Highly selective detection of fluoride based on 2,2-diferrocenylpropane benzimidazolium borate-ester salt

Article abstract of DOI:10.1016/j.tetlet.2016.02.019

A new anion receptor that utilized boron-fluoride interaction and (C-H)⁺?F^--type ionic hydrogen bonding in the binding of F ions had been synthesized and characterized by IR, MS, HRMS, ¹¹B, ¹H, and ¹³

Full text of DOI:10.1016/j.tetlet.2016.02.019

Accepted Manuscript
Highly Selective Detection of Fluoride Based on 2,2-Diferrocenylpropane Ben-
zimidazolium Borate-ester Salt
Zhi-Ming Su, Xi-Quan Yan, Chao-Li Liang, Cai-Xia Lin, Li-Li Xie, Yao-Feng
Yuan
PII:
S0040-4039(16)30129-0
DOI:
http://dx.doi.org/10.1016/j.tetlet.2016.02.019
TETL 47292
Reference:
Tetrahedron Letters
To appear in:
Received Date:
Revised Date:
Accepted Date:
12 December 2015
30 January 2016
3 February 2016
Please cite this article as: Su, Z-M., Yan, X-Q., Liang, C-L., Lin, C-X., Xie, L-L., Yuan, Y-F., Highly Selective
Detection of Fluoride Based on 2,2-Diferrocenylpropane Benzimidazolium Borate-ester Salt, Tetrahedron Letters
(2016), doi: http://dx.doi.org/10.1016/j.tetlet.2016.02.019
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1
Tetrahedron Letters
Highly Selective Detection of Fluoride Based on 2,2-Diferrocenylpropane
Benzimidazolium Borate-ester Salt
Zhi-Ming Sua, , Xi-Quan Yana, Chao-Li Lianga, Cai-Xia Lina, Li-Li Xiea, Yao-Feng Yuana,b,*
a Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350116, China
b State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002,
China
AR T IC LE IN FO
AB STR AC T
Article history:
Received
Received in revised form
Accepted
A new anion receptor that utilized boron-fluoride interaction and (C-H)+ …F--type ionic hydrogen
1
bonding in the binding of F ions had been synthesized and characterized by IR, MS, HRMS, 11B, H
and 13C NMR spectra. The signaling process was confirmed by UV-vis, electrochemistry
1
measurements as well as H, 19F and 11B NMR spectroscopy. Among the tested anions: F-, Cl-, Br-,
-
-
Available online
OAc-, H2PO4 , HSO4 , only F- induced a remarkable red-shift (29nm) in the absorption spectrum which
was concomitant with a color change from pink to faint yellow. This receptor provided a new
approach for naked-eyed detection of F- and the detection limit was calculated to be 1.26µM. Besides,
Cyclic Voltammetry (CV) showed that the receptor had unique selectivities for F- with a remarkable
phenomenon in merging of the two reduction peaks in response to the increment addition of the
anions. 1H, 19F and 11B NMR titrations demonstrated that the receptor showed affinity and high
selectivity for F- and provided the evidence of interaction between the receptor and F-.
Keywords:
Anion Receptor
Fluoride Detection
Electrochemistry
UV-vis
2009 Elsevier Ltd. All rights reserved.
1H NMR titration
Anions are ubiquitous in the real world and play a
fundamental role in a wide range of chemical and biological
processes, and considerable effort has been devoted to the
development of abiotic receptors for anionic species.1 Among
the different anions, fluoride is the smallest anion with a high
charge density and a hard Lewis basic nature, which results in
unusual chemical properties.2 The fluoride ion is widely used
in a number of applications such as dental care, treatment of
osteoporosis, fluoridation of water supplies, etc. However,
excess fluoride exposure may lead to dental and skeletal
fluorosis, neurological damages, gastric and kidney
problems.3 In this sense, design and synthesis of abiotic
receptors for fluoride ion is of great importance.4
In a number of cases, the imidazolium/benzimidazolium
group5 is an attractive building block for fluoride receptors
because strong attractive electrostatic forces in positively
charged hosts are also of significant importance to the fluoride
recognition process. Various signaling groups, such as optical,
fluorescent or electrochemical sensing units6 have been
installed on imidazolium/benzimidazolium receptors to realize
the convenient detection of fluoride. Electron-deficient Lewis
acid coordination by orbital overlap has also received
considerable attention and receptors containing boron7 or
silicon8 utilize the characteristic as binding mechanism to
realize the purpose of recognizing fluoride.9 Despite the
growing interest, the development of fluoride receptors in
________________________
 Corresponding author. Tel: (+86) 591 22866161; fax: (+86) 591 22866161.; e-mail: yaofeng_yuan@fzu.edu.cn

2
Tetrahedron
general has been particularly challenging and F- receptors
with good preorganization and multifunctionality are
nevertheless quite rare and still highly desirable.10
The β-hydroxy ketone product of an aldol reaction could
undergo dehydration to give an α,β-unsaturated product 2.
Ferrocene based receptors are of great interest for
chemosensors due to their electrochemistry sensing abilities
toward anions and these receptors are expected to show
cathodic shifts in their redox process on complexation to an
anion, as they are easier to oxidize or harder to reduce than a
free redox-active receptor. The shifting magnitude of potential
represents the response level of anion recognition.11 2,2-
Diferrocenylpropane (DFP), synthesized from ferrocene and
acetone, is one of the most important building blocks for
preparation of multiferrocenyl derivatives because it
contributes two pairs of redox peaks as signaling subunits.12
Recently, A survey of literature reveals that identify units,
containing ferrocenyl unit and various recognition units
including urea, thiourea, pyrrole, amide and imidazole, have
been designed and synthesized.13 However, it seems rather
rare to incorporate redox-active group and Lewis-acidic boron
group14 and benzimidazolium group in one molecule to allow
both electrochemical and optical sensing output for F-. Herein,
we have designed the receptor utilizing a new molecule of
multi-signaling sensing for fluoride ion, which potential as
receptor has been explored using variou anions, with special
attention towards high selectivity for F- ion.
Scheme 1. Synthetic procedure of receptor 1.
The receptor 1 was synthesized from the reaction of
compound 2 and [3-(Bromomethyl)phenyl]ethylenboronate in
anhydrous CH3CN. The solvent was evaporated to dryness.
The residue was dissolved in CH3OH and a saturated solution
of NH4PF6 was added to get compound 1. Analysis of
1
receptor 1 by H NMR spectroscopy showed a characteristic
singlet of the C-2 proton of the benzimidazolium at δ: 10.79
ppm, as well as a characteristic doublet of the boric acid ester
group at δ: 3.17 ppm (see Supplementary data, Fig. S1). The
receptor 1 displayed broad 11B NMR signal at 31 ppm as
showed in Fig S2 (see Supplementary data).
Fluorescence changes of receptor 1 (c = 5×10-5 M) in
CH3CN upon addition of anions (F-, Cl-, Br-, AcO-, HSO4 ,
-
-
As depicted in Scheme 1, the target molecule was
and H2PO4 ) were investigated. Contrasting to many
synthesized
starting
from
2,2-
fluorescent chemosensors of anion, in the present work, the
fluorescence was “switched on” upon recognition rather than
“switched off” as reported in most literature cases. This could
be understood, however, on the basis of ferrocene and
ferrocenyl derivatives were classical quenchers of exicted
states involving either energy or electron transfer. Addition of
diferrocenylpropanecarboxaldehyde 4, which was prepared
via formylation reaction from 2,2-diferrocenylpropane 5 with
DMF,12b and 1-(4-acetylphenyl)-1H-benzimidazole 3 was
obtained by Cu(I)-catalyzed N-arylation of benzimidazole
with 1-(4-bromophenyl)ethanone from the literature method.15

3
-
-
anions might inhibit the quenching process so as to allow
fluorescence of the receptor to be restored. In the case of
receptor 1, fluorescence was observed with a maximum
emission band at 307nm (see Supplementary data, Fig. S4).
After addition of 10 equivalents of various anions such as Cl-,
HSO4 and H2PO4 , while there was a slight spectral change of
red-shift (Δλ = 6 nm) from 333 nm to 339 nm in the presence
of AcO-, and a larger spectral change of red-shift (Δλ = 29 nm)
in the presence of F- from 333nm to 362nm as well as a larger
spectral change of blue-shift (Δλ = 30 nm) from 527nm to
497nm. As showed in Figure 2, there were three UV-vis
absorption spectral peeks obviously changed with the addition
of various amounts of F ion, which were 270nm, 333nm and
527nm. The stoichiometry between receptor 1 and F- was
determined from the UV-vis titration data. The measured
absorbance variation from 333 nm to 362 nm (△A = Ai ─ A0)
reached maximum values when the molar fraction of ([F-]/[1]
+ [F-]]) was 0.5, which indicated that receptor 1 and F- formed
a 1:1 complexes in Fig. S5 (see Supplementary data). As
showed in Scheme 2, the reaction mechanism was proposed
between receptor 1 and F- based on the Job plots, which
similarly had been reported by Yoon and coworkers.5b,5c
-
Br- and HSO4 , it was observed that receptor 1 caused nearly
-
no change in fluorescence, while F-, AcO- and H2PO4 induced
fluorescence enhancement. The stronger fluorescence
enhancement induced by F- ion allowed discrimination from
other anions.
To further investigate the optical properties of receptor
1,UV-vis spectra changes of receptor 1 (c = 5×10-5 M) in
-
CH3CN upon addition of anions (F-, Cl-, Br-, AcO-, HSO4 ,
-
and H2PO4 ) were carried out.
1.8
362nm
1.6
1+Br
1+H SO 4
1+F
1+Cl
1+H 2PO 4
1+O Ac
1
270nm
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
339nm
0.20
receptor
1.8
497nm
362nm
receptor+10F-
0.15
receptor+10OAc-
1.6
receptor
270nm
receptor+10H2PO4-
527nm
receptor+1F-
333nm
272nm
0.10
1.4
receptor+10HSO4-
receptor+10Cl-
receptor+10Br-
527nm
receptor+2F-
497nm
1.2
receptor+3F-
0.05
receptor+4F-
1.0
0.00
receptor+5F-
receptor+6F-
receptor+7F-
receptor+8F-
receptor+9F-
receptor+10F-
receptor+20F-
450
500
550
600
650
700
250 300 350 400 450 500 550 600 650 700 750 800
Wavenumber/nm
0.8
0.6
0.4
0.2
0.0
Wavenumber/nm
333nm
272nm
Figure 1. UV-vis absorption spectra of receptor 1 (5 × 10-5 mol L-1 in
CH3CN) in the presence of 10 equivalents of various anions. Inset :
Color changes of receptor 1 (c = 5×10-5 mol L-1) in CH3CN after
addition of 2 equivalent of various anions.
250
300
350
400
450
500
550
600
650
700
Wavenumber/nm
Figure 2. UV-Vis absorption spectra of receptor 1 (5 × 10 -5 mol L-1
The receptor 1 displayed high selectivity for F- ion over
other anions, as evidenced by the rapid color changes from
pink to faint yellow, while other anions caused no change (Cl-,
in CH3CN) after addition of various amounts of F- ion.
To address the sensitivity of receptor 1 towards F- sensing,
we had carried out UV-vis titration of receptor 1 (50 µM) in
CH3CN with F- (62.5 mM). Detection limit for F- was
calculated using UV titrations and equation, detection limit =
3σ/m, where σ = standard deviation of 5 blank measurements
and m = slope obtained from the graph of △A (△A = Ai ─ A0)
-
-
Br-, HSO4 , H2PO4 , AcO-) in color (Figure 1 (inset)). Figure 1
exhibited the UV-vis spectra changes of receptor 1 towards 10
equivalents of various anions. The receptor 1 showed almost
no change in absorption peak in the presence of Cl- , Br-,

4
Tetrahedron
intensity Vs concentration of F- added. The detection limit of
receptor 1 towards F- was evaluated to be 1.26 µM (24.0 ppb)
(see Supplementary data, Fig. S6), which was well below 4
ppm, the allowed concentration level of F- in drinking water
specified by the USEPA2e.
absorption spectral peaks changed by increasing the amount
of water, for example, 20% aqueous solution of CH3CN: H2O
= 80: 20, there were two changes of red-shift (Δλ = 7 nm)
from 362nm to 369nm and (Δλ = 11 nm) from 497nm to
508nm, respectively. However, the color was not changed in
the presence of F- upon the addition of 20% aqueous solution
of CH3CN: H2O = 80: 20 (Figure 3b). From the results we
could draw the conclusion that proposed reaction mechanism
(Scheme 2) was irreversible.
1.8
A
497nm
362nm
0.20
0.15
0.10
0.05
0.00
527nm
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
270nm
509nm
receptor
receptor+10F
receptor+10F+1%H2O
333nm
369nm
receptor+10F+2%H2O
450
500
550
600
650
700
750
800
receptor+10F+3%H2O
receptor+10F+4%H2O
receptor+10F+5%H2O
receptor+10F+7%H2O
receptor+10F+10%H2O
receptor+10F+15%H2O
receptor+10F+20%H2O
Wavenumber/nm
Figure 4 showed that the receptor 1 alone exhibited two
reversible redox waves (ΔE1 = 72 mV and ΔE2 = 62 mV),
characteristic for ferrocene derivatives. Upon the addition of
F- ion to the the CH3CN solutions of receptor 1, it caused a
distinct behavior in the CV. For example, when the increment
of the F- ion was 4 equivalents, the CV behavior compared
with the receptor 1 alone (Epa1= 710 mV, Epa2 = 458 mV, Epc1
= 638 mV, Epc2 = 396 mV) had only one reduction peak (Epc =
348 mV), while the oxidation peak still had two (Epa1= 673
mV and Epa2 = 438 mV) with ΔEpa1 = -37 mV and ΔEpa2 = -20
mV versus receptor 1 alone. Then with the increase in F- ions,
the CV behavior still had one reduction peak (Epc = 328 mV)
and two oxidation peaks (Epa1= 658 mV and Epa2 = 433 mV),
in which there were a larger cathodic shift of ΔEpa1 = -57 mV
and ΔEpa2 = -25 mV versus receptor 1 alone. The
electrochemical changes of CV curves of receptor 1 upon
addition of various anions were illustrated in Figs. S7-S10
(see Supplementary data). The results of the electrochemical
272nm
250 300 350 400 450 500 550 600 650 700 750 800 850
Wavenumber/nm
B
Figure 3. (A) UV-Vis absorption spectra of receptor 1 (5 × 10 -5 mol
L-1 in CH3CN) with 10 equivalents’ F- ion by increasing the amount
of water gradually; (B) Color changes of receptor 1 (c = 5×10-5 mol
L-1) in CH3CN with 2 equivalent of various anions upon the addition
of 20% aqueous solution of CH3CN: H2O = 80: 20.
Scheme 2. The proposed mechanism of receptor 1 towards F- ion
based on the Job plots in CH3CN.
Experiments were explored by increasing the amount of
water gradually such as 1%, 2%, 3%, 4%, 5%, 7%, 10%, 15%
and 20% aqueous solution on the basis of receptor 1 (5 × 10 -5
mol L-1 in CH3CN) with 10 equivalents’ F- ion. As could be
seen from Figure 3a, there were mainly two UV-vis
analysis of receptor
1 were listed in table 1 (see
Supplementary data) upon addition of 6 equivalents of various
anions. The shift magnitude of ΔEp values followed the order
-
F- > AcO- > HSO4 ≈ Br- ≈ Cl-, from the results we could draw

5
the conclusion that the receptor 1 showed affinity and high
redox peaks ( Epa1 = 693 mV, Epa2 = 403 mV, Epc1 = 561 mV,
selectivity for F- ion in electrochemical behaviors.
Epc2 = 326 mV ) were different from the receptor 1 alone (Epa1
= 710 mV, Epa2 = 458 mV, Epc1 = 638 mV, Epc2 = 396 mV ) in
CH3CN, as listed in Table 2 (see Supplementary data). The
CV behavior indicated that the complexation process between
the receptor 1 and F- ion was irreversible due to the strong
interaction between borate-ester and fluoride ion.
1.0x10-5
5.0x10-6
0.0
receptor
receptor+1F-
receptor+2F-
receptor+3F-
receptor+4F-
receptor+5F-
receptor+6F-
-5.0x10-6
-1.0x10-5
In order to explain the electrochemical behaviors, we
brought forward the model of receptor 1 towards F- ion based
on the electrochemical data. Figure 6 showed that the redox
peak for receptor 1 with the increasement F- ion was cathodic
shift in anhydrous CH3CN because of strong interactions
taking place between Lewis-acid boron and F- ion as well as
hydrogen bonding, including the C-H of ferrocene, which had
been reported and well illustrated that C-H of ferrocene had
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Potential/V
Figure 4. CV of receptor 1 (c = 2.5×10-4 M) in CH3CN on addition
of various concentrations of F- ion.
receptor
receptor+10F
1.5x10-5
1.0x10-5
receptor+10F+1%H2O
receptor+10F+2%H2O
receptor+10F+3%H2O
receptor+10F+4%H2O
receptor+10F+5%H2O
5.0x10-6
0.0
-
-
hydrogen bonding with other anions,16 such as BF4 , H2PO4 ,
OAc-. And by increasing the amount of water, since water
competed with the hydrogen bonding of fluoride towards
receptor 1, the redox peak should be similar to the receptor 1
alone, however the strong interaction between Lewis-acid
boron and F- made its chemical structure essentially different
from receptor 1, resulted in the different redox potential as
showed in Figure 4.
-5.0x10-6
-1.0x10-5
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Potential/V
Figure 5. CV of receptor 1 (c = 2.5×10-4 M) in CH3CN with 10
equivalents’ F- ion by increasing the amount of water.
Experiments on CV were also explored by increasing the
amount of water gradually such as 1%, 2%, 3%, 4%, 5%
aqueous solution on the basis of receptor 1 with 10
equivalents’ F- ion. As could be seen from Figure 5, the CV
behavior of receptor 1 was changed by increasing the amount
of water, for example, in 2% aqueous solution there was two
oxidation peaks (Epa1= 663 mV and Epa2 = 413 mV), while
there were three reduction peaks (Epc1 = 538 mV, Epc2 = 338
mV and Epc3 = 278 mV), indicating an intermediate state of
interaction among receptor 1 and fluoride ion and water.
There was no significant change in redox peaks compared
with receptor 1 alone in the 5% aqueous solution, however the
Figure 6. The proposed electrochemistry model of receptor 1
towards F- ion in CH3CN upon the addition of water.

6
Tetrahedron
1
To gain more insight into the anion recognition properties
C-2 proton. From H NMR spectra, we could draw the
1
of receptor 1, H , 19F and 11B NMR titration experiments
conclusion that receptor 1 displayed selectivity for F- ion over
-
were carried out by adding tetrabutyl-ammonium salts of the
other anions in the order F- > AcO- > Cl- > Br- > HSO4 , which
-
anions (TBAX, where X = F-, Cl-, Br-, AcO- and HSO4 ) to the
was similarly consistent with the UV-vis and electrochemical
results.
receptor 1 (c = 5×10-3 M, DMSO-d6) solution. H2PO4 was not
-
1
included due to the occurrence of precipitation during H
NMR titration.
Figure 7 showed that the intensity of the benzimidazolium
C-H resonance decreased gradually and disappeared followed
upon addition of F- ions, suggesting that complexation of the
F- ion is associated with the C-H hydrogen bonding. And there
were four kinds of protons showing obvious highfield shifts
for receptor 1, i.e., the proton (H2 and H3) of benzimidazolium;
the proton (H8, H9 and H11) of the phenyl group of boronate-
ester, the protons (H12) of methylene and the proton (H13 and
H14) of ferrocenyl group. The highfield shifts of the four kinds
of protons indicated the existence of interactions between the
receptor 1 and the F- ion in DMSO-d6 solution. And it had a
1
Figure 7. H NMR spectra of receptor 1 (c = 5×10-3 M) in
DMSO-d6 upon the addition of various concentrations of F-
ion.
In order to explain the (C-H)+…F- hydrogen bonding and
Lewis-acidic boron with the fluoride ion, we also utilized the
19F and 11B NMR spectra. As could be seen from Figure 8, the
-
triplet around 16 ppm for the HF2 ion, indicating
-
19F NMR of PF6 of the receptors 1 (-69.19 ppm and 71.06
deprotonation and fluoride ion mediated hydrogen-deuterium
exchanges.17 Different from F- ions, the proton (H2 and H3) of
benzimidazolium and the proton of the phenyl group of
boronate-ester showed highfield shifts for receptor 1 upon
addition of OAc- ions as shown in Fig. S11 (see
Supplementary data), however, the protons (H12) of methylene
and the proton (H13 and H14) of ferrocenyl group had no shift
ppm) was not changing upon the addition of TBAF, because
-
the anion of PF6 had been combined with the receptor 1. And
we could capture the the gradual downfield shifts of TBAF,
from -100.46 ppm to -104.00 ppm and -142.62 ppm to -
143.05 ppm, respectively, suggesting that the F- ions had the
existence of interaction with receptor 1, associated with the C-
H hydrogen bonding. The peak at -133.62 ppm appeared upon
the addition of F- ions and was corresponded to B-F
interaction, which similarly had been confirmed by Yoon and
co-workers.5c As shown in Figure 9, the peaks at 31.54 and
2.86 ppm, appeared upon the addition of F- and was
1
change essentially. H NMR spectra of receptor 1 upon the
addition of other anions was illustrated in Fig. S12-S14 (see
-
Supplementary data). The Br-, Cl- and HSO4 had little effect
on the receptor 1. Fig. S15 (see Supplementary data) showed
the titration curves of receptor 1 obtained by monitoring the

7
corresponded to -11B(OCH2CH2O) and -11B(OCH2CH2O)F-,
which similarly had been confirmed by Chen and co-
recognition properties toward a series of common anions.
-
-
Among the tested anions: F-, Cl-, Br-, OAc-, H2PO4 , HSO4 ,
only F- induced a remarkable red-shift (29nm) in the
absorption spectrum which was concomitant with a color
change from pink to faint yellow. This receptor provided a
new approach for naked-eyed detection of F- and the detection
limit was calculated to be 1.26µM. Besides the Job plots for
receptor 1 with F- ion by UV-vis showed maxima at 0.5 mol
fraction value for the multiple equilibria existing between the
receptor and anions, which equaled a 1:1 complex in CH3CN.
The receptor 1 showed strong electrochemical responses for
F- ion with a remarkable phenomenon of two pairs of
reduction peaks merging into one with the increment of
1
workers.18 According to the H, 19F and 11B NMR titration
spectra the proposed mechanism of receptor 1 towards F- ion
on electrochemical measurements was further confirmed, in
which there was a formation of borate-ester and free F- ion
and
hydrogen
bonding
with
the
F-
ion.
1
anions. H titration experiments demonstrated that receptor 1
displayed high selectivity for F- ion over other anions and
-
binded with anions in the order F- > AcO- > Cl- > Br- > HSO4 ,
which was consistent with the basicity order of these anions.
19F and 11B titration experiments proved the existence of the
interaction between receptor 1 and fluoride ions. Further
Figure 8. 19F NMR spectra of receptor 1 (c = 5×10-3 M) in
DMSO-d6 upon the addition of various concentrations of F-
ion.
investigations
on
ferrocenyl-substituted
boronate
chemosensors and towards enhancing their selectivity and
sensitivity are currently ongoing in our laboratory.
Acknowledgments
We are grateful for the financial support from the National
Natural Science Foundation of China (No. 21202019 and
21372043 ) and the Research Fund for the State Key
Laboratory of Structural Chemistry, Fujian Institute of
Research on the Structure of Matter, Chinese Academy of
Sciences (No. 20120010)
Figure 9. 11B NMR spectra of receptor 1 (c = 0.04 M) in
DMSO-d6 upon the addition of various concentrations of F-
ion.
Supplementary data
Supplementary data associated (general experimental
section, characterization of receptor 1 and additional
In summary, we have synthesized 2,2-diferrocenylpropane
benzimidazolium borate-ester receptor 1 and examined the

8
Tetrahedron
Y.-B. Chem. Soc. Rev. 2013, 42, 8032-8048; (i) Guo, Z.; Shin, I.;
Yoon, J. Chem. Commun. 2012, 48, 5956-5967.
spectroscopic data) with this article can be found, in the
8. (a) Li, B.; Zhang, C.; Liu, C.; Chen, J.; Wang, X.; Liu, Z.; Yi, F.
RSC Adv. 2014, 4, 46016-46019; (b) Mahapatra, A. K.; Manna, S.
K.; Pramanik, B.; Maiti, K.; Mondal, S.; Ali, S. S.; Mandal, D.
RSC Adv. 2015, 5, 10716-10722; (c) Zhou, X.; Lai, R.; Li, H.;
Stains, C. I. Anal. Chem. 2015, 87, 4081-4086; (d) Yu, Y.; Dong,
C. Anal. Chem. 2015, 7, 9604-9608; (e) Liu, Y.; Wang, S. Q.;
Zhao, B. X. Rsc Adv. 2015, 5, 32962-32966; (f) Li, B.; Zhang, C.;
Wang, Y.; Liu, C.; Chen, J.; Zhou, T.; Yi, F. Luminescence 2015,
30, 699-702; (g) Yeh, J.-T.; Venkatesan, P.; Wu, S.-P. New J.
Chem. 2014, 38, 6198-6204.
9. Xu, S. Y.; Sun, X.; Ge, H.; Arrowsmith, R. L.; Fossey, J. S.; Pascu,
S. I.; Jiang, Y. B.; James, T. D. Org. Biomol. Chem. 2015, 13,
4143-4148.
10. Umasekhar, B.; Ganapathi, E.; Chatterjee, T.; Ravikanth, M.
Dalton Trans. 2015, 44, 16516-16527.
11. (a) Zhou, L.; Fan, X.-T.; Xu, Y.-D.; Cao, Q.-Y. New J. Chem.
2015, 39, 8087-8092; (b) Sun, R. L.; Wang, L.; Yu, H. J.; Zain-ul-
Abdin; Chen, Y. S.; Huang, J.; Tong, R. B. Organometallics 2014,
33, 4560-4573; (c) Cao, Q.-Y.; Han, Y.-M.; Yao, P.-S.; Fu, W.-F.;
Xie, Y.; Liu, J.-H. Tetrahedron Lett. 2014, 55, 248-251; (d)
Thakur, A.; Mandal, D.; Ghosh, S. J. Organomet. Chem. 2013,
726, 71-78; (e) Alfonso, M.; Espinosa, A.; Tarraga, A.; Molina, P.
Chem. Commun. 2012, 48, 6848-6850.
12. (a) Wan, Q.; Zhuo, J.-B.; Wang, X.-X.; Lin, C.-X.; Yuan, Y.-F.
Dalton Trans. 2015, 44, 5790-5796; (b) Su, Z.-M.; Ye, H.-M.;
Zhu, X.-X.; Xie, L.-L.; Bai, S.; Yuan, Y.-F. J. Organomet. Chem.
2014, 750, 162-168.
13. (a) Li, A.-F.; Wang, J.-H.; Wang, F.; Jiang, Y.-B. Chem. Soc. Rev.
2010, 39, 3729-3745; (b) Zhang, Y.; Li, C.; Li, J.; Wang, T.;
Zhang, H.; Yu, X. J. Organomet. Chem. 2015, 783, 116-119; (c)
Mulas, A.; Willener, Y.; Carr-Smith, J.; Joly, K. M.; Male, L.;
Moody, C. J.; Horswell, S. L.; Nguyen, H. V.; Tucker, J. H. R.
Dalton Trans. 2015, 44, 7268-7275; (d) Alfonso, M.; Espinosa
Ferao, A.; Tárraga, A.; Molina, P. Inorg. Chem. 2015, 54, 7461-
7473; (e) Cao, Q.-Y.; Pradhan, T.; Lee, M. H.; No, K.; Kim, J. S.
Analyst 2012, 137, 4454-4457; (f) Molina, P.; Tárraga, A.;
Caballero, A. Eur. J. Inorg. Chem. 2008, 2008, 3401-3417; (g)
Ge, J.-Z.; Zou, Y.; Yan, Y.-H.; Lin, S.; Zhao, X.-F.; Cao, Q.-Y. J.
Photoch. Photobio. A 2016, 315, 67-75.
14. (a) Li, M.; Guo, Z.; Zhu, W.; Marken, F.; James, T. D. Chem.
Commun. 2015, 51, 1293-6; (b) Dechtrirat, D.; Gajovic-
Eichelmann, N.; Wojcik, F.; Hartmann, L.; Bier, F. F.; Scheller, F.
W. Biosens. Bioelectron. 2014, 58, 1-8; (c) Thakur, A.; Mandal,
D.; Sao, S.; Ghosh, S. J. Organomet. Chem. 2012, 715, 129-135;
(d) Mirri, G.; Bull, S. D.; Horton, P. N.; James, T. D.; Male, L.;
Tucker, J. H. R. J Am. Chem. Soc. 2010, 132, 8903-8905.
15. (a) Suresh, P.; Pitchumani, K. J. Org. Chem. 2008, 73, 9121-9124;
(b) Yang, Q.; Wang, Y.; Zhang, B.; Zhang, M. Chinese J. Chem.
2012, 30, 2389-2393.
online version, at
References and notes
1. (a) Gale, P. A.; Caltagirone, C. Chem. Soc. Rev. 2015, 44, 4212-
4227; (b) Rezanka, M.; Langton, M. J.; Beer, P. D. Chem.
Commun.2015, 51, 4499-4502; (c) Mercurio, J. M.; Caballero, A.;
Cookson, J.; Beer, P. D. RSC Adv. 2015, 5, 9298-9306; (d) Zapata,
F.; Caballero, A.; Molina, P.; Alkorta, I.; Elguero, J. J. Org.
Chem. 2014, 79, 6959-6969; (e) Gale, P. A.; Busschaert, N.;
Haynes, C. J. E.; Karagiannidis, L. E.; Kirby, I. L. Chem. Soc.
Rev. 2014, 43, 205-241; (f) Xu, W.; Zhou, Y.; Huang, D.; Su, M.;
Wang, K.; Xiang, M.; Hong, M. J. Mater. Chem. C 2015, 3, 2003-
2015; (g) Lee, M.; Jo, S.; Lee, D.; Xu, Z.; Yoon, J. Dyes Pigments
2015, 120, 288-292; (h) Cao, Q.-Y.; Li, M.; Zhou, L.; Wang, Z.-
W. RSC Adv. 2014, 4, 4041-4046.
2. (a) Ke, B.; Wu, W.; Wei, L.; Wu, F.; Chen, G.; He, G.; Li, M.
Anal. chem. 2015, 87, 9110-9113; (b) Akula, M.; Thigulla, Y.;
Nag, A.; Bhattacharya, RSC Adv. 2015, 5, 57231-57234; (c)
Zhang, D.; Yang, H.; Martinez, A.; Jamieson, K.; Dutasta, J. P.;
Gao, G. Chemistry 2014, 20, 17161-17167; (d) Roy, A.; Kand, D.;
Saha, T.; Talukdar, P. Chem. Commun. 2014, 50, 5510-5513; (e)
Hu, B.; Lu, P.; Wang, Y. Sens. Actuators B 2014, 195, 320-323.
3. (a) Zou, L.; Yan, B.; Pan, D.; Tan, Z.; Bao, X. Spectrochimica
Acta A 2015, 148, 78-84; (b) Yang, X.; Zhang, G.; Li, Y.; Liu, Z.;
Gong, X.; Gao, B.; Zhang, G.; Cui, Y.; Sun, G. RSC Adv. 2015, 5,
22455-22462; (c) Yan, G.; Li, H.; Zhu, Y. R.; Shi, B.; Qu, W.; Lin,
Q.; Yao, H.; Zhang, Y.; Wei, T. New J. Chem. 2015, 39, 8797-
8801; (d) Parthiban, C.; Elango, K. P. Sens. Actuators B 2015, 215,
544-552; (e) Mahapatra, A. K.; Karmakar, P.; Roy, J.; Manna, S.;
Maiti, K.; Sahoo, P.; Mandal, D. RSC Adv. 2015, 5, 37935-37942.
4. (a) Cametti, M.; Rissanen, K. Chem. Soc. Rev. 2013, 42, 2016-38;
(b) Zhou, Y.; Zhang, J. F.; Yoon, J. Chem. Rev. 2014, 114, 5511-
71; (c) Wade, C. R.; Broomsgrove, A. E. J.; Aldridge, S.; Gabbaï,
F. P. Chem. Rev. 2010, 110, 3958-3984.
5. (a) Zapata, F.; Sabater, P.; Caballero, A.; Molina, P. Org. Biomol.
Chem. 2015, 13, 1339-1346; (b) Jun, E. J.; Xu, Z.; Lee, M.; Yoon,
J. Tetrahedron Lett. 2013, 54, 2755-2758; (c) Xu, Z.; Kim, S. K.;
Han, S. J.; Lee, C.; Kociok-Kohn, G.; James, T. D.; Yoon, J. Eur.
J. Org. Chem. 2009, 2009, 3058-3065; (d) Caballero, A.; White, N.
G.; Beer, P. D. CrystEngComm 2014, 16, 3694-3698; (e)
Gonzalez-Mendoza, L.; Altava, B.; Burguete, M. I.; Escorihuela,
J.; Hernando, E.; Luis, S. V.; Quesada, R.; Vicent, C. RSC Adv.
2015, 5, 34415-34423; (f) Zhang, D.; Jiang, X.; Dong, Z.; Yang,
H.; Martinez, A.; Gao, G. Tetrahedron 2013, 69, 10457-10462; (g)
Swatloski, R. P.; Holbrey, J. D.; Rogers, R. D. Green Chem. 2003,
5, 361-363; (h) Zhu, Z. -Q.; Jiang, M. -Y.; Zheng, C. –G.; Xiao, J.
–C. J. Fluorine. Chem. 2012, 133, 160-162.
6. (a) Yousuf, M.; Ahmed, N.; Shirinfar, B.; Miriyala, V. M.; Youn,
I. S.; Kim, K. S. Org. Lett. 2014, 16, 2150-2153; (b) Zhuo, J. B.;
Lin, C. X.; Wan, Q.; Xie, L. L.; Yuan, Y. F. J. Organomet. Chem.
2015, 791, 289-297; (c) Zhuo, J.-B.; Zhu, X.-X.; Lin, C.-X.; Bai,
S.; Xie, L. -L.; Yuan, Y. -F. J. Organomet. Chem. 2014, 770, 85-
93; (d) Kong, D.; Weng, T.; He, W.; Liu, B.; Jin, S.; Hao, X.; Liu,
S. J. Organomet. Chem. 2013, 727, 19-27; (e) Niu, H. T.; Yin, Z.
M.; Su, D. D.; Niu, D.; He, J. Q.; Cheng, J. P. Dalton Trans. 2008,
28, 3694-700; (f) Bai, Y.; Zhang, B.-G.; Duan, C.-Y.; Dang, D.-B.;
Meng, Q.-J. New J. Chem. 2006, 30, 266-271; (g) Jiang, X.; Feng,
M.; Zhang, D.; Wang, B.; Dong, Z.; Gao, G. Chinese J. Chem.
2013, 31, 673-678; (h) Yoon, J.; Kim, S. K.; Singh, N. J.; Kim, K.
S. Chem. Soc. Rev. 2006, 35, 355-360.
16. (a) Niu, H.-T.; Yin, Z.; Su, D.; Niu, D.; Ao, Y.; He, J.; Cheng, J.-P.
Tetrahedron 2008, 64, 6300-6306; (b) Zhuo, J. B.; Zhang, C. Y.;
Lin, C. X.; Bai, S.; Xie, L. L.; Yuan, Y. F. J. Organomet. Chem.
2014, 763, 34-43; (c) Molina, P.; Tarraga, A.; Alfonso, M. Dalton
Trans. 2014, 43, 18-29; (d) Romero, T.; Orenes, R. A.; Tárraga,
A.; Molina, P. Organometallics 2013, 32, 5740-5753; (e) Molina,
P.; Tarraga, A.; Alfonso, M. Dalton Trans. 2013, 43, 18-29; (f)
Alfonso, M.; Tarraga, A.; Molina, P. Inorg. Chem. 2013, 52,
7487-96; (g) Cao, Q.-Y.; Pradhan, T.; Lee, M. H.; Choi, D. H.;
Kim, J. S. Tetrahedron Lett. 2012, 53, 4917-4920.
17. Kumar, R.; Guchhait, T.; Mani, G. Inorg. Chem. 2012, 51, 9029-
9038.
18. Hu, P.; Song, Y.; Rojas−Andrade, M. D.; Chen, S. Langmuir 2014,
30, 5224-5229.
7. (a) Lin, W.; Tan, Q.; Liang, H.; Zhang, K. Y.; Liu, S.; Jiang, R.;
Hu, R.; Xu, W.; Zhao, Q.; Huang, W. J. Mater. Chem. C 2015, 3,
1883-1887; (b) Sharma, R.; Gautam, P.; Misra, R.; Shukla, S. K.
RSC Adv. 2015, 5, 27069-27074; (c) Misra, R.; Jadhav, T.;
Dhokale, B.; Mobin, S. M. Dalton Trans. 2015, 44, 16052-16060;
(d) Wu, X.; Chen, X.-X.; Song, B.-N.; Huang, Y.-J.; Ouyang, W.-
J.; Li, Z.; James, T. D.; Jiang, Y.-B. Chem. Commun. 2014, 50,
13987-13989; (e) Swamy P, C. A.; Mukherjee, S.; Thilagar, P.
Inorg. Chem. 2014, 53, 4813-4823; (f) Madhu, S.; Ravikanth, M.
Inorg. Chem. 2014, 53, 1646-1653; (g) Hu, Y.; Zhao, Z.; Bai, X.;
Yuan, X.; Zhang, X.; Masuda, T. RSC Adv. 2014, 4, 55179-55186;
(h) Wu, X.; Li, Z.; Chen, X.-X.; Fossey, J. S.; James, T. D.; Jiang,

2
Tetrahedron
Graphical Abstract
Leave this area blank for abstract info.
Highly Selective Detection of Fluoride Based on
2,2-Diferrocenylpropane Benzimidazolium Borate-ester Salt
Zhi-Ming Su, Xi-Quan Yan, Chao-Li Liang, Cai-Xia Lin,
Li-Li Xie, Yao-Feng Yuan*
1