Mesomorphism behavior of two series of chiral compounds with semiperfluorocarbon chains

Article abstract of DOI:10.1080/15421406.2012.674466

Thermotropic liquid crystals with fluorocarbon chains have attracted much attention, because they are feasible to form smectic phases. Herein, two series of chiral compounds with semiperfluorocarbon chains were designed and synthesized. These compounds were characterized by IR, ¹H NMR, ¹⁹F NMR, mass spectroscopy, and elemental analysis. Phase transition behavior was investigated by differential scanning calorimetry and polarized optical microscopy. Members of the two-ring series do not exhibit liquid crystalline phases. However, the three-ring analogues exhibit an enantiotropic SmA phase. When the length of alkyl chains is sufficient, an enantiotropic SmB phase is also identified. Taylor and Francis Group, LLC.

Full text of DOI:10.1080/15421406.2012.674466

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Mesomorphism Behavior of Two
Series of Chiral Compounds with
Semiperfluorocarbon Chains
Jie Li a , Nan Zhao a , Yi Li a , Baozong Li a & Yonggang Yang a
a Key Laboratory of Organic Synthesis of Jiangsu Province, College of
Chemistry, College of Chemistry, Chemical Engineering and Materials
Science , Soochow University , Suzhou , P R China
Published online: 30 Jul 2012.
To cite this article: Jie Li , Nan Zhao , Yi Li , Baozong Li & Yonggang Yang (2012) Mesomorphism
Behavior of Two Series of Chiral Compounds with Semiperfluorocarbon Chains, Molecular Crystals and
Liquid Crystals, 562:1, 123-132, DOI: 10.1080/15421406.2012.674466
To link to this article: http://dx.doi.org/10.1080/15421406.2012.674466
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Mol. Cryst. Liq. Cryst., Vol. 562: pp. 123–132, 2012
Copyright © Taylor & Francis Group, LLC
ISSN: 1542-1406 print/1563-5287 online
DOI: 10.1080/15421406.2012.674466
Mesomorphism Behavior of Two Series of Chiral
Compounds with Semiperfluorocarbon Chains
JIE LI, NAN ZHAO, YI LI, BAOZONG LI,
AND YONGGANG YANG∗
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry,
College of Chemistry, Chemical Engineering and Materials Science, Soochow
University, Suzhou, P R China
Thermotropic liquid crystals with fluorocarbon chains have attracted much attention,
because they are feasible to form smectic phases. Herein, two series of chiral compounds
with semiperfluorocarbon chains were designed and synthesized. These compounds were
1
characterized by IR, H NMR, 19F NMR, mass spectroscopy, and elemental analysis.
Phase transition behavior was investigated by differential scanning calorimetry and
polarized optical microscopy. Members of the two-ring series do not exhibit liquid
crystalline phases. However, the three-ring analogues exhibit an enantiotropic SmA
phase. When the length of alkyl chains is sufficient, an enantiotropic SmB phase is also
identified.
Keywords: Chirality; liquid crystals; perfluorocarbon
Introduction
Liquid crystals with perfluoroalkyl and semiperfluoroalkyl chains attracted much attention
during the last decades [1–23]. Due to fluorophilic associations, smectic mesophases are
feasible to be formed. For diblock H(CH2)n(CF2)mF and triblock F(CF2)m(CH2)n(CF2)mF
molecules, they can melt into smectic B (SmB) or G mesophase [1, 2]. Generally, the ther-
mostability of the smectic phases increased with increasing the length of the fluorocarbon
chains [21]. It was also found that a change of the terminal hydrogen in the fluorocarbon
chain to chlorine could increase the clearing points of the liquid crystals [19–21]. Partic-
ularly, molecules with semiperfluorocarbon chains exhibit tilted smectic phases and some
of them are inherently ferroelectric [23].
Since liquid crystals with smectic C∗ (SmC∗) phase are potentially applied in ferro-
electric liquid crystal display mixtures, many kinds of chiral liquid crystals were designed
and synthesized. For the liquid crystals with both semifluoroalkyl chains and chiral centers,
they can also melt into SmC∗ phase [20–22]. Herein, base on previous results, two series
of chiral molecules with semifluoroalkyl chains were synthesized [22]. Only one series of
them exhibit enantiotropic smectic A (SmA) and SmB phases.
∗Address correspondence to Y. Yang, Key Laboratory of Organic Synthesis of Jiangsu Province,
College of Chemistry, College of Chemistry, Chemical Engineering and Materials Science, Soochow
University, Suzhou, 215123, P R China. Tel.: 00-86-512-65880047; Fax: 00-86-512-65882052.
E-mail: ygyang@suda.edu.cn
123

124
J. Li et al.
Results and Discussion
The synthesis of the target molecules containing a highly fluorinated tail chain (the 1,1,2,2-
tetrahydroperfluorodecanyl group) is outlined in the scheme according to the literatures
[21,22]. The one hydroxyl group of hydroquinone was protected with benzyl bromide
and the protected phenol occurred Mitsunbobu coupling reaction with L-methyl lactate.
Then the methyl ester was hydrolyzed to give the carboxylic acid, which was esterified
with the fluorinated alcohol using dicyclohexylcarbodiimide (DCC) as dehydrating agent
and N,N-dimethylaminopyridine (DMAP) as catalyst in dry tetrahydrofuran. The benzyl
ether produced was converted to the corresponding phenol ester by removal of the benzyl
protecting group which was achieved by stirring it at room temperature in an H2 atmosphere
in the presence of palladium on active carbon in ethyl acetate. The para-alkoxy benzoic
acid was prepared with the previously prepared protected phenol; it was esterified with
the previously prepared ester phenol 1 using the DCC/DMAP system. Details of synthetic
procedure for series An is shown in the scheme. Series Bn were also prepared through
similar procedure .
The phase transition temperatures of all the compounds were determined by DSC with
a heating rate of 5.0◦C min−1. The mesomorphic textures were observed on polarizing
optical textures for determining the types of mesophases. The transition temperatures of
the series An and Bn shown in the Table 1 are the maxima of the transition peaks on each
a)
b)
CH2O
O
COOCH3
HO
COOCH3
CH2O
O
COOH
c)
d)
CH2O
O
HO
O
COOCH2CH2(CF2)8F
COOCH2CH2(CF2)8F
1
e)
H(CH2)
O
n
COO
O
H(CH2)
O
COOH
COOCH2CH2(CF2)8F
+ 1
n
Series An
n = 4 - 12.
e)
H(CH2)
O
COO
COOH + 1
n
H(CH2)
O
COO
COO
O
COOCH2CH2(CF2)8F
n
n = 4 - 12.
Series Bn
H(CH2)
O
n
COO
O
COOCH2CH2(CF2)8F
n = 7 - 10.
Series Cn
Scheme 1. Synthetic procedure of series An and Bn, and molecular structures of series Cn. (a)
C6H5CH2OC6H4OH, DEAD/PPh3, CH2Cl2, 0◦C; (b) NaOH, C2H5OH/H2O; (c) HOCH2CH2(CF2)8F,
DCC/DMAP, THF, 0◦C to r.t.; (d) Pd/C, ethyl acetate; (e) DCC/DMAP, THF, 0◦C to r.t.

Chiral Liquid Crystals
125
Table 1. Transition temperatures of the compounds An and Bn (Cr = crystal; CrX =
crystal X; SmA = smectic A phase; SmB = smectic B phase; I = isotropic liquid; Recr =
recrystallization)
Compound
n
Transition temperatures/◦C
A4
A5
A6
A7
A8
A9
A10
A11
A12
B4
4
5
6
7
8
Cr 96.8, I 90.3 Recr
Cr 100.3, I 95.5 Recr
Cr 97.5, I 92.7 Recr
Cr 98.5, I 93.4 Recr
Cr 98.9, I 92.3 Recr
Cr 97.5, I 94.0 Recr
Cr 99.6, I 93.6 Recr
Cr 98.8, I 93.8 Recr
9
10
11
12
4
5
6
7
8
9
Cr 99.4, I 95.7 Recr
Cr 113.0, SmA 200.3, I 198.5, SmA 91.1 Recr
Cr 112.5, SmA 196.1, I 193.8, SmA 98.6 Recr
Cr 113.2, SmA 203.5, I 201.2, SmA 100.0 Recr
Cr 114.4, SmA 198.4, I 197.0, SmA 105.3 Recr
Cr 120.0, SmA 195.5, I 194.1, SmA 104.9 Recr
Cr 112.1, SmB 121.0, SmA 186.8, I 185.6, SmA 120.0, SmB
105.0 Recr
B5
B6
B7
B8
B9
B10
B11
B12
10
11
12
Cr 115.6, SmB 136.8, SmA 184.5, I 182.8, SmA 136.5, SmB
107.2 Recr
Cr 113.6, CrX 119.8, SmB 141.9, SmA 178.6, I 176.0, SmA
141.2, SmB 110.4 Recr
Cr 117.8, SmB 145.6, SmA 176.5, I 175.4, SmA 145.3, SmB
111.8 Recr
DSC trace. For the series An, no mesophases were identified. The melting points of them
are about 100◦C. Generally, molecules with even number of methylene units (n) exhibit
higher melting points than those with odd ones, except A5. Figure 1 plots the transition
temperatures of the series Bn as a function of the number of methylene units (n) in the
Figure 1. Transition behavior of series Bn: dependence of the transition temperatures on the number
(n) of methylene units of the alkoxy chain.

126
J. Li et al.
nonfluorinated chain. All of these compounds exhibit smectic mesophases. The melting
points of them are about 110◦C–120◦C. When the number of methylene units (n) is smaller
than 9, only enantiotropic SmA phase is identified. When it is larger, both enantiotropic
SmA and SmB phases are identified. Generally, the clearing points of them decrease with
increasing alkoxy chain length.
It has been reported by us that the series Cn exhibited both enantiotropic SmA and
SmC∗ phases [22]. However, the series An are not liquid crystals. The phenyl group drives
the clear points of the series Cn about 100◦C higher than the melting points of the series
An. Compare the series Bn with Cn, there are no significant difference among their clearing
points. However, series Bn only exhibit enanotiotropic SmA and SmB phases. The bridged
–COO– group seems play an important role in the organization of the molecules. Although
the –COO– group decreases the stiffness of the molecules, it can increase the polarity and
the length/diameter ratio of them. Series Bn were proposed applied in the liquid crystal
display mixtures.
In summary, two series of chiral compounds with semifluorocarbon chains have been
synthesized. One series of them exhibit enantiotropic SmA and SmB phases. Generally,
the increase of the alkoxy chains’ length can decrease their clearing points. The addition of
phenyl rings in the core increases the clearing points; the addition of the –COO– group in
the core plays an important role in the organization of the molecules.
Experimental
Characterization
The structures of the final products and intermediates were determined by a variety of
spectral methods. FT-IR spectra were taken on a Nicolet 6700 spectrometer, using KBr
pellets of the solids. 1H NMR spectra, with TMS as internal NMR standard, were recorded
on a Varian NMR spectrometer (300 or 400 MHz); 19F NMR spectra, with trifluoroacetic
acid (TFA) as external standard, were recorded on a Varian NMR spectrometer (300 or
400 MHz). For the 19F NMR spectra spectrum the high field was negative. Mass spec-
tra (MS) were measured with MicroMass TOF-MS spectroscope. Field-emission electron
microscopy (FESEM) images were taken on a Hitachi S-4700. Elemental analyses were
performed on a Perkin Elmer series II CHNS/O analyzer 2400. The phase transition temper-
atures of the target compounds were measured by optical microscopy using a Leica DMRX
polarization microscope fitted with a Linkam LTS350 hot stage and CI94 temperature
controller and differential scanning calorimetry (DSC, TA Q-200 calorimeter with a data
system and heating and cooling rate of 5◦C min−1). The transition temperatures reported
in this paper were the peak values of the transition on DSC traces. Phase identification was
made by comparing the observed textures with those reported in the literature.
Synthesis
All of the final compounds were purified by column chromatography on silica gel using
petroleum ether (b.p. 60◦C–90◦C)/ethyl acetate (20:1) as eluant and then recrystallized
from acetone/methanol. The following were structural characterization of target molecules.
Synthesis of Compound A4. A typical synthetic procedure for Sereis An and Bn is shown
as following. 4-n-Butoxybenzoic acid (200 mg, 1.03 mmol), compound 1 (647 mg, 1.03
mmol), N,Nꢀ-dicyclohexylcarbodiimide (213 mg, 1.03 mmol), catalytic DMAP and dry

Chiral Liquid Crystals
127
THF (10 ml) were stirred under N2 at room temperature for 48 h. The mixture was filtered
and the residue was washed with THF. The collected filtrates were evaporated on a rotary
evaporator. The residue was purified by flash chromatography and recrystallized from
acetone/methanol to give 269 mg of white solid yield 32.5%. M.p. 96.8◦C. IR (KBr, cm−1):
2941, 2874, 1753, 1729, 1607, 1510, 1467, and 1198. 1H NMR (300 MHz, CDCl3, TMS):
δ (ppm) 0.99 (t, J = 7.4 Hz, 3H, –CH2CH3), 1.43–1.85 (m, 4H, aliphatic hydrogens). 1.63
(d, J = 6.9 Hz, 3H, –CHCH3), 2.48 (tt, J1 = 18 Hz, J2 = 6.3 Hz, 2H, –CH2Rf), 4.04 (t,
J = 6.5 Hz, 2H, –CH2CH2Rf), 4.47 (t, J = 6.5 Hz, 2H, –OCH2), 4.77 (q, J = 6.7 Hz,
1H, –CHCH3), 6.90 (d, J = 9.0 Hz, 2H, ArH), 6.95 (d, J = 9.0 Hz, 2H, ArH), 7.10 (d,
J = 9.0 Hz, 2H, ArH), 8.11 (d, J = 9.0 Hz, 2H, ArH). 19F NMR (300 MHz, CDCl3,
TFA): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s, 2F), −45.16 (s, 2F), (−44.39
to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz, 3F). MS m/z (rel. int.): 804
(M++1), 313 (C4H9O–C6H4–COO–C6H4–O–C+H–CH3, 4.0), 177 (C4H9–C6H4–CO+,
100), 121 (HO–C6H4–CO+, 30.0). Elemental analysis: calculated for C30H25O6F17, C
44.79, H 3.13%; found, C 45.28, H 3.02%.
Synthesis of Compound A5. M.p. 100.3◦C. IR (KBr, cm−1): 2942, 2871, 1753, 1729, 1607,
1511, 1468, and 1198. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.96 (t, J = 7.1 Hz, 3H,
–CH2CH3), 1.40–1.88 (m, 6H, aliphatic hydrogens). 1.64 (d, J = 6.9 Hz, 3H, –CHCH3),
2.49 (tt, J1 = 18.0 Hz, J2 = 6.5 Hz, 2H, –CH2Rf), 4.05 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.49 (t, J = 6.5 Hz, 2H, –OCH2), 4.78 (q, J = 6.6 Hz, 1H, –CHCH3), 6.91 (d, J = 9.3 Hz,
2H, ArH), 6.97 (d, J = 9.0 Hz, 2H, ArH), 7.11 (d, J = 9.0 Hz, 2H, ArH), 8.12 (d, J = 8.7 Hz,
2H, ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s,
2F), −45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 818 (M++1), 337 (C5H13O–C6H4–COO–C6H4–O–C+H–CH3, 4.0),
191 (C5H13–C6H4–CO+, 100), 121 (HO–C6H4-CO+, 15.8). Elemental analysis: calculated
for C31H27O6F17, C 45.49, H 3.32%; found, C 45.53, H 3.17%.
Synthesis of Compound A6. M.p. 97.5◦C. IR (KBr, cm−1): 2941, 2869, 1753, 1729, 1608,
1511, 1468, and 1198. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.93 (t, J = 7.1 Hz, 3H,
–CH2CH3), 1.23–1.88(m, 8H, aliphatic hydrogens). 1.65 (d, J = 6.9 Hz, 3H, –CHCH3),
2.50 (tt, J1 = 18.3 Hz, J2 = 6.5 Hz, 2H, –CH2Rf), 4.05 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.49 (t, J = 6.3 Hz, 2H, –OCH2), 4.79 (q, J = 6.8Hz, 1H, –CHCH3), 6.92 (d, J = 9.0 Hz,
2H, ArH), 6.97 (d, J = 9.0 Hz, 2H, ArH), 7.17 (d, J = 9.0 Hz, 2H, ArH), 8.13 (d, J = 8.7 Hz,
2H, ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s,
2F), −45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 832 (M++1), 341 (C6H13O–C6H4–COO–C6H4–O–C+H–CH3, 4.0),
205 (C6H13–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 34.2). Elemental analysis: calculated
for C32H29O6F17, C 46.16, H 3.51%; found, C 45.77, H 3.37%.
Synthesis of Compound A7. M.p. 98.5◦C. IR (KBr, cm−1): 2939, 2866, 1753, 1731, 1607,
1512, 1468, and 1198. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.91 (t, J = 6.8 Hz, 3H,
–CH2CH3), 1.33–1.88 (m, 10H, aliphatic hydrogens). 1.65 (d, J = 6.6 Hz, 3H, –CHCH3),
2.50 (tt, J1 = 18.3 Hz, J2 = 6.2 Hz, 2H, –CH2Rf), 4.05 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.49 (t, J = 6.5 Hz, 2H, –OCH2), 4.79 (q, J = 6.8 Hz, 1H, –CHCH3), 6.92 (d, J = 9.0 Hz, 2H,
ArH), 6.97 (d, J = 9.0 Hz, 2H, ArH), 7.12 (d, J = 9.0 Hz, 2H, ArH), 8.13 (d, J = 9.0 Hz, 2H,
ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s, 2F),
−45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz, 3F).
MS m/z (rel. int.): 846 (M++1), 355 (C7H15O–C6H4–COO–C6H4–O–C+H–CH3, 15.8),

128
J. Li et al.
219 (C7H15–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 57.5). Elemental analysis: calculated
for C33H31O6F17, C 46.82, H 3.69%; found, C 46.35, H 3.52%.
Synthesis of Compound A8. M.p. 98.9◦C. IR (KBr, cm−1): 2925, 2855, 1753, 1731, 1607,
1512, 1468, and 1198. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.89 (t, J = 5.1 Hz, 3H,
–CH2CH3), 1.30–1.85 (m, 12H, aliphatic hydrogens). 1.63 (d, J = 5.1 Hz, 3H, –CHCH3),
2.48 (tt, J1 = 13.5 Hz, J2 = 4.7 Hz, 2H, –CH2Rf), 4.04 (t, J = 4.8 Hz, 2H, –CH2CH2Rf),
4.48 (t, J = 4.7 Hz, 2H, –OCH2), 4.77 (q, J = 5.1 Hz, 1H, –CHCH3), 6.90 (d, J = 6.6 Hz,
2H, ArH), 6.96 (d, J = 6.9 Hz, 2H, ArH), 7.11 (d, J = 6.6 Hz, 2H, ArH), 8.11 (d, J = 6.6 Hz,
2H, ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s,
2F), −45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 860 (M++1), 369 (C8H17O–C6H4–COO–C6H4–O–C+H–CH3, 2.1),
233 (C8H17–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 30.0). Elemental analysis: calculated
for C34H33O6F17, C 47.45, H 3.87%; found, C 46.88, H 3.92%.
Synthesis of Compound A9. M.p. 97.5◦C. IR (KBr, cm−1): 2924, 2854, 1753, 1731, 1607,
1512, 1468, and 1199. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.89 (t, J = 6.6 Hz, 3H,
–CH2CH3), 1.25–1.86 (m, 14H, aliphatic hydrogens). 1.63 (d, J = 3.5 Hz, 3H, –CHCH3),
2.48 (tt, J1 = 18.3 Hz, J2 = 6.3 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.5 Hz, 2H, –CH2CH2Rf),
4.48 (t, J = 6.5 Hz, 2H, –OCH2), 4.77 (q, J = 6.8 Hz, 1H, –CHCH3), 6.90 (d, J = 9.3 Hz, 2H,
ArH), 6.96 (d, J = 9.0 Hz, 2H, ArH), 7.11 (d, J = 9.0 Hz, 2H, ArH), 8.11 (d, J = 9.0 Hz, 2H,
ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s, 2F),
−45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz, 3F).
MS m/z (rel. int.): 874 (M++1), 383 (C9H19O–C6H4–COO–C6H4–O–C+H–CH3, 2.5), 247
(C9H19O–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 33.3). Elemental analysis: calculated
for C35H35O6F17, C 48.06, H 4.03%; found, C 47.68, H 3.75%.
Synthesis of Compound A10. M.p. 99.6◦C. IR (KBr, cm−1): 2923, 2853, 1753, 1732, 1607,
1512, 1471, and 1199. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.89 (t, J = 6.6 Hz, 3H,
–CH2CH3), 1.23–1.85 (m, 16H, aliphatic hydrogens). 1.64 (d, J = 6.8 Hz, 3H, –CHCH3),
2.48 (tt, J1 = 18.0 Hz, J2 = 6.4 Hz, 2H, –CH2Rf), 4.04 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.48 (t, J = 6.2 Hz, 2H, –OCH2), 4.77 (q, J = 6.7Hz, 1H, –CHCH3), 6.90 (d, J = 9.2 Hz, 2H,
ArH), 6.96 (d, J = 8.8 Hz, 2H, ArH), 7.10 (d, J = 9.2 Hz, 2H, ArH), 8.11 (d, J = 8.8 Hz, 2H,
ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s, 2F),
−45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz, 3F).
MS m/z (rel. int.): 888 (M++1), 397 (C10H21O–C6H4–COO–C6H4–O–C+H–CH3,2.5), 261
(C10H21O–C6H4–CO+, 100), 121 (HO–C6H4-CO+, 27.5). Elemental analysis: calculated
for C36H37O6F17, C 48.66, H 4.20%; found, C 48.29, H 3.73%.
Synthesis of Compound A11. M.p. 98.8◦C. IR (KBr, cm−1): 2922, 2853, 1753, 1734, 1607,
1512, 1468, and 1200. 1H NMR (300 MHz, CDCl3, TMS): δ (ppm) 0.88 (t, J = 6.8 Hz, 3H,
–CH2CH3), 1.27–1.86 (m, 18H, aliphatic hydrogens). 1.63 (d, J = 6.9 Hz, 3H, –CHCH3),
2.48 (tt, J1 = 18.3 Hz, J2 = 6.5 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.48 (t, J = 6.3 Hz, 2H, –OCH2), 4.77 (q, J = 6.8 Hz, 1H, –CHCH3), 6.90 (d, J = 9.3 Hz,
2H, ArH), 6.95 (d, J = 9.0 Hz, 2H, ArH), 7.10 (d, J = 9.0 Hz, 2H, ArH), 8.11 (d, J = 9.0 Hz,
2H, ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s,
2F), −45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 902 (M++1), 411 (C11H23O–C6H4–COO–C6H4–O–C+H–CH3,

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2.5), 275 (C11H23O–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 10.8). Elemental analysis:
calculated for C37H39O6F17, C 49.23, H 4.35%; found, C 48.98, H 4.19%.
Synthesis of Compound A12. M.p. 99.4◦C. IR (KBr, cm−1): 2922, 2853, 1733, 1734, 1607,
1
1512, 1468, and 1200. H NMR (300 MHz, CDCl3), δ (ppm) 0.88 (t, J = 6.6 Hz, 3H,
–CH2CH3), 1.23–1.85 (m, 20H, aliphatic hydrogens). 1.63 (d, J = 6.8 Hz, 3H, –CHCH3),
2.49 (tt, J1 = 18 Hz, J2 = 6.4 Hz 2H, –CH2Rf), 4.04 (t, J = 6.6 Hz, 2H, –CH2CH2Rf), 4.48
(t, J = 6.4 Hz, 2H, –OCH2), 4.77 (q, J = 6.8 Hz, 1H, –CHCH3), 6.90 (d, J = 9.2 Hz, 2H,
ArH), 6.95 (d, J = 8.8 Hz, 2H, ArH), 7.10 (d, J = 9.2 Hz, 2H, ArH), 8.11 (d, J = 8.8 Hz,
2H, ArH). 19F NMR (300 MHz, CDCl3): δ (ppm) −48.56 (t, J = 12.27 Hz, 2F), −45.98 (s,
2F), −45.16 (s, 2F), (−44.39 to −44.12) (m, 6F), −36.01 (m, 2F), −3.16 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 916 (M++1), 425 (–C6H4–COO–C6H4–O–C+H–CH3, 1.1), 289
(C12H25–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 14.2). Elemental analysis: calculated for
C38H41O6F17, C 49.79, H 4.51%; found, C 50.13, H 4.51%.
Synthesis of Compound B4. M.p. 113.0◦C. IR (KBr, cm−1): 2958, 2872, 1753, 1736, 1605,
1510, 1414, and 1198. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.98 (t, J = 7.8 Hz, 3H,
–CH2CH3), 1.45–1.84 (m, 4H, aliphatic hydrogens), 1.62 (d, J = 6.8 Hz, 3H, –CHCH3),
2.47 (tt, J1 = 18 Hz, J2 = 6.4 Hz, 2H, –CH2Rf), 4.04 (t, J = 6.4 Hz, 2H, –CH2CH2Rf),
4.47 (t, J = 6.2 Hz, 2H, –OCH2), 4.76 (q, J = 6.5 Hz, 1H, –CHCH3), 6.90 (d, J = 9.2 Hz,
2H, ArH), 6.97 (d, J = 8.8 Hz, 2H, ArH), 7.11 (d, J = 8.8 Hz, 2H, ArH), 7.34 (d, J =
8.8 Hz, 2H, ArH), 8.13 (d, J = 8.8 Hz, 2H, ArH), 8.24 (d, J = 8.8 Hz, 2H, ArH). 19F
NMR (400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s,
2F), (−43.81–−44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.
int.): 924 (M++1),297 (C4H9O–C6H4–COO–C6H4–CO+, 20), 177 (C4H9O–C6H4–CO+,
100), 121 (HO–C6H4-CO+,15). Elemental analysis: calculated for C37H29O8F17, C 48.06,
H 3.16%; found, C 47.30, H 3.30%.
Synthesis of Compound B5. M.p. 112.5◦C. IR (KBr, cm−1), 2937, 2871, 1753, 1736, 1606,
1511, 1415, and 1199. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.93 (t, J = 6.8 Hz, 3H,
–CH2CH3), 1.34–1.87 (m, 6H, aliphatic hydrogens). 1.62 (d, J = 6.8 Hz, 3H, –CHCH3),
2.47 (tt, J1 = 19.8 Hz, J2 = 6.8 Hz, 2H, –CH2Rf), 4.04 (t, J = 6.4 Hz, 2H, –CH2CH2Rf),
4.47 (t, J = 6.4 Hz, 2H, –OCH2), 4.76 (q, J = 6.6 Hz, 1H, –CHCH3), 6.90 (d, J = 6.8 Hz,
2H, ArH), 6.97 (d, J = 8.0 Hz, 2H, ArH), 7.11 (d, J = 8.8 Hz, 2H, ArH), 7.34 (d, J =
8.4 Hz, 2H, ArH), 8.13 (d, J = 8.0 Hz, 2H, ArH), 8.24 (d, J = 8.0 Hz, 2H, ArH). 19F NMR
(400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s, 2F),
(−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.
int.): 938 (M++1), 311 (C5H11O–C6H4–COO–C6H4–CO+, 16), 191 (C5H11O–C6H4–CO+,
100), 121 (HO–C6H4–CO+, 20). Elemental analysis: calculated for C38H31O8F17, C 48.63,
H 3.33%; found, C 48.73, H 4.57%.
Synthesis of Compound B6. M.p. 113.2◦C. IR (KBr, cm−1), 2938, 2872, 1752, 1736, 1606,
1511, 1416, and 1199. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.90 (t, J = 6.8 Hz, 3H,
–CH2CH3), 1.26–1.86 (m, 8H, aliphatic hydrogens). 1.62 (d, J = 6.8 Hz, 3H, –CHCH3),
2.47 (tt, J1 = 18.2 Hz, J2 = 6.0 Hz, 2H, –CH2Rf), 4.04 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.47 (t, J = 6.2 Hz, 2H, –OCH2), 4.76 (q, J = 6.5 Hz, 1H, –CHCH3), 6.90 (d, J = 8.8 Hz,
2H, ArH), 6.97 (d, J = 8.8 Hz, 2H, ArH), 7.11 (d, J = 8.8 Hz, 2H, ArH), 7.34 (d, J =
8.8 Hz, 2H, ArH), 8.13 (d, J = 8.8 Hz, 2H, ArH), 8.24 (d, J = 8.8 Hz, 2H, ArH). 19F NMR
(400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s, 2F),

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(−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.
int.): 952 (M++1), 325 (C6H13O–C6H4–COO–C6H4–CO+, 22), 205 (C6H13O–C6H4–CO+,
100), 121 (HO–C6H4–CO+, 30). Elemental analysis: calculated for C39H33O8F17, C 49.17,
H 3.49%; found, C 48.61, H 3.55%.
Synthesis of Compound B7. M.p. 114.4◦C. IR (KBr, cm−1), 2925, 2855, 1753, 1737, 1606,
1511, 1415, and 1197. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.88 (t, J = 7.8 Hz, 3H,
–CH2CH3), 1.25–1.89 (m, 10H, aliphatic hydrogens). 1.62 (d, J = 6.8 Hz, 3H, –CHCH3),
2.47 (tt, J1 = 18.2 Hz, J2 = 7.6 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.2 Hz, 2H, –CH2CH2Rf),
4.46 (t, J = 6.6 Hz, 2H, –OCH2), 4.76 (q, J = 6.6 Hz, 1H, –CHCH3), 6.90 (d, J = 8.0 Hz,
2H, ArH), 6.97 (d, J = 8.4 Hz, 2H, ArH), 7.11 (d, J = 8.4 Hz, 2H, ArH), 7.34 (d, J =
8.0 Hz, 2H, ArH), 8.13 (d, J = 8.4 Hz, 2H, ArH), 8.23 (d, J = 8.4 Hz, 2H, ArH). 19F NMR
(400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s, 2F),
(−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.
int.): 966 (M++1),339 (C7H15O–C6H4–COO–C6H4–CO+, 40), 219 (C7H15O–C6H4–CO+,
100), 121 (HO–C6H4–CO+, 64). Elemental analysis: calculated for C40H35O8F17, C 49.70,
H 3.65%; found, C 49.60, H 3.58%.
Synthesis of Compound B8. M.p. 120.0◦C. IR (KBr, cm−1), 2924, 2854, 1753, 1736, 1606,
1511, 1415, and 1199. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.87 (t, J = 5.8 Hz, 3H,
–CH2CH3), 1.15–1.86 (m, 12H, aliphatic hydrogens). 1.62 (d, J = 6.4 Hz, 3H, –CHCH3),
2.48 (tt, J1 = 18 Hz, J2 = 7.8 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.8 Hz, 2H, –CH2CH2Rf),
4.46 (t, J = 4.4 Hz, 2H,–OCH2), 4.76 (q, J = 6.4 Hz, 1H, –CHCH3), 6.90 (d, J = 8.8 Hz,
2H, ArH), 6.96 (d, J = 8.8 Hz, 2H, ArH), 7.10 (d, J = 8.8 Hz, 2H, ArH), 7.33 (d, J =
8.8 Hz, 2H, ArH), 8.13 (d, J = 8.8 Hz, 2H, ArH), 8.23 (d, J = 8.8 Hz, 2H, ArH). 19F NMR
(400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s, 2F),
(−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.
int.): 980 (M++1),353 (C8H17O–C6H4–COO–C6H4–CO+, 12), 233 (C8H17O–C6H4–CO+,
100), 121 (HO–C6H4–CO+, 18). Elemental analysis: calculated for C41H37O8F17, C 50.21,
H 3.80%; found, C 49.96%H 3.69%.
Synthesis of Compound B9. M.p. 112.1◦C. IR (KBr, cm−1), 2923, 2853, 1753, 1737, 1606,
1511, 1416, and 1198. 1H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.89 (t, J = 6.6 Hz, 3H,
–CH2CH3), 1.20–1.89 (m, 14H, aliphatic hydrogens). 1.64 (d, J = 6.4 Hz, 3H, –CHCH3),
2.49 (tt, J1 = 18.6 Hz, J2 = 6.2 Hz, 2H, –CH2Rf), 4.06 (t, J = 6.6 Hz, 2H, –CH2CH2Rf),
4.49 (t, J = 6.2 Hz, 2H, –OCH2), 4.79 (q, J = 6.6 Hz, 1H, –CHCH3), 6.92 (d, J = 8.8 Hz, 2H,
ArH), 6.99 (d, J = 8.8 Hz, 2H, ArH), 7.13 (d, J = 8.8 Hz, 2H, ArH), 7.31 (d, J = 8.8 Hz, 2H,
ArH), 8.15 (d, J = 8.8 Hz, 2H, ArH), 8.24 (d, J = 8.8 Hz, 2H, ArH). 19F NMR (400 MHz,
CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s, 2F), −44.83 (s, 2F), (−43.81
to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz, 3F). MS m/z (rel.int.): 994
(M++1), 367 (C9H19O–C6H4–COO–C6H4–CO+, 13), 247 (C9H19O–C6H4–CO+, 100),
121 (HO–C6H4–CO+, 20). Elemental analysis: calculated for C42H39O8F17, C 50.71, H
3.95%; found, C 50.49, H 3.87%.
Synthesis of Compound B10. M.p. 115.6◦C. IR (KBr, cm−1), 2922, 2852, 1753, 1738,
1
1605, 1510, 1415, and 1198. H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.87 (t, J =
6.4 Hz, 3H, –CH2CH3), 1.20–1.85 (m, 16H, aliphatic hydrogens). 1.62 (d, J = 5.4 Hz,
3H, –CHCH3), 2.47 (tt, J1 = 19.6 Hz, J2 = 6.4 Hz, 2H, –CH2Rf), 4.04 (t, J = 6.4 Hz,
2H, –CH2CH2Rf), 4.47 (t, J = 6.4 Hz, 2H, –OCH2), 4.76 (q, J = 6.9 Hz, 1H, –CHCH3),

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6.90 (d, J = 8.4 Hz, 2H, ArH), 6.97 (d, J = 8.0 Hz, 2H, ArH), 7.11 (d, J = 8.0 Hz, 2H,
ArH), 7.33 (d, J = 8.4 Hz, 2H, ArH), 8.13 (d, J = 8.0 Hz, 2H, ArH), 8.24 (d, J = 8.84 Hz,
2H, ArH). 19F NMR (400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s,
2F), −44.83 (s, 2F), (−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 1008 (M++1), 381 (C10H21O–C6H4–COO–C6H4–CO+, 14), 261
(C10H21O–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 30). Elemental analysis: calculated for
C43H41O8F17, C 51.20, H 4.10%; found, C 50.25, H 4.36%.
Synthesis of Compound B11. M.p. 113.6◦C. IR (KBr, cm−1), 2922, 2852, 1753, 1738,
1
1605, 1510, 1415, and 1198. H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.87 (t, J =
6.8 Hz, 3H, –CH2CH3), 1.20–1.86 (m, 18H, aliphatic hydrogens). 1.62 (d, J = 6.8 Hz,
3H, –CHCH3), 2.47 (tt, J1 = 18.6 Hz, J2 = 6.6 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.6 Hz,
2H, –CH2CH2Rf), 4.47 (t, J = 6.4 Hz, 2H, –OCH2), 4.76 (q, J = 6.8 Hz, 1H, –CHCH3),
6.90 (d, J = 8.8 Hz, 2H, ArH), 6.97 (d, J = 8.8 Hz, 2H, ArH), 7.11 (d, J = 9.2 Hz, 2H,
ArH), 7.34 (d, J = 8.8 Hz, 2H, ArH), 8.13 (d, J = 8.8 Hz, 2H, ArH), 8.24 (d, J = 8.8 Hz,
2H, ArH). 19F NMR (400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s,
2F), −44.83 (s, 2F), (−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 1022 (M++1), 395 (C11H23O–C6H4–COO–C6H4–CO+, 10), 275
(C11H23O–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 18). Elemental analysis: calculated for
C44H43O8F17, C 51.67, H 4.24%; found, C 50.99, H 4.57%.
Synthesis of Compound B12. M.p. 117.8◦C. IR (KBr, cm−1), 2921, 2851, 1755, 1738,
1
1605, 1510, 1415, and 1199. H NMR (400 MHz, CDCl3, TMS): δ (ppm) 0.86 (t, J =
6.6 Hz, 3H, –CH2CH3), 1.20–1.86 (m, 20H, aliphatic hydrogens). 1.62 (d, J = 6.8 Hz,
3H, –CHCH3), 2.47 (tt, J1 = 18.2 Hz, J2 = 6.0 Hz, 2H, –CH2Rf), 4.03 (t, J = 6.6 Hz,
2H, –CH2CH2Rf), 4.47 (t, J = 6.2 Hz, 2H, –OCH2), 4.76 (q, J = 6.8 Hz, 1H, –CHCH3),
6.90 (d, J = 8.8 Hz, 2H, ArH), 6.97 (d, J = 8.8 Hz, 2H, ArH), 7.11 (d, J = 9.2 Hz, 2H,
ArH), 7.33 (d, J = 8.8 Hz, 2H, ArH), 8.13 (d, J = 8.4 Hz, 2H, ArH), 8.24 (d, J = 8.8 Hz,
2H, ArH). 19F NMR (400 MHz, CDCl3): δ (ppm) −48.28 (t, J = 17.6 Hz, 2F), −45.70 (s,
2F), −44.83 (s, 2F), (−43.81 to −44.12) (m, 6F), −35.71 (m, 2F), −2.91 (t, J = 9.87 Hz,
3F). MS m/z (rel. int.): 1036 (M++1), 409 (C12H25O–C6H4–COO–C6H4–CO+, 12), 289
(C12H25O–C6H4–CO+, 100), 121 (HO–C6H4–CO+, 30). Elemental analysis: calculated for
C45H45O8F17, C 52.13, H 4.37%; found, C 51.17, H 4.35%.
Acknowledgments
This work was supported by the Program of Innovative Research Team of Soochow Uni-
versity.
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