Luminescent columnar liquid crystals based on 1,3,4-oxadiazole

Article abstract of DOI:10.1016/j.tet.2013.09.079

In this study five new compounds, derivatives of 1,3,4-oxadiazole, were synthesized in order to achieve mesomorphic behavior and luminescence. Different types of aliphatic chains were used in order to investigate the influence of alkoxide groups in mesomorphic behavior. All of the compounds showed high thermal stability and strong blue photoluminescence in solution and in solid films. Furthermore, compounds 10a-d presented hexagonal columnar mesomorphism, which was characterized by polarizing optical microscopy and X-ray diffraction, and strong π-stacking was observed. Notably, for two compounds (10c,d), the liquid crystal properties were preserved on cooling from the isotropic state to room temperature. These characteristics make these materials good candidates for application in organic electronics.

Full text of DOI:10.1016/j.tet.2013.09.079

Accepted Manuscript
Luminescent columnar liquid crystals based on 1,3,4-oxadiazole
Edivandro Girotto, Juliana Eccher, André A. Vieira, Ivan H. Bechtold, Hugo Gallardo
PII:
S0040-4020(13)01501-9
10.1016/j.tet.2013.09.079
TET 24854
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 6 August 2013
Revised Date: 20 September 2013
Accepted Date: 24 September 2013
Please cite this article as: Girotto E, Eccher J, Vieira AA, Bechtold IH, Gallardo H, Luminescent
columnar liquid crystals based on 1,3,4-oxadiazole, Tetrahedron (2013), doi: 10.1016/j.tet.2013.09.079.
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Luminescent columnar liquid crystals based
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Edivandro Girottoa, Juliana Eccherb, André A. Vieiraa, Ivan H. Bechtoldb and Hugo Gallardoa,*
aDepartamento de Química Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.
bDepartamento de Física, Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.

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Tetrahedron
journal homepage: www.elsevier.com
Luminescent columnar liquid crystals based on 1,3,4-oxadiazole
Edivandro Girottoa, Juliana Eccherb, André A. Vieiraa, Ivan H. Bechtoldb and Hugo Gallardoa,*
aDepartamento de Química Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.
bDepartamento de Física, Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
In this study five new compounds, derivatives of 1,3,4-oxadiazole, were synthesized in order to
achieve mesomorphic behavior and luminescence. Different types of aliphatic chains were used
in order to investigate the influence of alkoxide groups in mesomorphic behavior. All of the
compounds showed high thermal stability and strong blue photoluminescence in solution and in
solid films. Furthermore, compounds 10a-d presented hexagonal columnar mesomorphism,
which was characterized by polarizing optical microscopy and X-ray diffraction, and strong π-
stacking was observed. Notably, for two compounds (10c-d), the liquid crystal properties were
preserved on cooling from the isotropic state to room temperature. These characteristics make
these materials good candidates for application in organic electronics.
Available online
Keywords:
Synthesis
1,3,4-Oxadiazoles
Liquid crystals
Columnar mesomorphic
Luminescent
2009 Elsevier Ltd. All rights reserved
.
Introduction
molecular shapes, such as rod-like13, dimers14, polymers15, 1,3,4-
oxadiazole-based polycatenar16, and star-shaped17, and also bent-
core LCs, have been reported18. Oxadiazole molecules are among
the most widely investigated as electroluminescent materials and
as electron-transport materials in OLEDs15, where a series of
compounds containing the 1,3,4-oxadiazole ring, such as the
compound 2,5-bis(4-naphthyl)-1,3,4-oxadiazole, has become one
of the top organic electron conductors16.
In this paper, we report the synthesis of new compounds,
based on a 1,3,5-trisubstituted benzene core with three-fold
symmetry using three 1,3,4-oxadiazolearms, with a total of six
peripheral aliphatic chains attached to the three terminal benzene
rings. Their mesophase behavior was studied by differential
scanning calorimetry, polarizing optical microscopy and X-ray
diffraction, which revealed mainly enantiotropic hexagonal
columnar phases. However, the compounds containing six free
hydroxyl groups at the end of the alkyl chain did not exhibit
liquid crystalline properties. All compounds possess pronounced
blue emission in solution and as thin films. For the films, the
emission was also investigated as a function of the temperature,
where a strong dependence with the mesophase was observed.
Since the first report of discotic liquid crystals (DLCs) by
Chandrasekhar et al. in 19771, the synthesis and study of these
materials have been increasing exponentially, due to their great
potential for application in organic devices2. DLCs are suitable
for technological applications owing to the fact that these disc-
shape compounds can self-assembly into molecular stacks,
forming columns through π-π stacking interactions3. The
formation of these molecular columns leads to interesting
properties, such as the formation of a semiconductor with
unidimensional electrical properties, similar to a nanowire, where
the aromatic rigid center acts as conducting core and the aliphatic
chains function as an insulator around the semiconductor,
increasing the efficiency of the charge-carrier mobility4.This
makes DLCs promising candidates for application in organic
electronic devices, such as organic light-emitting diodes
(OLEDs)2c,5,organic photovoltaic cells (OPVs)6 and organic field-
effect transistors (OFETs)7.
Liquid crystals offer many possibilities for their
functionalization through hydrogen bonds leading to self-
organized systems8, arrangements with strong π-conjugation,
which may promote luminescence, and the introduction of
heterocyclic groups, which have a strong influence on their
physical properties and mesomorphic behavior9. Liquid crystals
incorporating the 1,3,4-oxadiazole heterocycle have received
significant attention since the first reports of their mesomorphic
properties10. They have become good candidates for application
in organic electronics11 due to high fluorescence quantum yields,
charge carrier mobility and good chemical and thermal stability12.
Thus, in recent years, various liquid crystals based on different
Experimental Section
Measurements and Characterization.1H and 13C NMR spectra
were obtained with a Varian Mercury Plus 400 MHz instrument
using tetramethylsilane (TMS) as the internal standard. Infrared
spectra were recorded on a Perkin-Elmer model 283 spectrometer
using KBr disks or films. Mass spectra were recorded on a
Bruker Autoflex III Smart bean with MALDI-TOF techniques,
using α-cyano-4-hydroxycinnamic acid as the matrix, and high

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resolution mass spectra were recorded on a Bruker micrOTOF-
The relative fluorescence quantum yields (ФFI) were
Q II APCI-Qq-TOF mass spectrometer.
determined according to a published method20. The absorption
and fluorescence measurements for thin solid films were
collected on an OceanOptics (USB4000) spectrophotometer.
For the absorption, spin-coated films were prepared on quartz
glass plates with a concentration of 10 mg/ml, at 3000 rpm for
30s. To investigate the photoluminescence as a function of the
temperature the same samples used for the XRD were placed on a
hot stage, illuminated with a UV lamp and the emission was
captured with an optic fiber positioned close to the film.
Cyclic voltammetry analysis was performed to determine the
highest occupied molecular orbital (HOMO) and the lowest
unoccupied molecular orbital (LUMO). A three-electrode cell
was used, comprised of a glassy carbon electrode as the working
electrode, a platinum wire as the counter electrode, an Ag+/AgCl
electrode as the reference and the ferrocene/ferrocenium (Fc/Fc+)
redox couple as an internal standard. Before each measurement,
the cell was deoxygenated by purging with nitrogen.
Electrochemical measurements, using cyclic voltammetry, were
performed on an Autolab PGSTAT128N potentiostat/galvanostat
(Eco Chemie, The Netherlands) connected to data processing
software (GPES, software version 4.9.007, Eco Chemie).
The textures of the mesophases were captured with polarizing
optical microscopy (POM) using an Olympus BX50 microscope
equipped with a Mettler Toledo FP-82 hot stage and a PM-30
exposure control unit. Thermal transitions and enthalpies were
determined by differential scanning calorimetry (DSC) using the
DSC-Q 2000 calorimeter. Thermo gravimetric analysis (TGA)
was carried out using a Shimadzu analyzer with the TGA-50
module. Elemental analysis was carried out using a Carlo Erba
(model E-1110) instrument.
The X-ray diffraction (XRD) experiments were carried out on
an X`Pert-PRO (PANalytical) diffractometer using the linear
monochromatic Cu Kα beam (Ȟ = 1.5405 Å), with an applied
power of 1.2 kVA. The samples were prepared using procedures
described in the literature19 with the heating and cooling of an
amount of powder on glass plates. The scans were performed in
continuous mode from 2o to 30o (2θ angle) with the samples in
the mesophase, obtained by cooling from the isotropic state. The
absorption spectra in solution were obtained with an HP UV-
Vis model 8453 spectrometer. The fluorescence spectra in
solution were recorded on a Hitachi-F-4500
.
Scheme 1. Synthesis of bromide 3 and protection of compound 5.
Scheme 2. Synthesis of target compounds 10a-d, f.

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The synthesis began with the preparation of two non-
commercial bromides. The first compound was obtained starting
from themethyl 4-(dodecyloxy)benzoate 1, previously alkylated,
which was reduced using NaBH4 in dry methanol to give the
benzyl alcohol 2. This, in turn, was reacted with PBr3 to obtain
the 1-(bromomethyl)-4-(dodecyloxy)benzene 3. In addition, the
hydroxyl group of 11-bromoundecan-1-ol 4 was protected via the
acetyl group by heating with acetic anhydride to give the bromide
5 (Scheme 1).
amongst all derivatives synthesized in this work. The enthalpy
values from the columnar to isotropic phase of the compounds
10a-d were between ∆H = 1.5-7.6 kJ/mol and suggest a high
mesophase stability, based on the existence of strong interdisc
core-core π interactions. Comparing the transition temperatures
of compounds 10a, 10b and 10c reveals that it is possible to
modulate the mesomorphic range of the same columnar phase
simply by using different terminal alkyl chains (straight and
branched).
The synthetic route adopted for the preparation of the final
compounds derived from 1,3,4-oxadiazole heterocyclic is shown
in Scheme 2. Initially, with compound 6, alkylation reactions
were carried out using different bromides 3, 5, 1-bromoundecane,
3-(bromomethyl)heptane and (S)-8-bromo-2,6-dimethyloct-2-ene
and employing potassium carbonate and butanone under reflux8.
After obtaining the nitriles 7a-e, these compounds were reacted
with sodium azide and ammonium chloride in DMF to generate
the corresponding tetrazoles 8a-e through the Tiemann reaction21.
Following the synthetic route, the benzene-1,3,5-tricarboxylic
acid was converted to its corresponding acid chloride with
thionyl chloride and then immediately reacted with the tetrazoles
8a-e in dry pyridine under reflux to afford the final compounds
10a-d. The reaction applied to obtain the heterocyclic 1,3,4-
oxadiales is followed by the intense liberation of nitrogen gas,
which is characteristic of the Huisgen reaction22. The 10e
molecule, with the acetyl group, was not isolated. After
preparation, this compound was directly deprotected, remaining
six free hydroxyl groups at the end of the alkyl chain. The
hydrolysis reaction was carried out using sodium hydroxide in
EtOH/H2O to obtain the respective compound 10f. All
The molecule 10d, containing 4-dodecyloxybenzyl groups as
substituents, does not present crystallization on cooling cycle. On
microscope, this compound shows liquid-crystalline behavior at
room temperature, but does not present any characteristic texture
itself. When cooled down from the isotropic liquid, it shows
characteristic broken fan and mosaic textures of discotic
columnar phases. The DSC thermogram displays two soft solid
transitions followed by another one representing the transition
from columnar phase to isotropic liquid on heating. Upon
cooling, it shows only the transition from isotropic liquid to
columnar phase, remaining stable in this phase until room
temperature.
The thermal stability of the final compounds 10a-d and 10f
was studied by TGA under nitrogen atmosphere. Compound 10d
o
showed decomposition onset at 368 C while for all of the other
compounds the corresponding temperature was above 400 oC
(see supporting information).
Figure 1. Optical photomicrographs of different colh phases under crossed
polarizers: (a) focal conic for 10a at 151 °C, (b) pseudo focal conic for 10b at
90 °C, (c) mosaic textural pattern for 10c at 25 °C and (d) rectilinear defects
for 10d at 172 °C.
1
compounds synthesized were characterized by H and 13C NMR
and IR spectroscopy. Also, the final compounds were
characterized by MALDI-MS (see supporting information).
Results and discussion
Mesomorphic Properties. The phase transition temperatures
of all of the compounds (10a–d, f) were initially established by
POM and then accurately measured by DSC. The DSC results
with their associated enthalpy changes are given in Table 1. The
thermal parameters are taken from the first heating−cooling
cycles of DSC scans. With the exception of 10f, all compounds
exhibited mesomorphic behavior, exclusively hexagonal
columnar (Colh), identified by the typical optical textures, where
on cooling a dendritic growth from the isotropic liquid and a
combination of mosaics with linear and fan shaped birefringent
defects, together with homeotropic regions, were observed
through POM, as seen in Figure 1. The Colh mesophases were
later confirmed via XRD experiments. Compound 10f did not
show liquid crystalline phases, it melted directly into the
isotropic liquid state at 109-110 °C, and on cooling, the sample
crystallizes. The lack of mesomorphism is probably due to the
free hydroxyl group at the end of the alkyl chain, which hinders
the mesomorphic behavior even for a stable columnar liquid
crystal23.Using the same number of substituents but with different
alkoxy chains a considerable variation was observed in the
thermal behavior of the respective liquid-crystalline materials.
Compound 10b with branched chains, compared with 10a which
contains 12 carbon atoms in a straight chain, showed the lowest
melting point at 81 °C and the lowest mesomorphic range of the
series (∆ = 52.4°C). Furthermore, compounds 10a and 10b
showed crystallization on cooling to 77.7 °C and 38.2 °C,
respectively. The compound 10c shows only one transition
(Colh–I) at 116.1 °C during heating and one transition (I–Colh) at
104.9 °C during cooling, which is the widest mesophase range
Table 1. Phase transitions and enthalpies (kJ/mol) of
compounds 10a-d.
XRD data
Compound
Phase transition profilea
Cr 103.1 (54.4) Colh 183.7 (3.9) I
I 181.0 (5.6) Colh 77.7 (5.6) Cr
Cr 81.1 (6.4) Colh 108.3 (1.9) I
I 90.6 (1.3) Colh 38.2 (0.7) Cr
Colh 116.1 (1.5) I
T (oC)
ab (Å)
10a
170
35.9
10b
10c
10d
90
30
28.1
31.2
47.9
c
I 104.9 (0.9) Colh
ss 78.0 (0.4) ss 132.0 (3.1) Col 235.7 (8.4) I
120
c
I 231.8 (7.6) Colh
Transition temperatures (°C) and in parentheses the transition enthalpies
(kJ/mol), determined by DSC during heating (first line) and cooling (second
line) cycles. ss = soft solid; Cr = crystalline; Colh = columnar hexagonal; I =
b
isotropic liquid. Intercolumnar distance. c The Colh phase did not crystallize
upon cooling down to −50 °C.

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X-ray diffraction studies. The molecular organization
Cyclic voltammetry measurements were performed on compound
observed by POM was confirmed by XRD experiments for
compounds 10a-d and the diffraction peaks indexed by the Miller
indices. All of the compounds presented an intense diffraction
peak at the low angle region (100) and some of them also showed
peaks at 110 and 200. It is well known that for colh phases the
ratio between these peaks should be1: √3: √423, as demonstrated
here in. In addition, a diffuse peak relative to the liquid-like order
of the peripheral alkoxybenzyl groups was observed at around
4.6 Å and the peak at around 3.4 Å indicates a periodic
intracolumnar spacing between neighboring discs. This is of
particular interest for electronic applications due to the close π-
staking2c,24 and contributes to the stability of the mesophase. In
10c, which presents an enantiotropic colh mesophase which is
preserved until room temperature during cooling.
This
characteristic is important for practical applications in
electronics, where annealing processes can be used to obtain
macroscopic molecular ordering. Based on the optical band gap
obtained from the absorption spectrum (Egap = 3.80 eV) it was
possible to determine the HOMO = -5.21 eV and LUMO = -1.41
eV electronic orbitals (for more details see supporting
information).
o
Figure 2, the XRD spectrum of compound 10c at 30 C shows
that the hexagonal order is preserved until room temperature
without crystallization. The XRD spectra of the other
mesomorphic compounds are presented in the supporting
information, together with the lattice parameters.
The intercolumnar distances (a) presented in Table 1 were
obtained from XRD data according to reports in the literature25.
The molecular diameters of compounds 10a, 10b, 10c and 10d
(47.5 Å, 31.9 Å, 37.7 Å and 55.8 Å) were estimated using
ChemBio3D Ultra Software, version 11.0.1.The fact that these
values are between 11.6 Å and 3.8 Å (for compounds 10a and
10b, respectively) larger than a suggest that all of the compounds
present interdigitation of the alkoxy chains or non linear
conformations. This may explain the reason why compound 10e
does not present mesomorphic behavior. The OH groups at the
end of aliphatic chains probably form hydrogen bonds with the
terminal OH groups, which prevents interdigitation of the chains
and consequently the columnar phase.
Figure 3. Optical absorption and fluorescence spectra obtained for the final
compounds 10a-e, in chloroform solution (10-5 M).
Table 2. Optical data for compounds 10a-d, f in chloroform
solution (10-5 M).
Absorptiona
327
Emissionb
413
Stokes Shift
φF
c
Compound
10a
86
82
84
83
84
0.57
0.63
0.59
0.47
0.55
10b
329
411
10c
326
410
10d
323
406
10f
327
411
a 10-5 M in chloroform at 20 °C, b Excitation wavelength at λ max of
absorption, c Quantum yield relative to quinine sulfate.
The photophysical properties of these compounds were also
studied in solid films. The maximum absorption wavelengths of
compounds 10c-d are blue-shifted compared to those in solution,
as is commonly observed for thin solid films28,29, but without
significant changes in the shape of the absorption spectra. On the
other hand, for compounds 10a,b the wavelength of maximum
absorption was preserved but with the appearance of a shoulder
at lower wavelengths (see supporting information). The emission
was captured as a function of the temperature using the same
samples employed in the XRD analysis. All final compounds
displayed strong luminescence in the range of 400-550 nm when
excited with UV-light, most of them demonstrating bathochromic
shifts compare to the emission in solution. The emission spectra
for compound 10b as a function of the temperature are shown in
Figure 4a. Several spectra were collected by heating the sample
from the crystal to the isotropic phase. Changes in the shape of
the profile are commonly observed and are well described in the
litterature24. The diminution in the maximum emission intensity
on increasing the temperature (see Figure 3b) is expected for
semiconducting materials and is associated with thermally
Figure 2. XRD pattern obtained for compound 10c in the Colh
phase at 30 °C.
Optical Properties. The UV–Vis absorption and fluorescence
spectra of 10a-d, f in chloroform solution are presented in Figure
3 and the data are summarized in Table 2. As expected, the
changing of the alkoxy chains did not affect the electronic
properties of these materials, and the absorption and emission
spectra show similar profiles. The maximum absorption
wavelength (Ȟ máx) of the final compounds in solution varied
from 323 to 329 nm. These compounds presented a strong blue
emission under UV-light with maxima at around 410 nm. These
materials exhibited good quantum yields of between 0.47-0.63 in
relation to quinine sulfate26.The high molar absorption coefficient
(
≈ 47.000L mol-1 cm-1) for these compounds is attributed to the
π−π* transitions from the heterocyclic 1,3,4-oxadiazole
portion17, 27.The Stokes shift for these molecules is approximately
84 nm in solution.

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activated non-radioactive decay processes23, 30. Compounds 10a,
References
10c and 10d presented similar behavior (see supporting
information).
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Conclusions
A new series of compounds derived from the 1,3,4-oxadiazole
heterocyclic was designed and synthesized. Four compounds
presented liquid crystalline properties with hexagonal columnar
mesomorphism and good thermal stability. The mesomorphic
properties are closely dependent on the aliphatic chains
connected to the rigid disc-like core (their chirality and the
presence of OH groups). For compounds 10c and 10d the
hexagonal columnar phase was preserved until room temperature
with no evidence of crystallization. All of them presented intense
blue photoluminescence in solution and in solid films. These
characteristics together with the strong overlapping π molecular
orbitals make these materials good candidates for applications in
organic electronic devices.
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The authors are grateful to the Brazilian governmental
agencies CNPq, CAPES, INCT/INEO, INCT-Catálise and
PRONEX/FAPESC for financial support. The XRD experiments
were carried out in the Laboratório de Difração de Raios-X
(LDRX-CFM/UFSC).

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T., Mesomorphism and Luminescence Properties of Platinum(II)

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7
Tables
Table 1. Phase transitions and enthalpies (kJ/mol) of
compounds 10a-d.
XRD data
Compound
Phase transition profilea
Cr 103.1 (54.4) colh 183.7 (3.9) I
I 181.0 (5.6) colh 77.7 (5.6) Cr
Cr 81.1 (6.4) colh 108.3 (1.9) I
I 90.6 (1.3) colh 38.2 (0.7) Cr
colh 116.1 (1.5) I
T (oC)
ab (Å)
10a
170
90
35.9
10b
10c
10d
28.1
31.2
47.9
30
c
I 104.9 (0.9) colh
ss 78.0 (0.4) ss132.0 (3.1) Col 235.7 (8.4) I
I 231.8 (7.6) Colhc
120
Transition temperatures (°C) and in parentheses the transition enthalpies
(kJ/mol), determined by DSC during heating (first line) and cooling (second
line) cycles. ss = soft solid; Cr = crystalline; colh = columnar hexagonal; I =
b
isotropic liquid. Intercolumnar distance. c The Colh phase did not crystallize
upon cooling down to −50 °C.
Table 2. Optical data for compounds 10a-e in chloroform solution (10-5 M).
c
Compound
10a
Absorptiona
Emissionb
Stokes Shift
φF
327
413
86
82
84
83
84
0.57
0.63
0.59
0.47
0.55
10b
329
411
10c
326
410
10d
323
406
10e
327
411
a 10-5 M in chloroform at 20 °C, b Excitation wavelength at λ max of
absorption, c Quantum yield relative to quinine sulfate.
Legends for Figures
Figure 1. Optical photomicrographs of different colh phases
under crossed polarizers: (a) focal conic for 10a at 151 °C, (b)
pseudo focal conic for 10b at 90 °C, (c) mosaic textural
pattern for 10c at 25 °C and (d) rectilinear defects for 10d at
172 °C.
Figure 2. XRD pattern obtained for compound 10c in the Colh
phase at 30 °C.
Figure 3. Optical absorption and fluorescence spectra
obtained for the final compounds 10a-d, f, in chloroform
solution (10-5 M).
Figure 4. a) Emission spectra of compound 10b recorded
during heating from crystal to the isotropic phase. (b)
Maximum intensity as a function of the temperature
Legends for Schemes
Scheme 1. Synthesis of bromide 3 and protection of
compound 5.
Scheme 2. Synthesis of target compounds 10a-d, f.

ACCEPTED MANUSCRIPT
Supporting Information
Luminescent Columnar Liquid Crystals Based on
1,3,4-oxadiazole
Edivandro Girottoa, Juliana Eccherb, André A. Vieiraa, Ivan H. Bechtoldb and Hugo
Gallardoa,*
aDepartamento de Química Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.
bDepartamento de Física, Universidade Federal de Santa Catarina, Florianópolis-SC, 88040-900, Brazil.
*Email: hugo@qmc.ufsc.br; fax: +55 48 37216850; tel: +55 48 37219544
Experimental
Methyl p-(dodecyloxy)benzoate (1). 4.0 g ( 26 mmol) of methyl 4-hydroxybenzoate, 7.17
g (52 mmol) of K2CO3, 7.17 g (29 mmol) of 1-bromododecane and 150 mL of butanone
were refluxed for 24h. The suspension was filtered and washed twice with hot butanone.
The solvent was removed by rotary evaporation and the solid was recrystallized with
o
ethanol and water, resulting in 7.5 g of a white solid. Yield 90%. Mp: 54.0-56.2 C. IR
(KBr pellet) νmaxcm-1: 2955, 2849, 1725, 1609.1H NMR (400 MHz, CDCl3) δ ppm: 7.98 (d,
J = 8.9 Hz, 2H, Ar-H), 6.80 (d, J = 8.9 Hz, 2H, Ar-H), 4.0 (t, J = 6.4 Hz, 2H, O-CH2), 3.88
(s, 3H, -COO-CH3),1.79 (m, 2H, -CH2),1.43 (m, 2H, -CH2), 1.26 (m, 16H, -CH2), 0.88 (t, J
= 6.8 Hz, 3H, -CH3).13C NMR (CDCl3), δ, ppm: 166.9, 131.5, 122.3, 114.0, 68.2, 51.8,
31.9, 29.6, 29.6, 29.6, 29.4, 29.1, 22.7, 14.1.
p-(Dodecyloxy)benzylalcohol (2). Under argon atmosphere, 1.4 g (34 mmol) of LiAlH4
was added in 100 mL of dry THF and the mixture was cooled to -5 oC. Compound 1 (7.30
g (23 mmol)) was dissolved in 70 mL of dry THF, and added slowly dropwise for 1h.
Then, the solution temperature was raised until room temperature and kept steering for
more 3h. 30 mL of ethanol was carefully added dropwise in the reaction and the solvent
removed by rotary evaporation. The solid was dissolved in ethyl acetate and the white

ACCEPTED MANUSCRIPT
suspension was filtrated. The solvent was removed by rotary evaporation and 6.0 g of a
o
white solid was obtainded. Yield 90%. Mp: 65.2-67.0 C. IR (KBr pellet) νmaxcm-1: 3322,
2955, 2849, 1614, 1584. 1H NMR (400 MHz, CDCl3), δ, ppm: 7.28 (d, J = 8.6 Hz, 2H, Ar-
H), 6.80 (d, J = 8.6 Hz, 2H, Ar-H), 4.61 (s, 2H, -CH2-OH), 3.95 (t, J = 6.5 Hz, 2H, -O-
CH2), 1.78 (m, 2H, -CH2), 1.45 (m, 2H, -CH2), 1.26 (m, 16H, -CH2), 0.88 (t, J = 6.8 Hz,
3H, -CH3).13C NMR (CDCl3), δ, ppm: 158.8, 132.8, 128.8, 114.5, 68.0, 65.1, 31.9, 29.7
29.6, 29.6, 29.4, 29.2, 26.0, 22.7, 14.1.
1-(Bromomethyl)-4-(dodecyloxy)benzene (3). A solution of 7.7 g (21 mmol) of
compound 2 in 20 mL of 48% bromic acid and 20 mL of THF was stirred at room
temperature for 3h. The resulting solution was extracted with chloroform (3 x 40 mL). The
separated organic phase was washed with saturated aqueous NaHCO3, dried with CaCl2
and the solvent was removed by rotary evaporation to give 7.4 g of compound 3. Yield
o
1
96%. Mp: 40.0-43.0 C. IR (KBr pellet) νmax cm-1: 2953, 2918, 2849, 1609. H NMR (400
MHz, CDCl3), δ, ppm: 7.31 (d, J = 8.4 Hz, 2H, Ar-H), 6.85 (d, J = 8.4 Hz, 2H, Ar-H), 4.50
(s, 2H, Ar-CH2-Br), 3.95 (t, J = 6.4 Hz, 2H, O-CH2), 1.77 (m, 2H, -CH2), 1.44 (m, 2H, -
CH2), 1.27 (m, 16H, -CH2), 0.88 (t, J = 6.8 Hz, 3H, -CH3). 13C NMR (CDCl3), δ, ppm:
159.2, 130.4, 129.6, 114.7, 68.1, 34.1, 31.9, 29.6, 29.6, 29.6, 29.4, 29.3, 29.2, 26.0, 14.1.
11-Bromoundecyl acetate (5). A solution of 3.0 g (12 mmol) of 11-bromoundecan-1-ol, 4
mL (42 mmol) of pyridine and 4 mL (42 mmol) of acetic anhydride was refluxed for 3h.
The solution was then added in 150 mL of water/ice, acidified to pH 2 with HCl aqueous
solution (15%). The organic phase was separated and the aqueous phase extracted with
CH2Cl2 (3 x 40 mL), and dried with anhydrous Na2SO4. The organic solvent was removed
by rotary evaporation and 3.4 g of a colorless oil was obtained. Yield 97%. IR (KBr pellet)
νmaxcm-1: 2927, 2855, 1740.1H NMR (400 MHz, CDCl3), δ, ppm: 4.01 (t, J = 6.8 Hz, 2H, -
COO-CH2), 3.36 (t, J = 6.8 Hz, 2H, Br-CH2), 2.00 (s, 2H, -COOCH3), 1.81, 1.57, 1,38 (m,
6H, -CH2), 1.24 (m, 14H, -CH2). 13C NMR (CDCl3), δ, ppm: 187.4, 171.4, 64.8, 34.2, 33.0,
29.6, 29.6, 29.6, 29.4, 29.0, 28.8, 28.4, 26.1.
3,4-Bis(dodecyloxy)benzonitrile (7a). 3.0 g (22 mmol) of compound 6, 15.3 g (111
mmol) of K2CO3, 12.1 g (49 mmol) of 1-bromododecane, 0.4 g (1 mmol) of TBAB and
150 mL of butanone were refluxed for 24h. The suspension was filtered and washed twice
with hot butanone. The solvent was removed by rotary evaporation and the solid
recrystallized with ethanol and water, and a 9.2 g of a white solid was obtained. Yield

ACCEPTED MANUSCRIPT
89%. Mp: 75-81 oC. IR (KBr pellet) νmaxcm-1: 2955, 2917, 2850, 2873, 2850, 2221, 1597. 1H
NMR (400 MHz, CDCl3), δ, ppm: 7.24 (dd, J = 8.2, 1.7 Hz, 1H, Ar-H), 7.02 (d, J = 1.7
Hz, 1H, Ar-H), 6.87 (d, J = 8.2 Hz, 1H, Ar-H), 4.50 (t, J = 6.2, 2H, OCH2), 3.98 (t, J =
6.6 Hz, 2H, O-CH2), 1.83 (m, 4H, -CH2), 1.46 (m, 4H, -CH2), 1.27 (m, 32H, -CH2), 0.88 (t,
J = 6.8 Hz, 6H, -CH3). 13C NMR (CDCl3), δ, ppm: 153.02, 149.0, 126.2, 119.4, 115.9,
112.6, 103.4, 69.3, 69.0, 31.9, 29.6, 29.6, 29.5, 25.6, 29.3, 28.9, 22.6, 14.1.
3,4-Bis(2-ethylhexyloxy)benzonitrile (7b). The same procedure used to obtain compound
7a was applied. The compound was purified by column chromatography using
hexane/ethyl acetate (80:20) as the eluent, resulting in 2.5 g of an oil. Yield 89%. IR (KBr
pellet) νmaxcm-1: 2958, 2926, 2877, 2225, 1598.1H NMR (400 MHz, CDCl3), δ, ppm: 7.23
(dd, J = 8.4, 1.5 Hz, 1H, Ar-H), 7.06 (d, J = 1.6 Hz, 1H, Ar-H), 6.87 (d, J = 8.4 Hz, 1H,
Ar-H), 3.90 (m, 4H, O-CH2), 1.75 (m, 2H, -CH), 1.48 (m, 8H, -CH2), 1.31 (m, 8H, -CH2),
0.93 (m, 12H, -CH3). 13C NMR (CDCl3), δ, ppm: 153.4, 149.4, 126.1, 119.5, 115.6, 112.4,
103.3, 71.6, 71.3, 39.3, 30.5, 29.0, 23.9, 23.0, 14.0, 11.1.
3,4-Bis((S)-3,7-dimethyloct-6-enyloxy)benzonitrile (7c). The same procedure used to
obtain compound 7a was applied. The compound was purified by column chromatography
using hexane/ethyl acetate (95:5) as the eluent, resulting in 2.4 g of an oil. Yield 96%. IR
(KBr pellet) νmaxcm-1: 2964, 2926, 2877, 2224, 1598. (400 MHz, CDCl3), δ, ppm: 7.24
(dd, J = 8.4, 1.8 Hz, 1H, Ar-H), 7.07 (d, J = 1.8 Hz, 1H, Ar-H), 6.88 (d, J = 8.4 Hz, 1H,
Ar-H), 5.09 (m, 2H, CH), 4.06-4.01 (m, 4H, O-CH2), 2.00-1.88 (m, 8H, -CH2), 1.68-1.60
(m, 12H, -CH3), 1.39-1.25 (m, 6H, -CH2), 0.97-95 (m, 6H, -CH3). 13C NMR (CDCl3), δ,
ppm: 153.0, 149.0, 126.3, 124.6 119.5, 115.8, 112.6, 103.5, 67.6, 67.4, 37.1, 35.8, 29.6,
25.7, 19.6, 17.7
.
3,4-Bis(4-(dodecyloxy)benzyloxy)benzonitrile (7d). The same procedure used to obtain
compound 7a was applied. The crude solid was purified and recrystallized in ethanol,
o
resulting in 6.2 g of a yellow solid. Yield 88%. Mp: 124-127 C. IR (KBr pellet) νmaxcm-1:
2954, 2920, 2850, 2219, 1615. (400 MHz, CDCl3), δ, ppm: 7.31 (d, J = 8.4 Hz, 4H, Ar-H),
7.21 (dd, J = 8.6, 1.9 Hz, 2H, Ar-H), 7.13 (d, J = 1.9 Hz, 2H, Ar-H), 6.94 (d, J = 8.6 Hz,
2H, Ar-H), 6.89 (d, J = 8.4 Hz, 4H, Ar-H), 5.11 (s, 2H, Ar-CH2), ), 5.06 (s, 2H, Ar-CH2),
3.95 (m, 4H, O-CH2), 1.78 (m, 4H, -CH2), 1.48 (m, 4H, -CH2), 1.26 (m, 28H, -CH2), 0.88
(m, J = 6.8, 6H, -CH3). 13C NMR (CDCl3), δ, ppm: 159.2, 152.9, 148.8, 129.0, 128.9,
127.9, 127.7, 126.7, 119.2, 117.8, 114,6, 114.1, 104.0, 71.3, 152.9, 148.8, 129.0, 128.9,

ACCEPTED MANUSCRIPT
127.9, 127.7, 126.7, 119.2, 117.46, 114.6, 104.0, 71.3, 70.8, 68.0, 31.9, 29.7, 29.6, 29.4,
29.3, 29.2, 26.0, 22.7, 14.1.
11,11'-(4-Cyano-1,2-phenylene)bis(oxy)bis(undecane-11,1-diyl) diacetate (7e). The
same procedure used to obtain compound 7a was applied. The solid was purified by
column chromatography using CH2Cl2/ethanol (97:3) as the eluent, resulting in 1.8 g of a
o
yellow solid. Yield 73%. Mp: 108-111 C. IR (KBr pellet) νmaxcm-1: 2916, 2870, 2850,
2220, 1742, 1597. (400 MHz, CDCl3), δ, ppm: 7.24 (dd, J = 8.3, 1.8 Hz, 1H, Ar-H), 7.06
(d, J = 1.8 Hz, 1H, Ar-H), 6.8 (d, J = 8.3 Hz, 1H, Ar-H), 4.05 (s, 4H, COO-CH2), 3.98
(m, 4H, O-CH2), 2.04 (s, 4H, -CH3), 1.83 (m, 4H, -CH2), 1.46 (m, 4H, -CH2), 1.28 (m,
30H, -CH2). 13C NMR (CDCl3), δ, ppm: 171.5, 153.2, 119.2, 126.5, 119.7, 116.2, 112.9,
103.7, 69.6, 69.3, 66.9, 29.7, 29.6, 29.5, 29.2, 29.2, 28.8, 26.1, 21.3.
General procedure for the synthesis of compounds (8a-e). 8g (17 mmol) of compound 7a,
4.4 g (68 mmol) of NaN3 and 3.6 g (68 mmol) in 70 mL DMF were refluxed for 24h. The
suspension was cooled to room temperature and poured in 300 mL of ice/water and
acidified to pH 2 with HCl aqueous solution (15%). The solid was filtrated and washed
with water and recrystallized in iso-propanol, resulting in 7.6 g of compound 8a.Yield
o
1
87%. Mp: 157 C. IR (KBr pellet) νmaxcm-1: 2921, 2850, 2800-2500, 1609. H NMR (400
MHz, Pyridine-d6 (90 0C), δ, ppm. 8.01 (s, 1H, Ar-H), 7.99 (s, 1H, Ar-H), 7.19 (s, 1H, Ar-
H), 4.39 (t, 2H, O-CH2), 3.99 (t, 2H, O-CH2), 1.82 (m, 2H, -CH2-), 1.50 (m, 2H, -CH2-),
0
1.27 (m, 36H), 0.80 (m, 6H, CH3, CH2). 13C NMR (Pyridine-d6 (90 C)), δ, ppm: 157.9,
152.4, 121.3, 118.8, 114.5, 113.1, 69.7, 32.6, 30.1, 29.9, 23.4, 14.8.
5-(3,4-Bis(2-ethylhexyloxy)phenyl)-2H-tetrazole (8b). The oil was purified by column
chromatography using hexane/ethyl acetate (95:5) as the eluent, resulting in 1.8 g of 8b.
1
Yield 92%. IR (KBr pellet) νmaxcm-1: 2966, 2916, 2876, 1609, 1516. H NMR (400 MHz,
CDCl3), δ, ppm: 7.66 (d, J = 8.2 Hz, 1H, Ar-H), 7.64 (s, 1H, Ar-H), 6.90 (d, J = 8.2 Hz,
1H, Ar-H), 3.84 (s, 4H, O-CH2), 1.75, 1.69 (m, 2H, -CH2), 1.43 (m, 4H, -CH2),1.29, 1.25
(m, 12H, -CH2), 0.93, 0.84 (mt, 12H, -CH3); 13C NMR (CDCl3), δ, ppm: 153.3, 150.0,
120.5, 115.5, 112.6, 111.6, 105.0, 71.4, 39.4, 30.5, 29.1, 23.8, 23.0, 14.0, 11.1.
5-(3,4-Bis((S)-3,7-dimethyloct-6-enyloxy)phenyl)-2H-tetrazole (8c). This compound
o
was obtained as a white solid and no purification was required. Yield 88%. Mp: 86-88 C.

ACCEPTED MANUSCRIPT
1
IR (KBr pellet) νmaxcm-1: 2966, 2916, 2993, 2639, 1609. H NMR (400MHz, CDCl3), δ,
ppm: 7.69 (d, J = 8.2 Hz, 1H, Ar-H),7.68 (s, 1H, Ar-H), 6.96 (d, J = 8.2 Hz, 1H, Ar-H),
5.07 (m, 2H, =CH), 4.06 (s, 4H, O-CH2),1.95, 1.85 (m, 4H, -CH2),1.65, 1.57 (m, 12H, -
CH3), 1.36, 1.19 (m, 10H, -CH2), 0.95, 0.90 (m, 6H, -CH3). 13C NMR (CDCl3), δ, ppm:
151.9, 149.6, 131.3, 131.2, 126.6, 120.7, 115.5, 113.1, 111.9, 67.5, 37.2, 36.0, 29.7, 25.7,
25.5, 19.5, 17.6.
5-(3,4-Bis(4-(dodecyloxy)benzyloxy)phenyl)-2H-tetrazole (8d). The compound was
recrystallized in ethanol and a light brown solid was obtained. Yield 91%. Mp: 137-139
124-127 oC. IR (KBr pellet) νmaxcm-1: 3076, 2955, 2919, 1850, 2734-2481, 1610. 1H NMR
(400 MHz, CDCl3), δ, ppm: 7.66 (s, 1H, Ar-H), 7.53 (d, J = 8.4 Hz, 1H, Ar-H), 7.30 (d, J =
8.6 Hz, 4H, Ar-H), 7.00 (d, J = 8.4 Hz, 1H, Ar-H), 6.83 (dd, J = 8.6 Hz, 4H, Ar-H), 5.10
(s, 4H, Ar-CH2), 3.92 (m, 4H, O-CH2), 1.76, 1.45 (m, 8H, -CH2), 1.26 (m, 32H, -CH2),
0.87 (m, 6H, -CH3). 13C NMR (CDCl3), δ, ppm: 159.2, 152.9, 148.8, 129.0, 124.7, 126.7,
119.2, 117.8, 114.6, 114.2, 104.0, 71.3, 70.8, 68.0, 31.9, 29.7 29.6, 29.4, 29.3, 29.2, 26.0,
22.3, 14.1.
11,11'-(4-(2H-tetrazol-5-yl)-1,2-phenylene)bis(oxy)diundecan-1-ol (8e). The compound
was purified by column chromatography using dichloromethane as eluent and a light
o
brown solid was obtained. Yield 73%. Mp: 108-110 C. IR (KBr pellet) νmaxcm-1: 3452,
1
3073, 2921, 2849, 2745-2485, 1741,1607. H NMR (400 MHz, CDCl3), δ, ppm: 7.67 (sl,
2H, Ar-H), 6.9 (d, J = 8.0 Hz, 1H, Ar-H), 4.05 (s, 8H, O-CH2), 2.07 (s, 6H, -COOCH3),
1.81, 1.61, 1,43 (m, 12H, -CH2), 1.27 (m, 24H, -CH2). 13C NMR (CDCl3), δ, ppm: 171.8,
171.7, 151.7, 149.4, 126.2, 120.5, 115.9, 113.2, 112.1, 69.0, 64.8, 33.0, 32.7, 24.4, 29.3,
29.1, 29.0, 28.8, 28.5, 28.4, 28.1, 25.8, 25.7, 21.0, 20.9.
General procedure for the synthesis of target compounds 10a-d.
1,3,5-Tris-(5-(3,4-dodecyloxyphenyl)-1,3,4-oxadiazole-2-yl)benzene
(10a).
1,3,5-
benzenetricarboxylic acid (0.26 g, 1.2 mmol) in 6 ml of thionyl chloride was heated under
reflux for 4 h. The excess of thionyl chloride was removed by vacuum distillation and 20
mL of pyridine and 5-(2,4-acetoxyphenyl)tetrazole (2.0 g, 4 mmol) was added. The
mixture was heated under reflux for more 24 h. After cooling, the solution was poured into
ice/water (250 mL) and the precipitate was filtered off and washed with water. The

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purification was by column chromatography with dichloromethane/ethyl acetate (95:5) as
the eluent, resulting in 1.7 g of compound 10a. Yield 87%. IR (KBr pellet) νmaxcm-1: 3447,
1
2922, 2851, 1606, 1499. H NMR (400 MHz, CDCl3), δ, ppm: 9.03 (s, 3H, Ar-H), 7.78
(dd, J = 2.2, 8.5 Hz, 3H, Ar-H), 7.71 (d, J = 2.2 Hz, 3H, Ar-H), 7.02 (d, J = 8.5 Hz, 3H,
Ar-H), 4.15 (t, J = 6.4 Hz, 6H, O-CH2), 4.11 (t, J = 6.4 Hz, 12H, O-CH2), 1.88 (m, 12H, -
CH2), 1.52 (m, 12H, -CH2), 1.27 (m, 96H, -CH2), 0.89, 0.88 (t, J = 7.2, 7.0 Hz, 18H, -
CH3). 13C NMR (CDCl3), δ, ppm: 166.0, 162.8, 153.0, 149.7, 127.3, 126.6, 121.2, 115.8,
113.1, 111.8, 69.8, 69.4, 32.2, 30.0, 29.7, 29.5, 29.4, 26.3, 23.0, 14.4. Elemental analysis
(Carlo Erba model E-1110): Calcd. for C102H162N6O9:C 75.79, H 10.10, N 5.20 . Found: C
75.17, H 10.02, N 5.16. Calcd: m/z 1616.240 (M + H)+. Found: MALDI/MS: m/z
1616.525 [(M + H)+, 100%].
1,3,5-Tris(5-(3,4-bis(octan-3-yloxy)phenyl)-1,3,4-oxadiazol-2-yl)benzene (10b). Yield
1
40%. IR (KBr pellet) νmaxcm-1: 3439, 2958, 2875, 1602, 1497; H NMR (400 MHz,
CDCl3), δ, ppm: 9.05 (s, 3H, Ar-H), 7.77 (dd, J = 2.1, 8.4 Hz, 3H, Ar-H), 7.70 (d, J = 2.1
Hz, 3H, Ar-H), 7.03 (d, J = 8.4 Hz, 3H, Ar-H), 4.02, 3.97 (d, 12H, O-CH2), 1.83 (m, 6H, -
CH2), 1.54 (m, 12H, -CH2), 1.36 (m, 36H, -CH2), 0.99, 0.98, 0.93 (m, 36H, -CH3).13C
NMR (CDCl3), δ, ppm: 166.1, 162.8, 153.3, 150.3, 150.1, 127.3, 126.6, 121.0, 115.6,
112.8, 111.4, 71,9, 71.7, 39.9, 39.7, 30.9, 29.4, 29.4, 29.2, 24.2, 23.4, 14.4, 11.6, 11.5.
Elemental analysis (Carlo Erba model E-1110): Calcd. for C78H114N6O9:C 73.20, H, 8.98,
N 6.57 . Found: C 73.66, H 9.27, N 6.77. Calcd: m/z 1279.865 (M + H)+. Found:
MALDI/MS: m/z 1280.083 [(M + H)+, 100%].
1,3,5-Tris(5-(3,4-bis((S)-3-methyloctyloxy)phenyl)-1,3,4-oxadiazol-2-yl)benzene (10c).
1
Yield 39%. IR (KBr pellet) νmaxcm-1: 3447, 2963, 2871, 1607. H NMR (400 MHz,
CDCl3), δ, ppm: 9.03 (s, 3H, Ar-H), 7.78 (dd, J = 2.0, 8.4 Hz, 3H, Ar-H), 7.71 (d, J = 2.0
Hz, 3H, Ar-H), 7.03 (d, J = 8.4 Hz, 3H, Ar-H), 5.15(t, 6H, =CH), 4.17, (m, 12H, -OCH2),
2.05 (m, 12H, -CH2), 1.70 (s, 18H, -CH3), 1.62 (s, 18H, -CH3), 1.44 (m, 15H, -CH2), 1.26
(m, 15H, -CH2), 1.02 (m, 18H, -CH3). 13C NMR (CDCl3), δ, ppm: 166.0, 162.8, 153.0,
149.7, 131.6, 131.5, 127.3, 126.6, 125.0, 124.9, 121.2, 115.9, 113.0, 111.8, 68.1, 67.8,
37.6, 37.5, 36.4, 36.2, 30.0, 26.0, 25.8, 20.0, 18.0 . Elemental analysis (Carlo Erba model
E-1110): Calcd. for C84H126N6O9:C 73.97, H, 9.31, N, 6.16. Found: C 73.90, H 9.83, N
6.04. Calcd: m/z 1435.959 (M + H)+. Found: MALDI/MS: m/z 1436.207 [(M + H)+,
100%].

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5,5'-(5-(5-(3-(3-(Dodecyloxy)benzyloxy)-4-(4-(dodecyloxy)benzyloxy)phenyl)-1,3,4-
oxadiazol-2-yl)-1,3-phenylene)bis(2-(3,4-bis(4-(dodecyloxy)benzyloxy)phenyl)-1,3,4-
1
oxadiazole) (10d). Yield 53%. IR (KBr pellet) νmaxcm-1. H NMR (400 MHz, CDCl3), δ,
ppm: 8.89 (s, 3H, Ar-H), 7.75 (d, J = 8.4 Hz, 3H, Ar-H), 7.42, 7.36 (d, J = 8.2, 8.2 Hz,
12H, Ar-H), 7.07 (d, J = 8.4 Hz, 3H, Ar-H), 6.92, 6.90 (d, J = 8.2, 8.2 Hz, 12H, Ar-H),
5.20, 5.10 (s, 12H, Ar-CH2), 3.95 (m, 12H, O-CH2), 1.76 (m, 12H, -CH2), 1.40 (m, 12H, -
CH), 1.25 (s, 96H, -CH2), 0.87 (mt, 18H, -CH3) .13C NMR (CDCl3), δ, ppm: 165.4, 162.4,
159.1, 152.5, 149.3, 129.2, 129.0, 128.4, 128.2, 126.8, 126.5, 121.5, 116.1, 114.6, 113.1,
71.3, 70.1, 68.0, 31.9, 29.7, 29.6, 29.4, 26.1, 22.7, 14.1. Elemental analysis (Carlo Erba
model E-1110): Calcd. for C144H198N6O15: C 76.76, H 8.86, N 3.73. Found: C 76.38, H
8.98, N 3.82. Calcd: m/z 2253.5021 (M + H)+. Found: Q-TOF/MS m/z: 2253.5090 [(M +
H)+, 100%].
1,3,5-Tris-(5-(3,4-bis(undecyloxy-1-ol)-1,3,4-oxadiazole-2-yl)benzene (10f).
1,3,5-
benzenetricarboxylic acid (0.19 g, 0.9 mmol) in 5 ml of thionyl chloride was heated under
reflux for 4 h. The excess of thionyl chloride was removed by vacuum distillation and 20
mL of pyridine and compound 8e (1.7 g, 2.8 mmol) was added. The mixture was heated
under reflux for more 24 h. After cooling the room temperature, the solution was poured in
ice/water (250 ml) and the precipitate was filtered off and washed with water, obtaining the
compound 10f with acetyl group, it wasn’t isolated. Then, immediately the compound 10f
was hydrolyzed using 0.34 g (0.9 mmol) of NaOH in 30 mL of THF, after heating under
reflux for 12h. The solution was cooled to room temperature, acidified to pH 4 with HCl
aqueous solution (15%) and poured in 200 mL of ice/water, and then the precipitate was
filtrated. The purification was by column chromatography with dichloromethane/ethyl
acetate (95:10) as the eluent, resulting 0.6 g of compound 10f, with free hydroxyl group at
o
the end of the alkyl chain. Yield 45%; Mp: 109-111 C IR (KBr pellet) νmaxcm-1: 3397,
2921, 2850, 1605; 1H NMR (400 MHz, CDCl3), δ, ppm: 9.03 (s, 3H, Ar-H), 7.77 (dd, J =
2.0, 8.6 Hz, 3H, Ar-H), 7.70 (d, J = 2.0 Hz, 3H, Ar-H), 7.02 (d, J = 8.6 Hz, 3H, Ar-H),
4.15, 4.11(t, J = 4.3, 4.3 Hz, 12H, -OCH2), 3.65 (m, 12H, HO-CH2-), 1.91 (m, 12H, -CH2),
1.59 (m, 12H, -CH2), 1.32 (s, 84H,-CH2).13C NMR (CDCl3), δ, ppm: 166.2, 153.2, 149.9,
127.5, 124.9, 121.4, 116.0, 113.3 112.1, 111.7, 70.0, 69.6, 63.5, 33.3, 32.4, 30.7, 30.2,
30.1, 30.0, 29.9, 29.7, 29.5, 26.5, 26.2, 23.2, 14.6. Elemental analysis (Carlo Erba model
E-1110): Calcd. for C96H150N6O15: C 70.81, H 9.29, N 5.16. Found: C 70.17, H 9.69, N

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5.02. MALDI/MS: Calcd: m/z 1650.106 (M + Na)+. Found: MALDI/MS: m/z 1650.525
[(M + Na)+, 100%].
1.0. NMR spectra of compounds 10a-d and 10f.
a)

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b)
Figure S1. 1H NMR (a) and 13C NMR (b) spectrum of compound 10a (CDCl3).
a)

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b)
Figure S2. 1H NMR (a) and 13C NMR(b) spectrum of compound 10b (CDCl3).
a)

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b)
Figure S3. 1H NMR (a) and 13C NMR (b) spectrum of compound 10c (CDCl3).
a)

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b)
Figure S4. 1H NMR (a) and 13C NMR (b) spectrum of compound 10d (CDCl3).

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a)
b)
Figure S5. 1H NMR (a) and 13C NMR (b) spectrum of compound 10f (CDCl3).
1.1. MS spectra

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(10a)
(10b)

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(10c)

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10d
10f
Figure S6. MALDI-MS spectra of compounds 10a-d and 10f.

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1.2. DSC Thermograms
(10a)
(10b)
(10c)
(10d)
Figure S7. DSC curves of the final compounds 10a-d, 10°C/min, first scans.

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1.3. X-Ray diffraction (XRD)
b)
33000
30000
27000
10d
d100 = 41.8
Å
300C
d100/d200 ~ 2.0
~ 4.5
Å
d200 = 21.5
Å
2000
1000
0
~ 3.4
Å
2
4
6
8
10 12 14 16 18 20 22 24 26 28 30
(deg.)
2θ
Figure S8. X-ray diffraction patterns of 1,3,4-oxadiazole 10a, 10b and 10d (a, b). Colh
mesophase: the reflections (100), (110), and (200) are due to the long-range intercolumnar
ordering.

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Table SI. X-ray diffraction data for the mesophases of the compounds 10a-d.
Compound Mesophase Temp. Parameters dobs(Å)
dcalc(Å)
31.1
18.0
15.6
24.3
(hkl)
100
110
200
100
a= 35.9 Å
31.1
17.9
16.1
24.3
Colh
Colh
Colh
150 oC
90 oC
30 oC
120 oC
30 oC
10a
10b
10c
h = 3,4 Å
a= 28.0 Å
h = 3,4 Å
a= 31.2 Å
12.4
27
12.2
27
200
100
h = 3,4 Å
a= 47.9 Å
13.8
41.5
13.5
41.5
200
100
Colh
Colh
10d
10d
h = 3,4 Å
a = 48.3Å
41.8
21.5
41.8
20.9
100
200
h = 3,4 Å

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1.4. TGA curves
TGA
DrTGA
mg/min
4.00
TGA
mg
DrTGA
mg
mg/min
6.00
3.00
Mid Point
Onset
429.15 C
407.84 C
453.62 C
2.00
0.00
-2.00
-4.00
5.00
4.00
3.00
2.00
1.00
Endset
0.00
Weight Loss
-1.916 mg
-61.195 %
2.00
1.00
Mid Point
Onset
424.58 C
416.19 C
440.24 C
Endset
426.27 C
436.20 C
Weight Loss
-3.660 mg
-65.427 %
-5.00
-0.00
-0.00
200.00
400.00
Temp [C]
600.00
800.00
-0.00
200.00
400.00
Temp [C]
600.00
(10a)
(10b)
TGA
mg
DrTGA
mg/min
TGA
mg
DrTGA
mg/min
7.00
6.00
5.00
4.00
3.00
2.00
Mid Point
432.42C
4.00
3.00
2.00
1.00
0.00
-1.00
2.00
0.00
-2.00
Onset
409.28C
461.98C
2.00
0.00
-2.00
-4.00
Endset
Weight Loss
-4.406mg
-62.284%
Mid Point
Onset
413.06C
368.31C
475.93C
444.62C
445.66 C
Endset
Weight Loss
-1.785mg
-55.974%
-0.00
200.00
400.00
Temp [C]
600.00
-0.00
200.00
400.00
Temp [C]
600.00
(10c)
(10d)
TGA
mg
DrTGA
mg/min
2.00
2.00
Mid Point
Onset
441.65C
417.93C
479.51C
Endset
Weight Loss
-1.359 mg
-67.478 %
0.00
1.00
437.46C
462.51C
-2.00
-0.00
-0.00
200.00
400.00
600.00
Temp [C]
(10f)

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Figure S9. TGA curves of the final compounds 10a-d and 10f.
Figure S10. Absorbance of compounds 10a-d and 10f in thin solid films at room
temperature.