Regioselective preparation of functional aryl ethers and esters by stepwise nucleophilic aromatic substitution reaction

Article abstract of DOI:10.1016/j.jfluchem.2014.03.005

Functional aryl ethers bearing mono- and di-substituted azo compounds, allyl functionalities, vinyl phenyl moieties, trifluoromethyl (CF₃) groups, etc. were prepared by nucleophilic substitution reaction of 2,3,4,5,6-pentafluorobenzonitrile (PFBN) in a stepwise manner at room temperature in dipolar aprotic solvents in a regioselective manner. Mono substituted aryl ether further underwent two more substitutions at ortho and ortho′ positions either with the same or different phenoxides. However, para substituted monoesters as well as para-ether-ortho-ester obtained by using carboxylates as (one of the) nucleophiles did not undergo any further displacement. The synthetic strategy described here is useful for making various functional materials such as lubricants, liquid crystals, curing agents, pigments and superhydrophobic materials.

Full text of DOI:10.1016/j.jfluchem.2014.03.005

Journal of Fluorine Chemistry 162 (2014) 17–25
Contents lists available at ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Regioselective preparation of functional aryl ethers and esters by
stepwise nucleophilic aromatic substitution reaction
*
**
Ranganathan Krishnan , Anbanandam Parthiban
Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island 627 833, Singapore
A R T I C L E I N F O
A B S T R A C T
Article history:
Functional aryl ethers bearing mono- and di-substituted azo compounds, allyl functionalities, vinyl
phenyl moieties, trifluoromethyl (–CF3) groups, etc. were prepared by nucleophilic substitution reaction
of 2,3,4,5,6-pentafluorobenzonitrile (PFBN) in a stepwise manner at room temperature in dipolar aprotic
solvents in a regioselective manner. Mono substituted aryl ether further underwent two more
substitutions at ortho and ortho0 positions either with the same or different phenoxides. However, para
substituted monoesters as well as para-ether-ortho-ester obtained by using carboxylates as (one of the)
nucleophiles did not undergo any further displacement. The synthetic strategy described here is useful
for making various functional materials such as lubricants, liquid crystals, curing agents, pigments and
superhydrophobic materials.
Received 13 January 2014
Received in revised form 5 March 2014
Accepted 8 March 2014
Available online 15 March 2014
Keywords:
Nucleophilic substitution
Phenols
Aryl ethers
ß 2014 Elsevier B.V. All rights reserved.
Aryl esters
Room temperature
1. Introduction
suitably positioned to activate the displacement of fluorine as
fluoride (Fꢀ). Indeed this ability to undergo nucleophilic substitu-
Organic compounds containing multiple fluorine atoms are
high performance materials and applied in many areas such as
hydrophobic materials [1], lubricants [2], thermally stable
materials [3], dielectric materials [4], liquid crystals [5], etc. Due
to the unique properties of fluorinated compounds, these are also
used widely as drugs in various therapeutic areas such as
antifungal agents [6], antibiotics [7], antimalarial compounds
[8], antidepressants [9], anti-inflammatory agents [10], anesthetics
[11], and in biomedical research as drug delivery systems [12].
Quite apart from these applications, fluorinated compounds are
also valuable intermediates for preparing a variety of materials
such as contrast agents for bio-imaging applications [13],
electronic applications [14] and high performance coatings [15].
In aromatic compounds containing fluorine atoms, these atoms
are either present on the aromatic ring substituting H atoms or
attached as a pendant group such as perfluoroalkyl (e.g., –CF3 or
higher homologues). These fluorinated aromatic compounds of the
first category readily undergo nucleophilic substitution reactions,
particularly if the compound contains multiple F atoms on the
aromatic ring or if it possesses electron withdrawing groups
tion has been made use of for making various high performance
engineering thermoplastics such as poly(arylene ether)s viz.,
poly(ether ether ketone)s, (PEEK), poly(ether sulfone)s, poly(ether
imide)s, etc. which are well known for excellent properties such as
high temperature stability, high glass transition temperature, anti-
flammable nature, solvent resistance, etc. [16]. Fluorinated
aromatic compounds are also often used as building blocks in
the preparation of macrocycles [17], glycosyl donors [18], and
fused ring systems [19].
2. Results and discussion
Perfluoro and difluoro organic compounds such as 2,3,4,5,6-
pentafluorobenzonitrile [20] (PFBN) and 2,6-difluorobenzonitrile
[21] (DFBN) are valuable starting materials, because of its ability to
undergo nucleophilic substitution under mild conditions yielding
various organic compounds and functional polymers with highly
polar cyano (–CN) pendant groups [20d,21b].
The para F atom of PFBN readily undergoes nucleophilic
substitution selectively even at room temperature or lower [20d].
This superior reactivity of para F atom as compared to those at
ortho, ortho0 positions enabled us to prepare linear poly(arylene
ether)s with multiple pendant groups [20d]. As reported here, this
reactivity difference has been exploited to prepare various
symmetrically and unsymmetrically trisubstituted arylene ether
and ester derivatives under mild reaction conditions. It is useful to
*
Corresponding author. Tel.: +65 6796 3931; fax: +65 6796 6184.
Corresponding author. Tel.: +65 6796 3910; fax: +65 6796 6184.
E-mail addresses: ranganathan_krishnan@ices.a-star.edu.sg,
**
krishnanssb@gmail.com (R. Krishnan), a_parthiban@ices.a-star.edu.sg
(A. Parthiban).
http://dx.doi.org/10.1016/j.jfluchem.2014.03.005
0022-1139/ß 2014 Elsevier B.V. All rights reserved.

18
R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
note here that carboxylates have rarely been used as nucleophiles
in nucleophilic aromatic substitution reactions. Previously we
employed carboxylates as nucleophiles in nucelophilic aliphatic
substitution reactions to make unsaturated poly(ether ester)s and
polyesters [22].
In the first step of nucleophilic substitution reaction, the para
fluorine atom was selectively displaced with one equivalent of
(substituted) phenol in presence of base at room temperature or
below, quantitatively. Subsequent reaction(s) with two more
equivalents of similar or dissimilar nucleophiles displaces F atoms
at ortho and ortho0 positions as well. Thus this methodology offers a
unique advantage of making symmetrical or differently trisubsti-
tuted benzonitriles in a facile manner.
In this study, we used four different phenols viz., phenol, 3-
(trifluoromethyl)phenol, 3,5-bis(trifluoromethyl)phenol and 3-
phenoxyphenol as nucleophile to displace the para-fluorine atom
of PFBN. The nucleophilic aromatic substitution reaction pro-
ceeded smoothly in dipolar aprotic solvents in presence of base
such as potassium carbonate at room temperature for 24 h. The
preparation of various 4-phenoxy-2,3,5,6-tetrafluorobenzonitrile
(PTFBN) is shown in Scheme 1.
The nuclear magnetic resonance spectrum of F nuclei, 19F NMR
spectra, of PTFBN clearly indicate that the complete disappearance
of signal corresponding to the para fluorine atom at ꢀ141.75 ppm.
Also, the 19F NMR spectroscopic analysis of 2b (Figs. 1 and S1)
showed signals at ꢀ62.96 ppm, ꢀ131.5 ppm, and ꢀ150.42 ppm
corresponding to –CF3 group, meta and ortho F atoms respectively
with the intensity ratio of 3:2:2, as expected. The facile mono
substitution yielded analytically pure compounds as established
by elemental analysis. The nature of compounds varied from solid
to viscous liquid depending on the type of phenol used for
nucleophilic substitution reaction. The mono substituted PTFBN
were obtained in high yields (85–92%) after purification.
The mono substituted PTFBNs possess two more displaceable F
atoms of equal reactivity at ortho, ortho0 positions. Thus,
trisubstituted arylene ethers were prepared by employing two
equivalents of same or different phenols in a one or two step
reaction at room temperature respectively.
The disubstituted phenoxy benzonitriles, TriFBNs were
obtained by reacting PTFBN with one equivalent of phenol such
as 3-(trifluoromethyl)phenol, and 3,5-bis(trifluoromethyl)phenol
as shown in Scheme 2. These reactions usually yielded some
impurities such as trisubstituted compounds because of the equal
reactivity of fluorine atoms at ortho, ortho0 positions. In spite of this
side reaction, disubstituted compounds were obtained in high to
very high yields depending on the reactivity of monohydroxy
Fig. 1. Stacked 19F NMR spectra of 2,3,4,5,6-pentaflourobenzo-nitrile (PFBN), 4-
phenoxy-3-(trifluoromethyl)-2,3,5,6-tetraflouro benzonitrile (2b) and 2-[3,5-
bis(trifluoromethyl)phenoxy]-3,5-difluoro-6-(4-nitrophenoxy)-4-[3-(trifluoromethyl)-
phenoxy]benzonitrile (4e).
phenol moiety. The formation of trisubstituted product occurred
even when the reaction was carried out at lower temperatures
(5–10 8C) and with lower base concentration (0.75 equivalents).
Surprisingly the reactions with 3,5-bis(trifluoromethyl)phenol
proceeded with high yields for both mono (Scheme 1, 2c) as well
as disubstitution (Scheme 2, 3d). Earlier we noticed that the PTFBN
CN
CN
F
F
F
Ar-OH
F
F
F
CN
CN
RT / K2CO3
DMF (solvent)
F
F
F
F
F
O-Ar'
F
F
Ar'-OH
F
F
O-Ar
RT / K2CO3
DMF (solvent)
1
F
2
CN
CN
F
CN
CN
O-Ar
2
O-Ar
3
F
F
F
F
F
F
F
F
F
F
CF3
CF3
CN
O
CN
CN
O
CN
O
F
F
F
F
F
F
O
F
O
F
F
F
O
F
F
F
O
O
O
O
O
CF3
F
F
F
F
O
F3C
CF3
2c (92%)
CF3
(86%)
O
CF3
3c
(82%)
F3C
3b
CF3
(95%)
F3C
CF3
(71%)
2a
CF3
(83%)
(85%)
2b
2d
(87%)
3d
3a
Scheme 1. Regioselective synthesis of 4-phenoxy(substituted)-2,3,5,6-
tetraflurobenzonitriles (PTFB).
Scheme 2. Regioselective synthesis of disubstituted trifluorobenzonitrile ethers.

R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
19
substituted with 3,5-bis(trifluoromethyl)phenoxy group yielded
the arylene ether copolymers with the highest molecular weight
among various substituted PTFBN [20d]. Thus the nucleophilic
substitution of mono substituted PTFBN was influenced by the
type of substituent present in the phenoxy moiety as well as the
nature of nucleophiles. The 19F NMR spectroscopic analysis of
compound 3c (Fig. S2) in Scheme 2, showed that the signal ratio of
3:1:1:1 (ꢀ62.98 ppm (3F, s), ꢀ131.26 to ꢀ131.35 ppm (1F, dd),
ꢀ140.49 to ꢀ140.52 ppm (1F, d), ꢀ150.18 to ꢀ150.23 ppm (1F, d))
as expected thereby indicating the cleanliness of the reaction as
well as the purity of product.
The versatility of the process can be noticed by the experiments
described in subsequent sections. The remaining F atom at ortho0
position of the diphenoxy substituted benzonitrile was displaced
by several functional nucleophiles such as 2-allyl (–CH2–CH55CH2)
phenol (Scheme 3, 4a), 4-diazo (–N55N–) phenol (Scheme 3, 4b), 4-
vinyl (–CH55CH2) phenol (Scheme 3, 4c) and 4-nitro (–NO2) phenol
(Scheme 3, 4d/4e). We believe that compounds similar to 4c with
four –CF3 pendant groups would be useful for making highly
fluorinated polymers and thus are capable of influencing the
surface properties. The fluorine content of this polymer is about
10 wt% lower than that of pentafluoro styrene. However, the
presence of pendant –CN group as well as the potential to form
donor–acceptor complexes could add self assembly characteristics
which may aid in the formation of super hydrophobic surfaces.
Besides the various functional phenols, it was also possible to use
benzoic acid as nucleophile to form ether esters (Scheme 3, 4f/4g).
The 19F NMR spectrum of compound 4d (Fig. S3) in Scheme 3,
exhibited signals at ꢀ62.97 (3F, s), ꢀ137.47 to ꢀ137.48 (1F, d),
ꢀ140.02 to ꢀ140.03 (1F, d) (signals corresponding to two meta
fluorine atoms with equal intensity ratios) thereby confirming the
formation of unsymmetrical trisubstituted product in a facile
manner even with poor nucleophiles such as p-nitrophenoxide.
The compound 4e (Scheme 3) exhibited peaks corresponding to
two meta-fluorine atoms as well as six fluorine atoms associated
with the two –CF3 groups [19F NMR (ppm): ꢀ63.08 (3F, s), ꢀ63.22
(6F, s), ꢀ137.33 (2F, s)] (Fig. 1). Thus it is clear from the foregoing
experimental results that it is convenient to form symmetrically as
well as unsymmetrically substituted compounds by regioselective
nucleophilic substitution involving PFBN even with poor nucleo-
philes.
As described above, due to the similarity in reactivity between F
atoms at ortho, ortho0 positions of PTFBN, obviously, it was possible
to form aryl ethers with symmetrical substitution at 2,6-position
(Scheme 4). The usefulness of this process can be noticed by the
ability to make compounds such as 5 g, (Fig. 2) which is
comparable to widely used crosslinkers such as 1,4-divinyl
benzene. Because of the relatively larger size as well as due to
the presence of multiple pendant groups (–CF3) it may be possible
to influence the size of void in such crosslinked structures and
thereby the porosity of resulting materials. Such porous com-
pounds have wide applications in gas separation and storage of
hydrogen gas [23]. It was also possible to extend this methodology
to prepare aryl ethers bearing photoactive diazo (–N55N–) moiety
(Fig. 2, 5e), and allyl (–CH2–CH55CH2) (Fig. 2, 5f), functionality.
Thus this is a facile approach for introducing highly reactive
functionalities under very mild conditions. In the same way, the
Scheme 3. Regioselective synthesis of trisubstituted difluorobenzonitrile ethers
and esters.
Scheme 4. Synthesis of symmetrically substituted benzonitriles.

20
R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
Fig. 2. Trisubstituted difluorobenzonitrile ethers containing various functional
groups.
Scheme
5.
The
preparation
of
para
substituted
monobenzoxy
tetrafluorobenzonitrile (6).
unsymmetrically trisubstituted compounds were prepared from
various monohydroxy phenols such as phenol, 3-(trifluoro-
methyl)phenol, 3,5-bis(trifluoromethyl)phenol, and 3-phenoxy-
phenol and their combinations are presented in Fig. 3.
O
O C
CN
CN
F
F
F
F
F
The unusual behavior of carboxyl substituted substrate for
subsequent nucleophilic substitution reaction was further ex-
plored deeply in order to understand the limitation of this process.
As briefly mentioned earlier, the nucleophilic substitution
proceeded in a facile manner even with conjugated and thus
weaker nucleophiles such as carboxylate anions (Scheme 5,
compound 6). However, the reaction did not proceed beyond
the mono substitution stage either with carboxylates or phen-
oxides even when the reactions were attempted at high
temperatures (120 8C). This may be due to the combination of
reasons like disrupted planarity as well as competing reactions.
Subsequently, we attempted to incorporate ester functionality into
PTFBN (Scheme 6, 7a–d). Once again, our attempts to displace both
F atoms at ortho, ortho0 positions of PTFBN with two equivalents of
2 C6H5 -COOH
F
F
O
7
O
2
RT - 80oC / K2CO3
DMF (solvent)
O
O C
O
O C
O
O
O C
CN
CN
O
CN
O C
CN
F
F
F
F
F
F
F
F
F
F
F
F
O
O
O
F3C
CF
7c(52%)3
O Ph
(46%)
CF
3
7d
7b
7a
(48%)
(20%)
F3C
CN
O
Scheme 6. Different monobenzoxy trifluorobenzonitriles synthesized from 4-
CN
O
CF3
CN
O
O
F
O
O
F
O
F
phenoxy-2,3,5,6-tetrafluorobenzonitrile.
O
F
O
F
Ph-O
CF3
F3C
CF3
F3C
O-Ph
F
carboxylate yielded only the mono carboxylate substituted
product even after heating the reaction mixture at 65 8C. Upon
increasing the reaction temperature to 120 8C only charred mass
was obtained. The above results indicate that formation of ester
linkage either at the stage of mono substitution or at later stages
completely suppress any further substitution reaction irrespective
of the nature of nucleophile. This is most likely the result of steric
effect. Unlike ether (–O–) formation with phenols, the ester (–
COO–) formation likely leads to a bulkier substituted product. This
increased bulkiness of carboxylates could twist electron with-
drawing –CN group out of plane thereby affecting its activating
ability for nucleophilic substitution. Due to this reason, the F atom
at the ortho0 position is no longer activated for nucleophilic attack
by the second carboxylate nucleophile.
5h (79%)
5i
5j (66%)
(21%)
CN
O
F3C
F3C
CF3
CN
O
CN
O
F
O
F
O
F
O
F
H3C
CF3
F
CH3
F
O
O
O
CF3
5k (60%)
CF3
CF3
5l
(87%)
5m (69%)
CN
CN
CN
O
O
F
O
O
F
O
F
O
F
Ph-O
H3C
CH3
O-Ph
F
F
O
O
O
Similar steric effect can be expected in the monocarboxylate
product such as 4-benzoxy-2,3,5,6-tetrafluorobenzonitrile
(Scheme 5, compound 6). Here, the effect could be cascade in
nature. Accordingly, the bulkiness of compound 6 could twist the
two F atoms at 3,5-position which could in turn twist the two F
atoms at 2,6-position thereby making the F atoms at ortho, ortho0
positions out of plane and thus rendering them unsuitable for
further nucleophilic attack.
We also studied the effect of nature of substituents of phenoxy
moiety with three different para substituents such as 4-phenoxy-
(Scheme 6, 7a), 4-phenoxy-3-(trifluoromethyl)- (Scheme 6, 7b), 4-
phenoxy-3,5-bis(trifluoromethyl)- (Scheme 6, 7c) and 4-(m-
phenoxyphenol) (Scheme 6, 7d) for further nucleophilic substitu-
tion with carboxylates. However, there was no influence of para
substituents to form ortho and ortho0 substituted esters. The
esterification reactions yields (Scheme 6, compounds 7a–d) were
invariably lower than that of etherification reactions yields
(Scheme 2, compounds 3a–d).
F3C
5p (70%)
CF3
5n (80%)
CF3
F3C
CF3
5o (67%)
CN
CN
CN
O
F
O
O
O
F
O
O
F
Ph-O
CF3
F3C
O-Ph
F
F
F
O
O
O
F3C
CF3
CF3
5r (48%)
O
(78%)
Ph
F3C
5s
5q (87%)
CN
F3C
CF3
CF3
O
F
O
F
CN
O
O
F
F3C
CF3
F3C
F
O
O
O
Ph
O
Ph
5t (89%)
5u (91%)
Fig. 3. Chemical structure of unsymmetrically trisubstituted benzonitrile ethers.

R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
21
chloroform-d or DMSO-d6 as a solvent at room temperature.
Melting point measurement were carried out with pure samples
using Buchi melting point apparatus B-450 at the heating rate of
20 8C/min. Thin layer chromatography (TLC) were performed on
0.2 mm silica gel coated plates purchased from Merck, Germany
and visualization of the spots was accomplished by UV light
(254 nm). Mass analyses were carried out using Agilent 1200 LC
with 6210 MSD TOF (LC-TOF) instrument in negative mode
electron spray ionization technique (ESI). The elemental analyses
of samples were carried out using Thermo Scientific Flash 2000
CHNS/O Analyzer.
4.2.1. Synthesis of 2,3,5,6-tetrafluoro-4-[3-(trifluoromethyl)
phenoxy]benzonitrile (2b)
In a 50 mL two-neck round bottom flask was charged with 25 mL
of dry DMF followed by PFBN (1.0 mL, 8.11 mmol) and 3-
(trifluoromethyl)phenol (0.986 mL, 8.11 mmol) under inert atmo-
sphere.Potassiumcarbonate(1.68 g, 12.16 mmol)wasaddedandthe
reaction mixture was stirred for 24 h at room temperature. After the
reaction mixture was neutralized with acidified water and extracted
with ether (yield: 95%). The compound was purified by column
chromatography using ethylacetate/hexane to yields a pale yellow
viscous liquid of 4-phenoxy-3-(trifluoromethyl)-2,3,5,6-tetrafluor-
obenzonitrile (yield: 86%).
Fig. 4. Stacked 19F NMR spectra of 4-phenoxy-2,3,5,6-tetra flourobenzonitrile (2a)
and 2-cyano-3,4,6-trifluoro-5-phenoxy phenyl benzoate (7a).
The remaining F atom at the ortho0 position of diphenoxy
substituted benzonitrile (Scheme 2, compounds 3a–d) could be
conveniently displaced by carboxylate yielding bisaryl ether esters
(Scheme 3, compounds 4f–g). The esterfication reactions proceeded
even at room temperature though the yields were moderate (45–
52%). Increasing the reaction temperature (ꢁ80 8C) did not influence
either the yield or further substitution. In general, barring mono
esterification involving nucleophilic substitution at the para
position, all other substitutions by carboxylate proceeded with
low yields. This may be again due to the difficulty of formation of
suitable transition states caused by the bulkiness which may have
been induced by the conjugated nature of carboxylate anion as
compared to phenoxide nucleophile (Fig. 4).
1H NMR (400 MHz, CDCl3,
(s, 1H, ortho-), and 7.47–7.54 (q, 2H, para- and ortho0-); 19F NMR
(376 MHz, DMSO-d6,
d ppm): 7.17–7.19 (d, 1H, meta-), 7.27
d
ppm): ꢀ62.96 (3F, –CF3), ꢀ131.5 (2F, meta-
), and ꢀ150.42 (2F, ortho-). Anal. calcd for C14H4F7NO: C, 50.17; H,
1.20; N, 4.18; Found: C, 50.60; H, 1.05; N, 4.30.
4.2.2. Synthesis of 3-[3,5-bis(trifluoromethyl)phenoxy]-6-cyano-
2,4,5-trifluorophenyl benzoate (7c)
In a 50 mL two-neck round bottom flask containing 25 mL of
dry DMF was charged with purified sample of 4-[3,5-bis(trifluor-
omethyl)phenoxy]-2,3,5,6-tetrafluorobenzonitrile (400 mg,
0.99 mmol) and two equivalents of benzoic acid (242 mg,
1.98 mmol) followed by potassium carbonate (411 mg, 2.97 mmol)
and the reaction was continued 24 h at room temperature. The
reaction mixture was neutralized with acidified water and
extracted with ethyl acetate yields 64%. The compound was
purified by column chromatography using ethyl acetate/hexane
mixture yields brownish color solid of 3-[3,5-bis(trifluoromethyl)-
phenoxy]-6-cyano-2,4,5-trifluorophenyl benzoate (yield: 52%).
3. Conclusion
In conclusion, we have reported novel semifluorinated aryl
ethers and esters prepared by step wise nucleophilic aromatic
substitution reaction. We exploited this methodology to prepare
several aryl ethers possessing reactive, polymerizable and photo-
active functionalities. We believe this methodology is highly useful
for making materials suitable for diverse variety of applications
such as lubricants, super hydrophobic coatings, liquid crystals, gas
separation membranes, hydrogen storage, curing agents, pig-
ments, photosensitive materials and many others.
1H NMR (400 MHz, DMSO-d6,
7.93–7.98 (4H, m); 19F NMR (376 MHz, DMSO-d6,
(6F, s), ꢀ137.18 to ꢀ137.26 (1F, m), ꢀ152.06 (1F, b), ꢀ165.44 (1F,
b). ESI-TOF MS for C22H8F9NO3: Calcd: 505.28; found: 400.01
(MꢀCO-C6H5).
d
ppm): 7.86 (2H, s), 7.90 (2H, s),
ppm): ꢀ61.60
d
4. Experimental
4.3. Spectroscopic data of new compounds
4.1. Materials
4.3.1. Compound 2a. 2,3,5,6-tetrafluoro-4-phenoxybenzonitrile
Yield: 85% as white solid; mp: 63.5–66.6 8C; 1H NMR (400 MHz,
Phenol, 4-vinylphenol(10 wt% inpropyleneglycol), and m-cresol
were received from Sigma–Aldrich, USA. Pentafluorobenzonitrile
(PFBN), 3-(trifluoromethyl)phenol, 3,5-bis(trifluoromethyl)phenol,
4-phenylazophenol, 3-phenoxyphenol and potassium carbonate
were received from Alfa Aesar, USA and used without further
purification. o-Allylphenol was purchased from Kanto Chemical Co.
Inc., Japan. N,N-Dimethylformamide (DMF) was purified by Glass
contour-6 solvent purification system. All other reagents were used
as received.
CDCl3,
m); 13C NMR (CDCl3, 100 MHz,
147.13, 148.05, 149.59, 156.61; 19F NMR (376 MHz, CDCl3,
d
ppm): 6.92–6.94 (2H, d), 7.11–7.15 (1H, m), 7.28–7.32 (2H,
): 107.45, 116.35, 125.15, 130.32,
ppm):
d
d
ꢀ133.16 to ꢀ132.26 (2F, m), ꢀ150.56 to ꢀ150.66 (2F, m). Anal.
calcd for C13H5F4NO: C, 58.44; H, 1.89; N, 5.24; found: C, 58.40; H,
1.81; N, 5.01. ESI-TOF MS for C13H5F4NO: Calcd: 267.03; found:
264.02 (Mꢀ3H).
4.3.2. Compound 2b. 2,3,5,6-tetrafluoro-4-[3-
(trifluoromethyl)phenoxy] benzonitrile
4.2. Characterization
Yield: 86% as colorless viscous liquid. 1H NMR (400 MHz, CDCl3,
NMR (1H, 13C, and 19F) spectra were recorded on Bruker
UltraShield Avance 400 MHz NMR instrument using deuterated
d
ppm): 7.18–7.2 (1H, d), 7.28 (1H, s), 7.48–7.54 (2H, m); 13C NMR
(CDCl3, 100 MHz,
d): 107.22, 109.81, 113.72, 119.55, 122.01,

22
R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
131.06, 140.35, 142.80, 147.16, 149.77, 156.47; 19F NMR
(376 MHz, CDCl3,
m), ꢀ150.20 to ꢀ150.31(2F, m). Anal. calcd for C14H4F7NO: C,
50.17; H, 1.20; N, 4.18; found: C, 50.60; H, 1.05; N, 4.30. ESI-TOF MS
for C14H4F7NO: Calcd: 335.02; found: 332.02 (Mꢀ3H).
to ꢀ147.40 (1F, d). Anal. calcd for C22H7F12NO2: C, 48.46; H, 1.29; N,
2.57; found: C, 48.62; H, 1.15; N, 2.66. ESI-TOF MS for
C22H7F12NO2: Calcd: 545.03; found: 542.03 (Mꢀ3H).
d
ppm): 62.96 (3F, s), ꢀ131.30 to ꢀ131.40 (2F,
4.3.9. Compound 4a. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2-[2-(prop-2-en-1-yl)phenoxy]-6-[3-
(trifluoromethyl)phenoxy]-benzonitrile
4.3.3. Compound 2c. 4-[3,5-bis(trifluoromethyl)phenoxy]-2,3,5,6-
tetraflourobenzonitrile
Yield: 45% as sticky solid; 1H NMR (400 MHz, CDCl3,
d ppm):
Yield: 92% as white solid; mp: 87.3–92.4 8C; 1H NMR (400 MHz,
3.50–3.52 (1H, d), 3.57–3.58 (1H, s), 5.04–5.12 (2H, m), 5.97–6.06
(1H, m), 6.66–6.68 (1H, m), 7.10–7.28 (6H, m), 7.39–7.51 (3H, m),
CDCl3,
): 106.82, 109.77, 116.89, 119.11, 121.32, 123.14, 124.10, 134.11–
134.41, 140.29, 156.59; 19F NMR (376 MHz, CDCl3,
ppm): 63.17
d
ppm): 7.43 (2H, s), 7.73 (1H, s); 13C NMR (CDCl3, 100 MHz,
d
7.67 (1H, s); 19F NMR (376 MHz, CDCl3,
d
ppm): ꢀ63.01 (3F, s),
ꢀ63.26 (6F, s), ꢀ139.04 (1F, s), ꢀ140.59 (1F, s). Anal. calcd for
C31H16F11NO3: C, 56.46; H, 2.45; N, 2.12; found: C, 56.63; H, 2.53;
d
(6F, s), ꢀ130.33 to ꢀ130.44 (2F, m), ꢀ149.82 to ꢀ149.92 (2F, m).
Anal. calcd for C15H3F10NO: C, 44.69; H, 0.75; N, 3.47; found: C,
44.59; H, 0.82; N, 3.47. ESI-TOF MS for C15H3F10NO: Calcd: 403.01;
found: 400.00 (Mꢀ3H).
N, 2.32. ESI-TOF MS for C31H16F11NO3: Calcd: 659.10; found:
704.09 (M+2Na-H).
4.3.10. Compound 4b. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2-[4-(2-phenyldiazen-1-yl)phenoxy]-6-[3-
(trifluoromethyl)phen-oxy]benzonitrile
4.3.4. Compound 2d. 2,3,5,6-tetrafluoro-4-(3-
phenoxyphenoxy)benzo-nitrile
Yield: 87% as viscous liquid. 1H NMR (400 MHz, CDCl3,
d
ppm):
Yield: 52% as yellow solid; mp: 130.1–132.7 8C; 1H NMR
6.69–6.71 (2H, b), 6.80–6.83 (1H, b), 7.04–7.06 (2H, d), 7.16–7.20
(1H, t), 7.28–7.32 (1H, m), 7.37–7.41 (2H, t); 13C NMR (CDCl3,
(400 MHz, CDCl3,
s), 7.41 (2H, s), 7.47–7.54 (5H, m), 7.69 (1H, s), 7.90–7.91 (2H, d),
7.96–7.99 (2H, d); 19F NMR (376 MHz, CDCl3,
s), ꢀ63.22 (6F, s),-138.34 (1F, s), ꢀ139.12 (1F, s). Anal. calcd for
C34H16F11N3O3: C, 56.44; H, 2.23; N, 5.81; found: C, 57.00; H, 2.77;
N, 5.97. ESI-TOF MS for C34H16F11N3O3: Calcd: 723.10; found:
768.09 (M+2Na-H).
d ppm): 7.13–7.16 (2H, d), 7.26 (1H, s), 7.28 (1H,
100 MHz,
d
): 107.06, 107.38, 110.41, 114.80, 119.71, 124.44,
d
ppm): ꢀ63.00 (3F,
130.22, 131.00, 156.34, 157.54, 159.23; 19F NMR (376 MHz, CDCl3,
d
ppm): ꢀ131.95 to ꢀ132.06 (2F, m), ꢀ150.44 to ꢀ150.54 (2F, m);
Anal. calcd for C19H9F4NO2: C, 63.52; H, 2.52; N, 3.90; found: C,
63.54; H, 2.65; N, 3.95. ESI-TOF MS for C19H9F4NO2: Calcd: 359.06;
found: 356.09 (Mꢀ3H).
4.3.11. Compound 4c. 2-(4-ethenylphenoxy)-3,5-difluoro-6-
phenoxy-4-[3-(triflouromethyl)phenoxy]benzonitrile
4.3.5. Compound 3a. 4-[3,5-bis(trifluoromethyl)phenoxy]-2,3,5-tri-
fluoro-6-phenoxybenzonitrile
Yield: 33% as white solid; mp: 112.4–115.1 8C; 1H NMR
Yield: 83% as white sticky solid; 1H NMR (400 MHz, CDCl3,
d
(400 MHz, CDCl3,
6.64–6.71 (1H, dd), 6.95–7.02 (4H, m), 7.15–7.18 (3H, m), 7.20 (1H,
s), 7.34–7.41 (4H, m), 7.43–7.51 (1H, t) 19F NMR (376 MHz, CDCl3,
d ppm): 5.21–5.24 (1H, d), 5.65–5.70 (1H, d),
ppm): 6.97–6.99 (2H, d), 7.16–7.2 (1H, t), 7.34–7.38 (2H, t), 7.41
(2H, s), 7.70 (1H, s); 19F NMR (376 MHz, CDCl3,
d
ppm): ꢀ62.30 (6F,
d
s), ꢀ130.34 to ꢀ130.42 (1F, dd), ꢀ139.93 to ꢀ139.96 (1F, d),
ꢀ150.12 to ꢀ150.18 (1F, d). Anal. calcd for C21H8F9NO2: C, 52.85; H,
1.69; N, 2.93; found: C, 52.23; H, 1.64; N, 3.02. ESI-TOF MS for
ppm): ꢀ62.94 (3F, s), ꢀ139.88 to ꢀ139.88 (1F, d), ꢀ140.06 to
ꢀ140.07 (1F, d). Anal. calcd for C28H16F5NO3: C, 66.02; H, 3.17; N,
2.75; found: C, 66.58; H, 3.30; N, 3.03. ESI-TOF MS for
C
21H8F9NO2: Calcd: 477.04; found: 474.03 (Mꢀ3H).
C28H16F5NO3: Calcd: 509.11; found: 554.10 (M+2Na-H).
4.3.6. Compound 3b. 4-[3,5-bis(trifluoromethyl)phenoxy]-2,3,5-tri-
fluoro-6-[3-(trifluoromethyl)phenoxy]benzonitrile
4.3.12. Compound 4d. 3,5-difluoro-2-(4-nitrophenoxy)-6-phenoxy-
4-[3-(triflouromethyl)phenoxy]benzonitrile
Yield:71%aswhitestickysolid;1HNMR(400 MHz,CDCl3,
d
ppm):
7.16–7.18(1H,d),7.23(1H,s),7.42(2H,s),7.47–7.51(2H,t),7.71(1H,
s); 19F NMR (376 MHz, CDCl3,
Yield: 72% as white sticky solid; 1H NMR (400 MHz, CDCl3,
d
ppm): 6.97–6.99 (3H, d), 7.14–7.18 (3H, m), 7.23 (1H, s), 7.33–7.37
(3H, t), 7.43–7.51 (3H, m); 19F NMR (376 MHz, CDCl3,
ppm):
d
ppm): ꢀ63.05 (3F, s), ꢀ63.23 (6F, s),
d
ꢀ129.42 to ꢀ129.50 (1F, dd), ꢀ139.99 to ꢀ140.02 (1F, d), ꢀ148.53 to
ꢀ148.58 (1F, d). Anal. calcd for C22H7F12NO2: C, 48.46; H, 1.29; N,
2.57; found: C, 48.94; H, 1.63; N, 2.68. ESI-TOF MS for C22H7F12NO2:
Calcd: 545.03; found: 542.02 (Mꢀ3H), 590.02 (M+2Na-H).
ꢀ62.97 (3F, s), ꢀ137.47 to ꢀ137.48 (1F, d), ꢀ140.02 to ꢀ140.03 (1F,
d); Anal. calcd for C26H13F5N2O5: C, 59.10; H, 2.48; N, 5.30; found:
C, 59.25; H, 2.20; N, 5.68. ESI-TOF MS for C26H13F5N2O5: Calcd:
528.38; found: 528.38.
4.3.7. Compound 3c. 2,3,5-trifluoro-6-phenoxy-4-[3-
4.3.13. Compound 4e. 2-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-6-(4-nitrophenoxy)-4-[3-
(trifluoromethyl)-phenoxy]benzonitrile
Yield: 82% as sticky solid; 1H NMR (400 MHz, CDCl3,
d
ppm):
6.96–6.98 (2H, d), 7.14–7.18 (2H, m), 7.22 (1H, s), 7.33–7.35 (2H, t),
7.42–7.44 (1H, d), 7.47–7.50 (1H, t); 19F NMR (376 MHz, CDCl3,
(trifluoromethyl)phenoxy]benzonitrile
Yield: 68% as white solid; mp: 110.5–114.9 8C; 1H NMR
d
(400 MHz, CDCl3,
7.46 (1H, d), 7.49–7.52 (1H, t), 8.26–8.29 (4H, dd); 19F NMR
(376 MHz, CDCl3,
d ppm): 7.10–7.13 (4H, dd), 7.22 (1H, s), 7.44–
ppm): 62.98 (3F, s), ꢀ131.26 to ꢀ131.35 (1F, dd), ꢀ140.49 to
ꢀ140.52 (1F, d), ꢀ150.18 to ꢀ150.23 (1F, d). Anal. calcd for
d
ppm): ꢀ63.08 (3F, s), ꢀ63.22 (6F, s), ꢀ137.33
C
20H9F6NO2: C, 58.69; H, 2.22; N, 3.42; found: C, 58.45; H, 2.55; N,
(2F, s). Anal. calcd for C28H11F11N2O5: C, 50.62; H, 1.67; N, 4.22;
found: C, 50.88; H, 1.97; N, 4.56. ESI-TOF MS for C28H11F11N2O5:
Calcd: 664.05; found: 709.05 (M+2Na-H).
3.59. ESI-TOF MS for C20H9F6NO2: Calcd: 409.05; found: 454.05
(M+2Na-H).
4.3.8. Compound 3d. 2-[3,5-bis(trifluoromethyl)phenoxy]-3,5,6-tri-
4.3.14. Compound 4f. 3-[3,5-bis(trifluoromethyl)phenoxy]-6-cyano-
fluoro-4-[3-(trifluoromethyl)phenoxy]benzonitrile
2,4-difluoro-5-[3-(trifluoromethyl)phenoxy]phenylbenzoate
Yield: 95% as sticky solid; 1H NMR (400 MHz, CDCl3,
d
ppm):
7.17–7.18 (1H, m), 7.27 (1H, s), 7.40–7.51 (4H, m), 7.71 (1H, s); 19
NMR (376 MHz, CDCl3,
ppm): ꢀ63.08 (3F, s), ꢀ63.25 (6F, s),
ꢀ129.39 to ꢀ129.48 (1F, dd), ꢀ139.94 to ꢀ139.97 (1F, d), ꢀ147.34
Yield: 44% as white sticky solid; 1H NMR (400 MHz, DMSO-d6,
d
F
ppm): 7.43–7.47 (5H, m), 7.55–7.57 (2H, t), 7.79 (3H, s), 7.81 (2H,
s); 19F NMR (376 MHz, DMSO-d6,
ppm): ꢀ61.50 (3F, s), ꢀ61.68
(6F, s), ꢀ152.00 (2F, s). Anal. calcd for C29H12F11NO4: C, 53.80; H,
d
d

R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
23
1.87; N, 2.16; found: C, 53.31; H, 2.20; N, 2.64. ESI-TOF MS for
29H12F11NO4: Calcd: 647.06; found: 542.02 (MꢀCO-C6H5).
m), 6.65–6.67 (2H, d), 7.11–7.13 (2H, m), 7.16–7.19 (2H, m), 7.26–
7.29 (2H, t), 7.37 (2H, s), 7.68 (1H, s); 19F NMR (376 MHz, CDCl3,
ppm): ꢀ63.22 (6F, s), ꢀ140.85 (2F, s). Anal. calcd for C33H21F8NO3:
C, 62.76; H, 3.35; N, 2.22; found: C, 62.46; H, 3.57; N, 2.53. ESI-TOF
MS for: C33H21F8NO3: Calcd: 631.14; found: 676.13 (M+2Na-H).
C
d
4.3.15. Compound 4g. 3-[3,5-bis(trifluoromethyl)phenoxy]-2-cyano-
4,6-difluoro-5-[3-(trifluoromethyl)phenoxy]phenylbenzoate
Yield: 52% as white sticky solid; 1H NMR (400 MHz, DMSO-d6,
d
ppm): 7.02–7.04 (1H, d), 7.13 (2H, s), 7.33–7.37 (7H, m), 7.59 (2H,
s); 19F NMR (376 MHz, DMSO-d6,
4.3.22. Compound 5g. 4-[3,5-bis(trifluoromethyl)phenoxy]-2,6-bis(4-
ethenyl-phenoxy)-3,5-difluorobenzonitrile
d
ppm): ꢀ61.47 (3F, s), ꢀ61.63
(6F, s), ꢀ152.17 (2F, s). Anal. calcd for C29H12F11NO4: C, 53.80; H,
Yield: 35% as white solid; mp: 131.2–135.6 8C; 1H NMR
1.87; N, 2.16; found: C, 53.21; H, 2.32; N, 2.81. ESI-TOF MS for
(400 MHz, CDCl3,
6.64–6.71 (2H, dd), 6.95–6.97 (4H, d), 7.38–7.41 (6H, m), 7.67 (1H,
s); 19F NMR (376 MHz, CDCl3,
d ppm): 5.22–5.25 (2H, d), 5.66–5.70 (2H, dd),
C29H12F11NO4: Calcd: 647.06; found: 542.02 (MꢀCO-C6H5).
d
ppm): ꢀ63.20 (6F, s), ꢀ139.75 (2F,
4.3.16. Compound 5a. 3,5-difluoro-2,4,6-triphenoxybenzonitrile
Yield: 92% as white solid; mp: 125.1–130.4 8C; 1H NMR
s). Anal. calcd for C31H17F8NO3: C, 61.70; H, 2.84; N, 2.32; found: C,
62.04; H, 3.39; N, 2.64. ESI-TOF MS for C31H17F8NO3: Calcd: 603.11;
found: 648.10 (M+2Na-H).
(400 MHz, CDCl3,
d
ppm): 6.95–7.00 (6H, t), 7.10–7.15 (3H, m),
ppm): 140.19 (2F,
7.31–7.36 (6H, m); 19F NMR (376 MHz, CDCl3,
d
s). Anal. calcd for C25H15F2NO3: C, 72.29; H, 3.64; N, 3.37. Found: C,
72.38; H, 3.59; N, 3.42. Anal. calcd for C25H15F2NO3: C, 72.29; H,
3.64; N, 3.37; found: C, 72.11; H, 3.93; N, 3.80. ESI-TOF MS for
4.3.23. Compound 5h. 3,5-difluoro-4-phenoxy-2,6-bis[3-(trifluoro
methyl)phenoxy]benzonitrile
Yield: 79% as white solid; mp: 114.9–119.0 8C; 1H NMR
C
25H15F2NO3: Calcd: 415.38; found: 415.39.
(400 MHz, CDCl3,
7.31–7.36 (2H, m), 7.41–7.43 (2H, d), 7.47–7.51 (2H, t); 19F NMR
(376 MHz, CDCl3,
calcd for C27H13F8NO3: C, 58.81; H, 2.38; N, 2.54; found: C, 59.40;
H, 2.72; N, 2.58. ESI-TOF MS for C27H13F8NO3: Calcd: 551.08;
found: 596.07 (M+2Na-H).
d ppm): 6.96–6.98 (2H, d), 7.13–7.22 (5H, m),
4.3.17. Compound 5b. 3,5-difluoro-2,4,6-tris[3-
(trifluoromethyl)phen-oxy]benzonitrile
d
ppm): ꢀ62.95 (6F, s), ꢀ138.64 (2F, s). Anal.
Yield: 78% as white solid; mp: 110.5–113.6 8C; 1H NMR
(400 MHz, CDCl3,
7.46–7.50 (3H, t); 13C NMR (CDCl3, 100 MHz,
d
ppm): 7.11–7.22 (6H, m), 7.39–7.44 (3H, m),
): 109.76–109.83,
d
113.09–113.28, 119.13, 119.36, 121.45–121.63, 122.08, 122.64,
124.79, 130.34, 132.70, 133.02, 145.03–145.06, 147.58–147.62,
4.3.24. Compound 5i. 2,6-bis[3,5-bis(trifluoromethyl)phenoxy]-3,5-
di-fluoro-4-phenoxybenzonitrile
156.55, 156.76, 159.23; 19F NMR (376 MHz, CDCl3,
d
ppm): ꢀ62.98
Yield: 21% as white solid; mp: 138.5–143.1 8C; 1H NMR
(6F, s), ꢀ63.05 (3F, s), ꢀ138.62 (2F, s). Anal. calcd for C28H12F11NO3:
C, 54.30; H, 1.95; N, 2.26; found: C, 54.52; H, 2.35; N, 2.21. ESI-TOF
MS for C28H12F11NO3: Calcd: 619.06; found: 664.07 (M+2Na-H).
(400 MHz, CDCl3,
7.34–7.38 (2H, t), 7.43 (4H, s), 7.70 (2H, s); 19F NMR (376 MHz,
CDCl3,
ppm): ꢀ63.21 (12F, s), ꢀ137.04 (2F, s). Anal. calcd for
29H11F14NO3: C, 50.67; H, 1.61; N, 2.04; found: C, 50.96; H, 1.73;
d ppm): 6.98–7.00 (2H, d), 7.16–7.20 (1H, t),
d
C
4.3.18. Compound 5c. 2,4,6-tris[3,5-bis(trifluoromethyl)phenoxy]-
3,5-diflourobenzonitrile
N, 2.03. ESI-TOF MS for C29H11F14NO3: Calcd: 687.05; found:
732.05 (M+2Na-H).
Yield: 81% as pale yellow solid; mp: 154.0–160.5 8C; 1H NMR
(400 MHz, CDCl3,
(376 MHz, CDCl3,
(2F, s). Anal. calcd for C31H9F20NO3: C, 45.22; H, 1.10; N, 1.70;
found: C, 45.55; H, 1.46; N, 1.62. ESI-TOF MS for C31H9F20NO3:
Calcd: 823.03; found: 868.02 (M+2Na-H).
d
ppm): 7.42 (3H, s), 7.45 (6H, s); 19F NMR
4.3.25. Compound 5j. 3,5-difluoro-4-phenoxy-2,6-bis(3-
d
ppm): ꢀ63.27 (12F, s), ꢀ63.35 (6F, s), ꢀ137.40
phenoxyphen-oxy)benzonitrile
Yield: 66% as colorless sticky solid; 1H NMR (400 MHz, CDCl3,
d
ppm): 6.60–6.67 (4H, m), 6.73–6.76 (2H, d), 6.93–6.95 (2H, d),
7.00–7.04 (4H, d), 7.21–7.15 (3H, t), 7.21–7.28 (3H, m), 7.32–7.37
(5H, m); 19F NMR (376 MHz, CDCl3,
calcd for C37H23F2NO5: C, 74.12; H, 3.87; N, 2.34; found: C, 73.82;
H, 4.05; N, 2.73. ESI-TOF MS for C37H23F2NO5: Calcd: 599.15;
found: 644.15 (M+2Na-H).
d
ppm): ꢀ139.85 (2F, s). Anal.
4.3.19. Compound 5d. 3,5-difluoro-2,4,6-tris(3-
phenoxyphenoxy)benzo-nitrile
Yield: 84% as colorless viscous liquid; 1H NMR (400 MHz, CDCl3,
d
ppm): 6.60–6.65 (6H, m), 6.72–6.76 (3H, m), 7.00–7.05 (6H, m),
7.12–7.16 (3H, m), 7.23–7.26 (3H, ss), 7.33–7.37 (6H, t); 19F NMR
(376 MHz, CDCl3,
ppm): ꢀ139.91 (2F, s). Anal. calcd for
43H27F2NO6: C, 74.67; H, 3.93; N, 2.03; found: C, 74.40; H,
4.3.26. Compound 5k. 3,5-difluoro-2,6-diphenoxy-4-[3-
(trifluoromethyl) phenoxy]benzonitrile
d
C
Yield: 60% as white solid; mp: 131.4–133.8 8C; 1H NMR
4.08; N, 2.04. ESI-TOF MS for C43H27F2NO6: Calcd: 691.18; found:
736.17 (M+2Na-H).
(400 MHz, CDCl3,
7.11 (1H, s), 7.25–7.32 (5H, m), 7.35–7.39 (1H, t); 13C NMR (CDCl3,
100 MHz, ): 101.60, 110.40–110.44, 111.19, 112.94–113.05,
d ppm): 6.91–6.93 (4H, d), 7.04–7.08 (3H, t),
d
4.3.20. Compound 5e. 3,5-difluoro-4-phenoxy-2,6-bis[4-(2-phenyl-
diazen-1-yl)phenoxy]benzonitrile
116.21, 119.35, 121.28–121.39, 124.60, 130.26, 130.95, 132.61,
132.94, 137.98–138.24, 142.83–142.99, 144.97–145, 147.52–
147.55, 156.81, 157.14, 159.23; 19F NMR (376 MHz, CDCl3,
d
Yield: 94% as yellow solid; mp: 169.8–175.3 8C; 1H NMR
(400 MHz, CDCl3,
7.10–7.16 (4H, m), 7.32–7.36 (2H, t), 7.44–7.52 (6H, m), 7.89–7.90
(4H, d), 7.95–7.97 (4H, d); 19F NMR (376 MHz, CDCl3,
ppm):
d
ppm): 6.84–6.90 (1H, d), 6.99–7.01 (2H, d),
ppm): ꢀ62.94 (3F, s), ꢀ140.00 (2F, s). Anal. calcd for C26H14F5NO3:
C, 64.60; H, 2.92; N, 2.90; found: C, 64.52; H, 2.83; N, 2.72. ESI-TOF
MS for C26H14F5NO3: Calcd: 483.09; found: 528.08 (M+2Na-H).
d
ꢀ139.12 (2F, s). Anal. calcd for C37H23F2N5O3: C, 71.26; H, 3.72; N,
11.23; found: C, 71.27; H, 3.68; N, 11.08. ESI-TOF MS for
4.3.27. Compound 5l. 2,6-bis[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-4-[3-(trifluoromethyl)phenoxy]benzonitrile
C37H23F2N5O3: Calcd: 623.18; found: 668.17 (M+2Na-H).
Yield: 87% as white solid; mp: 156.8–159.3 8C; 1H NMR
4.3.21. Compound 5f. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2,6-bis[2-(prop-2-en-1-yl)phenoxy]benzonitrile
Yield: 71% as white solid; mp: 80.6–85.3 8C; 1H NMR (400 MHz,
(400 MHz, CDCl3,
d
ppm): 7.34–7.38 (3H, t), 7.43–7.47 (1H, t),
): 113.59–
7.71 (2H, s), 7.75 (4H, s); 13C NMR (CDCl3, 100 MHz,
d
113.63, 117.83–117.86, 118.89–119.04, 120.55, 122.20, 122.45,
125.14, 132.32, 134.03, 134.37, 146.70, 149.26, 158.43; 19F NMR
CDCl3,
d ppm): 3.57–3.58 (4H, d), 5.09–5.11 (4H, t), 5.98–6.08 (2H,

24
R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
(376 MHz, CDCl3,
d
ppm): ꢀ63.38 (3F, s), ꢀ63.45 (12F, s), ꢀ141.33
CDCl3,
d
ppm): ꢀ63.16 (6F, s), ꢀ139.57(2F, s). Anal. calcd for
(2F, s). Anal. calcd for C30H10F17NO3: C, 47.70; H, 1.33; N, 1.85;
found: C, 47.69; H, 0.89; N, 1.85. ESI-TOF MS for C30H10F17NO3:
Calcd: 755.04; found: 800.03 (M+2Na-H).
C39H21F8NO5: C, 63.68; H, 2.88; N, 1.90; found: C, 63.17; H, 3.12;
N, 1.95. ESI-TOF MS for C39H21F8NO5: Calcd: 735.13; found:
780.13 (M+2Na-H).
4.3.28. Compound 5m. 3,5-difluoro-2,6-bis(3-methylphenoxy)-4-[3-
(tri-fluoromethyl)phenoxy]benzonitrile
4.3.34. Compound 5s. 3,5-difluoro-2,6-diphenoxy-4-(3-
phenoxyphenoxy) benzonitrile
Yield: 69% as white solid; mp: 107.0–110.2 8C; 1H NMR
Yield: 78% as white solid; mp: 116.4–120.5 8C; 1H NMR
(400 MHz, CDCl3,
(2H, s), 6.95–6.98 (2H, d), 7.15 7.45–7.49 (1H, d), 7.20–7.26 (4H,
m), 7.39–7.41 (1H, d); 13C NMR (CDCl3, 100 MHz,
): 21.66, 101.74,
110.51, 113.01, 116.91, 119.41, 121.29–121.31, 125.39, 129.90,
130.94, 142.82–143.07, 145.01, 147.52, 156.89, 157.18; 19F NMR
d
ppm): 2.35 (6H, s), 6.76–6.78 (2H, dd), 6.82
(400 MHz, CDCl3,
6.97–7.03 (6H, m), 7.13–7.17 (3H, m), 7.24–7.28 (1H, dd), 7.33–
7.38 (6H, m); 19F NMR (376 MHz, CDCl3,
Anal. calcd for C31H19F2NO4: C, 73.37; H, 3.77; N, 2.76; found: C,
73.42; H, 3.58; N, 2.80. ESI-TOF MS for C31H19F2NO4: Calcd: 507.13;
found: 552.13 (M+2Na-H).
d ppm): 6.64–6.68 (2H, m), 6.73–6.75 (1H, dd),
d
d
ppm): ꢀ140.23 (2F, s).
(376 MHz, CDCl3,
d
ppm): ꢀ62.96 (3F, s), ꢀ140.26 (2F, s). Anal.
calcd for C28H18F5NO3: C, 65.76; H, 3.55; N, 2.74; found: C, 65.38;
H, 3.76; N, 2.69. ESI-TOF MS for C28H18F5NO3: Calcd: 511.12;
found: 556.12 (M+2Na-H).
4.3.35. Compound 5t. 3,5-difluoro-4-(3-phenoxyphenoxy)-2,6-bis[3-
(trifluoromethyl)phenoxy]benzonitrile
Yield: 89% as white solid; mp: 107.9–110.2 8C; 1H NMR
4.3.29. Compound 5n. 3,5-difluoro-2,6-bis(3-phenoxyphenoxy)-4-[3-
(tri fluoromethyl)phenoxy]benzonitrile
(400 MHz, CDCl3, d ppm): 6.62–6.68 (2H, m), 6.73–6.75 (2H, dd)
7.00–7.02 (2H, d), 7.13–7.17 (3H, m), 7.23–7.25 (2H, m), 7.33–7.37
(2H, t), 7.42–7.44 (2H, d), 7.47–7.51 (2H, t); 19F NMR (376 MHz,
Yield: 80% as white solid; mp: 76.4–87.3 8C; 1H NMR (400 MHz,
CDCl3,
(3H, m), 7.12–7.16 (2H, t), 7.22–7.92 (4H, m), 7.33–7.38 (6H, t),
7.40–7.47 (2H, m); 13C NMR (CDCl3, 100 MHz,
): 106.98, 110.31,
111.84, 113.36, 114.34, 119.17, 119.71, 121.38–121.53, 124.28,
130.18, 130.96, 156.47, 158.08, 159.27; 19F NMR (376 MHz, CDCl3,
d
ppm): 6.64–6.67 (3H, m), 6.74–6.77 (2H, m), 7.04–7.06
CDCl3,
d
ppm): ꢀ62.94 (6F, s), ꢀ138.73 (2F, s). Anal. calcd for
C33H17F8NO4: C, 61.60; H, 2.66; N, 2.18; found: C, 61.69; H, 2.70; N,
d
2.16. ESI-TOF MS for C33H17F8NO4: Calcd: 643.10; found: 688.10
(M+2Na-H).
d
C
ppm): ꢀ62.94 (3F, s), ꢀ139.71 (2F, s). Anal. calcd for
4.3.36. Compound 5u. 2,6-bis[3,5-bis(trifluoromethyl)phenoxy]-3,5-
di-fluoro-4-(3-phenoxyphenoxy)benzonitrile
38H22F5NO5: C, 68.37; H, 3.32; N, 2.10; found: C, 68.75; H,
3.15; N, 2.12. ESI-TOF MS for C38H22F5NO5: Calcd: 667.14; found:
712.14 (M+2Na-H).
Yield: 91% as white solid; mp: 103.4–106.4 8C; 1H NMR
(400 MHz, CDCl3,
d ppm): 6.60–6.63 (1H, m), 6.71–6.72 (1H, t),
6.75–6.78 (1H, dd), 7.01–7.03 (2H, m), 7.14–7.18 (1H, t), 7.26 (1H,
s), 7.34–7.38 (2H, m), 7.43 (4H, s), 7.71 (2H, s); 19F NMR (376 MHz,
4.3.30. Compound 5o. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2,6-diphenoxybenzonitrile
CDCl3,
d
ppm): ꢀ63.19 (12F, s), ꢀ137.20 (2F, s). Anal. calcd for
Yield: 67% as white solid; mp: 101.4–104.7 8C; 1H NMR
C35H15F14NO4: C, 53.93; H, 1.94; N, 1.80; found: C, 54.32; H, 2.28;
(400 MHz, CDCl3,
d
ppm): 7.00–7.02 (4H, d), 7.15–7.19 (2H, t),
ppm):
N, 1.80. ESI-TOF MS for C35H15F14NO4: Calcd: 779.08; found:
824.07 (M+2Na-H).
7.35–7.39 (6H, m), 7.66 (1H, s); 19F NMR (376 MHz, CDCl3,
d
ꢀ63.21 (6F, s), ꢀ139.81(2F, s) Anal. calcd for C27H13F8NO3: C,
58.81; H, 2.38; N, 2.54; found: C, 59.00; H, 2.66; N, 2.59. ESI-TOF MS
for C27H13F8NO3: Calcd: 551.08; found: 596.08 (M+2Na-H).
4.3.37. Compound 6. 4-cyano-2,3,5,6-tetrafluorophenyl benzoate
Yield: 84% as off-white solid; mp: 132.4–138.6 8C; 1H NMR
(400 MHz, CDCl3,
7.65 (2H, t); 19F NMR (376 MHz, CDCl3,
ꢀ134.36 (2F, m), ꢀ159.71 to ꢀ159.84 (2F, m). Anal. calcd for
14H5F4NO2: C, 56.96; H, 1.71; N, 4.75; found: C, 57.20; H, 1.78; N,
d
ppm): 7.47–7.51 (2H, t), 7.61–7.65 (1H, t), 7.61–
4.3.31. Compound 5p. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2,6-bis(3-methylphenoxy)benzonitrile
d
ppm): ꢀ134.24 to
Yield: 70% as white solid; mp: 111.9–117.0 8C; 1H NMR
C
(400 MHz, CDCl3,
6.98 (2H, d), 7.21–7.26 (2H, t), 7.38 (2H, s), 7.66 (1H, s); 19F NMR
(376 MHz, CDCl3,
(1F, s). Anal. calcd for C29H17F8NO3: C, 60.11; H, 2.96; N, 2.42;
found: C, 59.93; H, 2.47; N, 3.02. ESI-TOF MS for C29H17F8NO3:
Calcd: 579.11; found: 642.11 (M+2Na-H).
d
ppm): 2.35 (6H, s), 6.77–6.82 (4H, t), 6.96–
4.98. ESI-TOF MS for C14H5F4NO2: Calcd: 297.04; found: 191.77
(MꢀCO-C6H5).
d
ppm): ꢀ63.30 (6F, s), ꢀ137.11 (1F, s), ꢀ138.90
4.3.38. Compound 7a. 2-cyano-3,4,6-trifluoro-5-phenoxyphenylben-
zoate
Yield: 20% as off-white solid; mp: 175.7–180.2 8C; 1H NMR
(400 MHz, DMSO-d6,
d
ppm): 7.11–7.18 (6H, m), 7.37–7.41(4H, t);
ppm): ꢀ136.98 to ꢀ137.06 (1F,
4.3.32. Compound 5q. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
19F NMR (376 MHz, DMSO-d6,
d
difluoro-2,6-bis[3-(trifluoromethyl)phenoxy]benzonitrile
dd), ꢀ151.33 to ꢀ151.35 (1F, d), ꢀ162.63 to ꢀ162.69 (1F, d). Anal.
calcd for C20H10F3NO3: C, 65.05; H, 2.73; N, 3.79; found: C, 65.88;
H, 2.83; N, 3.58. ESI-TOF MS for C20H10F3NO3: Calcd: 369.29;
found: 264.02 (MꢀCO-C6H5).
Yield: 87% as white sticky solid; 1H NMR (400 MHz, CDCl3,
d
ppm): 7.19–7.22 (1H, m), 7.25–7.27 (3H, m), 7.41 (2H, s), 7.45 (2H,
s), 7.47–7.55 (2H, m), 7.71–7.72 (1H, d); 19F NMR (376 MHz, CDCl3,
d
ppm): ꢀ63.21 (6F, s), ꢀ63.30 (6F, s), ꢀ140.17(2F, s). Anal. calcd
for C29H11F14NO3: C, 50.67; H, 1.61; N, 2.04; found: C, 50.70; H,
1.74; N, 2.21. ESI-TOF MS for C29H11F14NO3: Calcd: 687.05; found:
732.05 (M+2Na-H).
4.3.39. Compound 7b. 2-cyano-3,4,6-trifluoro-5-[3-(trifluoromethyl)
phenoxy]phenylbenzoate
Yield: 48% as pale brownish solid; mp: 112.8–124.3 8C; 1H
NMR (400 MHz, DMSO-d6,
d ppm): 7.4–7.51 (3H, m), 7.54–7.57
4.3.33. Compound 5r. 4-[3,5-bis(trifluoromethyl)phenoxy]-3,5-
difluoro-2,6-bis(3-phenoxyphenoxy)benzonitrile
(4H, m), 7.61–7.65 (2H, m); 19F NMR (376 MHz, DMSO-d6,
d
ppm): ꢀ61.25 (3F, s), ꢀ136.59 to ꢀ136.68 (1F, dd), ꢀ151.20 to
ꢀ151.24 (1F, dd), ꢀ162.46 to ꢀ162.51 (1F, d). Anal. calcd for
C21H9F6NO3: C, 57.68; H, 2.07; N, 3.20; found: C, 57.10; H, 1.90;
N, 3.29. ESI-TOF MS for C21H9F6NO3; Calcd: 437.29; found:
332.01(MꢀCO-C6H5).
Yield: 48% as white solid; mp: 84.7–89.5 8C; 1H NMR
(400 MHz, CDCl3,
d ppm): 6.63–6.66 (2H, dd), 6.69 (2H, b),
6.75–6.78 (2H, dd), 7.03–7.05 (4H, d), 7.13–7.16 (2H, t), 7.25–
7.29 (2H, t), 7.34–7.38 (6H, m), 7.66 (1H, s); 19F NMR (376 MHz,

R. Krishnan, A. Parthiban / Journal of Fluorine Chemistry 162 (2014) 17–25
25
[9] (a) I.S. Ali, A. Sudalai, Tetrahedron Lett. 43 (2002) 5435–5436;
4.3.40. Compound 7c. 3-[3,5-bis(trifluoromethyl)phenoxy]-6-cyano-
2,4,5-triflourophenylbenzoate
(b) M. Srebnik, P.V. Ramachandran, H.C. Brown, J. Org. Chem. 53 (1988) 2916–
2920.
[10] G. Broggini, G. Molteni, A. Terraneo, G. Zecchi, Tetrahedron 55 (1999) 14803–
14806.
Yield: 52% as brownish solid; mp: 161.0–171.9 8C; 1H NMR
(400 MHz, DMSO-d6,
d
ppm): 7.86 (2H, s), 7.90 (2H, s), 7.93–7.98
ppm): ꢀ61.60 (6F, s),
[11] (a) G.Y. Mitronova, V.N. Belov, M.L. Bossi, C.A. Wurm, L. Meyer, R. Medda, G.
Moneron, S. Bretschneider, C. Eggeling, S. Jakobs, S.W. Hell, Chem. Eur. J. 16 (2010)
4477–4488;
(b) J. Toyohara, A. Hayashi, A. Gogami, M. Hamada, Y. Hamashima, T. Katoh, M.
Node, Y. Fujibayashi, Nuclear Med. Biol., 33 (2006) 751–764;
(c) S. Singh, A. Aggarwal, S. Thompson, J.P.C. Tome´, X. Zhu, D. Samaroo, M. Vinodu,
R. Gao, C.M. Drain, Bioconjug. Chem. 21 (2010) 2136–2146.
[12] (a) M.P. Krafft, Adv. Drug Deliv. Rev. 47 (2001) 209–228;
(b) S. Henry, D.V. McAllister, M.G. Allen, M. Prausnitz, J. Pharm. Sci. 87 (1998)
922–925.
[13] (a) S. Langereis, J. Keupp, J.L.J. van Velthoven, I.H.C. de Roos, D. Burdinski, J.A.
Pikkemaat, H. Gru¨ ll, J. Am. Chem. Soc. 131 (2009) 1380–1381;
(b) H. Komatsu, T. Miki, D. Citterio, T. Kubota, Y. Shindo, Y. Kitamura, K. Oka, K.
Suzuki, J. Am. Chem. Soc. 127 (2005) 10798–10799;
(c) M.M. Bailey, C.M. Mahoney, K.E. Dempah, J.M. Davis, M.L. Becker, S. Khondee,
E.J. Munson, C. Berkland, Macromol. Rapid Commun. 31 (2010) 87–92.
[14] (a) V. Percec, M. Glodde, T.K. Bera, Y. Miura, I. Shiyanovskaya, K.D. Singer, V.S.K.
Balagurusamy, P.A. Heiney, I. Schnell, A. Rapp, H.-W. Spiess, S.D. Hudson, H. Duan,
Nature 417 (2002) 384–387;
(4H, m); 19F NMR (376 MHz, DMSO-d6,
d
ꢀ137.18 to ꢀ137.26 (1F, m), ꢀ152.06 (1F, b), ꢀ165.44 (1F, b). Anal.
calcd for C22H8F9NO3: C, 52.29; H, 1.60; N, 2.77; found: C, 52.20; H,
2.08; N, 2.98. ESI-TOF MS for C22H8F9NO3: Calcd: 505.28; found:
400.01(MꢀCO-C6H5).
4.3.41. Compound 7d. 2-cyano-3,4,6-trifluoro-5-(3-
phenoxyphenoxy) phenylbenzoate
Yield: 46% as pale brownish sticky solid; 1H NMR (400 MHz,
DMSO-d6,
7.05 (3H, d), 7.16–7.19 (2H, t), 7.34–7.43 (6H, m); 19F NMR
(376 MHz, DMSO-d6,
d ppm): 6.72–6.74 (1H, dd), 6.84–6.89 (2H, m), 7.03–
d
ppm): ꢀ136.84 to ꢀ136.93 (1F, dd),
ꢀ151.37 (1F, b), ꢀ162.68 (1F, b). Anal. calcd for C26H14F3NO4: C,
67.68; H, 3.06; N, 3.04; found: C, 67.82; H, 3.15; N, 3.34. ESI-TOF MS
for C26H14F3NO4; Calcd: 461.38; found: 356.05 (MꢀCO-C6H5).
(b) R. Schmidt, M.M. Ling, J.H. Oh, M. Winkler, M. Ko¨nemann, Z. Bao, F. Wu¨rthner,
Adv. Mater. 19 (2007) 3692–3695.
[15] (a) B. Boutevin, P. Yves, Prog. Org. Coat. 13 (1985) 297–331;
(b) V.C. Malshe, S.N. Sangaj, Prog. Org. Coat. 53 (2005) 207–211.
[16] (a) J.B. Rose, Polymer 15 (1974) 456–465;
Acknowledgments
(b) M. Ohno, T. Takata, T. Endo, J. Polym. Sci. Polym. Chem. Ed. 33 (1995) 2647–
2655;
(c) P.M. Hergenrother, J.W. Connell, J.W. Labadie, J.L. Hedrick, Adv. Polym. Sci. 117
(1994) 67–110;
(d) V. Percec, J.H. Wang, R.S. Clough, Makromol. Chem. Macromol. Symp. 54/55
(1992) 275–312;
(e) S. Chatti, M.A. Hani, K. Bornhorst, H.R. Kricheldorf, High Perf. Polym. 21 (2009)
105–118;
This work was funded by the Agency for Science, Technology
and Research (A*STAR, ICES/10-545A01), Singapore under ‘‘Inte-
grative Approach for 10Tb/in2 Magnetic Recording Research
Program’’. The authors thank Ms. Chen Junhui and Ms. Foo Ming
Choo for technical assistance and Dr. Chacko Jacob for 19F NMR
analyses.
(f) Z. Li, J. Ding, G.P. Robertson, M.D. Guiver, Macromolecules 39 (2006) 6990–
6996;
(g) V.L. Rao, P.U. Sabeena, K.N. Ninan, Eur. Polym. J. 34 (1998) 567–570;
(h) M. Jikei, H. Itoh, N. Yoshida, Y. Inai, T. Hayakawa, M.A. Kakimoto, J. Polym. Sci.
A: Polym. Chem. 47 (2009) 5835–5844;
Appendix A. Supplementary data
(i) A. Saxena, V.L. Rao, G.V. Asari, K.N. Ninan, J. Polym. Mater. 21 (2004) 343–350;
(j) A. Parthiban, A. Le Guen, Y. Yansheng, U. Hoffmann, M. Klapper, M. Muellen,
Macromolecules 30 (1997) 2238–2243.
Supplementarymaterialrelatedtothisarticlecanbefound, inthe
online version, at http://dx.doi.org/10.1016/j.jfluchem.2014.03.005.
[17] (a) Z. Baolong, A. Clearfield, J. Am. Chem. Soc. 119 (1997) 2751–2752;
(b) R. Berger, G. Resnati, P. Metrangolo, E. Weber, J. Hulliger, Chem. Soc. Rev. 40
(2011) 3496–3508;
References
(c) R.D. Chambers, P.R. Hoskin, A.R. Kenwright, A. Khalil, P. Richmond, G. Sand-
ford, D.S. Yufit, J.A.K. Howard, Org. Biomol. Chem. 1 (2003) 2137–2147;
(d) C.A. Hargreaves, G. Sandford, B.G. Davis, in: V.A. Soloshonok (Ed.), Current
Fluoroorganic Chemistry, ACS Symposium Series 949 (Washington, DC), 2007, pp.
323–336.
[1] (a) N.-J. Lin, H.-S. Yang, Y. Chang, K.-L. Tung, W.-H. Chen, H.-W. Cheng, S.-W.
Hsiao, P. Aimar, K. Yamamoto, J.-Y. Lai, Langmuir 29 (2013) 10183–10193;
(b) M. Pagliaro, R. Ciriminna, J. Mater. Chem. 15 (2005) 4981–4991;
(c) X. Zhang, F. Shi, J. Niu, Y. Jiang, Z. Wang, J. Mater. Chem. 18 (2008) 621–633.
[2] (a) B.S. Nader, K.K. Kar, T.A. Morgan, C.E. Pawloski, W.L. Dilling, Tribol. Trans. 35
(1992) 37–44;
[18] (a) H. Berber, T. Brigaud, O. Lefebvre, R. Plantier-Royon, C. Portella, Chem. Eur. J. 7
(2001) 903–909;
(b) H.I. Kim, T. Koini, T. Randall Lee, S.S. Perry, Langmuir 13 (1997) 7192–7196;
(c) W. Liu, C. Ye, Y. Chen, Z. Ou, D.C. Sun, Tribol. Int. 35 (2002) 503–509.
[3] (a) G.S. Lal, G.P. Pez, R.J. Pesaresi, F.M. Prozonic, H. Cheng, J. Org. Chem. 64 (1999)
7048–7054;
(b) T. Miura, Y. Hirose, M. Ohmae, T. Inazu, Org. Lett. 3 (2001) 3947–3950;
(c) S.J. Williams, S.G. Withers, Carbohydr. Res. 327 (2000) 27–46.
[19] (a) J.E. Anthony, Chem. Rev. 106 (2006) 5028–5048;
(b) R.D. Chambers, M.J. Seabury, D.L.H. Williams, N. Hughes, J. Chem. Soc. Perkin
Trans. 1 (1988) 251–254;
(c) W. Wu, Y. Liu, D. Zhu, Chem. Soc. Rev. 39 (2010) 1489–1502.
[20] (a) M.R. Cargill, K.E. Linton, G. Sandford, D.S. Yufit, J.A.K. Howard, Tetrahedron 66
(2010) 2356–2362;
(b) A. Santra, I. Senkovska, S. Kaskel, P.K. Bharadwaj, Inorg. Chem. 52 (2013)
7358–7366;
(c) W. Kaminsky, S. Lenk, V. Scholz, H.W. Roesky, A. Herzog, Macromolecules 30
(1997) 7647–7650.
[4] (a) J. Kim, S.H. Kim, T.K. An, S. Park, C.E. Park, J. Mater. Chem. C 1 (2013) 1272–
1278;
(b) A.O. Miller, G.G. Furin, J. Fluor. Chem. 75 (1995) 169–172;
(c) C.J. Drayton, W.T. Flowers, R.N. Haszeldine, W.D. Morton, J. Chem. Soc. Perkin
Trans. 1 (1975) 1035–1040;
(b) B. Stadlober, M. Zirkl, M. Beutl, G. Leising, S. Bauer-Gogonea, S. Bauer, Appl.
Phys. Lett. 86 (2005) 242902;
(c) G. Hougham, G. Tesoro, A. Alfred Viehbeck, Macromolecules 29 (1996) 3453–
3456.
(d) R. Krishnan, A. Parthiban, J. Polym. Res. 20 (2013) 230 (1–8).
[21] (a) S. Rudiger, K. Seppelt, J. Fluor. Chem. 82 (1997) 25–28;
(b) P.M. Budd, B.S. Ghanem, S. Makhseed, N.B. McKeown, K.J. Msayib, C.E.
Tattershall, Chem. Commun. (2004) 230–231.
[22] (a) A. Parthiban, F. Ming Choo, C.L.L. Chai, Polym. Int. 60 (2011) 1624–1628;
(b) A. Parthiban, F. Ming Choo, J. Polym. Res. 19 (2012) 9762–9768;
(c) A. Parthiban, T.R. Babu Rao, Polym. Preprints 48 (2007) 541–542;
(d) A. Parthiban, H. Yu, C.L.L. Chai, Polym. Preprints 50 (2009) 479–480;
(e) A. Parthiban, H. Yu, C.L.L. Chai, Polym. Preprints 50 (2009) 729–730;
(f) A. Parthiban, M. Venugopal, U.S. Patent Application Publication (2006)
US2006189774 A1 20060824.
[5] (a) D. Pauluth, K. Kazuaki Tarumi, J. Mater. Chem. 14 (2004) 1219–1227;
(b) F. Babudri, G.M. Farinola, F. Naso, R. Ragni, Chem. Commun. (2007) 1003–
1022;
(c) S. Sergeyev, W. Pisula, Y.H. Geerts, Chem. Soc. Rev. 36 (2007) 1902–1929;
(d) F. Guittard, E. Taffin de Givenchy, S. Geribaldi, A. Cambon, J. Fluor. Chem. 100
(1999) 85–96.
[6] (a) H.B. Borate, S.P. Sawargave, S.P. Chavan, M.A. Chandavarkar, R. Iyer, A. Tawte,
D. Rao, J.V. Deore, A.S. Kudale, P.S. Mahajan, G.S. Kangire, Bioorg. Med. Chem. Lett.
21 (2011) 4873–4878;
(b) V.S. Pore, M.A. Jagtap, S.G. Agalave, A.K. Pandey, M.I. Siddiqi, V. Kumar, P.K.
Shukla, Med. Chem. Commun. 3 (2012) 484–488.
[7] C. Heidelberger, N.K. Chaudhuri, P. Danneberg, D. Mooren, L. Griesbach, R.
Duschinsky, R.J. Schnitzer, E. Pleven, J. Scheiner, Nature 179 (1957) 663–
666.
[23] (a) R. Dawson, F.B. Su, H.J. Niu, C.D. Wood, J.T.A. Jones, Y.Z. Khimyak, A.I. Cooper,
Macromolecules 41 (2008) 1591–1593;
(b) W.G. Lu, D.Q. Yuan, D. Zhao, C.I. Schilling, O. Plietzsch, T. Muller, S. Brase, J.
Guenther, J. Blumel, R. Krishna, Z. Li, H.C. Zhou, Chem. Mater. 22 (2010) 5964–
5972;
(c) J. Germain, J. Hradil, J.M.J. Frechet, F. Svec, Chem. Mater. 18 (2006) 4430–
4435;
´
´
´
´
ˇ
´
´
´
[8] (a) I.V. Micovic, G.M. Roglic, M.D. Ivanovic, L. Dosen-Micovic, V.D. Kiricojevic, J.B.
Popovic´, J. Chem. Soc. Perkin Trans. 1 (1996) 2041–2050;
(b) T.T. Conway, A. Shoeb, L. Bauer, J. Pharm. Sci. 57 (1968) 455–459.
(d) J.X. Jiang, F. Su, A. Trewin, C.D. Wood, H. Niu, J.T.A. Jones, Y.Z. Khimyak, A.I.
Cooper, J. Am. Chem. Soc. 130 (2008) 7710–7720.