Synthesis and mesomorphic properties of some fluorinated benzoate liquid crystals

Article abstract of DOI:10.1080/10587250210534

Three series of [4-(4′-n-alkyloxyphenyl)acetylenyl]-2,6- difluorophenyl fluorinated benezoates and one series of fluorinated benzoates with 2,3,5,6-tetrafluorophenylene group and semi-perfluorocarbon chain have been synthesized. Their phase transition temperatures have been measured by texture observation in a polarizing microscope and confirmed by DSC. For the series without fluorocarbon chains, increasing the quantity of fluorosubstituents on the terminal phenyl groups decreased nematic stability (T_N-I), but the breadth of the SmA phase range was increased. Lateral fluorosubstitution in the central group lowered the nematic stability (T_N-I) and decreased the breadth of the SmA phase range. The series with semiperfluorocarbon chains were more likely to form SmA phases than the series with hydrogencarbon chains, and with the increasing of fluorosubstituents quantity on the terminal phenyl groups nematic and SmA stability (T_N-I and T_smA-N) were both decreased.

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Synthesis and Mesomorphic
Properties of Some Fluorinated
Benzoate Liquid Crystals
Y. G. Yang a , H. Chen a , G. Tang a & J. X. Wen a
a Shanghai Institute of Organic Chemistry, Chinese
Academy of Sciences, Shanghai, China
Published online: 18 Oct 2010.
To cite this article: Y. G. Yang , H. Chen , G. Tang & J. X. Wen (2002) Synthesis and
Mesomorphic Properties of Some Fluorinated Benzoate Liquid Crystals, Molecular
Crystals and Liquid Crystals, 373:1, 1-15, DOI: 10.1080/10587250210534
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Mol. Cryst. and Liq. Cryst., 2002, Vol. 373, pp. 1-15
# 2002 Taylor and Francis, Inc.
Synthesis and Mesomorphic
Properties of Some Fluorinated
Benzoate Liquid Crystals
Y. G. YANG, H. CHEN, G. TANG and J. X. WEN
Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences,
Shanghai, China
Three series of [4-(40-n-alkyloxyphenyl)acetylenyl]-2,6-difluorophenyl fluorinated benezoates
and one series of fluorinated benzoates with 2,3,5,6-tetrafluorophenylene group and semi-per-
fluorocarbon chain have been synthesized. Their phase transition temperatures have been
measured by texture observation in a polarizing microscope and confirmed by DSC. For the
series without fluorocarbon chains, increasing the quantity of fluorosubstituents on the terminal
phenyl groups decreased nematic stability (TN-I), but the breadth of the SmA phase range was
increased. Lateral fluorosubstitution in the central group lowered the nematic stability (TN-I
)
and decreased the breadth of the SmA phase range. The series with semiperfluorocarbon chains
were more likely to form SmA phases than the series with hydrogencarbon chains, and with the
increasing of fluorosubstituents quantity on the terminal phenyl groups nematic and SmA
stability (TN-I and TSmA-N) were both decreased.
Keywords: Fluorinated, liquid crystal, mesomorphic
INTRODUCTION
Fluorinated liquid crystals have been the focus of research in the liquid
crystal field. The introduction of a fluorine atom generally leads to a subtle
modification of properties and imparts many advantageous properties be-
cause it is the smallest substituent and has the highest electronegativity [1–7].
Up to now, thousands of liquid-crystalline molecules with monofluoro-, di-
fluoro-, or trifluorosubstituted phenyls have been prepared [8]. However, on
one hand the fluorosubstituted benzoate liquid crystals have not been carried
Received 28 February 2001; accepted 22 May 2001.
The authors gratefully acknowledge the National Natural Science Foundation of China for
partial financial support.
Address correspondence to Dr. Yong Gang Yang, Shanghai Institute of Organic Chemistry,
Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032 China. E-mail: ygyang@
pub.sioc.ac.ch
1

2
Y.G. YANG et al.
very well [9], especially the benzoates with the 2,6-difluorophenylene group.
On the other hand, it was found that not only para-fluorosubstitution but
also meta-fluorosubstitution of the terminal phenyl group enhances the
formation of SmA phase in the series shown below [10–12]. This
phenomenon may be due to the existence of microphase separation, which
occurs when the number of the fluorine atoms increased beyond a certain
level in the terminal aromatic ring.
To further study this phenomenon, three series of o-, m-, p-fluoro-
substituted benzoates with fluorosubstituents on the central phenylene
groups (not on the terminal group as above) have been synthesized, the
formula of which were shown in Scheme 1.
At the same time, the benzoates with highly fluorinated tails were also
studied (see series A in Scheme 2). It is well-known that increasing the
amount of fluorination, particularly in the terminal chains, favors the
SCHEME 1 The molecular structure of 4Fn0, 34Fn0 and 345Fn0.

MESOMORPHIC PROPERTIES OF SOME BENZOATE COMPOUNDS
3
SCHEME 2
formation of the SmA phase [10]. This is because there is a tendency to
microphase separate—at least that is generally what the picture shows from
X-ray diffraction studies [11–12]. In series A, the increase in fluoro-sub-
stituents in the terminal aromatic ring must affect the microphase separation
generated by the fluorocarbon chain, and thus affect the breadth and thermal
stability (TSmA-N) of the smectic A phase. To evaluate the effect of fluor-
ocarbon chains, we have designated the series A and B for comparison.
RESULTS AND DISCUSSION
The transition temperatures of compounds, 4Fn0[4-(40-n-alkyloxyphenyl)-
acetylenyl]-2,6-difluorophenyl-40-fluorobenzoate, 34Fn0 [4-(40-n-alkylox-
yphenyl)acetylenyl]-2,6-difluorophenyl
3,4-difluorobenzoate,
345Fn0

4
Y.G. YANG et al.
[4-(40-n-alkyloxyphenyl)acetylenyl]-2,6-difluorophenyl 3,4,5-trifluorobenzo-
ate are presented in Table 1. The transition temperatures are plotted against
the number of carbon atoms in the alkoxy chain, n, in Figures 1, 2, and 3.
The phase transition temperatures of compounds in series A and B are listed
in Table 2, and shown as a bar graph in Figure 4.
The compounds of series 4Fn0, 34Fn0, and 345Fn0 showenantiotropic N
phases except for 345F40. With the increase in alkoxy chain length, the
clearing point reduces and the width of the range of the nematic phase
exhibits a maximum. Compounds 4Fn0 exhibit enantiotropic nematic pha-
ses, and monotropic SmA phases are found when the carbon number of the
alkoxy chain n > 10. Similar to series 4Fn0, compounds 34Fn0 exhibit
monotropic SmA phases when n > 7 and enantiotropic SmA phases when
n > 10. The clearing point decreases gradually with the increase in the
terminal chain length. Compared with compounds 34Fn0, compounds
345Fn0 exhibit monotropic SmA phases when n > 7. This may due to the
fact that two meta-fluorosubstituents broaden the molecule much more than
TABLE 1 Transition temperatures of compounds 4Fn0, 34Fn0, and 345Fn0
Compounds
Name
n
Transition temperatures (ꢀC)
4Fn0
4F50
4F60
4F70
4F80
4F90
4F100
4F120
4F160
5
6
7
8
9
10
12
16
Cr 89.9 N 150.1 I 149.6 N 97.1 Recr
Cr 95.3 N 145.6 I 144.1 N 46.8 Recr
Cr 79.3 N 136.3 I 135.3 N 35.7 Recr
Cr 87.6 N 133.4 I 132.3 N 35.9 Recr
Cr 88.9 N 126.4 I 125.1 N 58.5 Recr
Cr 79.8 N 124.1 I 123.2 N 37.8 Recr
Cr 72.9 N 119.5 I 117.1 N 55.3 SmA 27.2 Recr
Cr 85.0 N 109.7 I 108.2 N 76.2 SmA 47.8 Recr
34Fn0
34F40
34F50
34F60
34F70
34F80
34F90
34F100
34F120
34F160
4
5
6
7
8
Cr 85.0 N 122.1 I 119.6 N 47.1 Recr
Cr 71.1 N 122.6 I 121.3 N 29.6 Recr
Cr 68.6 N 122.0 I 120.6 N 24.7 Recr
Cr 67.3 N 113.4 I 112.6 N 27.0 Recr
Cr 73.2 N 112.0 I 110.7 N 34.9 SmA 29.6 Recr
Cr 69.6 N 106.8 I 106.0 N 50.1 SmA 34.2 Recr
Cr 60.5 N 105.5 1104.4 N 60.4 SmA 28.2 Recr
Cr 50.5 SmA 75.0 N 101.0 I 99.3 N 73.4 SmA 24.5 Recr
Cr 64.7 SmA 83.3 N 95.2 I 93.8 N 82.7 SmA 49.1 Recr
9
10
12
16
345Fn0
345F40
345F50
345F60
345F70
345F80
345F90
345F100
345F120
345F160
4
5
6
7
8
Cr 120.0 I 103.8 N 56.1 Recr
Cr 95.8 N 97.3 I 96.7 N 56.4 Recr
Cr 86.1 N 98.1 I 97.3 N 60.8 Recr
Cr 76.1 N 91.2 I 90.5 N 52.8 Recr
Cr 76.1 N 89.9 I 89.0 N 61.1 SmA 46.3 Recr
Cr 80.1 N 87.2 I 86.1 N 61.9 SmA 42.3 Recr
Cr 80.1 N 89.9 I 88.8 N 74.4 SmA 54.5 Recr
Cr 80.2 N 87.5 I 86.5 N 78.8 SmA 44.7 Recr
Cr 81.4 N 82.8 I 81.4 N 79.6 SmA 61.9 Recr
9
10
12
16
Cr, Crystal; SmA, Smectie A phase; N, Nematic phase; I, Isotropic phase; Recr, Recrystal.

MESOMORPHIC PROPERTIES OF SOME BENZOATE COMPOUNDS
5
FIGURE 1 The transition behavior of series HFn0: dependence of transition temperatures on
the number (n) of the aloxy chain.
one meta-fluorosubstituent does. From all these data listed in Table 1 the
same result is obtained, namely that to increase the number of fluorosub-
stituents on the terminal phenyl group promotes the formation of the SmA
phase. This means that with increasing fluorosubstitution in the terminal
phenyl group, the terminal-terminal attractions are disrupted step by step.
That the melting point of compounds 4Fn0 or 345Fn0 are higher than that of
the corresponding compound 34Fn0 may be due to molecular symmetry.
Comparing compounds 4F80, 34F80, and 345F80 with the three com-
pounds 4F8, 34F8, and 345F8 without lateral fluorosubstituents in the
central phenylene group [10], respectively (see Figure 5), the lateral fluor-
osubstitution on the central phenylene group lowers the clearing point and
narrows the breadth of the smectic phase range. This is because the lateral
fluorosubstitution increases the breadth of molecules and reduces the
lateral-lateral interaction. It is also because of this that the crystalline

6
Y.G. YANG et al.
FIGURE 2 The transition behavior of series 34Fn0: dependence of transition temperatures on
the number (n) of the alkoxy chain.
temperatures of compounds series 4Fn0, 34Fn0, and 345Fn0 are lower than
those of compounds 4Fn, 34Fn, and 345Fn respectively.
In a word, the lateral fluorosubstituents on the central group of series
4Fn0, 34Fn0, and 345Fn0 reduce the nematic stability and the melting point.
Similar to other series with fluorosubstituents on the terminal phenylene
group [10–12], increasing the number of fluorosubstituents on the terminal
group will promote the formation of smectic phases.
In series A, the system with a fluorinated tail, it is found that the clearing
point of A4 is the highest, 156.9ꢀC. Meanwhile, the clearing point of A35 is
the lowest, 98.2ꢀC. This is related to the steric and electronic effects of fluorine
atoms. Considering the steric effect, the protrusion of the meta-fluorosub-
stituent in A35 will tend to disrupt the side-to-side intermolecular forces of
attraction which reduce the clearing point. As to compounds A35 and A345, it
is found that the para-fluorosubstitution increases the clearing point and

MESOMORPHIC PROPERTIES OF SOME BENZOATE COMPOUNDS
7
FIGURE 3 The transition behavior of series 345Fn0: dependence of transition temperatures
on the number (n) of the alkoxy chain.
enhances the formation of the nematic phase. This may be due to the elec-
tronic effect of the fluorosubstitution, which might enhance the formation of
pairwise associations [13, 14]. As for compounds A4, A34, and A345, it is
found that the meta-fluorosubstitution affects the tendency to form the SmA
TABLE 2 The transition temperatures of compounds in series A and B
Compounds
Transition temperatures=ꢀC
A345
B345
A35
B35
A34
B34
A4
Cr 103.3 N 103.7 I 101.6 N 62.1 Recr
Cr 93.0 SmA 109.0 N 132.6 I 131.1 N 107.4 SmA 57.8 Recr
Cr 97.6 SmA 98.2 I 97.6 SmA 64.6 Recr
Cr 65.3 N 68.8 I 66.6 N 55.0 Recr
Cr 94.4 SmA 106.6 N 129.4 I 126.9 N 103.0 SmA 51.1 Recr
Cr 58.0 SmA 75.4 N 152.0 I 149.6 N 72.5 SmA 47.7 Recr
Cr 102.0 SmA 140.2 N 156.9 I 155.4 N 138.4 SmA 72.1 Recr
Cr 91.9 N 170.1 I 168.6 N 63.7 Recr
B4
Cr, Crystal; SmA, Smectic A phase; N, Nematic phase; I, Isotropic phase;
Recr, Recrystallization.

8
Y.G. YANG et al.
FIGURE 4 The mesomorphic properties of compounds in series A and B. Cr ¼ Crystal;
SmA ¼ Smectic A phase; N ¼ Nematic phase.
phase. This is different from the phenomenon in series B in which the meta-
fluorosubstituent enhances the tendency to form the SmA phase [11].
In series A, both the fluorocarbon chain and the fluorosubstituted terminal
aromatic ring showlowcohesive energy density, which is the main reason for
microphase separation in fluorinated compounds. Thus, similar to fluor-
ocarbon chains, the fluorosubstituent in the terminal aromatic rings may also
change the polyphilic property of the whole molecule. In series A, tw o
terminals were both fluorinated, and the whole molecule may lose the
polyphilic property. Therefore, with the increase in meta-fluorosubstituents
in the terminal phenyl group, the thermal stability of the smectic A phase,
which is stabled by the polyphilic property of fluorocarbon chains, is de-
creased. But due to the strong microphase separation of series A, compound
of series A is more favorable to form smectic A phase than that in the series B.
Comparing the two series, series A with the fluorinated tail generally
decreases the clearing point and increases the melting point. The increasing
of melting points of the compounds in series A is probably due to the
rigidity of the fluorocarbon chain.

MESOMORPHIC PROPERTIES OF SOME BENZOATE COMPOUNDS
9
FIGURE 5 Comparison of mesomorphic properties of selected compounds. Cr ¼ Crystal;
SmA ¼ Smectic A phase; N ¼ Nematic phase.
Considering the compounds studied above, we know that the para-
fluorosubstitution meta-fluorosubstitution in the terminal phenyl group
in combination with the fluorosubstitution in the tail tend to form the
SmA phase. However, they might disturb each other during the for-
mation of microphase separation due to the same lowcohesive energy
density.
EXPERIMENTAL
Compound 3 can be easily obtained according to the published procedure
[15]. Compound 4 was prepared from compound 3 directly through a bro-
mosubstitution step. Then compound 6 was synthesized via a mild one-pot
esterification procedure, between 4 and 5 in the presence of both dicyclo-
hexylcarbodiimide (DCC) and DMAP catalyst in dried THF. Compound 10
can be obtained according to our published procedure [16]. Finally, the
coupling reaction between compounds 6 and 10 under the catalysis of

10
Y.G. YANG et al.
bis(triphenylphosphine) palladium dichloride, triphenylphosphine and
copper(I) iodide in dried triethylamine and THF gave the compounds 4Fn0,
34Fn0, and 345Fn0.
Infrared spectra were scanned on a PE-983G spectrophotometer. 1H
NMR spectra were recorded on a FX-90Q (90 MHz), a Varian 360L
(60 MHz) or a Brucker 300 NMR (300 MHz) spectrometer with TMS as the
internal standard. 19F NMR spectra, with trifluoroacetic acid (TFA) as
external standard and CDCl3 as the solvent, were recorded on a Varian EM
360L (56.4 MHz) spectrometer (high field positive). Mass spectra were
measured with a Finnigan 4021 spectrometer. Elemental analyses were
performed on a Heraeus Rapid CHN-O (Germany) instrument. The me-
sophase textures were observed on the Olympus BH2 polarized microscope
in conjunction with a Mettler FP-52 heat-stage, equipped with a FP-5
control calorimetry at the heating rate of 5ꢀC=min and cooling down
naturally under a nitrogen atmosphere on a Shimadzu DSC-50 system and
data station. The transition peaks were used as the transition temperatures.
The liquid crystal molecules studied were synthesized following the route
as shown in Scheme 3 [17].
2,6-Difluorophenol (3) [15]
Butyl-lithium (1.6 mol=L in hexane, 33 mL, 52.8 mmol) was added drop-
wise to a stirred, cooled (À78ꢀC) solution of compound (1) (5.8 g,
46.3 mmol) in dry THF (65 mL) under dry nitrogen. The reaction mixture
was maintained under these conditions for 2.5 h, and then a previously
cooled solution of trimethyl borate (10.4 g, 100.0 mmol) in dry THF
(25 mL) was added dropwise at À78ꢀC. The reaction mixture was allowed
to warm to r.t. overnight and was then stirred for 1 h with 10% hydro-
chloric acid (30 mL). The product was extracted into ether (twice), then
the combined ethereal extracts were washed with water and dried
(MgSO4). The solvent was removed in vacuo to yield colorless crystals
(8.0 g). 10% Hydrogen peroxide (50 mL, 146.7 mmol) was added dropwise
to a stirred solution of these colorless crystals in ether (50 mL) heated
under reflux. The stirred mixture was heated under reflux for 2.5 h and
then cooled. The ether layer was separated and the aqueous layer was
washed with ether. The combined ethereal layers were washed with water
and dried (MgSO4). The solvent was removed in vacuo and the residue was
purified by flash chromatography to give an off-white solid (5.59 g). Yield:
85.3%. dF (CDCl3): 59.1(s, 2F) ppm. m=z(%): 130(100.00), 82(55.78),
110(23.32).

MESOMORPHIC PROPERTIES OF SOME BENZOATE COMPOUNDS
11
SCHEME 3 The synthesis route of series 4Fn0, 34Fn0 and 345Fn0. Reagents and condition: (1)
a) n-C4H9Li=THF; B(OMe3)=THF, À78ꢀC to r.t.; b) H3 þ O, r.t.; (2) H2O2, Et2O, r.t.; (3) Br2,
CH3COOH, 0ꢀC; (4) DCC, DMAP, r.t. THF; (5) n-H(CH2)nBr, CH3COCH3, K2CO3, reflux;
(6) Pd(PPh3)2Cl2, HCꢁCC(CH3)2OH, CuI, Et3N, 70ꢀC; (7) KOH, C6H5CH3, reflux;
(8) Pd(PPh3)2Cl2, CuI, Et3N, THF, reflux.
2,6-Difluoro-4-bromophenol (4)
A solution of bromine (15.0 g, 92.6 mmol) in glacial acetic acid (6 mL) was
added slowly, dropwise to a stirred solution of 2, 6-difluorophenol (3)
(10.0 g, 76.9 mmol) in glacial acetic acid (20 mL), keeping the temperature

12
Y.G. YANG et al.
ꢀ
below0 C. The mixture was stirred at r.t. for 4 h, and then sodium thio-
sulphate (5 g), sodium acetate (12.5 g) and water (50 mL) were added and
the mixture was cooled in a refrigerator overnight. The product was ex-
tracted into ether (twice), then the combined ethereal extracts were washed
with 10% sodium hydroxide water and dried (MgSO4). The solvent was
removed in vacuo and the residue was purified by flash chromatography to
give a yellowsolid (11.5 g). Yield: 71.7%. dF (CDCl3): 54.8(s, 2F) ppm.
m=z(%): 210(100.00), 208(99.69), 162(24.92), 160(25.76), 81(52.05).
(2,6-Difluoro-4-bromophenol) 4-fluorobenzoate (6a)
2,6-Difluoro-4-bromophenol (3.9 g, 18.6 mmol), 4-fluorobenzoic acid
(2.8 g, 20 mmol), N,N0-dicyclohexylcarbodiimide (4.0 g, 19.2 mmol), cata-
lytic DMAP and dry THF (40 mL) were stirred under dry nitrogen at room
temperature for 24 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 to give a white solid
(3.3 g). Yield: 53.2%. dF (CDCl3): 46.5(s, 2F), 25.5(s, 1F) ppm. m=z(%):
330(1.41), 123(71.13), 95(100.00).
(2,6-Difluoro-4-bromophenol) 3,4-difluorobenzoate (6b)
The experiment procedure was as described for the preparation of com-
pound (6a). dF (CDCl3): 57.9(m, 1F), 49.9(m, 1F), 46.1(s, 2F) ppm. m=z(%):
348(0.42), 141(100.00).
(2,6-Difluoro-4-bromophenol) 3,4,5-trifluorobenzoate (6c)
The experiment procedure was as described for the preparation of com-
pound (6a). dF (CDCl3): 72.6(m, 1F), 54.5(m, 2F), 46.5(s, 2F) ppm. m=z(%):
367(1.05, M þ 1), 365(1.07), 159(100.00).
[4-(40-n-Pentoxyphenyl)acetylenyl]-2,6-difluorophenyl
4-fluorobenzoate (4F50)
A typical procedure: Under dry nitrogen, into a mixture of compound 4-n-
pentoxyphenylacetylene (10) (190 mg, 1.02 mmol), compound 6a (300 mg,
0.909 mmol), bis(triphenylphosphine)palladium dichloride (30 mg) and
copper (I) iodide (50 mg) were added 15 mL of anhydrous triethylamine.
The resulting mixture was refluxed while it was stirred. Analysis by TLC
revealed completion of the reaction within 8 h. Then the formed precipitate
was filtered and the solvent was removed in vacuo. The residue was purified

13

14
Y.G. YANG et al.
by flash chromatography and recrystallized from acetone-methanol to give a
white solid (210 mg). Yield: 50.4%. Mp 150.1ꢀC. nmax (KBr): 2940, 2200,
1750, 1610, 1520, 1380, 1300, 1280, 1170, 1050, 840, 760 cmÀ1. dH(CDCl3):
0.90–1.30(m, 3H), 1.30–2.23(m, 6H), 4.10(t, 2H, J ¼ 6.8 Hz), 6.83–8.60(m,
10H) ppm. dF (CDCl3): 48.1(d, 2F, J ¼ 7.8 Hz), 25.0(s, 1F) ppm. m=z(%):
438(13.91), 373(41.44), 234(64.27), 123(100.00). HRMS: C26H21O3F3.
Calcd: 438.1443. Found: 438.1448.
[4-(40-n-Butoxyphenyl)acetylenyl]-2,6-difluorophenyl
3,4-difluorobenzoate (34F40)
Mp 122.1ꢀC. nmax (KBr): 2963, 2210, 1753, 1603, 1520, 1375, 1298, 1248,
1184,1050, 926, 751, 570 cmÀ1. dH (CDCl3): 0.90–1.28(m, 3H), 1.26–2.13(m,
4H), 4.20(t, 2H, J ¼ 6.0 Hz), 6.97–8.40(m, 9H) ppm. dF (CDCl3): 57.61–
57.75(m, 1F), 49.76–49.91(m, 1F),48.14(d, 2F, J ¼ 6.8 Hz) ppm. m=z(%):
442(33.29), 141(100.00). Anal. C25H18F4O3. Calcd: H, 4.10; C, 67.87; F,
17.18. Found: H, 4.40; C, 68.09; F, 16.64.
[4-(40-n-Butoxyphenyl)acetylenyl]-2,6-difluorophenyl
3,4,5-trifluorobenzoate (345F40)
Mp 120.0ꢀC. nmax (KBr): 2950, 2200, 1760, 1610, 1520, 1440, 1360, 1250,
1190, 1040, 940, 830, 760 cmÀ1. dH(CDCl3): 0.90–1.25(m, 3H), 1.25–2.10(m,
4H), 4.18(t, 2H, J ¼ 6.0 Hz), 6.90–8.20(m, 8H) ppm. dF (CDCl3): 72.0–
73.3(m, 1F), 53.3–54.7(m, 2F), 48.5(d, 2F, J ¼ 7.8 Hz) ppm. m=z(%):
460(37.30), 159(100.00). HRMS: C25H18F4O3. Calcd: 460.1098. Found:
460.1113.
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