtered and the
residue was washed with THF. The collected filtrates were evaporated on a rotary evap-
orator. The residue was recrystallized from acetone/methanol for two times to give
89 mg of white solid; yield 53.6%. FT-IR tmax: 2933, 2872, 1739, 1602, 1500, 1191, 1139,
1
and 826 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.95–1.87 (m, 7H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,

8
G. JIN ET AL.
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 687(MþþNa, 100),
253(C4H9OC6H4C6H4COþ, 0.54). Elemental analysis: calculated (for C29H21F13O3), C
52.42, H 3.19%; found, C 52.71, H 3.49%.
Characterization of F6OBP5
Yield: 95.0 mg (56.0%). FT-IR tmax: 2954, 2866, 1732, 1603, 1498, 1192, 1135, and
1
833 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.91–1.89 (m, 9H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 701(MþþNa, 100),
267(C5H11OC6H4C6H4COþ, 0.72). Elemental analysis: calculated (for C30H23F13O3), C
53.11, H 3.42%; found, C 53.37, H 3.56%.
Characterization of F6OBP6
Yield: 91.1 mg (52.7%). FT-IR tmax: 2935, 2857, 1731, 1600, 1496, 1189, 1137, and
1
823 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.89–1.87 (m, 11H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 715(MþþNa, 100),
281(C6H13OC6H4C6H4COþ, 0.68). Elemental analysis: calculated (for C31H25F13O3), C
53.77, H 3.64%; found, C 54.00, H 3.83%.
Characterization of F6OBP7
Yield: 97.7 mg (55.4%). FT-IR tmax: 2929, 2854, 1731, 1602, 1498, 1194, 1136, and
1
824 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.87–1.88 (m, 13H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 729(MþþNa, 100),
295(C7H15OC6H4C6H4COþ, 0.72). Elemental analysis: calculated (for C32H27F13O3), C
54.40, H 3.85%; found, C 54.46, H 3.96%.
Characterization of F6OBP8
Yield: 100.7 mg (55.9%). FT-IR tmax: 2919, 2852, 1738, 1604, 1496, 1198, 1137 and
1
831 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.87-1.88 (m, 15H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 743(MþþNa, 100),
309(C8H17OC6H4C6H4COþ, 0.77). Elemental analysis: calculated (for C33H29F13O3), C
55.01, H 4.06%; found, C 55.31, H 3.35%.

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
9
Characterization of F6OBP9
Yield: 92.9 mg (50.6%). FT-IR tmax: 2920, 2848, 1738, 1602, 1495, 1196, 1141, and
1
834 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 17H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 757(MþþNa, 100),
323(C9H19OC6H4C6H4COþ, 0.70). Elemental analysis: calculated (for C34H31F13O3), C
55.59, H 4.25%; found, C 55.89, H 4.43%.
Characterization of F6OBP10
Yield: 97.2 mg (52.0%). FT-IR tmax: 2917, 2850, 1737, 1603, 1495, 1194, 1146, and
1
833 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 19H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 771(MþþNa, 100),
337(C10H21OC6H4C6H4COþ, 0.61). Elemental analysis: calculated (for C35H33F13O3), C
56.15, H 4.44%; found, C 56.43, H 4.70%.
Characterization of F6OBP12
Yield: 99.8 mg (51.4%). FT-IR tmax: 2918, 2848, 1738, 1604, 1495, 1196, 1142, and
1
829 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.85–1.87 (m, 23H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.3 Hz, 2H, ArH), 7.52 (d,
J ¼ 10.1 Hz, 3H, ArH), 7.60 (t, J ¼ 7.7 Hz, 3H, ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24
(d, J ¼ 8.0 Hz, 2H, ArH) ppm. MS m/z (rel. int.): 799(MþþNa, 100),
365(C12H25OC6H4C6H4COþ, 0.68). Elemental analysis: calculated (for C37H37F13O3), C
57.22, H 4.80%; found, C 57.33, H 4.90%.
Characterization of F8OBP4
Yield: 108.5 mg (56.8%). FT-IR tmax: 2937, 2868, 1731, 1604, 1495, 1194, 1144 and
1
827 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.96-1.87 (m, 7H, aliphatic hydrogens),
4.03 (t, J ¼ 5.8 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.0 Hz, 2H, ArH), 7.50 (s, 1H, ArH), 7.52
(d, J ¼ 9.9 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.8 Hz, 2H, ArH),
7.71 (d, J ¼ 7.7 Hz, 2H, ArH), 8.24 (d, J ¼ 7.7 Hz, 2H, ArH) ppm. MS m/z (rel. int.):
787(MþþNa, 100), 253(C4H9OC6H4C6H4COþ, 0.72). Elemental analysis: calculated (for
C31H21F17O3), C 48.70, H 2.77%; found, C 48.72, H 3.08%.
Characterization of F8OBP5
Yield: 106.8 mg (54.9%). FT-IR tmax: 2938, 2858, 1730, 1602, 1495, 1195, 1143 and
1
825 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.91-1.89 (m, 9H, aliphatic hydrogens),
4.02 (t, J ¼ 5.9 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.0 Hz, 2H, ArH), 7.50 (s, 1H, ArH), 7.52
(d, J ¼ 9.7 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.8 Hz, 2H, ArH),
7.71 (d, J ¼ 7.6 Hz, 2H, ArH), 8.24 (d, J ¼ 7.7 Hz, 2H, ArH) ppm. MS m/z (rel. int.):
801(MþþNa, 100), 267(C5H11OC6H4C6H4COþ, 0.76). Elemental analysis: calculated (for
C32H23F17O3), C 49.37, H 2.98%; found, C 49.82, H 3.42%.

10
G. JIN ET AL.
Characterization of F8OBP6
Yield: 105.7 mg (53.4%). FT-IR tmax: 2936, 2858, 1731, 1603, 1497, 1197, 1146, and
1
827 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.89–1.87 (m, 11H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.6 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.4 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 815(MþþNa, 100), 281(C6H13OC6H4C6H4COþ, 0.84). Elemental analysis: calcu-
lated (for C33H25F17O3), C 50.01, H 3.18%; found, C 50.51, H 3.54%.
Characterization of F8OBP7
Yield: 109.9 mg (54.5%). FT-IR tmax: 2916, 2851, 1737, 1603, 1496, 1195, 1145, and
1
834 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 13H, aliphatic hydro-
gens), 4.01 (t, J ¼ 6.1 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.2 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.6 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 8.0 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.0 Hz, 2H, ArH), 8.24 (d, J ¼ 7.9 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 829(MþþNa, 100), 295(C7H15OC6H4C6H4COþ, 0.72). Elemental analysis: calcu-
lated (for C33H25F17O3), C 50.63, H 3.37%; found, C 50.41, H 3.59%.
Characterization of F8OBP8
Yield: 115.4 mg (56.3%). FT-IR tmax: 2916, 2849, 1739, 1601, 1497, 1192, 1146, and
1
829 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 15H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.0 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.2 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.4 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.8 Hz, 2H,
ArH), 7.71 (d, J ¼ 7.8 Hz, 2H, ArH), 8.24 (d, J ¼ 7.7 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 843(MþþNa, 100), 309(C8H17OC6H4C6H4COþ, 0.76). Elemental analysis: calcu-
lated (for C33H25F17O3), C 51.23, H 3.56%; found, C 51.62, H 3.85%.
Characterization of F8OBP9
Yield: 111.0 mg (53.2%). FT-IR tmax: 2918, 2851, 1738, 1601, 1497, 1193, 1144, and
1
833 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 17H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.4 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.7 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.6 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.1 Hz, 2H, ArH), 8.24 (d, J ¼ 8.1 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 857(MþþNa, 100), 323(C9H19OC6H4C6H4COþ, 0.64). Elemental analysis: calcu-
lated (for C33H25F17O3), C 51.81, H 3.74%; found, C 51.62, H 4.02%.
Characterization of F8OBP10
Yield: 114.6 mg (54.1%). FT-IR tmax: 2916, 2849, 1740, 1602, 1496, 1193, 1146, and
1
835 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.86–1.87 (m, 19H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.1 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.1 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.5 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 7.8 Hz, 2H, ArH), 8.24 (d, J ¼ 7.7 Hz, 2H, ArH) ppm. MS m/z (rel.

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
11
int.): 871(MþþNa, 100), 337(C10H21OC6H4C6H4COþ, 0.73). Elemental analysis: calcu-
lated (for C33H25F17O3), C 52.37, H 3.92%; found, C 52.69, H 4.15%.
Characterization of F8OBP12
Yield: 115.5 mg (52.7%). FT-IR tmax: 2918, 2852, 1739, 1602, 1495, 1193, 1147, and
1
828 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.85–1.87 (m, 23H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.5 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.4 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.5 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 899(MþþNa, 100), 365(C12H25OC6H4C6H4COþ, 0.62). Elemental analysis: calcu-
lated (for C33H25F17O3), C 53.43, H 4.25%; found, C 53.86, H 4.53%.
Characterization of F10OBP4
Yield: 118.4 mg (54.8%). FT-IR tmax: 2936, 2868, 1731, 1604, 1497, 1195, 1148, and
1
825 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.97–1.86 (m, 7H, aliphatic hydro-
gens), 4.03 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.6 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.7 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.8 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 887(MþþNa, 100), 253(C4H9OC6H4C6H4COþ, 0.84). Elemental analysis: calculated
(for C33H21F21O3), C 45.85, H 2.45%; found, C 45.80, H 2.66%.
Characterization of F10OBP5
Yield: 114.9 mg (52.3%). FT-IR tmax: 2939, 2874, 1731, 1601, 1497, 1194, 1148, and
1
826 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.92–1.88 (m, 9H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.7 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.4 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.6 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 901(MþþNa, 100), 267(C5H11OC6H4C6H4COþ, 0.76). Elemental analysis: calcu-
lated (for C34H23F21O3), C 46.48, H 2.64%; found, C 46.41, H 3.00%.
Characterization of F10OBP6
Yield: 119.8 mg (53.7%). FT-IR tmax: 2938, 2859, 1729, 1601, 1495, 1194, 1145, and
1
826 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.89–1.87 (m, 11H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.6 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.6 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 915(MþþNa, 100), 281(C6H13OC6H4C6H4COþ, 0.63). Elemental analysis: calcu-
lated (for C35H25F21O3), C 47.10, H 2.82%; found, C 47.28, H 3.19%.
Characterization of F10OBP7
Yield: 119.5 mg (52.8%). FT-IR tmax: 2921, 2855, 1732, 1604, 1498, 1193, 1149, and
1
826 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.87–1.87 (m, 13H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.8 Hz, 2H, ArH), 7.50 (s, 1H, ArH),

12
G. JIN ET AL.
7.52 (d, J ¼ 10.5 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 8.4 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 929(MþþNa, 100), 295(C7H15OC6H4C6H4COþ, 0.72). Elemental analysis: calcu-
lated (for C31H21F17O3), C 47.69, H 3.00%; found, C 47.70, H 3.42%.
Characterization of F10OBP8
Yield: 124.9 mg (54.3%). FT-IR tmax: 2922, 2855, 1724, 1602, 1497, 1195, 1148, and
1
829 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.87–1.87 (m, 15H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.5 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.5 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 8.3 Hz, 2H,
ArH), 7.71 (d, J ¼ 7.9 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 943(MþþNa, 100), 309(C8H17OC6H4C6H4COþ, 0.62). Elemental analysis: calcu-
lated (for C31H21F17O3), C 48.27, H 3.18%; found, C 48.32, H 3.51%.
Characterization of F10OBP9
Yield: 120.6 mg (51.6%). FT-IR tmax: 2921, 2854, 1739, 1602, 1497, 1193, 1148, and
1
828 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.85–1.87 (m, 17H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.5 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.5 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 957(MþþNa, 100), 323(C9H19OC6H4C6H4COþ, 0.76). Elemental analysis: calcu-
lated (for C31H21F17O3), C 48.83, H 3.34%; found, C 49.16, H 3.72%.
Characterization of F10OBP10
Yield: 120.1 mg (50.7%). FT-IR tmax: 2923, 2851, 1734, 1605, 1497, 1191, 1148, and
1
828 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.84–1.87 (m, 19H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.4 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.5 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.3 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.1 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 971(MþþNa, 100), 337(C10H21OC6H4C6H4COþ, 0.74). Elemental analysis: calcu-
lated (for C31H21F17O3), C 49.38, H 3.51%; found, C 49.73, H 3.89%.
Characterization of F10OBP12
Yield: 123.7 mg (50.7%). FT-IR tmax: 2916, 2849, 1738, 1604, 1495, 1194, 1149, and
1
828 cmꢂ1. H NMR dH (400 MHz; CDCl3; TMS): 0.85–1.87 (m, 23H, aliphatic hydro-
gens), 4.02 (t, J ¼ 6.5 Hz, 2H, RCH2O), 7.01 (d, J ¼ 8.5 Hz, 2H, ArH), 7.50 (s, 1H, ArH),
7.52 (d, J ¼ 10.5 Hz, 2H, ArH), 7.60 (t, J ¼ 6.0 Hz, 1H, ArH), 7.61 (d, J ¼ 7.7 Hz, 2H,
ArH), 7.71 (d, J ¼ 8.2 Hz, 2H, ArH), 8.24 (d, J ¼ 8.2 Hz, 2H, ArH) ppm. MS m/z (rel.
int.): 999(MþþNa, 100), 365(C12H25OC6H4C6H4COþ, 0.68). Elemental analysis: calcu-
lated (for C31H21F17O3), C 50.42, H 3.82%; found, C 50.76, H 4.07%.

MOLECULAR CRYSTALS AND LIQUID CRYSTALS
13
Funding
This work was supported the Political Science-Preponderant Discipline of Jiangsu Province, the
Project of Scientific and Technologic Infrastructure of Suzhou (SZS201905) and the National
Natural Science Foundation of China (No. 51473141 and 21574095).
ORCID
Yonggang Yang
http://orcid.org/0000-0003-0185-7471
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