Design, synthesis and fluorescence analysis of potential fluorescent markers based on cardanol and glycerol

Article abstract of DOI:10.1016/j.dyepig.2017.02.032

We report the synthesis and fluorescent properties of 1,4-disubstituted-1,2,3-triazoles (1a-c) based on pollutant wastes and by-products from the cashew and biodiesel industries as a design for fluorescent markers. The triazoles were synthesized in four steps; catalytic hydrogenation of cardanol, reaction with epichlorohydrin, azide substitution and/or epoxide opening and, Cu catalyzed click-chemistry of the azide with the ethynylanilines (6a-c). This procedure is a potential alternative to make fluorescent markers since it affords the intermediates in high yields, enabling one to produce the products in good quantities. Moreover, triazolazobenzenes (8a-c) were prepared by azo coupling of the trizoles (1a-c) with phenol to give a new option of dyes. Evaluation of the fluorescent properties of the achieved compounds showed that all triazole derivatives displayed good fluorescence emissions in the range of 325–400 nm, with a maximum of fluorescence intensity at around 350 nm when excited between 225 and 300 nm; besides, the para-triazolaniline exhibited a dual fluorescence emission, presenting an additional emission band in the blue range (400–500 nm).

Full text of DOI:10.1016/j.dyepig.2017.02.032

Accepted Manuscript
Design, synthesis and fluorescence analysis of potential fluorescent markers based
on cardanol and glycerol
Felipe C. Braga, Avvari N. Prasad, Roberto da Silva Gomes, Valter A. do
Nascimento, Samuel L. Oliveira, Anderson R.L. Caires, Dênis P. de Lima, Adilson
Beatriz
PII:
S0143-7208(16)31181-0
10.1016/j.dyepig.2017.02.032
DYPI 5810
DOI:
Reference:
To appear in: Dyes and Pigments
Received Date: 12 November 2016
Revised Date: 3 February 2017
Accepted Date: 16 February 2017
Please cite this article as: Braga FC, Prasad AN, da Silva Gomes R, do Nascimento VA, Oliveira SL,
Caires ARL, de Lima DP, Beatriz A, Design, synthesis and fluorescence analysis of potential fluorescent
markers based on cardanol and glycerol, Dyes and Pigments (2017), doi: 10.1016/j.dyepig.2017.02.032.
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ACCEPTED MANUSCRIPT
Design, synthesis and fluorescence analysis of potential fluorescent
markers based on cardanol and glycerol
Felipe C. Braga, Avvari N. Prasad, Roberto da Silva Gomes, Valter A. do Nascimento, Samuel L. Oliveira,
Anderson R. L. Caires, Dênis P. de Lima, and Adilson Beatriz
We provide an alternative to use cardanol and glycerol as building blocks to produce six structurally,
amphiphilic molecules. The meta-triazolaniline (1b) presented a high fluorescent signal at low
concentration (4 ppm), revealing to be the best candidate for a fuel marker.

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Design, synthesis and fluorescence analysis of potential fluorescent markers
based on cardanol and glycerol
Felipe C. Braga,a† Avvari N. Prasad,a† Roberto da Silva Gomes,b Valter A. do Nascimento,c Samuel
L. Oliveira,d Anderson R. L. Caires,*d Dênis P. de Limaa, and Adilson Beatriz*a
aInstituto de Química, Universidade Federal de Mato Grosso do Sul. Av. Senador Filinto Müller,
1555, CEP: 79074-460, Campo Grande, MS, Brazil
bFaculdade de Ciência Exatas e Tecnologia, Universidade Federal da Grande Dourados, Itahum, km
12 – Cidade Universitária, 79804-970, Dourados, MS, Brazil
cGrupo de Espectroscopia e Bioinformática Aplicados a Biodiversidade e a Saúde, Faculdade de
Medicina, CP 549, 79070-900 Campo Grande, MS, Brazil.
dGrupo de Óptica e Fotônica, Instituto de Física, Universidade Federal de Mato Grosso do Sul, CP
549, 79070-900 Campo Grande, MS, Brazil.
*Corresponding authors:
Adilson Beatriz, e-mail: adilson.beatriz@ufms.br
Anderson R. L. Caires, e-mail: anderson.caires@ufms.br
† These authors contribute equally to this work.
Abstract
We report the synthesis and fluorescent properties of 1,4-disubstituted-1,2,3-triazoles (1a-c) based
on pollutant wastes and by-products from the cashew and biodiesel industries as a design for
fluorescent markers. The triazoles were synthesized in four steps; catalytic hydrogenation of
cardanol, reaction with epichlorohydrin, azide substitution and/or epoxide opening and, Cu
catalyzed click-chemistry of the azide with the ethynylanilines (6a-c). This procedure is a potential
alternative to make fluorescent markers since it affords the intermediates in high yields, enabling
one to produce the products in good quantities. Moreover, triazolazobenzenes (8a-c) were prepared
by azo coupling of the trizoles (1a-c) with phenol to give a new option of dyes. Evaluation of the
fluorescent properties of the achieved compounds showed that all triazole derivatives displayed
good fluorescence emissions in the range of 325 to 400 nm, with a maximum of fluorescence
intensity at around 350 nm when excited between 225 and 300 nm; besides, the para-triazolaniline
exhibited a dual fluorescence emission, presenting an additional emission band in the blue range
(400-500 nm).

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Introduction
Organic compounds endowed with special photophysical properties, usually dyes, are
important for the development of many products such as photodynamic therapy
photosensitizers1, biomarkers2, components of solar cells3, chemical catalysts4, fuel industry
markers5 and other technological products6. Fuel fluorescent markers have been drawing the
attention of many scientists since they can be applied as “silent” markers because they are
invisible in ambient light, but can be easily detected by their fluorescence7, offering many
vantages in comparison with colored products. However, there are certainly unresolved
issues to achieve a perfect fluorescent marker,8 making the research in this field very
promising, especially if one selects the biomass as a source of raw material to prepare these
compounds.
The Cashew Nut Shell Liquid (CNSL) is one of the low cost, bio based, and naturally
occurring resources of non-isoprenoid phenolic lipids consisting mainly of cardanol.9 CNSL
is produced in the food industry during one of the steps to get the cashew almond, by solvent
extraction of the cashew nut. It consists of anacardic acid (46-65%), cardanol (10-22%),
cardol (15-31%), traces of 2-methyl-cardol and others (0-2%), with their percentage varying
depending on the extraction process (Figure 1).10-12 In the industry the nut is heated up to
300 °C, during this process the CNSL’s main component (anacardic acid) is converted to
cardanol through decarboxylation, increasing its percentage to 68-74%. CNSL represents
nearly 25% of the nut weight and its production worldwide is estimated to about 300,000
tons per year which leads it to be a powerful phenolic pollutant.13 On the other hand,
cardanol can be considered as a building block for chemical synthesis and it adds value to
the CNSL generated in the cashew productive chain.13-15 Some successful examples of
amphiphilic molecular hybrid systems prepared from cardanol, such as phthalocyanines16
and porphyrins,7,17,18 prompted the search for new applications such as herein described as a
main topic.
[Figure 1 near here]
Currently, another important industrial residue is glycerol. Its use in the synthesis of
higher value chemicals has been highlighted in the green chemistry area for the last few
years. The exponential growth of biodiesel production, in which glycerol is generated as by-
product raised an enormous concern about its environmental impact. In fact, the glycerol
disposal is a major issue in the mass production of biodiesel and it is desirable to find

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alternatives for the consumption of extra volume of crude glycerol.19 Thus, glycerol has
been used as a versatile primary chemical building block to produce a great variety of
commercially valuable compounds.20-24
Taking into account the characteristics of the compounds previously mentioned, we aim
to combine their properties into single compounds with unique potentials. Herein we report
the design and synthesis of fluorescent amphiphilic molecules to function as potential
fluorescent markers, bearing a fluorophore and a hydrophobic group. The fluorophore
consists in an aniline coupled with a 1,2,3-triazole to complete the chromophoric system that
guarantees a fluorescent emission (Figure 2). 1,4-disubstituted-1,2,3-triazoles are simply
prepared by ‘‘Click chemistry’’, and they have been motifs in medicinal chemistry, used as
molecular chemical sensors and important linkers of conjugated systems.25,26 Besides it is a
simple reaction that involves only non-toxic reactants and green conditions. In the
meantime, the hydrophobic group (cardanol moiety) is sufficiently nonpolar to make it
soluble in biodiesel, for example.
[Figure 2 near here]
The target compounds were prepared from glycerol and cardanol. The photophysical
properties were determined by UV-Vis absorption and steady-state fluorescence analysis.
13
Characterization of the compounds was carried out by NMR (1H and C), IR spectroscopy,
and high-resolution mass spectrometry.
Results and discussion
A retrosynthesis analysis for the fluorescent amphipathic compounds is displayed in
Scheme 1. The 1,4-disubstituted-1,2,3-triazoles 1a-c can be generated via “Click
chemistry”27 starting from azide
saturated cardanol ( ) and glycerol (
epichlorohydrin (
7
and the ethynylanilines 6a-c. The linkage between
) can be easily made through a glycerol derivative
2
3
4
), which is easily obtained from glycerol.28
[Scheme 1 near here]

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To start the synthetic route, cardanol was isolated from CNSL, which was provided from
a local industry. The CNSL was initially filtered to remove solid impurities, and then
distilled under vacuum. The liquid obtained through distillation is a mixture of cardanol with
different number of double bonds in the side chain, though the main compound present is
the monounsaturated side-chain phenol.
This mixture of cardanols was then hydrogenated with Pd/C 5%. The reaction is fast and
the catalyst can be filtered off and used again after proper treatment. The product is purified
by crystallization in cold solvent and affords white pure powder (
2
) in 94% yield.
and DMAP (4-
For the next step, cardanol ), epichlorohydrin (4)
(
2
dimethylaminopyridine) were heated under reflux to give a mixture of products 5a and 5b
(Scheme 2). This methodology was improved in comparison with a previous one that used
pyridine. It seems that the pyridine drove the reaction to an undesired path forming a side
product. The use of a hindered catalyst proved to be better, therefore DMAP was selected to
increase the yield from 40% to about 90% overall. Compounds 5a and 5b were achieved
with ~54% and ~36% yield, respectively, and were substrates for the following steps.
[Scheme 2 near here]
Although two different compounds are inevitably generated from this reaction, both
products can be used to generate the azide compound
7 in excellent yields. Thus, we carried
out two pathways as an atom economic procedure using compounds 5a and 5b to give the
desired product.
The generality of epoxide opening was tested using a range of solvents to afford
reasonable to excellent yields (Table 1). Poly(ethylene glycol) (PEG- 400) was found to be
the most appropriate solvent system to achieve compound
7 with high yield (Table 1, Entry
6). Recently, PEG has attracted interest as a solvent due to its distinctive properties
including inexpensive, easy degradability and, low-toxicity, thus, improving green
conditions.29-33 Although compound
7 can be distinguished from its precursors by NMR
analysis, 5b and present similar spectra but they differ in the IR spectra, which shows a
7
characteristic stretching band for the N3 group at 2098 cm-1.34
[Table 1 near here]
Subsequently, compound
7 was subjected to “click chemistry” through CuAAC
cycloaddition of azide and terminal alkynes to attain the corresponding triazoles.35,36 To

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determine the best catalytic system for this transformation, we optimized typical reaction
parameters such as various Cu catalysts, solvents and, temperature, as illustrated in Table 2.
Among all catalysts, metallic copper powder in presence of water:acetone (2:1) exhibited
great catalytic activity towards the desired triazole under mild conditions (Table 2, Entry 9).
Thus, triazoanilines 1a-c were obtained by treatment of compound
7 with alkynes 6a-c
(Scheme 3).
[Scheme 3 near here]
[Table 2 near here]
In spite of existing few fluorescent azobenzenes,37 some derivatives can show high
fluorescence quantum yields, mainly those that are able to make interaction between the
nitrogen atom and electron acceptors.38 Besides, azo dyes are very important choromophores
largely used in textile industry and for the preparation of many high-tech futuristic
materials3a,5a Herein, owing to the nature of the groups in the target molecules, we have
decided to add an addition step to the route and react the triazoles 1a-c into the
corresponding azobenzenes 8a-c, and study their photophysical properties. Therefore,
o
compounds 1a-c were submitted to azo coupling reaction with sodium nitrite at 0 C
followed by treatment with a phenoxide solution to give 8a
compounds are isomers. The conversion to the less thermodynamically stable
may be achieved upon UV irradiation.39
-
c
(Scheme 4). All three
E
Z
isomer
[Scheme 4 near here]
Photophysical Studies
UV-Vis spectra of triazolanilines (1a-c) are showed in Figure 3. The results showed that the
maximum absorption wavelength had correlation with the NH2 substituent position on benzene ring
(ortho, meta or para). An absorption centred at 206 nm (range a) was observed for all compounds.
In contrast, a well-defined maximum absorption at 230 nm (range b) was observed for compounds
1a-b and a small shoulder for compound 1c. In addition, an absorption shoulder at around 254 nm
(range c) was observed for compounds 1a-b while only compound 1c exhibited an intense
absorption band centred at 280 nm (range c). Moreover, all compounds presented a small
absorption band over 290-350 nm range (range d), centred at 308 nm for compounds 1b-c and red-
shifted to 320 nm for compound 1a. To identify the nature of these bands, we performed ground
state calculations using the Austin Model 1 (AM1) semi-empirical method in Hyperchem 7.5

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Software. The AM1 is a semi-empirical method able to perform quantum calculation of molecular
electronic structure in computational modelling.40 The structures were then geometrically optimized
using the Polak-Ribiere method. After geometric optimization, single-point calculations were
performed using ZINDO/S parameters with the configuration interaction (CI) method set to “Singly
Excited”. The ZINDO/S method has proven to be extremely accurate in calculating electronic
transitions energies and intensities of both absorption an emission.41,42 In accordance to the
experimental observations, the theoretical results showed that the electronic transitions were NH2
substituent position dependent. The absorption at around 205 nm (range a) was obtained for all
compounds while strong absorptions in the range b (210-250nm) were observed for compounds 1a
and 1b (Table 3). Finally, as observed in the experimental result, a maximum absorption band at
around 284nm was determined only for compound 1c. All electronic transitions in the UV-Vis
range, with its respective wavelength and oscillator strength, obtained by AM1 semi-empirical
method are showed in Table S1 (see Supplementary material). AM1 calculations also revealed that
the electrons located at around the benzene ring with NH2 as substituent as well as in the ring
containing the N atoms have played key role in the electronic transitions (see the electronic
densities for the HOMO and LUMO states in Fig. S1 - S3 (see Supplementary material). In fact, as
expected, the substituent NH2 behaved as a donor group while the triazole ring as an acceptor group.
Additionally, it is well established that the absorption bands at around 210 and 254 nm are
attributed to the benzene ring as well as the absorption at 235 and 285 nm are assigned to the aniline
molecule (a benzene ring containing a NH2 as substituent) due to the intramolecular charge transfer
(ICT) from de donor group (NH2) to the benzene ring as demonstrated by Kimura et al. by
analysing the vacuum UV absorption spectra of aniline and its derivatives.43,44 Finally, it is worth to
point out that absorption bands over 300 nm with significant oscillator strength were not detected
by the theoretical calculation, probably due to the fact that the AM1 calculation was performed
assuming the absence of solvent (in vacuum).
[Figure 3 near here]
[Table 3 near here]
The fluorescence results revealed that emission intensity was strongly dependent of substituent
position in which the compound 1b (meta-aniline) presented higher fluorescence intensity as shown
in Fig. 4. Despite the difference in the fluorescence intensity, the inset in Fig. 4 shows that all
compounds (1a-c) presented an emission band in the UV range (between 300 and 400 nm) induced
by the Locally Excited (LE) state. However, in addition to the emission from LE state, para-aniline

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1c presented an additional emission band in the blue range (between 400 and 500 nm) as a result of
an extra relaxation channel, perhaps originated from the emergence of a Twisted Intramolecular
Charge Transfer (TICT) state due to an intramolecular charge transfer accompanied by an internal
rotation within the fluorophore. It is well known that molecules containing aniline group can present
the observed dual fluorescence behaviour due to emission from the LE state and an extra emission
band corresponding to transition from the TICT state at higher wavelengths.44 The dual
fluorescence behaviour of 1c, with a blue emission band, can be also visualized in the excitation-
emission contour map presented in Fig. 5. These data show that 1a-c exhibited fluorescence in the
325 to 400 nm range, with a maximum at around 350 nm, when excited between 225 and 300 nm
while only 1c presented the blue emission (between 400 and 460 nm) when excited in the 225-300
nm range. The excitation-emission map is totally in accordance with the determined absorbance as
the maximum emission was observed for an excitation at 240 nm for 1a-b and 270 nm for 1c.
Finally, it is important to point out that the contour maps were built using different fluorescence
intensity scales for a better visualization of the emissions, consequently, the excitation and emission
maps also stress that 1b presented higher fluorescence intensity.
To investigate the difference observed in the intensities, the relative fluorescence quantum yields
(Фꢀ) were determined by analysing the fluorescence and absorption spectra of 1a-c. The analyses
were performed by following the steps presented in details in a recent paper published by our
group45 where the relative fluorescence quantum yield ratio can be determined by Eq. 1:
Фꢁꢂ ꢄꢁꢂ. ꢅꢆꢃ
=
Фꢁꢃ ꢄꢁꢃ. ꢅꢆꢂ
Eq. 1
Where ꢅꢆ is the absorption intensity (absorbance) at a wavelength (ꢇꢈ) and ꢄꢁ is the area under
the emission curve, calculated by ꢅ ꢊꢇ ꢇ ꢋꢌꢇ , produced by an excitation at ꢇ . As presented in
ꢉ
ꢁ
ꢈ, ꢁ,
ꢁ
ꢈ
Table 4, the results revealed that Фꢁ of compound 1b was 9.35 and 6.32 higher than Фꢁ of
compound 1a and 1c, respectively. The calculations were carried out considering the absorbance
value and excitation wavelength at 265 nm and the emission in the 310-510 range, using the values
obtained from excitation-emission spectra presented in Fig. 5.
[Figure 4 near here]
[Table 4 near here]
[Figure 5 near here]

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Furthermore, when compounds 1a-c were under UV light (254 nm) they all changed their colour
to green (see Supplementary material, Fig. S7); that is a good indication of their potential
application as markers, since a simple test such as using incident UV light is enough to identify
their presence.46
The optical features of 8a-c were also determined by measuring their absorbance and
fluorescence spectra. The UV-Vis analysis showed that the azocompounds 8a-c presented different
optical characteristics as a function of diazenylphenol moiety position (Fig. 6). The results indicated
that compounds 8a-b presented three absorption bands at around 210, 248, and 345 nm in the
absorption ranges a, b and c, respectively. However, compound 8b showed higher absorbance than
compounds 8a; for instance, it presented a maximum absorption value in the range c 18 times
higher than compound 8b. The electronic transitions responsible for these absorptions may be
related to the electrons located at around the diazophenol group since the 248 and 345 nm have
been assigned to the nitrophenol and azobenzene molecules.47,48 In contrast, the compound 8c
absorbed significantly at 210 nm (range a), showing only the benzene absorption feature as the
diazophenol bands (at 248 and 345 nm) were suppressed. Although a decrease of absorption, as
observed for 8c when compared with 8a-b, may be related to a possible difference in the rotational
restriction around N=N bond. Further investigations are necessary since no conclusive answer is
available from the obtained results. For the diazenylphenol compounds the AM1 semi-empirical
method calculations were also performed to obtain the electronic transitions and the electronic
densities for the HOMO and LUMO states. The main electronic transitions obtained theoretically
are showed in Table 5. As experimentally observed, the theoretical results also revealed that the
electronic transitions were diazophenol substituent position dependent. Furthermore, the electronic
density of the HOMO and LUMO states indicated that the electrons from diazophenol group are
involved in the main electronic transitions (see Supplementary material, Fig. S4 – S6).
[Table 5 near here]
[Figure 6 near here]
Differently from triazolanilines 1a-c, the fluorescence measurements revealed that 8a-c did not
exhibit fluorescence signal when diluted at 4 ppm. In fact, only 8a and 8c presented low emission
intensity in the UV range even at high concentration (at 100 ppm), with a maximum at around 350
nm under excitation between 225 and 300 nm (see Supplementary material, Fig. S8). These low
fluorescence quantum yields of azobenzenes 8a-c when compared with the correspondent
triazolanilines (1a-c) can be explained for the fact that 8a-c have an additional ring (phenol),

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permitting additional non-radiative relaxation due to the decrease of molecular rigidity.49 Besides, it
is known that azobenzenes experiment efficient isomerization under photoexcitation, leading to low
fluorescence emission.38
Simultaneous thermal analysis (TG/DSC) was used to study the thermal behavior of
o
o
compounds 1a-c. Endothermic peaks are observed at 83.2 °C, 89.2 C and 122.9 C
corresponding to melting points of compounds 1a 1b and 1c, respectively. Exothermic
peaks are observed at around 350 °C for all compounds, corresponding to its oxidations. The
,
o
o
o
thermal stabilities are 266 C for 1a, 293 C for 1b and 223 C for 1c (see supplementary
material, Figure S9).
Experimental Part
General remarks
All reactions were carried out in clean glassware with magnetic stirring with the
exception of the catalytic hydrogenation that was carried out in a Parr Hydrogenation
apparatus. Chromatographic purification was performed on silica gel (Merck 100-200 mesh)
and analytical thin layer chromatography (TLC) on silica gel 60-F254, which was detected by
1
13
fluorescence. H NMR (300 MHz) and C NMR (75 MHz) spectra were measured with a
Bruker Avance DPX-300 spectrometer with CDCl3 and DMSO-D6 as solvents and recorded
1
in ppm relative to internal tetramethylsilane standard. The H NMR spectra are reported as
follows: δ/ppm (multiplicity, coupling constant
abbreviated as follows: s = singlet, d = doublet, doublet of doublets (dd), t = triplet, m =
multiplet. Coupling constants ( ) are quoted in Hertz and recorded to the nearest 0.1 Hz.
J/Hz, number of protons). Multiplicity is
J
High-resolution mass spectroscopy (HRMS) was performed on a UFLC Shimadzu LC-
20AD apparatus, with and IES-Q-QTOF-microTOF III detector (Bruker Daltonics) in
chemical ionization positive ion mode (m/z 120-1200). The samples were prepared with 0.1
g/mL (methanol/ water 7:3) and injected 1 ꢀL, using elution gradient water (phase A) and
acetonitrile (phase B), both with acetic acid 1%, isocratic method 50% and the running time
of 3 minutes. The infrared spectra were recorded on a FT-IR spectrometer and reported as
wavenumbers (cm-1). The melting point of the compounds was determined using a Quimis®
0340S23 melting point apparatus.
UV-Vis absorption measurements were performed using an absorption spectrophotometer
(Cary 50), containing a pulsed xenon lamp, a 0.25 m Czerny–Turner monochromator and a
Si diode detector. The UV-Vis spectra were measured in the 200-800 nm range by analysing
diluted samples in dichloromethane (CH2Cl2) at 4 ppm. Fluorescence measurements were

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collected by a spectrofluorimeter (Cary Eclipse) using a pulsed xenon lamp (80 Hz), with
peak power equivalent to 75 kW, as excitation source and a photomultiplier tube (R928) as a
fluorescence detector. The excitation and emission wavelengths were selected by using two
Czerny–Turner monochromators. The emission-excitation counter maps were determined by
collecting the emission between 220 and 520 nm when exciting in the 220-420 nm range.
For all spectroscopic analysis, the samples were diluted in dichloromethane (CH2Cl2) and
the measurements were performed at room temperature using a quartz cuvette with four
polished faces and 1 cm optical path length. The fluorescence measurements were carried
out using the right-angle geometry (i.e. the fluorescence was collected at a 900 angle in
respect to the excitation light).
Simultaneous TG–DSC curves were obtained with a thermal analysis system, model STA
449 F3 Jupiter® and experimental data were obtained through Proteus® Software. It was
employed alumina crucibles with sample masses near to 5.0 mg on purge gas flow (air) of
50 mL min-1 and heating rate optimized for 20 ºC min-1.
Synthesis
Extraction procedure of cardanol mixture from CNSL. Vacuum distillation was used in this
extraction, where 53.25 g of CNSL was heated to about 300oC for 4 h, under reduced
pressure in a short Path apparatus to give a 39.41 g (74%) of a cardanol mixture rich in
monounsaturated cardanol.
1
Cardanol mixture. (74% yield). Yellow oil. Rf= 0.33 (Hexane/EtOAc, 9:1); H NMR
(300.13 MHz, CDCl3) δ 7.13 (t, 3J(H,H) = 7.5 Hz, 1H; Ar-H), 6.75 (d, 3J(H,H) = 7.7 Hz, 1H;
Ar-H), 6.66 (s, 1H; Ar-H), 6.63 (d, 1H; Ar-H), 5.35 (m, 2H; CH=CH), 2.78 (m, 1H;CH),
3
2.54 (t, J(H,H) = 7.7 Hz, 2H; Ar-CH2C), 2.02 (m, 3H; CH3), 1.58 (m, 2H; CH2), 1.30 (m,
13
14H;CH2), 0.88 (m, 3H; CH3); C NMR (75.48 MHz, CDCl3) δ 155.45 (ArC-OH), 144.94
(ArC), 130.03, 129.91 (2x =CH), 129.45, 120.94, 115.45, 112.63 (4x ArCH), 35.90, 31.36,
29.80, 29.30, 27.27, 22.74 (13xCH2), 14.18 (CH3).
Typical procedure for the preparation of compound 2. The catalytic hydrogenation was
carried out in a Parr Hydrogenation apparatus. Pd/C (250 mg) was added to a solution of
cardanol mixture (5 g) in ethyl acetate (30 mL) and submitted to 60 Psi of hydrogen gas.
After 5h, the solution was filtered, to separate the catalyst, then the solvent was evaporated
and the solid was recrystallized with cold hexane (0oC) to give 4.70 g of compound
2 (93%
yield).
o
3-Pentadecylphenol (2). (76% yield). White powder. Mp: 40-43 C. Rf= 0.33 (Hexane/EtOAc,

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9:1); 1H NMR (300.13 MHz, CDCl3) δ 7.12 (t, 3J(H,H) = 6.0 Hz, 1H; Ar-H), 6.73 (d, 3J(H,H) = 6.0
3
Hz, 1H; Ar-H), 6.66 (s, 1H; Ar-H), 6.63 (m, 1H; Ar-H), 2.53 (t, J(H,H) = 9.0 Hz, 2H; Ar-CH2),
1.57 (m, 2H; CH2), 1.24 (m, 24H; CH2), 0.87 (m, 3H; CH3); 13C NMR (75.48 MHz, CDCl3) δ
155.37 (ArC-OH), 144.97 (ArC), 129.35, 120.97, 115.31, 112.47 (4x ArC-H), 35.82, 31.91, 31.28,
29.68, 29.59, 29.32, 22.69 (14x CH2), 14.10 (CH3).
Synthesis and isolation of 5a and 5b. To a solution of compound 2 (2.0 g, 6.58 mmol) in
epichlorohydrin (8.5 mL, 0.82 mol), catalytic quantity of DMAP was added (36 mg, 0.29 mmol)
and the mixture was kept under reflux for 4h. Then, the solution was washed with water and dried
over anhydrous sodium sulfate. Filtration followed by evaporation of the solvent led to the mixture
of 5a and 5b that were separated by silica gel chromatography to give 54% and 36% yields,
respectively.
2-[(3-pentadecylphenoxy)methyl]oxirane (5a). (54% yield). White solid. Mp: 40-43 oC. Rf=
0.63 (Hexane/EtOAc, 9:1); 1H NMR (300.13 MHz, CDCl3) δ 7.16 (t, 3J(H,H) = 7.71 Hz,
1H; Ar-H), 6.77 (d, 3J(H,H) = 7.67 Hz, 1H; Ar-H), 6.73 (s, 1H; Ar-H), 6.71 (m, 1H; Ar-H),
4.17 (dd, 3J(H,H) = 11.04 Hz, 2J(H,H) = 3.29 Hz, 1H; O-CH2), 3.95 (dd, 3J(H,H) = 10.96
Hz, 2J(H,H) = 5.55 Hz, 1H; O-CH2), 3.34 (m, CH-O-), 2.88 (t, 3J(H,H) = 4.49 Hz, 1H;
epoxide-CH2), 2.74 (dd, 3J(H,H) = 4.90 Hz, 2J(H,H) = 2.63 Hz, 1H; epoxide-CH2), 2.55 (t,
3J(H,H) = 7.45 Hz, 2H; CH2), 1.55 (m, 2H; CH2), 1.23 (m, 24H; CH2), 0.86 (t,3J(H,H) =
6.39 Hz, 3H; CH3); 13C NMR (75.48 MHz, CDCl3) δ 158.54 (ArC-O), 144.67 (ArC-),
129.21, 121.44, 114.96, 111.47 (4x ArCH), 68.61 (ArO-CH2), 50.21 (CH-epoxide), 44.68
(epoxide-CH2), 36.07, 32.04, 31.46, 29.80, 29.71, 29.63, 29.48, 29.43, 22.79 (14x CH2),
14.20 (CH3).
1-chloro-3-(3-pentadecylphenoxy)propano-2-ol (5b). (36% yield). White solid. Rf= 0.33
1
(Hexane/EtOAc, 9:1); H NMR (300.13 MHz, CDCl3) δ 7.18 (t, 3J(H,H) = 7.64 Hz, 1H; Ar-
H), 6.79 (d, 3J(H,H) = 6.79 Hz, 1H; Ar-H), 6.73 (s, 1H; Ar-H), 6.70 (m, 1H; Ar-H), 4.19 (m,
3
1H; HO-CH), 4.02 (m, 2H; O-CH2) 3.74 (m, 2H; CH2-Cl), 2.55 (t, J(H,H) = 7.75 Hz, 2H;
13
CH2), 1.58 (m, 2H; CH2), 1.24 (m, 24H, CH2), 0.86 (t,3J(H,H) = 6.39 Hz, 3H; CH3); C
NMR (75.48 MHz, CDCl3) δ 158.18 (ArC-O), 144.88 (ArC), 129.29, 121.65, 114.76,
111.45 (4x ArCH), 69.92 (CH-OH), 68.32 (O-CH2), 45.98 (CH2-Cl), 36.00, 31.93, 31.40,
29.68, 29.59, 29.51, 29.36, 29.35, 22.70 (14x CH2), 14.13 (CH3).
Synthesis of compound 7 pathway 5a to 7. Sodium azide (140 mg, 2.15 mmol) was added to a
solution of the epoxide 5a (520 mg, 1.44 mmol) in PEG 400 (4.40 mL). The solution was stirred at
60°C for 4 h and then diluted with ethyl acetate (10 mL). The solution was washed with brine (3x 5

ACCEPTED MANUSCRIPT
mL) and the organic layer was dried with anhydrous sodium sulfate. Filtration followed by
evaporation of the solvent led to the crude product that was purified by silica gel chromatography to
yield the correspondent azide 7 (506 mg, 1.25 mmol, 87%).
Synthesis of compound 7 pathway 5b to 7. A mixture of compound 5b (765 mg, 1.93 mmol) and
Sodium azide (250 mg, 3.85 mmol) and 3 mL of DMSO was stirred at 80°C for 6h. Then the
reaction mixture was poured into water (10 mL), extracted with hexane - diethyl ethyl (1:1) mixture
(2x 10 mL). The extracts were washed with brine (10 mL), dried over anhydrous sodium sulphate
and evaporated. The residue was dried under vacuum at room temperature to afford a colourless oil
(7). (757 mg, 1.87 mmol, 97%).
1-(3-pentadecylphenoxy)-3-(2-triaz-1-en-2-yn-1-yl)propan-2-ol (7). (87% yield). Yellow oil. Rf=
0.35 (Hexane/EtOAc, 9:1); IR (film) νmax 3409, 2923, 2854, 2102, 1593, 1446, 1269, 1099, 1053,
1
945, 875 cm-1; H NMR (300.13 MHz, CDCl3) δ 7.17 (t, 3J(H,H) = 7.67 Hz, 1H; Ar-H), 6.79 (d,
2J(H,H) = 7.38 Hz, 1H; Ar-H), 6.74 (s, 1H; Ar-H), 6.70 (m, 1H; Ar-H), 4.14 (m, 1H; CH-OH), 3.98
(d, 3J(H,H) = 5.04 Hz, 2H; O-CH2), 3.49 (m, 2H; CH2-N3), 2.57 (t, 3J(H,H) = 7.56 Hz, 1H; Ar-CH2),
1.60 (m, 2H; CH2), 1.27 (m, 24H; CH2), 0.89 (m, 3H; CH3); 13C NMR (75.48 MHz, CDCl3) δ
158.30 (ArC-O), 144.82 (ArC-), 129.26, 121.59, 114.80, 111.50 (4x ArC-H), 69.34 (CH-OH),
69.00 (O-CH2), 53.50 (CH2-N3), 36.03 (Ar-CH2), 31.96, 31.41, 29.72, 29.64, 29.55, 29.39, 22.71
(13x CH2), 14.13 (CH3).
General procedure for the preparation of 1a-c. Example for 1a: To a 10 mL round bottom flask,
2-ethynylaniline (137 mg, 1.17 mmol) and powdered copper metal (20 mg, 0.31 mmol) was added
to a solution of compound 7 (314 mg, 0.78 mmol) in 2.5 mL of water:acetone (2:1). The mixture
was stirred for 12h. After completion of the reaction, ethyl acetate was added to the solution,
washed with water and, the organic layer was dried and evaporated. The crude residue was purified
by silica gel chromatography to yield compound 1a (272 mg, 0.52mmol, 67%).
1-[4-(2-aminolphenyl)-1H-1,2,3-triazol-1-yl]-3-(3-pentadecylphenoxy)propan-2-ol (1a). (54%
o
1
yield). Brown solid. Mp: 80-85 C. Rf= 0.15 (hexane/EtOAc, 8:2); H NMR (300.13 MHz, CDCl3)
δ 8.43 (s, 1H; NCH=CNAr), 7.41 (d, 3J(H,H) = 7.38 Hz, 1H; Ar-H), 7.13 (t, 3J(H,H) = 7.89 Hz, 1H;
3
3
Ar-H), 6.98 (t, J(H,H) = 7.27 Hz, 1H; Ar-H), 6.72 (m, 4H; Ar-H), 6.54 (t, J(H,H) = 7.13 Hz, 1H;
3
2
Ar-H), 6.15 (s, 2H; NH2), 5.58 (d, J(H,H) = 5.19 Hz, 1H; Ar-H), 4.60 (dd, J(H,H) = 13.67 Hz,
2
3
3J(H,H) = 2.70 Hz, 1H; O-CH2), 4.43 (dd, J(H,H) = 13.30 Hz, J(H,H) = 7.52 Hz, 1H; O-CH2),
5.25 (m, 1H; CH-OH), 3.91 (m, 2H; CH2-N), 2.47 (m, 2H; Ar-CH2), 1.49 (m, 2H; CH2), 1.18 (m,
24H; CH2), 0.80 (m, 3H, CH3); 13C NMR (75.48 MHz, CDCl3) δ 158.83, 147.53, 146.06, 144.42 (
4x ArC), 129.62, 128.75, 127.95, 122.65, 121.23 (5x ArC-H), 116.38 (Ar-C=), 116.20, 115.05 (2x
ArC-H), 113.29 (CH=), 112.03 (ArC-H), 69.84 (O-CH2), 68.34 (HO-CH), 53.34 (CH2N), 35.69

ACCEPTED MANUSCRIPT
(Ar-CH2), 31.78, 31.36, 29.54, 29.21, 22.57 (13x CH2), 14.34 (CH3); HRMS (ESI) m/z calcd for
C32H49N4O2 512.3848, found 521.3850.
1-[4-(3-aminophenyl)-1H-1,2,3-triazol-1-yl]-3-(3-pentadecylphenoxy)propano-2-ol (1b). (39%
o
1
yield). Gray solid (green in solution). Mp: 90-95 C. Rf= 0.21 (hexane/EtOAc, 5.5:4.5); H NMR
3
(300.13 MHz, CDCl3) δ 7.7 (s, 1H; NCH=CNAr), 7.08 (t, J(H,H) = 7.67 Hz, 1H; Ar-H), 6.99 (m,
3
1H; Ar-H), 6.95 (m, 2H; Ar-H), 6.71 (d, J(H,H) = 7.23 Hz, 1H; Ar-H), 6.67 (s, 1H;Ar-H), 6.62 (d,
3
3J(H,H) = 8.04 Hz, 1H; Ar-H), 6.49 (d, J(H,H) = 6.94Hz, 1H; Ar-H), 4.55 (m, 1H; CH-OH), 4.37
(m, 2H; O-CH2), 3.91 (m, 2H; CH2-N) 2.48 (t, 3J(H,H) = 7.27 Hz, 2H, Ar-CH2) 1.52 (m, 2H, CH2),
13
1.21 (m, 24H, CH2), 0.83 (m, 3H CH3); C NMR (75.48 MHz, CDCl3) δ 158.23, 147.42, 146.86,
144.88, 131.05 (4x ArC and 1xAr-C=), 129.74, 129.31, 121.59, 115.97, 115.02, 114.82, 112.21,
111.41 (8x ArC-H and 1x CH=), 68.91 (O-CH2), 68.80 (HO-CH), 53.48 (CH2N), 36.03, 31.94,
31.45, 29.72, 29.65, 29.57, 29.42, 29.38, 22.71 ( 14xCH2), 14.15 (CH3); HRMS (ESI) m/z calcd for
C32H49N4O2 521.3848, found 521.3850.
1-[4-(4-aminophenyl)-1H-1,2,3-triazol-1-yl]-3-(3-pentadecylphenoxy)propano-2-ol (1c). (69%
o
1
yield). Yellow solid. Mp: 120-125 C. Rf= 0.30 (EtOAc/ Hexane; 5.5:4.5); H NMR (300.13 MHz,
CDCl3) δ 7.72 (s, 1H; NCH=CNAr), 7.54 (d, 3J(H,H) = 8.33 Hz, 2H; Ar-H aniline), 7.17 (t, 3J(H,H)
= 7.45 Hz, 1H; Ar-H cardanol), 6.79 (d, 3J(H,H) = 7.45 Hz, 1H; Ar-H cardanol), 6.69 (m, 4H; 2xAr-
H card and 2xAr-H aniline), 4.67 (d, 1H, CH-OH), 4.50 (m, 2H; O-CH2), 3.98 (m, 2H; CH2-N),
3
2.54 (t, J(H,H) = 7.52 Hz, 1H; Ar-CH2), 1.57 (m, 2H; CH2), 1.23 (m, 24H; CH2), 0.86 (m, 3H;
13
CH3); C NMR (75.48 MHz, CDCl3) δ 158. 07 (ArC-O), 148.05 (ArC-C ani), 146.51 (ArC-NH2),
144.94 (ArC-C card), 129.32 (CH card), 126.93 (2x CH ani), 121.75 (CH card), 120.86 (=C-N),
119.99 (HC= triazol), 115.22 ( 2x CH ani), 114.74 (CH card), 111.48 (CH card), 69.05 (CH-OH),
68.66 (O-CH2), 52.85 (CH2-N3), 35.99 (Ar-CH2), 31.91, 31.39, 29.67, 29.59, 29.51, 29.35, 22.68
(13x CH2), 14.10 (CH3); HRMS (ESI) m/z calcd for C32H49N4O2 521.3853, found 521.3850.
General procedure for the preparation of diazenyl compounds 8a-c. Example for 8b: Five
drops of HCl 6M at 0 oC were added to a solution of 1b (86 mg, 0.16 mmol) in methanol (5 mL). A
solution of sodium nitrite (57 mg, 0.83 mmol) in water (1.5 ml) at 0 oC was added and stirred for 30
o
min. The temperature was kept at 0-5 C throughout the reaction time. To the diazonium salt
solution formed was added a cold solution of phenol (23 mg, 0.24 mmol) in NaOH 7M (2.5 mL),
o
keeping the temperature around 0 C, when TLC monitoring indicated completion of the reaction
(8h). The solution was acidified with HCl 6M (until pH<9) and ethyl acetate was added (10 mL).
The organic layer was washed with brine (3 x 5 mL), dried over anhydrous sodium sulphate, filtered
and, the solvent evaporated under reduced pressure. The crude residue was purified by silica gel
chromatography to yield 8b (88 mg, 0.14 mmol, 86%).

ACCEPTED MANUSCRIPT
4-[(E)-(2-{1-[2-hydroxy-3-(3-pentadecylphenoxy)propyl]-1H-1,2,3-triazol-4-
1
yl}phenyl)diazenyl]phenol (8a). (10% yield). Orange oil. Rf= 0.31 (hexane/EtOAc, 7.5:2.5); H
NMR (300.13 MHz, CDCl3) δ 10.34 (s, 1H; OH-Ar), 8.44 (s, 1H; NCH=CNAr), 8.21 (d, 3J(H,H) =
7.89 Hz, 1H; Ar-H), 7.81 (d, 3J(H,H) = 8.77 Hz, 2H; Ar-H), 7.61 (d, 3J(H,H) = 8.19 Hz, 1H; Ar-H),
3
3
3
7.54 (t, J(H,H) = 6.80 Hz, 1H; Ar-H), 7.42 (t, J(H,H) = 7.60 Hz, 1H; Ar-H), 7.12 (t, J(H,H) =
3
7.16 Hz, 1H; Ar-H), 6.91 (d, J(H,H) = 8.84 Hz, 2H; Ar-H), 6,70 (m, 3H; Ar-H), 4.66 (dd, 2J(H,H)
3
3
2
= 14.03 Hz, J(H,H) = 2.78 Hz, 1H; OCH2), 4.51 (dd, J(H,H) = 6.87 Hz, J(H,H) = 14.25 Hz, 1H;
OCH2), 4.21 (m, 1H; CH-OH), 3.91 (m, 2H; CH2N), 2.46 (m, 25H; CH2), 1.47 (m, 2H; CH2), 1.15
(m, 25H; CH2), 0.78 (m, 3H; CH3); 13C NMR (75.48 MHz, CDCl3) δ 13C NMR (75.48 MHz,
CDCl3) δ 160.80, 158.27, 148.76, 144.75 (4x ArC), 130.27, 129.18, 128.33, 128.11, 127.20, 125.42
(2x), 121.45, 116.20 (2x), 115.74, 114.75, 111.58, 111.46 (2xArC, 1xAr-C=, 1xCH=, 10x ArC-H),
69.15 (O-CH2), 68.80 (CH-OH), 53.16 (CH2-N), 35.95 (Ar-CH2), 33.75, 31.85, 31.35, 29.96, 29.62,
29.46, 29.29, 27.01, 22.62 (CH2), 19.65 (CH3); HRMS (ESI) m/z calcd for C38H52N5O3 626.4063,
found 626.4065.
4-[(E)-(3-{1-[2-hydroxy-3-(3-pentadecylphenoxy)propyl]-1H-1,2,3-triazol-4-
yl}phenyl)diazenyl]phenol (8b). (86% yield). Orange solid. Mp: 60-70 oC. Rf= 0.22
1
(hexane/EtOAc, 7:3); H NMR (300.13 MHz, CDCl3) δ 10.29 (s, 1H; OH-Ar), 8.64 (s, 1H;
3
3
NCH=CNAr), 8.27 (s, 1H; Ar-H), 7.93 (d, J(H,H) = 7.60 Hz, 1H; Ar-H), 7.81 (d, J(H,H) = 8.70
Hz, 2H; Ar-H), 7.74 (d, 3J(H,H) = 7.79 Hz, 1H; Ar-H), 7.57 (t, 3J(H,H) = 7.75 Hz, 1H; Ar-H), 7.12
3
3
(t, J(H,H) = 7.82 Hz, 1H; Ar-H), 6.92 (d, J(H,H) = 8.77 Hz, 2H; Ar-H), 6.71 (m, 3H; ArH), 4.63
2
3
3
2
(dd, J(H,H) = 13.66 Hz, J(H,H) = 3.65 Hz, 1H; OCH2), 4.47 (dd, J(H,H) = 7.38 Hz, J(H,H) =
13.73 Hz, 1H; OCH2), 4.27 (m, 1H; CH-OH), 3.92 (m, 2H; CH2N), 2.46 (m, 2H; CH2), 1.47 (m,
2H; CH2), 1.15 (m, 25H; CH2), 0.78 (m, 3H; CH3); 13C NMR (75.48 MHz, CDCl3) δ 161.59,
158.80, 153.05, 145.95, 145.70, 144.40, 132.48 (6x ArC and 1x Ar-C=), 130.24, 129.58, 127.36,
125.34 (2x), 123.34, 122.11, 121.22, 118.73, 116.36 (2X), 114.98, 112.03 (12x ArC-H and 1x
CH=), 69.82 (O-CH2), 68.31 (CH-OH), 53.43 (CH2-N), 35.67 (Ar-CH2), 31.76, 31.33, 29.51, 29.35,
29.18, 22.55 (CH2), 14.30 (CH3); HRMS (ESI) m/z calcd for C38H52N5O3 626.4066, found
626.4065.
4-[(E)-(4-{1-[2-hydroxy-3-(3-pentadecylphenoxy)propyl]-1H-1,2,3-triazol-4-
yl}phenyl)diazenyl]phenol (8c). (62% yield). Orange solid. Mp: 140-145 oC. Rf= 0.30
1
(Hexane/EtOAc. 6.5:3.5); H NMR (300.13 MHz, CDCl3) δ 10.39 (s, 1H; OH-Ar), 8.67
3
3
(s,1H;CH=CNAr), 8.03 (d, J(H,H) = 8.50 Hz, 1H; Ar-H), 7.89 (d, J(H,H) = 8.50 Hz, 1H; Ar-H),
3
3
3
7.80 (d, J(H,H) = 8.85 Hz, 1H; Ar-H), 7.17 (t, J(H,H) = 7.50 Hz, 1H; Ar-H), 6.94 (d, J(H,H) =
2
3
8.85 Hz, 1H; Ar-H), 6.75 (m, 3H; Ar-H), 4.65 (dd, J(H,H) = 14.47 Hz, J(H,H) = 3.87 Hz, 1H;
3
2
OCH2), 4.49 (dd, J(H,H) = 7.71 Hz, J(H,H) = 13.99 Hz, 1H; OCH2), 4.27 (m, 1H, CH-OH), 3.95

ACCEPTED MANUSCRIPT
(m, 2H; CH2N), 2.50 (m, 2H, CH2), 1.22 (m, 2H; CH2), 1.20 (m, 25H, CH2), 0.83 (m, 3H, CH3); 13C
NMR (75.48 MHz, CDCl3) δ 161.03, 158.37, 151.40, 145.42, 145.37, 144.08, 132.80 (6x ArC and
1x Ar-C=), 129.29, 125.95 (2H), 124.90 (2H), 123.25, 122.90 (2H), 120.94, 116.03 (2H), 114.60,
111.69, (12x ArC-H and 1x CH=), 69.40 (O-CH2), 67.87 (CH-OH), 53.02 (CH2-N), 35.23 (Ar-
13
CH2), 33.72, 31.76, 31.34, 29.07, 28.75, 28.59, 28.48, 22.15 (CH2), 14.00 (CH3). C NMR (75.48
MHz, CDCl3) δ 160.80, 158.27, 148.76, 144.75 (4x ArC), 130.27, 129.18, 128.33, 128.11, 127.20,
125.42 (2x), 121.45, 116.20 (2x), 115.74, 114.75, 111.58, 111.46 (2xArC, 1xAr-C=, 1xCH=, 10x
ArC-H), 69.15 (O-CH2), 68.80 (CH-OH), 53.16 (CH2-N),35.95 (Ar-CH2), 33.75, 31.85, 31.35,
29.96, 29.62, 29.46, 29.29, 27.01, 22.62 (CH2), 19.65 (CH3); HRMS (ESI) m/z calcd for
C38H52N5O3 626.4049, found 626.4065.
Conclusions
We provide an alternative to use cardanol and glycerol as building blocks to produce six
amphiphilic molecules. The photophysical results have shown that the synthesized
triazolanilines 1a-c presented good fluorescent features, and are good starting points for
research using them as fluorescent markers either on non-polar medium or on targets that
require polar specificity. It is worth to point out that 1b presented a high fluorescent signal at
low concentration (4 ppm), and consequently, revealing to be the best candidate to be
applied as a marker. Moreover, the blue emission observed for 1c can be used in
applications where an emission in the visible region is desirable. Taking into account that
none of the triazoles display fluorescent bands in the region where biodiesel is intrinsic
fluorophores as well as fluorescent impurities usually do,50 compounds 1a-c ought to be
tested as fluorescent markers since they may be an interesting alternative to the conventional
ones. On the other hand, azobenzenes 8a-c have poor fluorescent properties, making them
not suitable for use as a fluorescent marker. Finally, all reactions herein reported were
carried out under mild conditions and the reagents employed were chosen to minimize the
use and generation of hazardous substances.
Acknowledgements
We thank to CNPq for financial support (Grant Numbers: 400119/2014-5 and
404688/2013-6), FUNDECT (PRONEM – Grant Number: 054/12), and Kardol Indústria
Química Ltda. Dr Avvari is grateful to Young Talent Fellowship under the Brazilian
Scientific Mobility Program "Ciências sem Fronteiras” (Process number: 304629/2014-6).
Felipe C. Braga thanks to CAPES for Master Degree scholarship.

ACCEPTED MANUSCRIPT
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Legendo of Tables
Table 1 Optimization studies for ring opening of epoxide with azide.a
Table 2 Optimization reaction conditions for 1,2,3-triazoles.a
Table 3 Main electronic transition determined by AM1 semi-empirical method (in vacuum). Details
can be accessed in Table S1 in the Supplementary materials.
Table 4 Fluorescence quantum yield obtained by calculating the absorption and fluorescence
intensities.
Table 5 Main electronic transition determined by AM1 semi-empirical method (in vacuum). For the
complete results see Table S2 in the Supplementary materials.

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Tables
Table 1
Entry
Solvent
DMF
Temp (0C)
Yield (%)
1
2
3
4
5
6
7
8
140
r.t.
r.t.
r.t.
r.t.
60
45
-
DMF
THF
20
15
57
87
-
MeOH
PEG 200
PEG 400
Solvent-free
CH3CN
r.t.
r.t.
18
aReaction conditions: Epoxide 5a (0.14 mmol), sodium azide (0.21 mmol) and PEG-400 (1.5 mL) stirred for about 4 h.
Table 2
Entry
Catalyst
Solvent
Temp (0C)
Yield (%)
1
CuCl
CH3CN
r.t.
r.t.
r.t.
r.t.
r.t.
140
80
-
2
CuBr
CH3CN
10
-
3
Cu(OAc)2
Cu(OAc)2
Cu (0) powder
Cu (0) powder
CuCl
H2O
4
MeOH
15
34
12
-
5
H2O/tBuOH (2:1)
DMF
6
7
THF
8
Cu(OAc)2
Cu (0) powder
-
EtOH
60
18
69
-
9
H2O/Acetone (2:1)
H2O/Acetone (2:1)
Solvent-free
H2O/Acetone (2:1)
r.t.
10
11
12
25-80
Cu (0) powder
CuSO4.5H2O/NaASc
r.t.
r.t
42
28
aReaction conditions: Compound
stirred for about 12 h.
7
(0.078 mmol), terminal alkyne 6c (0.11 mmol), catalyst (10 mg) and solvent (2 mL)
Table 3
1a
1b
1c
Absorption range
Oscillator trength
Oscillator strength
Oscillator strength
λ (nm)
204
λ (nm)
207
λ (nm)
0.36
1.11
0.31
0.33
0.20
-
0.59
0.66
205
0.45
a
216
220
-
-
0.24
-
226
224; 226
258
0.10; 0.14
225
284
b
c
259
0.57
0.20
-
-
-
278
274
-
-
-
0.35

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Table 4
Sample ratio
ΦF ratio
9.35
1b /1a
1b /1c
1c /1a
6.32
1.74
Table 5
8a
8b
8c
Absorption range
a
Wavenumber
(nm)
Oscillator strength
Wavenumber
(nm)
Oscillator strength
Wavenumber
Oscillator strength
(nm)
216
0.21
235
241
248
258
265
0.35
0.52
0.28
0.40
0.24
231
241
264
270
0.42
0.24
0.02
0.12
238
242
250
261
270
288
324
0.94
0.28
0.44
0.21
0.07
0.21
0.62
b
c
296
325
0.09
1.17
353
1.48

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Legends of Figures
Figure 1 Chemical structures of CNSL´s main components.
Figure 2 General structure of the target compounds.
Figure 3 Absorption spectra of 1a-c when diluted in CH2Cl2 at 4 ppm. The letters represent
the electronic bands obtained by AM1 semi-empirical method as presented in details in
Table 3.
Figure 4 Fluorescence spectra of 1a-c when excited at 265 nm and diluted in CH2Cl2 at 4 ppm.
Inset: Normalized Fluorescence spectra.
Figure 5 Excitation-Emission map of 1a-c when diluted in CH2Cl2 at 4 ppm.
Figure 6 Absorption spectra of 8a-c when diluted in CH2Cl2 at 4 ppm. The letters represent the
electronic bands obtained by AM1 semi-empirical method as presented in details in Table 5.
Figures
OH
OH
OH
CO2H
C15H31-n
C15H31-n
Cardanol
HO
C15H31-n
Cardol
Anacardic acid
n = 0
OH
H3C
n = 2
n = 4
HO
C15H31-n
n = 6
Methylcardol
Figure 1

ACCEPTED MANUSCRIPT
OR
R = H or alkyl
lipophilic group
O
N
conjugated system
fluorophore
N
N
Figure 2
0.4
0.3
0.2
0.1
c
a
b
d
1a
1b
1c
0.0
0.3
0.2
0.1
0.0
0.2
0.1
0.0
200
215
230
245
260
275
290
305
320
335
350
Wavelength (nm)
Figure 3
200
1.0
0.8
0.6
0.4
0.2
0.0
1a
1b
1c
175
150
125
100
75
310
360
410
460
510
Wavelength (nm)
50
25
0
310
335
360
385
410
435
460
485
510
Wavelength (nm)
Figure 4

ACCEPTED MANUSCRIPT
300
45.00
1a
40.00
30.00
20.00
10.00
0.000
285
270
255
240
225
325 340 355 370 385 400 415 430 445 460
300
450.0
400.0
350.0
300.0
250.0
200.0
150.0
100.0
50.00
0.000
1b
285
270
255
240
225
325 340 355 370 385 400 415 430 445 460
300
30.00
20.00
10.00
0.000
1c
285
270
255
240
225
325 340 355 370 385 400 415 430 445 460
Emission (nm)
Figure 5
0.25
0.20
0.15
0.10
0.05
0.00
8a;
8b;
8c
a
b
c
200 220 240 260 280 300 320 340 360 380 400
Wavelength (nm)
Figure 6

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Legends of schemes
Scheme 1 Retrosynthetic analysis to achieve potential fluorescent products.
Scheme 2 Reaction of cardanol with epichlorohydrin.
Scheme 3 Synthetic route for triazolanilines 8a-c
.
Scheme 4 Synthesis of azobenzenes 8a-c
.
Schemes
N
N
O
+
N3
O
14
N
7
OH
OH
H2N
6a-c
1a-c
H2N
O
14
5
O
+
OH
Cl
Technical CNSL
OH
OH OH
O
Saturated cardanol (2)
Epichlorohydrin (4)
Glycerol (3)
Scheme 1

ACCEPTED MANUSCRIPT
O
O
OH
14
O
N3
OH
5a
4, DMAP
88ºC, Reflux
N
a
OH
N
14
%
7
9
14
,
C
º
0
8
,
O
7
O
Cl
S
M
D
2
14
5b
Scheme 2
OH
OH
O
O
N3
ethynylanlines 6a-c
N
N
Cuo, water:acetone (2:1)
r.t., ~12 h
N
14
14
7
H2N
1a = 2-NH2 (54%)
1b = 3-NH2 (83%)
1c = 4-NH2 (96%)
Scheme 3
1. MeOH, HCl, NaNO2
0oC (30 min)
1a-c
O
OH
2. Phenol, NaOH, 0oC
N
N
N
8a = 2-diazenylphenol (10%)
8b = 3-diazenylphenol (86%)
8c = 4-diazenylphenol (62%)
N
N
OH
Scheme 4