Ferrocenyl-sulfonium ionic liquids-synthesis, characterization and electrochemistry

Article abstract of DOI:10.1039/c7dt04139j

New ferrocenylsulfonium cation based ionic liquids were prepared by direct alkylation of the corresponding ferrocenyl-based thioethers with N-alkylbis(trifluoromethanesulfonyl)imides (R′TFSI). This convenient direct access to organometallic sulfonium bis(trifluoromethanesulfonyl)imide (TFSI) salts without the need for ion exchange was chosen in order to obtain highly pure and reversibly redox active room temperature ILs in many cases. In other cases the anion cation interaction in the solid state was studied by XRD analyses. Moreover a diferrocenylmethylsulfonium tetrafluoroborate with two redox active centers was synthesized. The redox chemistry of these sulfonium salts was investigated via cyclic voltammetry. Furthermore, UV-Vis spectra and thermoanalytical data are discussed. The electron-withdrawing sulfonium group is directly bonded to the ferrocenyl unit, therefore this cationic group influences the potential of these ionic liquids in a more pronounced way than being anchored to the ferrocenyl unit via an organic spacer. With their low absorbance in the visible light and reversible, tunable redox potential, these room temperature ILs open perspectives as redox mediators in dye sensitized solar cells (DSSCs), as redox electrolytes in supercapacitors or as overcharge protection additives in batteries.

Full text of DOI:10.1039/c7dt04139j

View Article Online
View Journal
Dalton
Transactions
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: A. Venker, T.
Vollgraff and J. Sundermeyer, Dalton Trans., 2017, DOI: 10.1039/C7DT04139J.
Volume 45 Number
1
7
January 2016 Pages 1–398
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Dalton
Transactions
An international journal of inorganic chemistry
www.rsc.org/dalton
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1477-9226
PAPER
Joseph T. Hupp, Omar K. Farha et al.
Efficient extraction of sulfate from water using
framework
a Zr-metal–organic
rsc.li/dalton

Page 1 of 10
Plea sDe a dl t oo nn oT tr aa nd sj ua cs tt i om nasrgins
View Article Online
DOI: 10.1039/C7DT04139J
Journal Name
ARTICLE
Ferrocenyl-Sulfonium Ionic Liquids - Synthesis, Characterization
and Electrochemistry
Received 00th January 20xx,
Accepted 00th January 20xx
a
a
a
Alexander Venker, Tobias Vollgraff, Jörg Sundermeyer*
DOI: 10.1039/x0xx00000x
New ferrocenylsulfonium cation based ionic liquids were prepared by direct alkylation of corresponding ferrocenyl-based
thioethers with N-alkylbis(trifluoromethanesulfonyl)imides (R’TFSI). This convenient direct access to organometallic
sulfonium bis(trifluoromethanesulfonyl)imide (TFSI) salts without need for ion exchange was chosen in order to get highly
pure and reversibly redox active room temperature ILs in many cases. In other cases anion cation interaction in the solid
state was studied by XRD analyses. Moreover a diferrocenylmethylsulfonium tetrafluoroborate with two redoxactive
centers was synthesized. The redoxchemistry of these sulfonium salts was investigated via cyclic voltammetry.
Furthermore, UV-Vis spectra and thermoanalytical data are discussed. The electron-withdrawing sulfonium group is
directly bonded to the ferrocenyl unit, therefore this cationic group influences the potential of these ionic liquids in a more
pronounced way than being anchored to the ferrocenyl unit via an organic spacer. With their low absorbance in the visible
light and reversible, tunable redox potential, these room temperature ILs open perspectives as redox mediators in dye
sensetized solar cells (DSSCs), as redox electrolytes in supercapacitors or as overcharge protection additives in batteries.
www.rsc.org/
Introduction
Fundamental and application oriented studies on ferrocene
based ILs include mass transport and electrochemical
1
2,13
properties
as well as the modification of platinum
1
In recent years a number of ferrocene-based ionic liquids were
reported. The synthetically most simple way to combine the
robust, fully reversible organometallic redox group, ferrocene,
with the functionality of an ionic liquid or salt is to anchor the
4
electrode surfaces. Furthermore ferrocene based ionic
liquids were tested for their application as redox active species
1
3,15
in electrolytes for lithium ion batteries
6
or as redox-active
1
1
,2
electrolyte supercapacitors. Recently, a ferrocene viologen
linked ionic liquid was published as an electrochromic
ferrocenyl substituent via an organic linker to an anion or
3
–10
more often to a cation.
4,10
Spacer-free ionic liquids where the
1
7
1
anion or cation
1
material which could be interesting for its application in
optical sensors or electronic displays. Free ferrocenium ion
based ionic liquids were prepared due to their interesting
is directly bonded to the ferrocenyl redox
unit are much less investigated. Recently we reported a
4
number of such ferrocenylphosphonium ILs. Their potential
1
8
magnetic properties.
could be tuned in a broad range due to direct influence of
differently substituted electron withdrawing phosphonium
While trialkylsulfonium dicyanamides, bis(fluorosulfonyl)imides and
TFSI salts are described as ionic liquids with low melting points and
2
substituents [FcPR’R ]TFSI to the redox center. In this context,
19–21
low viscosity,
ferrocenyl substituted sulfonium ILs have not yet
we became interested in corresponding ferrocenylsulfonium
ILs [FcSR’R]TFSI. In contrast to literature known ferrocenyl-
based ionic liquids, these ILs do not contain linker groups such
as keto or ester functionalities between the ionic tag and the
ferrocenyl group, which are not stable under very reductive
conditions or alkyl spacers which are prone to be oxidized and
been thoroughly investigated with respect to their thermal and
electrochemical ILs properties. Early reports of Knox et al. describe
ferrocenyldimethylsulfonium iodide, which is only stable in solid
state. Attempts to recrystallize this salt lead to dealkylation of the
2
2
cation. The critical role of nucleophilic iodide was recognized and
a thermally more stable ferrocenyldimethylsulfonium salt involving
+
cleaved with loss of stabilized cation [FcCHR] .
2
3
a methyl sulfate counter anion was published later. Finally, a
ferrocene with two dimethylsulfonium substituents, one at each
ring, has been described as tetrachloroferrate(II) salt, however, it
2
4
could not be recrystallized due to its instability in solution. Its
synthesis involved the reaction of dimethylsulfonium
cyclopentadienylide with FeCl
sulfonium salts generates S-ylides that were used for
stereoselective syntheses of epoxides from carbonyl
2
. Deprotonation of such ferrocenyl
2
5,26
compounds.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 2 of 10
View Article Online
DOI: 10.1039/C7DT04139J
ARTICLE
Journal Name
alkylbis(trifluoromethanesulfonyl)imide R’TFSI at 90-120 °C
Scheme 1). After decoloration with charcoal in acetonitrile,
(
the products can be isolated by evaporation of all volatiles at
high vacuum. Compounds 1a, b, d were obtained as orange to
brown-yellow oils, while 1c crystallized at rt after a certain
time. Compounds 2a and
b were received as yellow to red-
brown solids. For compounds with three different substituents
at the sulfur atom, the racemic mixture was obtained.
Butylation of ferrocenyl methyl sulfide surprisingly yielded a
product mixture of dimethylsulfonium derivative 1a, expected
n-butylmethylsulfonium derivative 1b and di-n-butylsulfonium
compound 1c. That means, product 1b acted as methyl
transfer reagent towards ferrocenyl methyl sulfide starting
material. 1a was also a side product in the synthesis of 1d by
Scheme 1. Alkylation of ferrocenyl thioethers with N-methyl- and N-n-
butylbis(trifluoromethansulfonyl)imide. For 1: R‘ = Me, R = Me (a), n-Bu (b), Ph (c), Fc
1
reaction of Fc-S-Fc with Me-TFSI. According to H NMR
(
d); R‘ = n-Bu, R = n-Bu (e), Ph (f). For 2: R‘ = Me, R = Me (a), n-Bu (b).
spectroscopy 1d is contaminated by 2-3% of 1a. Therefore, the
−
high purity BF4 analogue of 1d, complex
3 was prepared by
Herein we present the preparation of comparatively stable
ferrocenylsulfonium based ionic liquids containing S-alkyl and S-
methylation of Fc-S-Fc by more reactive trimethyloxonium
tetrafluoroborate Meerwein salt in dichloromethane
phenyl substituents and
accomplished by simple alkylation of mono- and bisferrocenyl
substituted sulfides with N-alkylbis(trifluoromethane-
a TFSI anion. Their synthesis is
(Scheme 2). 3 was crystallized in form of orange needles
containing one equivalent of acetonitrile.
sulfonyl)imides. Their redox potentials, absorption spectra and
thermal stabilities are discussed.
13C NMR 1c
Cp'
'
'
Me
S+
Ph
Results and discussion
Fe
Preparation of Redoxactive Sulfonium Ionic Liquids.
Cp'
Due of the instability of the ferrocenyldimethylsulfonium
2
2
iodide, we followed a synthetic strategy avoiding any anion
exchange and any electrochemically active water or halide
impurities in the IL product. The advantage of using N-methyl-
and N-n-butylbis(tifluoromethanesulfonyl)imide as alkylating
agent has been laid out by our recent report on
ferrocenylphosphonium ILs with non-nucleophilic TFSI counter
'
'
CS
4
ions.
13C NMR 2b
The alkyl ferrocenyl sulfides were prepared via a slightly
2
5
'
'
CH2
modified procedure originally described by Minière et al..
A
'
Bu
S+
Me
monolithoferrocene solution obtained by lithiation of
'
Fe
ferrocene with tert-butyllithium and potassium tert-butanolate
2
78 °C in THF was treated with dimethyl disulfide. After
7
at
−
CS
Me S+
Bu
separation of ionic thiolates, ferrocenyl methyl sulfide can be
isolated by distillation in yields up to 77% at higher reaction
scales. The preparation of di(butylthio)ferrocene was carried
out by the reaction of dilithioferrocene ∙ TMEDA and dibutyl
disulfide.
The subsequent alkylation of the precursor molecules was
performed without any solvent applying an excess of
1
3
Figure 1. C NMR (75.5 MHz, CD
3
CN) spectra of ferrocenylmethylphenylsulfonium
TFSI 1c (top); α- and β-carbon signals split in the NMR spectra because of different
1
3
3
substituents bonded to the sulfur atom. C NMR (75.5 MHz, CD CN) spectra of 1,1’-
Scheme 2. Methylation of diferrocenyl sulfide with trimethyloxonium
bis(butylmethylsulfonium)ferrocene 2 TFSI 2b (bottom); two pairs of stereoisomers,
the R,R and S,S pair of enantiomers as well as the R,S meso compounds are formed.
tetrafluoroborate in dichloromethane.
2
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 3 of 10
Plea sDe a dl t oo nn oT tr aa nd sj ua cs tt i om nasrgins
View Article Online
DOI: 10.1039/C7DT04139J
Journal Name
ARTICLE
UV-Vis Spectra of Ferrocenyl-Sulfonium Ionic Liquids.
For the application as redox mediator in DSSCs, ionic liquids
should show low absorbance of the terrestrial solar radiation -
in contrast to the iodide/triiodide redox couple, they should
not compete with the desired absorption of the dye. In order
to evaluate their absorptivity UV-Vis spectra of the prepared
compounds 1a, b, c, e, f, 2a, b and
3
were recorded in
in the
acetonitrile. Representative spectra of 1a, c, 2a and
3
range of 280 nm to 900 nm are shown in Figure 2. All
compounds reveal a rather weak absorption at about 435 nm,
which is responsible for their pale yellow solutions. Values for
the absorption maximum for the local maximum and the
corresponding molar absorption coefficient are listed in
Table 1. The extinction coefficients of dialkyl substituted
−
1
−
1
sulfonium ions are about 180 L mol cm . Compared to
Figure 2. UV-Vis spectra of compounds 1a, 1c, 2a and
3 in acetonitrile
ferrocene (ε = 87 L mol− cm− in ethanol at 440 nm) , the
absorption of the local maximum is higher, but weaker
compared to ferrocenylmethyldiphenylphosphonium TFSI
1
1
29
c ≈ 0.5 mmol L−1) at room temperature between 280 nm and 900 nm.
(
NMR Spectroscopy.
ε = 241 L mol cm− in dichloromethane at 447 nm). Phenyl
−
1
1
4
(
As anticipated alkylation of ferrocenyl sulfides leads to a down substituted and dicationic ferrocenylsulfonium ionic liquids
1
13
field shift of H and C signals in comparison to ferrocenyl have higher molar absorption coefficients of about
−
1
−
1
thioether starting materials. An electron withdrawing ε = 305 L mol cm .
sulfonium group is formed, their positive charge leads to a tetrafluoroborate
Bisferrocenylmethylsulfonium
3
shows the highest absorption coefficient
1
deshielding effect similar to corresponding phosphonium with ε = 549(4) L mol cm−
−
1
caused by the second
salts. Similar trends of downfield shifts have been observed chromophoric ferrocene unit. All investigated compounds have
4
2
8
for ferrocenyl phenyl sulfide, -sulfoxide and -sulfone.
Ionic liquids with three different substituents at pyramidal and lower wavelengths. Compound 1c shows a second
high extinction coefficients in the range of 360 nm to 280 nm
−
1
−
1
sulfur reveal a center of chirality. As a consequence a maximum absorption at 303 nm (ε = 1412(20) L mol cm ).
characteristic splitting of the Cp and Cp signals is observed in For compounds 1f and
these absorbance maxima are
H and C NMR spectra. The C NMR spectrum of 1c is shown indicated by shoulders. All prepared ionic compounds show
in Figure 1.
much lower absorbance compared to the well-established
For 1,1’-bis(butylmethylsulfonium)ferrocene 2b two pairs of 3I /I redox system, which is often used for DSSC. For
α
β
3
1
13
13
−
−
3
diastereomers can be detected via NMR spectroscopy in an [Me N]I3
a
molar
absorption
coefficient
of
4
about 1:1 ratio. One set of signals belong to the R,R and S,S ε = 25500 L mol cm− at 360 nm in acetonitrile was
−
1
1
3
0
enantiomers. The other set is caused by the R,S meso determined.
compounds (Figure 1, bottom).
Table 2. Phase transitions, decomposition temperatures and equilibrium
potentials of ferrocenylsulfonium compounds. Melting temperatures (T ) were
detected optical or via differential scanning calorimetry (DSC, heating rate:
m
a
b
-
1
1
0 K min , values given as onset temperature). Decomposition temperatures (T
d
)
were measured via thermogravimetric analysis (TGA) and determined as 3%
Table 1. Wavelength of maximal absorption of new ionic ferrocenylsulfonium
ionic liquids and the corresponding molar absorption coefficient, measured in
acetonitrile.
2+
3+
weight loss. Half-wave potentials (E1/2, Fe /Fe ) were recorded in [EMIM]TFSI at
-1
1
0 mV s against ferrocene/ferrocenium with an Ag/AgTFSI reference electrode.
c
-1
measured at 50 mV s because of better peak separation.
Compound
Wavelength of
molar absorption
coefficient
Compound
T
m
(T
g
) / °C
T
d
/ °C
E
1/2 / mV vs.
maximal absorption
+
Fc/Fc
/l mol− cm
1
−1
/
nm
b
[
[
[
[
[
[
[
[
FcSMe ]TFSI 1a
2
(−44.6)
237
530
531
[
[
[
[
[
[
[
[
FcSMe ]TFSI 1a
2
431
435
437
435
434
439
424
439
177(2)
FcSBuMe]TFSI 1b
FcSMePh]TFSI 1c
FcSBuMe]TFSI 1b
FcSMePh]TFSI 1c
175(4)
a
55.1
548
303(1)
FcSBu
FcSBuPh]TFSI 1f
Fc(SMe ]TFSI 2a
Fc(SBuMe)
Fc SMe]BF
2
]TFSI 1e
525
FcSBu
FcSBuPh]TFSI 1f
Fc(SMe ]TFSI 2a
Fc(SBuMe)
Fc SMe]BF
2
]TFSI 1e
191(6)
538
305(5)
a
2
)
2
2
83.7
206
215
234
1001
1005
2
)
2
2
305(44)
319(5)
b
2
]TFSI
2
2b
93.0
2
]TFSI
2
2b
a
c
2
4
3
130.7
499
3
549(4)
c
2
4
6
67
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 4 of 10
View Article Online
DOI: 10.1039/C7DT04139J
ARTICLE
Journal Name
Figure 4. Molecular structure of 4, hydrogen atoms omitted for clarity. Relevant bond
distances per Å and angels per °: S1-C1: 1.754(2), S1-C11: 1.793(3), S1-C12: 1.796(2),
C1-C2: 1.433(3), C2-C3: 1.413(3), C3-C4: 1.427(3), C4-C5, 1.413(3), C1-C5: 1.435(3), S1-
2
C1-C2: 122.96(16), S1-C1-C5: 128.16(15), Fe1-Cp(SMe ): 1.6642(3), Fe1-Cp’: 1.6558(3).
ILs is shifted by 56 mV to higher potentials, e.g. for
FcSMe ]TFSI 1a in comparison to [FcPMe ]TFSI and 18 mV for
]TFSI 2a in comparison to [Fc(PMePh ]TFSI
despite of the phenyl substituents, respectively.
For diferrocenylmethylsulfonium BF 3 a second redox
[
2
3
Figure 3. Cyclic voltammetry scans of selected new ferrocenylsulfonium compounds
+
plotted against Fc/Fc . The measurements were performed in [EMIM]TFSI with an [Fc(SMe
2
)
2
2
2
)
2
2
,
−
1
4
Ag/AgTFSI reference electrode with a scan rate of 10 mV s for compounds 1a, 1c, 2b.
In case of compound 3 a scan rate of 50 mV s− was chosen because of better peak
separation.
1
4
potential could be measured. The first one was detected at a
lower potential compared to the other investigated sulfonium
ionic liquids (499 mV), while the second one falls into the
range of the mono- and the disubstituted ferrocenes (667 mV).
Thermal Analysis of Ferrocenyl-Sulfonium Ionic Liquids.
The solid compounds 1c, 2a, 2b and 3 as well as the oil 1a were
For [FcSMe
the neat IL. No decomposition of 1a was noticed up to a
reduction potential of 2.0 V versus ferrocene/ferrocenium.
2
]TFSI 1a the reductive stability was investigated in
investigated regarding their melting and decomposition
temperatures (Tm and T , respectively). Measured
d
−
temperatures are listed in Table 2. All ionic compounds are
stable up to temperatures of about 200 °C. The dicationic salts
However, we observed, that some ferrocenylsulfonium
compounds start to decompose to some extent while standing
after CV measurement in the electrochemical cell over several
hours. This decomposition was not observed in glass tubes and
is probably induced by the large platinum surface of the
bis(dimethylsulfonium)ferrocene
2a
and
bis(butylmethylsulfonium)ferrocene 2b reveal higher melting
points of 83.7 and 93.0 °C, nevertheless they can be regarded
as ionic liquids with unusually low lattice energy. Only for
1
000
ꢀL microcell crucible and electrode.
diferrocenylmethylsulfonium tetrafluoroborate
3 a melting
point of 130.7 °C, higher than the formal 100 °C limit for ILs, is
Crystal Structures of Ferrocenyl-Sulfonium Salts.
observed. The TFSI salts 1a, 1b, 1e and 1f are obtained as oils.
For 1a as a representative example, differential scanning For the first time it was possible to investigate two
calorimetry was performed, but no melting point could be ferrocenylsulfonium compounds by X-ray crystallography.
observed due to the formation of a supercooled glass.
Crystals suitable for XRD of ferrocenyldimethylsulfonium
iodide were obtained by the reaction of ferrocenyl methyl
sulfide with an excess of neat iodomethane by slow cooling.
The molecular structure is depicted in Figure 4.
Cyclic Voltammetry of Ferrocenyl-Sulfonium Salts.
It is known, that electron withdrawing substituents cause a
II
III
31
Ferrocenyldimethylsulfonium iodide
4 crystallizes in the space
3
positive shift of the Fe /Fe ferrocene redox potential. This
behavior was also observed for the prepared ferrocene-based
ionic liquids. In dependence of the ferrocene substituents,
equilibrium potential of the compounds is shifted (Table 2,
Figure 3).
2
group P2 /c with four molecules per unit cell.
1
The
bis(dimethylsulfonium)ferrocen cation was crystallized after an
exchange of the TFSI anion by sodium tetraphenylborate from
an acetonitrile/THF/diethyl ether mixture. The resulting
bis(dimethylsulfonium)ferrocene
ditetraphenylborate 5
The positive charge of the sulfonium group leads to a half-
ꢀ
crystallizes in the triclinic space group P1 with one equivalent
2
wave potential for [FcSMe ]TFSI 1a of 530 mV versus
3
3
THF (Figure 5). In both compounds a nearly eclipsed
conformation of the Cp rings is found: The deviation from ideal
ferrocene/ferrocenium redox couple in electrochemically
innocent 1-ethyl-3-methylimidazolium ([EMIM]) TFSI as
solvent. Longer alkyl chains do not show a strong influence on
the potential while a phenyl group leads to an additional shift
of 18 mV for ferrocenylmethylphenylsulfonium TFSI 1c. The
incorporation of an additional sulfonium group affects an
almost doubled raise of the potential up to 1.001 V for
bis(dimethylsulfonium)ferrocene 2a in comparison to the
unsubstituted ferrocene. Compared to corresponding
ferrocenylphosphonium ILs, the redox potential of sulfonium
conformation is 0.7° for monocationic
dicationic
The sulfur atom of
4 and 10.8° for
5
.
4
reveals a pyramidal configuration. It is
surrounded by one ferrocenyl unit and two methyl groups. In
first approximation the non-bonding S-electron pair is coplanar
to the cyclopentadienyl plain. For C1-S1 a distance of
1
.754(2) Å is observed, whereas S1-C11 and S1-C12 are
.793(3) Å and 1.796(2) Å, respectively. As expected, the S1-
1
4
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 5 of 10
Plea sDe a dl t oo nn oT tr aa nd sj ua cs tt i om nasrgins
View Article Online
DOI: 10.1039/C7DT04139J
Journal Name
ARTICLE
stabilities compared to state of the art ferrocenylsulfonium
salts, this class of room temperature ionic liquids might be
useful as redox mediators for DSSCs, as redox electrolytes in
supercapacitors or as overcharge protection additives in
batteries. In contrast to literature known ferrocenyl-based
ionic liquids, the ILs described here do not contain linker
groups such as keto or ester functionalities between the ionic
tag and the ferrocenyl group, which are not stable under very
reductive conditions or alkyl spacers, which are prone to be
+
oxidized and cleaved with loss of stabilized cation [FcCHR] .
Conflicts of interest
Figure 5. Molecular structure of 5∙THF, hydrogen atoms omitted for clarity. Relevant
There are no conflicts to declare.
bond distances per Å and angels per °: S1-C1: 1.749(2), S1-C11: 1.790(2), S1-C12:
1
1
1
.797(2), C1-C2: 1.433(3), C2-C3: 1.415(2), C3-C4: 1.422(3), C4-C5, 1.424(3), C1-C5:
.431(2), S2-C6: 1.756(2), S2-C13: 1.788(2), S2-C14: 1.794(3); C6-C7: 1.436(3), C7-C8:
.421(2), C8-C9: 1.425(3), C9-C10: 1.414(2), C10-C6: 1.426(3), S1-C1-C2: 122.02(11), S1-
Acknowledgements
C1-C5: 128.49(11), S2-C6-C7: 122.64(12), S2-C6-C10: 128.01(11), Fe-Cp: 1.6522(3),
1
.6504(3).
We thank the Hessisches Graduiertenprogramm für wissen-
schaftlich-technologische Grundlagen der Elektromobilität –
HGP-E for financial support.
2
C1(sp ) bond distance is a bit shorter than distances to methyl
groups. Similar orientation of the sulfur lone pair and similar
bond distances are detected for compound
5
, as well as for
]. S1-C(sp ) bond distances in the same
range were observed in non-ionic ferrocenyl phenyl sulfide
3
4
2
2 3
[Cr(CpSMe )(CO)
Experimental Section
3
5
Methods and Devices.
with 1.749(5) Å or bis(phenylthio)ferrocene with 1.753(2) Å;
2
C(sp )
S1−
cyclopentadienylide is slightly shorter: 1.712(8) Å. A similar
of
non-coordinated
dimethylsulfonium
3
All synthetic steps, expect of the extraction with water and
column chromatography, were conducted using standard
Schlenk techniques. Elemental analyses (C, N, H, S) were
carried out by the service department for routine analysis and
mass spectrometry with a vario MICRO cube (Elementar). The
samples were weighted into tin capsules inside a nitrogen
filled glove box. Melting points and decomposition
temperatures were determined with a Büchi Melting Point
B540, a METTLER TOLEDO TGA/DSC 3+ and a METTLER
6
trend was observed for alkylferrocenylposphonium ions and
4
ylids. Within the S-functionalized ring of
4 the pair of
distances C1-C2 (1.433(3) Å and C1-C5 (1.435(3) Å) adjacent to
the onium substituent is slightly elongated in comparison to
the pair C2-C3 (1.413(3) Å) and C4-C5 (1.413(3) Å) while C3-C4,
most remote to the S-substituent, is 1.427(3) Å. In
average C-C bond adjacent to S is 1.425 Å.
5 the
1
13
TOLEDO DSC 1, respectively. H, proton decoupled C and
1
9
F NMR spectra were recorded at 300 K in automation with a
Bruker Avance III 300 spectrometer and were calibrated using
CN: δ 1.94 ppm, δ
128.06 ppm; CDCl : δ
77.16 ppm) or externally against CFCl . IR
Conclusions
Several unprecedented ferrocenylsulfonium ionic liquids were residual proton and solvent signals (CD
prepared by an atom economic alkylation with alkyl 1.32 ppm, C : δ 7.16 ppm, δ
bis(trifluoromethanesulfonyl)imides and release of the TFSI 7.26 ppm, δ
3
H
C
6
D
6
H
C
3
H
3
7
C
3
anion. This synthetic strategy requires relatively cheap starting spectra were recorded on a Bruker APLPHA FT-IR spectrometer
materials and guarantees high purity ILs free from with Platinum ATR-sampling (diamond single crystal). HR-ESI
electroactive water, metal and halogen ion impurities even at mass spectra were acquired with a LTQ-FT Ultra mass
large scales. Both, room temperature ILs as well as crystal spectrometer (Thermo Fischer Scientific). The resolution was
structures of ferrocenylsulfonium salts, are presented and set to 100.000.
discussed.
The influence of the substituents at the sulfur atom on its 2048 photometer in a glovebox. The probes were dissolved in
electrochemical, thermal and absorption behavior was acetonitrile and measured at room temperature.
UV-Vis spectroscopy was performed with an Avantes AvaSpec-
investigated. Due to the positive charge located at the Cyclic voltammetry experiments were carried out with a RHD
sulfonium ion and its electron withdrawing effect, the Instruments Microcell HC and a Metrohm Autolab PG Stat 204
potentials of the prepared ionic liquids are shifted by about in a nitrogen flushed glove box at 24.5 ± 0.7 °C. The ionic
−
1
0
.53 V (av.) to higher values versus ferrocene standard. The compounds were solved in [EMIM]TFSI (c = 3.6-11.7 mmol L )
shift is more pronounced than in corresponding and the resulting solutions were placed in a platinum crucible,
alkylphosphonium substituted ferrocenes. For 1,1’- which acted as counter electrode. As working electrode a
disubstituted ferrocenes, this effect is almost doubled. With platinum wire (ø = 0.25 mm) was used and as reference
3
8
respect to this tunable potential, a low absorbance in the electrode a 100 mM Ag/AgTFSI in [EMIM]TFSI. Both platinum
visible light, low melting points and enhanced thermal electrodes were polished with Kemet diamond paste (0.25 µm)
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 6 of 10
View Article Online
DOI: 10.1039/C7DT04139J
ARTICLE
Journal Name
3
3
), 4.81 (t, 2H, JHH = 2.0 Hz, CH
prior use. The potentials were calibrated against (t, 2H, JHH = 2.0 Hz, CH
β
α
) ppm.
1
3
ferrocene/ferrocenium by addition of small amounts of
ferrocene to the solution or by measurement of a ferrocene
solution in [EMIM]TFSI after measurement. All data were
detected at a scan rate of 10 mV s−1 unless mentioned
otherwise.
3 3 α
C NMR (CD CN): δ = 31.0 (CH ), 70.0 (C ), 71.8 (Cp'), 73.6
1
19
(
(
β 3
C ), 75.1 (CS), 121.0 (q, JCF = 308.7 Hz, CF ) ppm. F NMR
–
1
CD CN): δ =
3
−81.0 ppm. ESI-HRMS(+): m·z calculated for
+
–1
C
12
H
15FeS : 247.0239, found: 247.0240. ESI-HRMS(
−
−
): m·z
calculated for C F S O N : 279.9178, found: 279.9178.
2
6
2
4
The data collection for the single crystal structure
determinations was performed on a Bruker D8 QUEST
Preparation
of
butylferrocenylmethylsulfonium
3
9
bis(trifluoromethanesulfonyl)imide 1b. The preparation was
performed analogous to 1a with 175 mg (0.638 mmol,
1.00 eq.) butyl ferrocenyl sulfide and 628 mg (2.13 mmol,
3.33 eq.) Me-TFSI and a reaction time of 44 h. 363 mg
(0.621 mmol, 97%) 1b were obtained as orange oil. Elem. anal.
diffractometer. Bruker software (APEX2, SAINT) was used for
data collection, cell refinement and data reduction. The
4
structures were solved with SIR2014 refined with SHELXL-
0
4
1
42
014 and finally validated using PLATON software, all
2
4
3
within the WinGX software bundle. Absorption corrections
were applied beforehand within the APEX2 software (multi-
4
scan). Graphic representations were created using Diamond
found C, 35.7; H, 3.7; N, 2.6; S, 17.0; C17
–
569.38 g mol ) requires C, 35.9; H, 3.7; N, 2.5; S, 16.9. IR
H
24
F
6
FeNO
4 3
S
1
4
(
4
.
5
H-atoms were constrained to parent site. In all graphics (liquid film): ṽ /cm− = 3112 w, 3032 vw, 2967 w, 2938 w, 2879,
1
4
the ellipsoids are shown for the 50% probability level. w, 1468 vw, 1416 w, 1347 s, 1329 m, 1226 w, 1176 vs, 1132 vs,
Crystallographic data for the structures reported in this paper 1107 w, 1050 vs, 1003 m, 982 w, 919 vw, 885 w, 828 m, 787 m,
are supplied as supporting information and have been 762 w, 739 m, 653 w, 612 s, 599 s, 569 s, 507 s, 490 s, 460 w,
1
3
deposited with the Cambridge Crystallographic Data Centre
CCDC 1583349 and 1583350).
4
44 m, 408 vw. H NMR (CD
3
CN): δ = 0.90 (t, 3H, JHH = 7.2 Hz,
3
), 1.41 (qt, 2H, JHH = 7.4, 7.4 Hz, CH
(
CH
2
CH
3
2
CH ), 1.53-1.64 (m,
3
2
2
H, CH CH CH ), 3.12 (s, 3H, SCH ), 3.17 (dt, 1H, J = 12.4 Hz,
2 2 3 3 HH
3
2
3
Starting Materials.
J
HH = 7.2 Hz, SCH
2
), 3.35 (dt, 1H, JHH = 12.5 Hz, JHH = 7.8 Hz,
4
6
SCH ’), 4.47 (s, 5H, CHCp’), 4.72-4.77 (m, 3H, CHα+β+β'), 4.82-4.83
2
All solvents were dried according to common procedures and
passed through columns of aluminum oxide, 3 Å molecular
1
3
(
m, 1H, CH
CH ), 26.2 (CH
and 71.1 (Cp'), 71.8 (CS), 72.4 (C ’), 72.9 (C ), 73.2 (C '), 119.9 (vq,
α
) ppm. C NMR (CDCl
3
): δ = 13.5 (CH
2
CH
3
), 21.3
sieve and R3-11G-catalyst (BASF) or stored over molecular (CH
sieve (3 or 4 Å) until use. n-Butyl-
methylbis(trifluoromethanesulfonyl)imides R’TFSI,
CH CH ), 26.8 (SCH
), 48.4 (SCH ), 66.4 (C
),
2
3
2
2
3
3
2
α
α
β
β
4
,47
25
1
52
13
1,1’-
JCF = 323.6 Hz, CF3) ppm. C NMR (CD CN): δ = 13.6
3
2
5
bis(methylthio)ferrocene, phenyl ferrocenyl sulfide, butyl (CH CH ), 21.9 (CH CH ), 26.7 (CH CH CH ), 27.1 (SCH ), 48.4
2
3
2
3
2
2
3
3
4
8
25
ferrocenyl
sulfide,
1
bis(phenylthio)ferrocene
and
(
SCH
2
), 67.8 (C
α
), 71.9 (Cp'), 73.1 (CS), 73.2 (C
α
’
'
), 73.8 (Cβ+β ),
5
bromoferrocene were synthesized according to literature
1
21.0 (vq, J = 321.2 Hz, CF3) ppm. F NMR (CD CN): δ =
52
19
1
CF
3
2
procedures. For ferrocenyl methyl sulfide and diferrocenyl
5
): m·z− calculated for C15
1
21FeS+:
−
2
78.9 ppm. ESI-HRMS(+
89.0709, found: 289.0708. ESI-HRMS(
H
4
sulfide modified procedures are described. Literature known
9
): m·z− calculated for
1
−
5
0
1,1’-di(butylthio)ferrocene
was prepared by a method
−
C
2
F
6
S
2
O
4
N : 279.9178, found: 279.9178.
reported for 1,1’-bis(methylthio)ferrocene. Details for these
starting materials are given in the supporting information.
X-Ray suitable crystals of ferrocenyldimethylsulfonium iodide
Preparation
of
ferrocenylmethylphenylsulfonium
bis(trifluoromethanesulfonyl)imide 1c. The preparation was
performed analogous to 1a with 212 mg (0.721 mmol
2
2
were obtained by the synthesis according to Watts.
1.00 eqn.) ferrocenyl phenyl sulfide and 558 mg (1.89 mmol,
2.62 eq.) Me-TFSI. 283 mg (0.48 mmol, 67%) 1c were obtained
Synthetic Procedures.
as yellow oil, which crystallized after a period of several
Preparation of dimethylferrocenylsulfonium bis(trifluoromethane-
sulfonyl)imide 1a. To 1.5 equivalents of Me-TFSI, 1.0
equivalents of ferrocenyl methyl sulfide were added and the
resulting mixture was stirred for 18 h at 90 °C. The crude
product was washed with 10 mL pentane and afterwards it
was dissolved in 10 mL of acetonitrile. After addition of
charcoal, the suspension was stirred for 1 h, filtered and the
-
months. Mp: 55.1 °C (1.0 K min ). Elem. anal. found C, 38.8; H,
1
−
1
2
.8; N, 2.5; S, 16.9; C19
17 6 4 3
H F FeNO S (589.37 g mol ) requires:
–
1
C 38.7, H 2.9, N 2.4, S 16.3. IR (liquid film): ṽ /cm = 3112 w,
3
1
032 vw, 2942 vw, 1478 vw, 1447 w, 1414 w, 1347 s, 1328 s,
226 w, 1175 vs, 1131 vs, 1108 w, 1049 vs, 1000 w, 976 m, 883
w, 835 m, 787 m, 748 m, 739 m, 713 vw, 684 m, 652 w, 610 s,
1
598 s, 569 s, 498 ssh, 477 s, 448 w, 433 m, 405 vw. H NMR
-4
solvent was removed at 60 °C in vacuum (10 mbar). 1a (81%)
(
CDCl
CH ), 4.78 (br, 1H, CH
7.4 Hz, Hmeta), 7.68-7.74 (m, 3H, Hortho, Hpara) ppm. H NMR
CD CN): δ = 3.46 (s, 3H, CH ), 4.44 (s, 5H, CHCp’), 4.75 (dt, 1H,
HH = 1.3, 2.6 Hz, CH ), 4.79 (dt, 1H, JHH = 1.3, 2.7 Hz, CH
3
): δ = 3.49 (s, 3H, CH
3
), 4.46 (s, 5H, CHCp’), 4,72 (br, 2H,
was obtained as yellow oil. Elem. anal. found C, 31.8; H, 2.8; N,
3
−
1
.9: S 18.55: C H F FeNO S (512.27 g mol ) requires C, 31.9;
H, 2.9; N; 2.7; S, 18.2. IR (liquid film): ṽ /cm− = 3110 vw, 3029
β
α
), 4.99 (br, 1H, CH
), 7.62 (t, 2H, JHH =
α
2
14 15 6 4 3
1
1
(
3
3
vw, 2937 vw, 1415 w, 1346 s, 1327 m, 1225 w, 1176 vs, 1132
vs, 1107 w, 1050 vs, 998 m, 885 w, 825 m, 787 m, 762 w, 739
m, 653 w, 611 s, 599 s, 569 s, 504 s, 490 s, 442 m, 408 vw.
3
3
J
β
β
),
), 4.96 (dt, 1H, JHH = 1.3,
2.6 Hz, CH ), 7.62-7.68 (m, 2H, Hmeta), 7.71-7.78 (m, 3H, Hortho
3
3
4
.81 (dt, 1H, JHH = 1.3, 2.6 Hz, CH
α
1
,
H NMR (CD CN): δ = 3.03 (s, 6H, CH ), 4.47 (s, 5H, CHCp’), 4.72
3
α
3
6
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 7 of 10
Plea sDe a dl t oo nn oT tr aa nd sj ua cs tt i om nasrgins
View Article Online
DOI: 10.1039/C7DT04139J
Journal Name
ARTICLE
1
3
–1
(631.45 g mol ) requires C,
), 75.3 (CS), 121,0 (vq, 41.85; H 3.7; N, 2.2; S, 15.2. IR (liquid film): ṽ /cm− = 3112 vw
52
), 129.6 (Cipso), 130.1 (Cmeta), 131.9 (Cortho), (CH), 2965 w (CH), 2937 vw (CH), 2878 vw (CH), 1467 vw, 1447
3
H
para) ppm. C NMR (CD
3
CN): δ = 30.9 (CH
3
), 68.5 (Cp
α
), 72.1 N, 2.7; S, 15.4; C22
H
23
F
6
FeNO
4
S
3
1
(
Cp'), 72.4 (Cp ), 73.9 (Cp
'
α
β
), 74.6 (Cp
β
'
1
J
CF = 320.9 Hz, CF
19
1
35.2 (Cpara) ppm. F NMR (CD
1
3
CN): δ =
+
−
80.1 ppm. ESI- w, 1416 vw, 1347 s, 1329 m, 1226 m, 1176 vs, 1132 s, 1108 w,
HRMS
(
+
09.0395. ESI-HRMS(
): m·z− calculated for C17
H
17FeS : 309.0395, found: 1050 s, 1022 w, 1000 w, 922 vw, 883 vw, 833 m, 787 m, 750 w,
3
−
79.9178, found: 279.9173.
): m·z− calculated for C
1
2
F
6
S
2
O
4
N :
−
7
39 m, 686 m, 652 w, 611 s, 598, s, 569 s, 499 m, 480 m, 433
1
3
vw, 405 vw. H NMR (CD
CH ), 1.44-1.60 (m, 2H, CH
.74-3.83 (m, 2H, SCH
3
CN): δ = 0.91 (t, 3H, JHH = 7.2 Hz,
CH ), 1.64-1.72 (m, 2H, CH CH CH ),
2
Preparation of diferrocenylmethylsulfonium bis(trifluoro-
3
2
3
2
2
3
3
2
), 4.30 (s, 5H, Cp’), 4.72-4.75 (m, 2H,
methanesulfonyl)imide 1d The preparation of 1d was
performed analogous to 1a with 123 mg (0.306 mmol 1.00 eq.) CH
3
α
Ph+βPh), 4.77 (dt, 1H, JHH = 1.3, 2.6 Hz, CH
β
Bu), 4.97 (dt, 1H,
3
3
diferrocenyl sulfide and 286 mg (0.969 mmol, 3.17 eq.) Me-
JHH = 1.2, 2.6 Hz, CH Bu), 7.72 (t, 2H, JHH = 7.9, Hortho), 7.82 (tt,
TFSI and a reaction time of 3 d. 142 mg (0.204 mmol, 67%) 1d 1H, J = 7.5, J = 1.2, H ), 7.88 (dd, 2H, J = 8.4, J
=
HH
α
3
5
3
5
HH
HH
para
HH
1
3
were obtained as dark orange oil. Elem. anal. found C, 39.2; H, 1.0, Hmeta) ppm. C NMR (CD CN): δ = 13.6 (CH ), 21.9
3
3
−
1
.0; N, 2.1; S, 14.1; C H F Fe NO S (697.29 g mol ) requires
C, 39.6; H, 3.0; N, 2.0; S, 13.8. IR (liquid film): ṽ /cm− = 3109 w,
3
23 21 6 2 4 3
(CH CH ), 27.4 (CH CH CH ), 48.0 (SCH ), 70.8 (CpαPh), 71.0
2
2
3
2
2
3
1
(
(
(
Cp
α
Bu), 72.1 (Cp’), 73.6 (Cp
β
β
Bu), 74.4 (Cp Ph), 75.0 (CS), 126.8
53 19
2
1
7
4
942 vw, 1414 w, 1394 vw, 1347 s, 1329 s, 1225 w, 1176 vs,
132 vs, 1107 w, 1049 vs, 1004 w, 972 m, 881 w, 827s, 787 m,
61 w, 738 m, 652 m, 612 s, 598 s, 568 s, 506 s, 487 s, 447 s,
Cipso), 131.6 (Cmeta), 132.1 (Cortho), 135.8 (Cpara) ppm.
F NMR
80.2 ppm. ESI-HRMS(+): m·z− calculated for
1
CD
3
CN): δ =
+
−
23FeS : 351.0865, found: 351.0864. ESI-HRMS(
–1
1
C
20
H
−
): m·z
04 vw. H NMR (CD CN): δ = 3.39 (s, 3H, CH ), 4.40 (s, 10H,
3
3
−
2 6 2 4
calculated for C F S O N : 279.9178, found: 279.9173.
Cp’), 4.69-4.73 (m, 4H, CHβ+β’), 4.74 (dt, 2H, JHH = 1.3, JHH
Preparation of diferrocenylmethylsulfonium tetrafluoro-
borate 3. 195 mg (0.485 mmol, 1.0 eq.) diferrocenyl sulfide
were solved in 3 mL dichloromethane and the solution was
cooled to 0°C. A solution of 73 mg (0.49 mmol, 1.0 eq.)
trimethyloxonium tetrafluoroborate in 2 mL dichloromethane
were added dropwise over 10 min. The solution was stirred for
=
2.6 Hz, CH ), 4.82 (dt, 2H, J = 1.2, JHH = 2.5 Hz, CH ) ppm.
α HH α
1
3
C NMR (CD CN): δ /ppm = 32.5 (CH ), 68.6 (Cp ), 71.5 (Cp ),
α
3
3
α
7
1.9 (Cp’), 73.5 (Cp ), 73.5 (Cp ), 78.6(CS), 121.1 (vq,
β β
19
1
52
JCF = 321.5 Hz, CF ) ppm. F NMR (CD CN): δ =
−
79.5 ppm.
3
3
): m·z− calculated for C H Fe S: 417.0058, found:
1
ESI-HRMS
(
+
2
1
21
2
): m·z− calculated for C F NO S :
(−
2 6 4 2
1
−
4
17.0048. ESI-HRMS
79.9178, found: 279.9173.
1
8 h while it warmed up to room temperature. The solvent
2
was removed in vacuum, the residue was solved in acetonitrile
and the product was crystallized by layering with THF and
Preparation of dibutylferrocenylsulfonium bis(trifluoromethane-
sulfonyl)imide 1e The preparation of 1e was performed
analogous to 1a with 158 mg (0.577 mmol 1.00 eqn.) butyl
ferrocenyl sulfide and 448 mg (1.33 mmol, 2.30 eqn.) nBu-TFSI
and a reaction time of 44 h. 328 mg (0.536 mmol, 93%) 1e
were obtained as yellow orange oil. Elem. anal. found C, 38.8;
diethyl ether. 85 mg (0.16 mmol, 32%)
3 containing one
equivalent of acetonitrile were obtained as orange needles.
Mp: 130.7 °C (2.0 K min ). IR (neat): ṽ /cm− = 3097 w, 3030
-
1
1
vw, 1413 m, 1390 w, 1368 vw, 1322 w, 1283 w, 1215 w, 1162
–
1
m, 1025 vssh, 974 w, 889 w, 829 ssh, 738 w, 638 vw, 487 vs,
H, 4.4; N, 2.5; S, 16.1; C20
requires C, 39.3; H, 4.45; N, 2.3; S, 15.7. IR (liquid film): ṽ /cm−
27 6 4 3
H F FeNO S (611.46 g mol )
1
4
47 vs. H NMR (CD
3
CN): δ = 3.40 (s, 3H, CH
), 4.74-4.76 (m, CH
’) ppm. C NMR (CD CN): δ = 32.4 (CH
), 71.5 (Cp ), 71.9 (Cp’), 73.5 (Cp ), 73.5 (Cp ), 78.7 (CS)
CN): δ = 152.4 ppm. ESI-HRMS
S: 417.0058, found: 417.0058.
1,1’-bis(dimethylsulfonium)ferrocene
3
), 4.40 (s, 10H,
), 4.82-4.84
), 68.6
1
Cp’), 4.69-4.72 (m, 4H, CHβ+β
’
α
=
1
9
5
3109 vw, 2966 w, 2937 w, 2878 vw, 1467 w, 1415 w, 1346 s,
13
(
m, 2H, CH
Cp
α
3
3
329 m, 1225 w, 1177 vs, 1133 vs, 1108 w, 1051 vs, 1005 w,
(
α
α
’
β
β’
20 vw, 885 vw, 835 m, 787 m, 761 w, 738 m, 652 m, 613 s,
1
99 s, 569 s, 508 ssh, 461 w, 443 vw, 405 vw. H NMR (CD
19
–1
ppm. F NMR (CD
3
−
(+): m·z
3
CN):
calculated for C20H18Fe
2
3
3
δ = 0.95 (t, 6H, JHH = 7.3 Hz, CH
3
), 1.48 (tq, 4H, JHH = 7.4,
CH CH
), 3.47 (dt, 2H, JHH = 7.6 Hz, 2a was performed analogous to 1a with 147 mg (0.529 mmol
’), 4.46 (s, 5H, Cp’), 4.74 (s br, 4H, Cpα+β
1.00 eq.) 1,1’-di(methylthio)ferrocene and 569 mg (1.93 mmol,
Preparation
of
7
.4 Hz, CH CH ), 1.64-1.75 (m, 4H, CH
2
3
3
2
2
3
), 3.30 (dt, 2H, di{bis(trifluoromethanesulfonyl)imide} 2a. The preparation of
2
3
J
HH =12.9 Hz, JHH = 7.8 Hz, SCH
2
2
J
HH = 12.9 Hz, SCH
1
2
)
3
ppm. C NMR (CD CN): δ = 13.6 (CH ), 22.1 (CH CH ), 27.0 3.65 eq.) Me-TFSI. 318 mg (0.366 mmol, 69%) 2a were
3
3
2
3
obtained
as
yellow orange
solid.
Mp:
83.7 °C
(
CH
2
CH
2
CH
3
), 45.0 (SCH
2
), 70.7 (Cp
α
or
β
), 71.9 (Cp'), 72.8 (CS),
52
-
(1.0 K min ). Elem. anal. found C, 24.9; H, 2.4; N, 3.25; S, 22.6;
1
1
), 121.0 (vq, JCF = 320.0 Hz, CF
19
ppm. F NMR
7
3.7 (Cp
α
or
β
3
)
–
1
): m·z− calculated for
1
18 20 2 8 6
C H F12FeN O S (868.58 g mol ) requires C, 24.9, H 2.3, N
(CD
3
CN): δ = −
+
27FeS : 331.1178, found: 331.1171. ESI-HRMS(
80.2 ppm. ESI-HRMS(
+
–1
): m·z−1
3.2, S 22.15. IR (neat): ṽ /cm = 3117 w, 3033 w, 2943 vw,
C
18
H
−
1
1
5
1
=
419 w, 1344 s, 1327 w, 1223 vw, 1172 vs, 1135 s, 1049 vs,
calculated for C
2
F
6
NO
of
4
S
2
−: 279.9178, found: 279.9174.
000 m, 891 w, 871 w, 837 m, 790 m, 763 w, 740 m, 609 s,
1
69 s, 513 s, 438 vw, 409 vw. H NMR (CD
Preparation
butylferrocenylphenylsulfonium
3
CN): δ = 3.07 (s,
bis(trifluoromethanesulfonyl)imide 1f. The preparation of 1f
was performed analogous to 1a with 225 mg (0.765 mmol
3
3
), 5.09 (t, 4H, JHH
2H, CH
2.0 Hz, CH
), 75.7 (Cp
3
), 4.98 (t, 4H, JHH = 2.0 Hz, CH
β
13
α
) ppm. C NMR (CD
3
), 78.3 (CS), 120,9 (vq, JCF = 322.2 Hz, CF )
3
CN): δ = 30.6 (CH ), 72.5
1
3
52
1
.00 eq.) ferrocenyl phenyl sulfide and 472 mg (1.40 mmol,
(Cp
α
β
19
−
1
1
.83 eq.) nBu-TFSI. 150 mg (0.238 mmol, 31%) 1f were
ppm. F NMR (CD
3
CN): δ = −80.7 ppm. ESI-HRMS(+): m·z
obtained as yellow orange oil. Elem. anal. found C, 41.0; H, 3.6;
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 7
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 8 of 10
View Article Online
DOI: 10.1039/C7DT04139J
ARTICLE
Journal Name
calculated for C16
H
20
1
F
6
FeNO
4
S
4
+: 587.9524, found: 587.9523.
NO
−: 279.9178,
Notes and references
−
ESI-HRMS
(
−
found: 279.9172.
): m·z
calculated for C
2
F
6
4 2
S
1
2
3
4
5
L. S. Hernández-Muñoz and F. J. González, Electrochem.
Commun., 2011, 13, 701–703.
Preparation
of
1,1’-bis(dimethylsulfonium)ferrocene
di(tetraphenylborate) ∙ THF 5.
53 mg (1.19 mmol, 3.25) Me-TFSI were added to 102 mg
0.367 mmol, 1.00 eq.) 1,1’-di(methylthio)ferrocene, and the
M. Armand, Y. Choquette, M. Gauthier and C. Michot, EP 0
3
8
50 920 A2, 1998.
C. B. Bouvet and H. Krautscheid, Eur. J. Inorg. Chem., 2016,
016, 4573–4580.
P. Kübler and J. Sundermeyer, Dalt. Trans., 2014, 43, 3750–
766.
(
solution was stirred for 18 h at 100 °C. After cooling, the
mixture was washed with 10 mL pentane and dried in vacuum
at 90 °C. The residual oil was dissolved in THF and 252 mg
2
3
(0.734 mmol, 2.00 eq.) of sodium tetraphenylborate were
B. Gelinas, J. C. Forgie, D. Rochefort, G. Bruno, J. C. Forgie
and D. Rochefort, J. Electrochem. Soc., 2014, 161, H161–
H165.
added. The solution was stirred for 1 h. After removing the
solvent in vacuum the residue was washed with 2 mL nitrogen
saturated water and all volatile compounds were removed in
6
7
Y. Gao, B. Twamley and J. M. Shreeve, Inorg. Chem., 2004,
vacuum. 72 mg (71 μmol, 19%)
5 were obtained as X-ray
4
3, 3406–3412.
suitable crystals by crystallization from acetonitrile/
THF/diethyl ether. Elem. anal. found C, 77.15; H, 6.5; S, 6.9;
J. E. F. Weaver, D. Breadner, F. Deng, B. Ramjee, P. J.
Ragogna and R. W. Murray, J. Phys. Chem. C, 2011, 115,
–
1
C
66
H
68
B
2
FeOS
2
(1018.84 g mol ) requires C, 77.8; H, 6.7; S, 6.3.
1
9379–19385.
–
IR (neat): ṽ /cm = 3107 vw, 3078 vw, 3052 m, 3000 m, sh,
1
8
9
1
1
1
V. O. Nyamori, M. Gumede and M. D. Bala, J. Organomet.
Chem., 2010, 695, 1126–1132.
2
916 vw, 1578 w, 1476 m, 1415 m, 1396 m, 1325 vw, 1303 vw,
261 w, 1175 w, 1123 w, 1063 w, 1032 m, 987 w, 918 vw, 887
1
J.-L. Thomas, J. Howarth, K. Hanlon and D. McGuirk,
Tetrahedron Lett., 2000, 41, 413–416.
vw, 833 w, 811 vw, 750 m, 731 s, 707 vs, 624 vw, 611 s, 510 m,
1
4
3
95 m, 469 w, 453 vw, 442 w. H NMR (CD CN): δ = 1.81 (t, 4H,
0
1
2
Y. Miura, F. Shimizu and T. Mochida, Inorg. Chem., 2010,
3
3
J
HH = 6.0 Hz, THF 2/3 CH
5.7 Hz, THF 1/4 CH ), 4.92 (sbr, 4H, CH
.85 (t, 8H, JHH = 6.4 Hz, CHpara), 7.00 (t, 16H, JHH = 6.8 Hz,
2
), 2.98 (s, 12H, CH
3
), 3.65 (t, 4H, JHH
4
9, 10032–10040.
B. Gélinas and D. Rochefort, Electrochim. Acta, 2015, 162,
6–44.
=
6
2
β
), 5.01 (sbr, 4H, CH
α
),
3
3
3
1
3
3
CHmeta), 7.28 (sbr, 16H, CHortho) ppm. C NMR (CD CN): = 30.6
O. Fontaine, C. Lagrost, J. Ghilane, P. Martin, G. Trippé, C.
Fave, J. C. Lacroix, P. Hapiot and H. N. Randriamahazaka, J.
Electroanal. Chem., 2009, 632, 88–96.
3 α β
(CH ), 72.4 (Cp ), 75.7 (Cp ), 78.3 (CS), 122.8 (Cpara), 126.7
5
4
): m·z− calculated for
1
(
C
meta), 136.8 (Cortho). ESI-HRMS
(
+
2
+
(−
): m·z−
1
C
14
H
20FeS
calculated for C24
Preparation of
2
: 154.0172, found: 154.0169. ESI-HRMS
20B: 319.1668, found: 319.1657.
1,1’-di(butylmethylsulfonium)ferrocene
1
1
1
1
1
1
3
4
5
6
7
8
B. Gélinas, M. Natali, T. Bibienne, Q. P. Li, M. Dollé and D.
Rochefort, J. Phys. Chem. C, 2016, 120, 5315–5325.
J. Ghilane and J. C. Lacroix, J. Am. Chem. Soc., 2013, 135,
H
di{bis(trifluoromethanesulfonyl)imide} 2b. The preparation
was performed analogous to 1a with 187 mg (0.516 mmol,
4
722–4728.
J. C. Forgie, S. El Khakani, D. D. MacNeil and D. Rochefort,
Phys. Chem. Chem. Phys., 2013, 15, 7713–7721.
H. J. Xie, B. Gélinas and D. Rochefort, Electrochem.
commun., 2016, 66, 42–45.
1.00 eq.) 1,1’-di(butylthio)ferrocene and 406 mg (1.37 mmol,
2.66 eq.) Me-TFSI. 372 mg (0.391 mmol, 76%) 2b were
obtained as dark red solid. A further purification can be
accomplished by solving the product in dichloromethane and
H. Tahara, R. Baba, K. Iwanaga, T. Sagara and H. Murakami,
Chem. Commun., 2017, 53, 2455–2458.
-1
precipitation with hexane. Mp: 93.0 °C (10 K min ). Elem. anal.
32 2 8 6
found C, 30.5; H, 3.4; N, 3.1: S, 20.25; C24H F12FeN O S
Y. Funasako, T. Inagaki, T. Mochida, T. Sakurai, H. Ohta, K.
Furukawa and T. Nakamura, Dalton Trans., 2013, 42, 8317–
–
1
(
952.74 g mol ) requires C, 30.3; H, 3.4; N, 2.9; S, 20.2. IR
–1
(
neat): ṽ /cm = 3117 vw, 3023 vw, 2969 w, 2940 w, 2880 vw,
8
327.
1
9
6
469 vw, 1423 w, 1344 s, 1329 w, 1181 vs br, 1134 s, 1047 vs,
1
2
9
0
D. Gerhard, S. C. Alpaslan, H. J. Gores, M. Uerdingen and P.
Wasserscheid, Chem. Commun., 2005, 5080–5082.
85 w, 892 w, 872 vw, 836 m, 791 m, 763 w, 739 m, 654 vw,
1
10 vs, 569 s, 511 s, 438 vw, 408 w. H NMR (CD
3
CN): δ = 0.91
HH = 7.2, 7.2 Hz,
), 3.14 (s, 6H, SCH ),
), 3.39 (dt, 2H, JHH = 7.8 Hz, JHH = 12.2 Hz,
’), 4.99 (s, 4H, Cp), 5.03 (s br, 2H, Cp), 5.11 (s br, 2H, Cp)
H. B. Han, J. Nie, K. Liu, W. K. Li, W. F. Feng, M. Armand, H.
Matsumoto and Z.-B. Zhou, Electrochim. Acta, 2010, 55,
3
3
(t, 6H,
J
HH = 7.1 Hz, CH
3
), 1.42 (tq, 4H,
CH CH
J
CH
2
CH
3
), 1.53-1.65 (m br, 4H, CH
2
3
2
3
3
1
221–1226.
2
3.22 (m, 2H, SCH
2
2
2
1
2
E. Coadou, P. Goodrich, A. R. Neale, L. Timperman, C.
SCH
2
Hardacre, J. Jacquemin and M. Anouti, ChemPhysChem,
1
3
ppm. C NMR (CD
SCH or CH CH CH
CH CH CH ), 48.4 (SCH
5.2 (Cp ), 75.5 (Cp ), 75.9 (Cp
CS), 121,0 (vq, JCF = 322.4 Hz, CF
3
CN): δ = 13.5 (CH
), 26.5 (SCH or CH
), 48.4 (SC’H
2
CH
CH
), 70.3 (Cp
3
), 21.9 (CH
CH ), 26.6 (SCH
), 70.5 (Cp
), 76.5 (CS), 76.5
2
CH
3
), 26.5
or
),
2
016, 17, 3992–4002.
(
3
2
2
3
3
2
2
3
3
G. R. Knox, I. G. Morrison, P. L. Pauson, M. A. Sandhu and
W. E. Watts, J. Chem. Soc. C, 1967, 1853–1856.
2
2
3
2
2
α
α
7
α
α
β
), 76.0 (Cp
β
2
2
3
4
G. Marr and M. T. White, J. Chem. Soc. C, 1970, 1789–1792.
N. L. Holy, T. Nalesnik, L. Warfield and M. Mojesky, J.
Coord. Chem., 1983, 12, 157–162.
1
52
19
(
3
)
ppm. F NMR (CD
3
CN): δ
calculated for
: 672.0463, found: 672.0456. ESI-HRMS ):
−79.0 ppm. ESI-HRMS(+
): m·z−
1
=
C
+
22
H
32FeNO
4
S
4
(−
2
5
S. Minière, V. Reboul, R. G. Arrayás, P. Metzner and J. C.
−
1
−
2 6 2 4
m·z calculated for C F S O N : 279.9178, found: 279.9172.
8
| J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 9 of 10
Plea sDe a dl t oo nn oT tr aa nd sj ua cs tt i om nasrgins
View Article Online
DOI: 10.1039/C7DT04139J
Journal Name
ARTICLE
Carretero, Synthesis (Stuttg)., 2003, 2249–2254.
L. Wang and Z. Huang, J. Zhejiang Univ. Sci., 2005, 6A, 636– 49
39.
pp. 889–929.
2
2
2
2
3
3
3
6
7
8
9
0
1
2
D. C. O’Connor Salazar and D. O. Cowan, J. Organomet.
Chem., 1991, 408, 227–231.
6
R. Sanders and U. T. Mueller-Westerhoff, J. Organomet. 50
Chem., 1996, 512, 219–224.
M. Sato, M. Sekino, M. Katada and S. Akabori, J.
Organomet. Chem., 1989, 377, 327–331.
T. E. Pickett and C. J. Richards, Tetrahedron Lett., 1999, 40, 51
D. A. Khobragade, S. G. Mahamulkar, L. Pospíšil, I.
Císařcová, L. Rulíšek and U. Jahn, Chem. Eur. J., 2012, 18,
12267–12277.
5251–5254.
G. Wilkinson, M. Rosenblum, M. C. Whiting and R. B.
Woodward, J. Am. Chem. Soc., 1952, 74, 2125–2126.
A. I. Popov and R. F. Swensen, J. Am. Chem. Soc., 1955, 77,
1
3
52
53
54
Due to the low concentration, the C CF
3
signal was only
detected as doublet (part of quartet).
1
3
3724–3726.
Due to the low concentration, the C CF signal of TFSI was
3
S. Lu, V. V. Strelets, M. F. Ryan, W. J. Pietro and A. B. P.
not detected.
1
3
Lever, Inorg. Chem., 1996, 35, 1013–1023.
At low concentration, the C Phipso signal was not detected
1
1
Crystal Data for 4: C12
H
15FeIS, M=374.05, monoclinic,
= 90°,
= 90°, V = 1305.81(9) Å , T = 100(2) K,
/c, Z = 4, 25189 reflections measured, 2890
unique (Rint = 0.0583). 0.0186,
= 0.0376, GoF = 1.045, CCDC: 1583350.
Crystal Data for 5: C66 FeOS , M = 1018.79, triclinic,
a = 11.0520(5) Å, b = 14.8221(6) Å,
= 104.7890(13)°, = 104.0025(14)°,
due to coupling with B .
a = 15.4360(6) Å, b = 9.5323(4) Å, c = 8.8874(3) Å,
α
3
β
= 93.0790(10)°, γ
space group P2
1
reflections
wR
1
R =
2
33
H
68
B
2
2
c = 18.5056(7) Å,
α
β
γ
= 105.4496(14)°,
3
ꢁ
V = 2664.29(19) Å , T = 100(2) K, space group P1, Z = 2,
6302 reflections measured, 11807 reflections unique
int = 0.0325). R = 0.0321, wR = 0.0766, GoF = 1.031,
CCDC: 1583349.
7
(R
1
2
34
V. G. Andrianov, Y. T. Struchkov, V. N. Setkina, A. Z.
Zhakaeva and V. I. Zdanovitch, J. Organomet. Chem., 1977,
1
40, 169–175.
J. A. Adeleke, Y. W. Chen and L. K. Liu, Organometallics,
992, 11, 2543–2550.
V. G. Andrianov and Y. T. Struchkov, Russ. Chem. Bull.,
977, 26, 624–626.
35
36
37
1
1
G. R. Fulmer, A. J. M. Miller, N. H. Sherden, H. E. Gottlieb,
A. Nudelman, B. M. Stoltz, J. E. Bercaw and K. I. Goldberg,
Organometallics, 2010, 29, 2176–2179.
3
3
4
8
9
0
B. Huber and B. Roling, Electrochim. Acta, 2011, 56, 6569–
6572.
Bruker Instrument Service v3.0.26, APEX2 v2012.10-0,
SAINT v8.27B, Bruker AXS Inc., Madison, Wisconsin, USA.
M. C. Burla, R. Caliandro, B. Carrozzini, G. L. Cascarano, C.
Cuocci, C. Giacovazzo, M. Mallamo, A. Mazzone and G.
Polidori, J. Appl. Crystallogr., 2015, 48, 306–309.
G. M. Sheldrick, Acta Crystallogr. A, 2015, A71, 3–8.
A. L. Spek, Acta Crystallogr. D, 2009, 65, 148–155.
L. J. Farrugia, J. Appl. Crystallogr., 2012, 45, 849–854.
SADABS v2012/1, Bruker AXS Inc., Madison, Wisconsin,
USA.
41
42
43
44
45
Diamond - Crystal and Molecular Structure Visualization,
Crystal Impact
- H. Putz & K. Brandenburg GbR,
Kreuzherrenstr. 102, 53227 Bonn, Germany, 2009.
46
47
48
W. L. F. Armarego and D. D. Perrin, Purification of
Laboratory Chemicals, Elsevier, Burlington, 4th edn., 1996.
H. J. Kim, W. S. Lee, S. Won, and K. B. Park, WO
2007091817 A1, 2007.
M. Perseghini and A. Togni, in Science of Synthesis, ed. M.
Lautens, Georg Thieme Verlag, Stuttgart, New York, 2001,
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 9
Please do not adjust margins

Dalton Transactions
Page 10 of 10
View Article Online
DOI: 10.1039/C7DT04139J
8
0x36mm (300 x 300 DPI)