Synthesis and mesomorphic properties of a new series of triazole bent-core liquid crystalline molecules by "click" reaction

Article abstract of DOI:10.1080/15421406.2015.1044713

The synthesis and mesomorphic properties of new triazole liquid-crystalline are presented and discussed. These triazole derivatives have been synthesized by reacting 4-hydrazoic iodobenzene with the 4-alkyl phenyl acetylene in dimethyl formamide (DMF). Th

Full text of DOI:10.1080/15421406.2015.1044713

Molecular Crystals and Liquid Crystals
ISSN: 1542-1406 (Print) 1563-5287 (Online) Journal homepage: http://www.tandfonline.com/loi/gmcl20
Synthesis and mesomorphic properties of a new
series of triazole bent-core liquid crystalline
molecules by “click” reaction
Yu-Zhen Zhao, Ze-Min He, Gang Chen, Zong-Cheng Miao, Dong Wang & Hai-
Quan Zhang
To cite this article: Yu-Zhen Zhao, Ze-Min He, Gang Chen, Zong-Cheng Miao, Dong Wang & Hai-
Quan Zhang (2016) Synthesis and mesomorphic properties of a new series of triazole bent-
core liquid crystalline molecules by “click” reaction, Molecular Crystals and Liquid Crystals,
624:1, 171-179, DOI: 10.1080/15421406.2015.1044713
To link to this article: http://dx.doi.org/10.1080/15421406.2015.1044713
Published online: 11 Feb 2016.
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Date: 03 March 2016, At: 23:17

MOL. CRYST. LIQ. CRYST.
, VOL. , NO. , –
http://dx.doi.org/./..
Synthesis and mesomorphic properties of a new series of
triazole bent-core liquid crystalline molecules by “click”reaction
Yu-Zhen Zhaoa, Ze-Min Hea, Gang Chenb, Zong-Cheng Miaoc, Dong Wangc, and
Hai-Quan Zhanga
aState Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, China;
bDepartment of Materials Science and Engineering, College of Engineering, Peking University, Beijing, China;
cDepartment of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing, China
ABSTRACT
KEYWORDS
Bent-core; click reaction;
mesomorphic behavior;
Sonogashira coupling;
triazole liquid-crystalline
The synthesis and mesomorphic properties of new triazole liquid-
crystalline are presented and discussed. These triazole derivatives have
been synthesized by reacting 4-hydrazoic iodobenzene with the 4-alkyl
phenyl acetylene in dimethyl formamide (DMF). The molecular structure
is characterized by 1H NMR, Fouriertransforminfraredspectroscopy (FTIR),
time-of-flightmassspectrometry(TOF-MS)andthemesomorphicproper-
ties are characterized by polarizing optical microscope (POM) and (DSC).
These new triazole liquid-crystallines have higher melting point and
clearing point and the final compounds display both nematic and smec-
tic liquid-crystalline phases.
1. Introduction
As is known to all, chemical structure has a most significant effect on the mesophases formed
by a liquid crystal material, therefore, it has become clear that what type of molecules should
be able to form a mesophase. Obviously, rod-like molecules or disk-shaped can exhibit
nematic phases. In addition, calamitic mesogens form lamellar phases while discotic meso-
gens form columnar phases. Different ways of these basic molecular structures giving rise to
structural features of the mesophases can be modified. Since Niori et al. have first reported the
synthesis of bent-core liquid crystals and found their special property, it seems that the bent or
banana-shaped liquid crystals represent a new subfield of liquid crystals. Banana mesophases
formed by bent core mesogens have become targets of great interest in academic research and
their potential applications [1–7]. Due to their characteristic structure–property relationships,
these have played an important role in displaying novel mesophases exhibiting polar and chi-
ral properties.
At an early stage of the discovery of the bent-core liquid crystals, seven mesogenic phases
were identified and simply designated as B1–B7, as specific phases different from conven-
tional phases found in calamitic mesogens [8]. Sharpless and coworkers introduced “click”
chemistry, a novel approach in organic synthesis that involves a handful of almost perfect
chemical reactions [9].
CONTACT Hai-Quan Zhang
hqzhang@ysu.edu.cn
ogy, Yanshan University, Qinhuangdao, China.
State Key Laboratory of Metastable Materials Science and Technol-
Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/gmcl.
©  Taylor & Francis Group, LLC

172
Y.-Z. ZHAO ET AL.
Figure . Schematic representation of a CuAAC reaction.
The CuI catalyzed azide–alkyne cycloaddition (CuAA C) can be considered as a typical
“click” reaction [10] (Fig. 1). As part of our continuing interest in the synthesis of new liquid
crystals (LCs), we explored the synthetic potential of triazole in the preparation of new LC
materials.
2. Experimental
Reagents were purchased from commercial sources (Aldrich) and used without further purifi-
cation, apart from triethylamine (TEA) and tetrahydrofuran (THF), which were distilled
under argon before use. Reactions were carried out in an inert atmosphere (dry Ar). The
structures of the various synthetic intermediates and final compounds were characterized
1
by H nuclear magnetic resonance (NMR) spectra of the samples with tetramethylsilane
(TMS) as internal standard, which were recorded on a Bruker DMS (300 MHz) spectrom-
eter instrument. Fourier transform infrared (FTIR) spectra were recorded on a Nicolet-510P
spectrophotometer using a powered sample on a KBr plate. MALDI-TOF mass spectra were
determined on a Shimadzu AXIMA-CFR mass spectrometer.
The optical textures were measured using a polarizing optical microscope (POM, Olympus
BX51) equipped with a hot stage (Linkam LK-600PM) calibrated to an accuracy of 0.1 K,
and the phase transition temperatures and corresponding enthalpy changes of the target com-
pounds were measured by differential scanning calorimetry (DSC, Perkin-Elmer Pyris 6) at
a heating rate of 10.0°C min−1 under a dry nitrogen purge. UV-vis absorption spectra were
recorded on UV-3100 spectrophotometer. Fluorescence spectra were carried out with RF-
5301PC.
3. Results and discussion
The preparative routes and reagents for triazole liquid-crystalline are shown in Scheme 1,
and the detailed synthetic processes are acquired elsewhere in references. In these targeted
compound, the bent core of 1,2,3-triazole was synthesized through a classical reaction of CuI
catalyzed azide–alkyne cycloaddition (CuAAC), which is a typical “click” reaction, and the
Sonogashira coupling reaction with a palladium catalyst plays a key role in the synthesis pro-
cedure. In six compounds we synthesized, 1b was not purified due to its low solubility.
3.1. Phase transitions
DSC was used to determine the phase transition temperatures of the compounds, these are
listed in Table 1. The compounds all exhibited mesophases and with high melting points. In
the DSC analysis of the compounds, only the Cr–N or Cr–Sm transitions were detected while
the absence of N–I or Sm–I transitions suggests a highly disordered fluid mesophase [11]. The
melting point of the compounds decreased with the increase of terminal alkyl chain length.
The long alkyl chain shortened the π-electron conjugation and decreased the molecule rigid-
ity. In contrast to the previously reported [12], the compounds with terminal trifluoromethyl
group have higher melting points than those with terminal cyano group, correspondingly.

MOL. CRYST. LIQ. CRYST.
173
Scheme . Reagents and conditions: (a) HCI, HO, NaNO, NaN, °C,  hr; (b) CuI, DMF, °C; (c) TEA, THF,
CuI, PPh, PdCl(PPh), °C,  hr; (d) MeOH, THF, KCO, room temperature,  hr.
Table . Phase transition temperatures (°C)/ (enthalpy/kJ mol−) of the compounds.
Phase transition temperatures
Compound
(°C)/(enthalpy/kJ mol−
)
1a
Cr(.), N, decomposition, I
C (.), N, decomposition, I
Cr(.), N, decomposition, I
Cr(.), Sm, decomposition, I
Cr(.), Sm, decomposition, I
3a
5a
3b
5b
That is due to the fluorosubstituent decreased molecular packing density. We only report
mesomorphic properties of other compounds.
3.2. Optical textures
The optical textures of these compounds were observed with hot-stage POM (see Fig. 2). For
3a and 5a with terminal cyano group, the typical schlieren texture was observed, seeFig. 2(3a).
However, the typical fingerprint texture was found, see Fig. 2(5a). Possibly, this is due to that
the molecules of 5a are of asymmetric order with spontaneity [13]. The optical textures of
compounds 3b and 5b are similar in each case, manifesting a fan-like texture together [14]
with large areas of oblique arrangement texture (see Fig. 2(3b) and (5b)).

174
Y.-Z. ZHAO ET AL.
Figure . Microphotographs of the liquid crystalline phases of compounds 3a, 5a, 3b and 5b cooling rate:
°C min−.
3.3. Optical properties
The photophysical properties of compounds 3a and 3b were examined by UV-vis spec-
troscopy and fluorescence spectroscopy in dilute CH2Cl2 solution at room temperature as
shown in Fig. 3. All the data were summarized in Table 2 including absorption maxima (λabs),
PL emission maxima (λem), and the Stokes shifts. The UV-vis absorption spectra were shown
in Fig. 3(a). For 3a and 3b, both exhibit well-resolved absorption peaks because of π-π∗
conjugation absorption [15]. The bathochromic shift from 3b to 3a was due to their slightly
stronger polarity. For the same reason, the emission characteristics of 3a and 3b in Fig. 3(b)
have been bathochromatically tuned obviously in the visible region. The maximum absorp-
tion edge of the compounds was 362 nm. The use of these materials would be suitable for
optical display applications because such applications do not have an absorption band in the
visible region.
4. Conclusions
By using the CuI catalyzed azide–alkyne cycloaddition (CuAAC) and Hagihara-Sonogashira
cross-coupling reaction, a new series of 1,2,3-triazole derivatives were prepared with polar
groups in excellent yield. All the compounds revealed fully characterized bent-core liquid
crystalline. The compounds have relatively high melting and clearing temperatures that is due
to the strong conjugate structure and the POM texture is very interesting. The results obtained
by inspecting the absorption and emission spectra of these pure compounds indicated that the
1,2,3-triazole derivatives were affected by polarity of terminal group. The present study opens
up a venue for click reaction in the design and synthesis of bent core liquid crystal.
Table . Physical properties of the materials a and b.
Stokes
shift (nm)
Compound
λabs (nm)
λem (nm)
3a
3b







MOL. CRYST. LIQ. CRYST.
175
Figure . (a) The UV-visible spectra of synthesized compounds 3a and 3b. (b) The emission spectra of syn-
thesized compound 3a and 3b.
5. Synthesis
1-Azido-4-iodo-benzene
A solution of 4-iodo-phenylamine (6.3 g, 28.8 mmol) in 20 ml (HCl:H2O; 1:1) was cooled to
0°C in an ice-water bath. A solution of NaNO2 (2.0 g, 28.8 mmol) in 100 ml water was added
dropwise through a syringe to the vigorously stirred solution. After stirred at 0°C, adding a
solution of NaN3 (1.88 g, 28.8 mmol) in 20 ml water by drops into the mixed solution. After
stirred at 0°C for half an hour, after the reaction was done, it was extracted with CH2Cl2 (3 ×
50 ml) and dried over anhydrous MgSO4, filtered, and concentrated. Obtain the target product
as dark brownish solid (6.4 g, 91%).1H NMR (400 MHz, CDCl3): δ = 7.36 (d, J = 8.0 Hz, 2
H), 7.28 (d, J = 8.0 Hz, 2 H) ppm; FTIR (KBr): ν = 2109, 1692, 1604, 1568, 1522, 1483, 1462,
1415, 1402, 1368, 1293, 1207, 1183, 1145, 1060, 816, 721 cm−1. MALDI-TOF-MS (dithranol):
m/z: calcd for C6H4IN3: 244.94 g mol−1, found: 245.03 g mol−1 [MH]+.
1-(4-Iodo-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole (Procedure A)
1-Azido-4-iodo-benzene (2.44 g, 10 mmol) was reacted with 1-ethynyl-4-methylbenzene
(1.16 g, 10 mmol). Then added CuI (95 mg, 0.5 mmol). The reaction mixture was then stirred
at 100°C for 10 hr. After the reaction was done, remove the solvent by vacuum distillation.
The crude product was purified by column chromatography (silica gel, 3:1, hexanes:CH2Cl2)
to give target product (3.25 g, 90%) as a white solid. 1H NMR (400 MHz, CDCl3): δ = 8.21 (s,
1 H), 7.96 (d, J = 8.0 Hz, 2 H), 7.87 (d, J = 8.0 Hz, 2 H), 7.64 (d, J = 8.0 Hz, 2 H), 7.35 (d, J
= 8.0 Hz, 2 H) ppm; FTIR (KBr): ν = 3115, 2925, 2853, 1606, 1584, 1524, 1467, 1404, 1361,
1325, 1273, 1181, 1145, 1062, 956, 816, 722 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd
for C15H12IN3: 361.01 g mol−1, found: 361.18 g mol−1 [MH]+.
1-(4-Iodo-phenyl)-4-(4-propyl-phenyl)-1H-[1,2,3]triazole
The synthesized process of product as described in procedure A in a yield of (92%) as a white
1
solid. H NMR (400 MHz, CDCl3): δ = 8.17 (s, 1 H), 7.88 (d, J = 8.0 Hz, 2 H), 7.81 (d, J
= 8.0 Hz, 2 H), 7.57 (d, J = 8.0 Hz, 2 H), 7.28 (d, J = 8.0 Hz, 2 H) ppm; FTIR (KBr): ν =
3113, 2925, 2851, 1606, 1584, 1524, 1467, 1404, 1362, 1325, 1273, 1182, 1145, 1062, 956, 812,

176
Y.-Z. ZHAO ET AL.
720 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C17H16IN3: 389.04 g mol−1, found:
389.23 g mol−1 [MH]+.
1-(4-Iodo-phenyl)-4-(4-pentyl-phenyl)-1H-[1,2,3]triazole
The synthesized product as described in procedure A in a yield of (93%) as a white solid. 1H
NMR (400 MHz, CDCl3): δ = 8.11 (s, 1 H), 7.85 (d, J = 8.0 Hz, 2 H), 7.78 (d, J = 8.0 Hz, 2 H),
7.54 (d, J = 8.0 Hz, 2 H), 7.25 (d, J = 8.0 Hz, 2 H), 2.62 (t, 2 H), 1.27 (m, 2 H), 1.53 (m, 2 H),
1.62 (m, 2 H), 0.87 (t, 3 H) ppm; FTIR (KBr): ν = 3116, 2923, 2852, 1644, 1605, 1568, 1522,
1483, 1466, 1415, 1402, 1368, 1293, 1203, 1183, 1144, 1060, 816, 721 cm−1. MALDI-TOF-MS
(dithranol): m/z: calcd for C19H20IN3: 417.07 g mol−1, found: 417.26 g mol−1 [MH]+.
1-(4-Trimethylsilanylethynyl-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole
(Procedure B)
1-(4-Iodo-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole (2.89 g, 8 mmol) and Trimethylsi-
lylacetylene (TMSA) (0.87 g, 8.8 mmol) dissolved in 120 ml dry Et3N:THF (1:1) in a 250 ml
round-bottom flask. Add PdCl2(PPh3)2 (0.12 g, 0.16 mmol) and CuI (0.06 g, 0.32 mmol).
The reaction mixture was then stirred at room temperature for 8 hr under an Ar atmosphere.
Upon completion, the solvent was removed in vacuo and the crude material was purified by
chromatography on silica gel (2:1, hexanes:CH2Cl2) to give target compound (2.1 g, 81%) as
a white solid. 1H NMR (400 MHz, CDCl3): δ = 8.14 (s, 1 H), 7.77 (d, J = 8.0 Hz, 2 H), 7.73 (d,
J = 8.0 Hz 2 H), 7.61 (d, J = 8.0 Hz, 2 H), 7.25 (d, J = 8.0 Hz, 2 H), 2.38 (s, 3 H), 0.26 (s, 9 H)
ppm; FTIR (KBr): ν = 3108, 2924, 2852, 2205, 1581, 1522, 1466, 1399, 1349, 1181, 961, 862,
720 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C20H21N3Si: 331.15 g mol−1, found:
331.4 g mol−1 [MH]+.
1-(4-Trimethylsilanylethynyl-phenyl)-4-(4-propyl-phenyl)-1H-[1,2,3]triazole
The synthesized product as described in procedure B in a yield of (82%). 1H NMR (400 MHz,
CDCl3): δ = 8.17 (s, 1 H), 7.81 (d, J = 8.0 Hz, 2 H), 7.76 (d, J = 8.0 Hz, 2 H), 7.65 (d, J =
8.0 Hz, 2 H), 7.28 (d, J = 8.0 Hz, 2 H), 2.65 (t, 2 H), 1.70 (m, 2 H), 0.98 (t, 3 H) ppm; FTIR
(KBr): ν = 3109, 2923, 2852, 2199, 1606, 1584, 1523, 1467, 1404, 1363, 1325, 1273, 1183, 1145,
1062, 957, 814, 720 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C22H25N3Si: 359.18 g
mol−1, found: 359.54 g mol−1 [MH]+.
1-(4-Trimethylsilanylethynyl-phenyl)-4-(4-pentyl-phenyl)-1H-[1,2,3]triazole
The synthesized product as described in procedure B in a yield of (82%). 1H NMR (400 MHz,
CDCl3): δ = 8.14 (s, 1 H), 7.79 (d, J = 8.0 Hz, 2 H), 7.74 (d, J = 8.0 Hz, 2 H), 7.61 (d, J =
8.0 Hz, 2 H), 7.25 (d, J = 8.0 Hz, 2 H), 2.63 (t, 2 H), 1.63 (m, 2 H), 1.60 (m, 2 H), 1.32 (m,
2 H), 0.87 (t, 3 H), 0.25 (s, 9 H) ppm ; FTIR (KBr): ν = 3109, 2924, 2853, 2213, 1604, 1483,
1466, 1345, 1212, 1184, 995, 882, 800, 724 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for
C24H29N3Si: 387.21 g mol−1, found: 387.4 g mol−1 [MH]+.

MOL. CRYST. LIQ. CRYST.
177
1-(4-Ethynyl-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole (Procedure C)
1-(4-Trimethylsilanylethynyl-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole
(1.6
g,
5 mmol) was dissolved in 100 ml of THF: MeOH (7:3) and K2CO3 (1.38 g, 10 mmol)
was added. The reaction mixture was stirred at room temperature for 3 hr. On completion
the mixture was suction filtered. The solvent was removed in vacuo and the crude product
was purified by chromatography on silica gel (CH2Cl2) to give target compound (1.1 g, 90%)
as a white solid.
1H NMR (400 MHz, CDCl3): δ = 8.13 (s, 1 H), 7.78 (d, J = 8.0 Hz, 2 H), 7.76 (d, J =
8.0 Hz, 2 H), 7.64 (d, J = 8.0 Hz, 2 H), 7.26 (d, J = 8.0 Hz, 2 H), 3.17 (s, 1 H), 2.35 (s, 3 H)
ppm; FTIR (KBr): ν = 3295, 3110, 2918, 2861, 2198, 2192, 1601, 1568, 1522, 1484, 1466, 1415,
1402, 1365, 1294, 1217, 1184, 1144, 1060, 817, 725 cm−1. MALDI-TOF-MS (dithranol): m/z:
calcd for C17H13N3: 259.17 g mol−1, found: 259.31 g mol−1 [MH]+.
1-(4-Ethynyl-phenyl)-4-(4-propylphenyl)-1H-[1,2,3]triazole
The synthesized product as described in procedure C in a yield of (91%). 1H NMR (400 MHz,
CDCl3): δ = 8.14 (s, 1 H), 7.79 (d, J = 6.0 Hz, 2 H), 7.76 (d, J = 6.0 Hz, 2 H), 7.64 (d, J =
6.0 Hz, 2 H), 7.27 (d, J = 6.0 Hz, 2 H), 3.15 (s, 1 H), 2.61 (t, 2 H), 1.62 (m, 2 H), 0.89(t, 3 H)
ppm; FTIR (KBr): ν = 3293, 3111, 2913, 2860, 2198, 2190, 1611, 1568, 1522, 1484, 1466, 1415,
1402, 1365, 1293, 1217, 1184, 1144, 1060, 817, 726 cm−1. MALDI-TOF-MS (dithranol): m/z:
calcd for C19H17N3: 287.14 g mol−1, found: 287.26 g mol−1 [MH]+.
1-(4-Ethynyl-phenyl)-4-(4-pentylphenyl)-1 H-[1,2,3]triazole
The synthesized product as described in procedure C in a yield of (93%). 1H NMR (400 MHz,
CDCl3): δ = 8.14 (s, 1 H), 7.79 (d, J = 6.0 Hz, 2 H), 7.76 (d, J = 6.0 Hz, 2 H), 7.64 (d, J =
6.0 Hz, 2 H), 7.27 (d, J = 6.0 Hz, 2 H), 3.17 (s, 1 H), 2.62 (t, 2 H), 1.63 (m, 2 H), 1.33 (m, 2
H), 1.31 (m, 2 H), 0.88 (t, 3 H) ppm; FTIR (KBr): ν = 3294, 3111, 2913, 2861, 2198, 2190,
1601, 1568, 1522, 1484, 1466, 1415, 1402, 1365, 1293, 1217, 1184, 1144, 1060, 817, 724 cm−1.
MALDI-TOF-MS (dithranol): m/z: calcd for C21H21N3: 315.17 g mol−1, found: 315.4 g mol−1
[MH]+.
2-Fluoro-4-[4-(4-p-tolyl-[1,2,3]triazol-1-yl)-phenylethynyl]-benzonitrile (Procedure D)
1-(4-Ethynyl-phenyl)-4-(4-methyl-phenyl)-1H-[1,2,3]triazole (0.9 g, 3.5 mmol) and 2-
fluoro-4-iodo-benzonitrile (0.86 g, 3.5 mmol) were dissolved in 120 ml dry Et3N:THF (1:1)
in a 250 ml round-bottom flask. Add PdCl2(PPh3)2 (0.12 g, 0.16 mmol) and CuI (0.06 g,
0.32 mmol). The reaction mixture was then stirred at room temperature for 8 hr under an
Ar atmosphere. Upon completion, the solvent was removed in vacuo and the crude material
was purified by chromatography on silica gel (CH2Cl2) to give target compound (1.0 g, 79%)
as a white solid.
1H NMR (400 MHz, CDCl3): δ = 8.17 (s, 1 H), 7.84 (d, J = 8.0 Hz, 2 H), 7.80 (d, J = 8.0 Hz,
2 H), 7.70 (d, J = 8.0 Hz, 2 H), 7.61 (t, 1 H), 7.38 (m, 2 H), 7.27 (d, J = 6.0 Hz, 2 H), 2.39 (s, 3
H) ppm; FTIR (KBr): ν = 3112, 2923, 2852, 2235, 2207, 2190, 1604, 1568, 1522, 1484, 1466,
1415, 1402, 1368, 1293, 1207, 1183, 1144, 1060, 816, 721 cm−1. MALDI-TOF-MS (dithranol):
m/z: calcd for C24H15FN4: 378.19 g mol−1, found: 378.34 g mol−1 [MH]+.

178
Y.-Z. ZHAO ET AL.
2-Fluoro-4-(4-[4-(4-propyl-phenyl)-[1,2,3]triazol-1-yl]-phenylethynyl)-benzonitrile
The synthesized product as described in procedure D in a yield of (75%). 1H NMR (300 MHz,
CDCl3): δ = 8.17 (s, 1 H), 7.84 (d, J = 6.0 Hz, 2 H), 7.80 (d, J = 6.0 Hz, 2 H), 7.70 (d, J =
6.0 Hz, 2 H), 7.61 (t, 1 H), 7.38 (m, 2 H), 7.27 (d, J = 6.0 Hz, 2 H), 2.62 (t, 2 H), 1.65 (m, 2
H), 0.93 (t, 3 H) ppm; FTIR (KBr): ν = 3112, 2924, 2853, 2241, 2213, 1604, 1483, 1466, 1345,
1212, 1184, 995, 882, 800, 724 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C26H19FN4:
406.16 g mol−1, found: 406.30 g mol−1 [MH]+.
4-(4-Propyl-phenyl)-1-[4-(4-trifluoromethyl-phenylethynyl)-phenyl]-1H-[1,2,3]triazole
The synthesized product as described in procedure D in a yield of (75%). 1H NMR (300 MHz,
CDCl3): δ = 8.17 (s, 1 H), 7.82 (d, J = 6.0 Hz, 2 H), 7.80 (d, J = 6.0 Hz, 2 H), 7.70 (d, J =
6.0 Hz, 2 H), 7.64 (d, J = 6.0 Hz, 2 H), 7.61 (d, J = 6.0 Hz, 2 H), 7.26 (d, J = 6.0 Hz, 2 H), 2.62
(t, 2 H), 1.65 (m, 2 H), 0.95 (t, 3 H) ppm; FTIR (KBr): ν = 3101, 2921, 2853, 2209, 1606, 1584,
1523, 1466, 1404, 1363, 1325, 1273, 1183, 1144, 1062, 959, 814, 722 cm−1. MALDI-TOF-MS
(dithranol): m/z: calcd for C26H20F3N3: 431.16 g mol−1, found: 431.3 g mol−1 [MH]+.
2-Fluoro-4-(4-[4-(4-pentyl-phenyl)-[1,2,3]triazol-1-yl]-phenylethynyl)-benzonitrile
The synthesized product as described in procedure D in a yield of (80%). 1H NMR (300 MHz,
CDCl3): δ = 8.18 (s, 1 H), 7.84 (d, J = 6.0 Hz, 2 H), 7.80 (d, J = 6.0 Hz, 2 H), 7.70 (d, J =
6.0 Hz, 2 H), 7.61 (t, 1 H), 7.38 (m, 2 H), 7.27 (d, J = 6.0 Hz, 2 H), 2.63 (t, 2 H), 1.63 (m, 2
H), 1.61 (m, 2 H), 1.32 (m, 2 H), 0.88 (t, 3 H) ppm; FTIR (KBr): ν = 3116, 2923, 2852, 2239,
2211, 2190, 1604, 1568, 1522, 1484, 1466, 1415, 1402, 1368, 1293, 1207, 1183, 1144, 1060, 816,
720 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C28H23FN4: 434.19 g mol−1, found:
435.2 g mol−1 [MH]+.
4-(4-Pentyl-phenyl)-1-[4-(4-trifluoromethyl-phenylethynyl)-phenyl]-1H-[1,2,3]triazole
The synthesized product as described in procedure D in a yield of (76%). 1H NMR (300 MHz,
CDCl3): δ = 8.17 (s, 1 H), 7.82 (d, J = 6.0 Hz, 2 H), 7.80 (d, J = 6.0 Hz, 2 H), 7.70 (d, J =
6.0 Hz, 2 H), 7.64 (d, J = 6.0 Hz, 2 H), 7.61 (d, J = 6.0 Hz, 2 H), 7.27 (d, J = 6.0 Hz, 2 H),
2.63 (t, 2 H), 1.63 (m, 2 H), 1.33 (m, 2 H), 1.22 (m, 2 H), 0.88 (t, 3 H) ppm ; FTIR (KBr): ν
= 3113, 2924, 2851, 2213, 2191, 1603, 1568, 1522, 1484, 1466, 1412, 1402, 1368, 12935, 1207,
1183, 1144, 1063, 816, 723 cm−1. MALDI-TOF-MS (dithranol): m/z: calcd for C28H24F3N3:
459.19 g mol−1, found: 459.4 g mol−1 [MH]+.
Funding
This work was supported by the National Science Foundation of China (Grant 51173155) and the Major
Project of Beijing Science & Technology Program (Grant Z121100006512002).
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