Hiyama coupling reaction of fluorous alkenyl-fluorosilanes: Scope and mechanistic considerations

Article abstract of DOI:10.1016/j.jfluchem.2012.03.007

Novel fluorous alkenyl-fluorosilanes (C_nF _2n+1CHCHSiMe₂F; n = 4, 6, 8; 5a-c) were synthetized in a three step procedure from perfluoroalkyliodides and dimethylvinylchlorosilane. They were first reacted with iodobenzene at room temperature in Hiyama coupling reaction (DMF, Pd(OAc)₂, TBAF, 72 h) to afford the appropriate ω-perfluoroalkyl-styrenes (C_nF_2n+1CHCHC ₆H₅, n = 4, 6, 8); then the reactivity of 5a with monosubstituted iodobenzenes was studied. The coupling reaction of 5a with o-substituted iodobenzenes usually failed, while that of with the m- and p-substituted ones gave fluorous styrenes [m- or p-(C₄F ₉CHCH)C₆H₄X], independently of the electronic effect of their substituent (X = Br, CF₃, CH₃, OCH ₃). These volatile products can easily be isolated by steam-distilltaion and purified further by distillation. The mechanism of the above coupling reactions was a pure Hiyama type involving fluoride-ion induced transmetallation without any Heck type contribution, since no coupling product of C₆F₁₃CHCH₂ and C₆H₅I was observed in blank control experiments using similar conditions (DMF, TBAF, Pd(OAc)₂, 72 h, 25°C).

Full text of DOI:10.1016/j.jfluchem.2012.03.007

Journal of Fluorine Chemistry 137 (2012) 85–92
Contents lists available at SciVerse ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Hiyama coupling reaction of fluorous alkenyl-fluorosilanes:
Scope and mechanistic considerations
´
*
´
´
´
Agnes Csapo, Andrea Bodor, Jozsef Rabai
´
Institute of Chemistry, Eo¨tvo¨s Lorand University, P.O. Box 32, H-1518, Budapest 112, Hungary
A R T I C L E I N F O
A B S T R A C T
Article history:
Novel fluorous alkenyl-fluorosilanes (CnF2n+1CH55CHSiMe2F; n = 4, 6, 8; 5a–c) were synthetized in a three
step procedure from perfluoroalkyliodides and dimethylvinylchlorosilane. They were first reacted with
iodobenzene at room temperature in Hiyama coupling reaction (DMF, Pd(OAc)2, TBAF, 72 h) to afford the
Received 21 December 2011
Received in revised form 2 March 2012
Accepted 5 March 2012
appropriate
v-perfluoroalkyl-styrenes (CnF2n+1CH55CHC6H5, n = 4, 6, 8); then the reactivity of 5a with
Available online 13 March 2012
monosubstituted iodobenzenes was studied. The coupling reaction of 5a with o-substituted
iodobenzenes usually failed, while that of with the m- and p-substituted ones gave fluorous styrenes
[m- or p-(C4F9CH55CH)C6H4X], independently of the electronic effect of their substituent (X = Br, CF3, CH3,
OCH3). These volatile products can easily be isolated by steam-distilltaion and purified further by
distillation.
Keywords:
Perfluoroalkylation at room temperature
Hiyama coupling
Fluorous styrenes
The mechanism of the above coupling reactions was a pure Hiyama type involving fluoride-ion
induced transmetallation without any Heck type contribution, since no coupling product of C6F13CH55CH2
and C6H5I was observed in blank control experiments using similar conditions (DMF, TBAF, Pd(OAc)2,
72 h, 25 8C).
Steam-distillation
ß 2012 Elsevier B.V. All rights reserved.
1. Introduction
The expansion of the scope of the Hiyama cross-coupling
reaction by the introduction of organosiletanes, -silanols, and -
The Hiyama cross-coupling reaction is an important palladium
catalyzed carbon–carbon bond formation reaction, where the
coupling of aryl and alkenyl-halogenides or -triflates with organo-
silanes constitutes its early examples [1]. The scope of this silicon-
based reaction is summarized below to disclose that a large variety
of organic groups bonded to silicon (R1) are suitable transferable
groups (TG55R1) (Scheme 1) [2].
Various organosilicon reagents are now commercially available
that are stable under normal conditions but can be activated to
provide the requisite TG’s. Moreover silicon is an environmentally
benign element, since organosilicon compounds are ultimately
oxidized to biologically inactive silica gel. Since the Si–C bond is
quite stable, it has to be polarized for the success of the Hiyama-
coupling. The activation of the silicon compound (R1–SiY3) by
siloxanes, was executed in the last decades by Denmark [7], and
others [8]. The fluoride-free activation of silanolates accessable
from the base treatment of the latter silicon compounds allowed
the simultanous use of silyl-protected substrates which are
necessary for natural products synthesis. Thus the latter variant,
the Hiyama-Denmark coupling reaction [9] is considered as a
practical alternative to the boron- and tin-based cross-coupling
reactions [10].
Recent improvements of this coupling reaction allow the use of
milder conditions with good functional group tolerance. Lee and Fu
developed the first method for the Hiyama coupling of unactivated
alkyl bromides and iodides [11]. Sarkar and others introduced Pd
nanoparticles for the coupling of arylsiloxanes with benzyl halides
[12].
´
fluoride ions involves the formation of
a
pentacoordinated
Novak and coworkers disclosed that Pd/C catalysts could also be
siliconate, which then initiates the transmetallation step. The
reactivity of the silanes (R1–SiY3) can be increased if the spectator
methyl ligands at (R1–SiMe3) are substituted for alkoxides [3],
chlorines [3], fluorines [3,4], or for heterocycles, like the 2-pyridyl-
group [5] and the 2-thienyl-group (Scheme 2) [6].
applied effectively in Hiyama and other cross-coupling reactions
but their activity is dependent on the kind of support and their
processing method [13].
However, fluorous-alkenyl fluorosilanes (RfnCH55CHSiMe2F;
n = 4, 6, 8) are unknown in the literature and not tested yet for
Hiyama cross-coupling reaction as (perfluoroalkyl)-alkenyl-TG
precursors. Only a recent article reports on the use of some light
fluorous-tagged alkenylgermanes in a palladium-catalyzed reac-
tion with aryl-bromides [14].
* Corresponding author. Tel.: +36 1 372 2500; fax: +36 1 372 2620.
E-mail address: rabai@elte.hu (J. Ra´bai).
0022-1139/$ – see front matter ß 2012 Elsevier B.V. All rights reserved.
doi:10.1016/j.jfluchem.2012.03.007

´
A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
86
Pd cat
R1 SiY3
[(CH255CHSiMe2)O] was accompanied by the regioselective addi-
R1---R2
+
R2
X
tion of perfluoroalkyl-iodides (2), initiated with AIBN, to afford
fluorous diiodo-disiloxanes (3) (Scheme 4; and Section 4, GP-1).
This reaction with longer perfluoroalkyl-iodides gave good yields
at 80 8C, but in the case of C4F9I the yield decreased. It can be
caused by the lower boiling point of C4F9I. When the latter reaction
was performed at 70 8C with longer time the yield increased as
expected. The synergic effect of aqueous K2S2O5 solution on the
AIBN initiated additions of perfluoro alkyliodides has already been
discussed [17], and exploited for the synthesis of fluorous
iodohydrines [18].
activator
R1
R2
=
alkynyl, alkenyl, aryl, alkyl, silyl
alkenyl, aryl, allyl
=
X =
Cl, Br, I, OTf, OCO2Et
SiY3 = SiMe3, Si(OR3), SiMe2OH, SiMe2F, SiMeF2, SiF3,
Pd cat: (η3C3H5PdCl)2, Pd(PPh3)4, Pd(OAc)2, Pd-nanoparticle
Activator: TBAF, TASF, KF, base
Scheme 1. The scope and the requisite catalysts and activators of the Hiyama
The 1H NMR and the 13C NMR spectra of compounds 3 showed
some unexpected features as compared to the previously described
assignments by Beyou and co-workers [19].
coupling reaction.
Our aim was to develop an easy access to fluorous-alkenyl
fluorosilanes (R1–SiY3: RfnCH55CHSiMe2F; Schemes 1 and 2) starting
from perfluoroalkyl iodides, then to study their suitability for using
as perfluoroalkylalkenyl-group transfer reagents under Hiyama
cross-coupling conditions with aryl iodides. This study could also
result in the addition of novel protocols for the synthesis of
fluorous compounds [15].
We also aimed at devising reaction condition that ensure that
the formation of our model fluorous styrenes proceeds with a clear
transmetallation step, without any percent contribution of a Heck
type pathway (Scheme 3) [16].
For example, in the 1H NMR (700 MHz) spectra of 3a, four
distinct signals with the same intensity appear in the highly
shielded methyl region at 0.6 ppm, and the corresponding 13C NMR
signals appear as two groups at À1.39 ppm and À1.41 ppm, and
two overlapping signals at À1.86 ppm, respectively (Scheme 5).
This pattern could be interpreted on the one hand that the
molecule is not symmetric (alike to compounds 4 and 5), and this
asymmetry is due to the presence of the steric effect of the iodine
atom, and also to the chirality centers at the C carbons. On the
a
other hand the two methine-carbons (–*CHI–) are also not
equivalent but highly shielded; see the very low 13C chemical
shift at À0.18 ppm and broad signal with a line width of 4.7 Hz,
compared to the 1.0 Hz line width of the methyl carbons.
The corresponding 1H resonances show a multiplet structure.
The broadening effect is detected also on the adjacent CH2 carbons
that has a multiplet splitting due to the 3JCF coupling (cf. Section 4).
The two H atoms are not equivalent as shown on their 1H spectra
(cf. Supplementary material).
2. Results and discussion
We disclose here new and optimized procedures for the
preparation of fluorous organosilicon compounds which can be
used effectively in Hiyama coupling reaction. The in situ hydrolysis
of dimethylvinylchlorosilane (1) to tetramethyldivinyldisiloxane
R1–R2
R2–X
L2Pd
reductive
elimination
oxidative addition
L
L
R2
R2
Pd L
R1
Pd X
L
Y
Y
Y
Y3Si–R1 + Bu4NF
Si
F
R1 NBu4
transmetalation
trans-cis
L
isomerisation
Pd R1
L
R2
Y
Y
Si
F
X
NBu4
Y
Scheme 2. A simplified mechanism for the Hiyama coupling reaction.
Scheme 3. Two simplified pathways to
v-perfluoroalkyl-styrenes in a fluorous Hiyama coupling reaction. Upper path: clear Hiyama mechanism, lower path: coupling with
Heck mechanism.

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A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
87
I
I
2 R I (2), AIBN
HNEt
o
fn
2
Rfn
Rfn
Rfn
Rfn
Si Cl
(E)
2
(E)
Si O Si
Si O Si
H O, K S O
2 2 5
80 C
2
(1)
(3)
(4)
2, 3, 4, 5, and 7: R = n-C F (a), n-C F (b), and n-C F (c)
fn
4
9
6
13
8
17
ArI (6), Pd(OAc)
BF OEt
3
2
2
Rfn
Rfn
(E)
Si F
Ar
(E)
o
+
-
100 C
NBu F , NEt , DMF
4
3
(7)
(5)
7a-c: Ar = Ph; 7d-q: R = n-C F , Ar = XC H , X = m-CF (e), p-CF (f), m-OCH (h), p-OCH (i), o-CH (n), p-CH (o),
fn
4
9
6
4
3
3
3
3
3
3
p-Br (p), 1-C H (q) yields: 17-91%; while X = o-CF (d), o-OCH (g), o-Cl (j), o-Br (k), o-NH (l), o-NHAc (m), yields: 0 %
10
7
3
3
2
Scheme 4. Synthesis of (polyfluoroalkenyl)-fluorosilanes (5) and their coupling with iodobenzenes (6).
The dehydro-halogenation of 3 with HNEt2 results in the
formation of the appropriate fluorous alkenyl-disiloxanes (4). This
reaction can be completed with other organic bases as well. We
chose diethyl-amine because it can be easy separated from the
reaction mixture and to a literature precedent (Scheme 5; Section
4, GP-2) [20].
However, dehydrohalogenation has a simplifying effect on the
NMR spectra, because the disappearance of the chirality centers
leads to one resonance for all the methyl groups of disiloxanes 4.
In the next step disiloxanes 4 are effectively converted to
fluorous alkenyl-fluorosilanes (5) by heating them with borontri-
fluoride-ether at 100 8C without any solvents (Section 4; GP-3)
[21].
Due to the formation of a new Si–F bond in 5, new couplings
appear in their NMR spectra. The 1H NMR sign of Si–CH become a
ddt (doublet–doublet–triplet), while both CF2–CH and Si–CH
carbons show a dt (doublet–triplet) in their 13C NMR. The Si–CH3
become also a doublet in 13C NMR because of the Si–F bond
(3JCF = 15 Hz).
Alkenyl-fluorosilanes are good candidates for Hiyama coupling
reactions. We tried to apply these fluorosilane-derivatives as
coupling reagents with halobenzenes. The first exercise was to
choose the appropriate reaction conditions. Since iodobenzenes
are the most reactive partners in the Pd-catalyzed reactions our
experiments are centered on the coupling of these compounds. The
efficiency of various Pd catalysts (4 mol% catalyst) was tested on
the reaction of iodobenzene and (perfluorobutylvinyl)-dimethyl-
fluorosilane (Scheme 6 and Table 1).
lowest unit price. It should be noted that Pd/C and Pd(PPh3)4 were
found inactive under the mild experimental conditions used (cf.
Section 4).
During the setting of the experimental conditions we observed
that the Si–C bond of these alkenyl-silanes can be cleaved at higher
temperatures with the activator TBAF. Thus we heated a solution of
1,3-divinyltetramethyl-disiloxane and TBAF in DMF for 1 h at 90 8C
in a closed Pyrex pressure tube. Then the headspace of the pressure
tube was sampled and analyzed by GC–MS to indicate that it
contains approximately 90% of ethene (Scheme 7).
We also found that the silicon–carbon bond in fluorous
alkenylfluorosilanes 5 could be cleaved by TBAF at elevated
temperatures. Thus a protodesilylation reaction of fluorosilane 5a
(Rf455C4F9) with excess TBAF in DMF at 90 8C gave the correspond-
ing fluorous olefin in 90% yield (Scheme 8).
These are qualitative evidences of our theory that the fluoride
source might cleave the Si–C bonds in some alkenylsilanes at
elevated temperatures and thus it could generate in situ the
appropriate olefins [22]. These olefins then may couple in a Heck
type mechanism with iodobenzenes to afford the same products as
if they were reacted with a pure Hiyama type coupling mechanism.
This observation made it clear that the coupling reaction of some
After comparing the results of the five commercial Pd catalysts,
Pd(OAc)2 was selected for further studies, since it gave the purest
isolated product within an acceptable reaction time and with the
Scheme 6. Model reaction for testing catalysts efficiency (cf. Table 1).
Table 1
Efficiency of Pd-catalysts on the formation and purity of
v
-perfluorobutyl-styrene
at 20 8C in DMF.
Entry
Catalysta
(4 mol%)
Conversion 100%
Isolated
yield
Purity
of 7a
of 6a after
Conversion
20 h (%)
of 6a (day(s))
of 7a (%)
(GC %)
1
2
3
4
5
10% Pd/C
0
0
–
–
3
1
1
–
–
–
–
Pd(PPh3)4
Pd(OAc)2
15
99.5
92
60%
47%
60%
90%
83%
72%
Pd2dba3
[(h3-allyl)PdCl]2
a
Entries 1–2 and 3–5 are heterogeneous or homogeneous systems at 0.025 mmol
catalyst/1.0 ml DMF loading, respectively.
Scheme 5. Part of 1H–13C HSQC spectra of 3a at 700 MHz.

´
A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
88
Scheme 7. The reaction of a vinylsiloxane with TBAF at higher temperature.
Scheme 9. Blank experiment to exclude the possibility of Heck type contribution.
Scheme 8. The reaction of a fluorous alkenylfluorosilane (5a) with TBAF at higher
temperature.
Scheme 10. HRMS evidence for the formation of a fluorous pentacoordinated
silicate [5a+FÀ]. Calculated mass [M+F]À = 341.0225, measured mass
[M+F]À = 341.0224, mass difference: À0.2 ppm.
structural type organosilanes at higher temperature not necessar-
ily follow a pure Hiyama type mechanism, which involves a
transmetallation step through a pentacoordinate silicate-anion.
First the reaction of fluorosilanes 5a–c and iodobenzene 6a was
investigated (Table 2, Entries 1–3) to reveal the effect of the length
of fluorous-chains on product 7a–c yields. However, no significant
effect was observed. Some alternative methods for the synthesis
fluorous styrenes 7a–c are known in the literature [15e,f,23–26].
We tried to apply substituted iodobenzenes as coupling
reagents as well. First, a series of CF3- (6d–f) and CH3O-substituted
(6g–i) iodobenzenes were tested (Table 2, Entries 4–9). Both series
show the same results, the yields increase in the ortho, meta, para
direction, independently of the electronic effect of the substituent.
These results may suggest, that the reaction of the halobenzene is
controlled by steric factors.
To collect more evidences some other ortho substituted
iodobenzenes were tested (Table 2, Entries 10–14). The selected
substituents represent different sizes and electronic effects. With
ortho-Cl-(6j) and ortho-Br-(6k) derivatives the formation of 7j and
7k was detected with 1H NMR, via a typical doublet–triplet sign at
ꢀ6 ppm, but their isolation was not performed because of their
trace amounts. With ortho-NH2-(6l) and ortho-NHAc-(6m) deri-
vatives no formation of the appropriate styrenes was observed at
all. Only exception is ortho-iodotoluene (6n), which allowed the
isolation of styrene 7n in 17% with 90% purity (GC assay).
Then the reaction of some other para-substituted iodobenzenes
– 4-iodotoluene (6o) and 4-iodobromo-benzene (6p) – was studied
A
blank experiment was also performed to exclude the
possibility of a Heck type mechanism in our room temperature
Hiyama coupling protocol (Scheme 9). Here we kept all conditions
unchanged, but substituted perfluorohexylethene (Rf6CH55CH2) for
(perfluorohexylethenyl)-dimethylfluorosilane (Rf6CH55CHSiMe2F,
5b). There was no formation of fluorous styrene in this control
experiment during one week stirring at room temperature, but 90%
of the starting iodobenzene was recovered in 98% chemical purity
(GC).
Consequently we choose room temperature for our further
experiments with the above fluorous alkenyl-fluorosilanes to be
able to scope the nature of the Hiyama coupling reaction without
any Heck type contributions (cf. Scheme 3). We performed an
HPLC–TOF MS measurement to determine the exact mass of the
complex formed by the reaction of 5a and TBAF. The result
obtained was agreeable with the formation of a pentacoordinated
silicate-anion; a possible intermediate of transmetallation accord-
ing to Hiyama and co-workers (Scheme 10).
Then we studied the Hiyama coupling of selected alkenyl-
fluorosilanes (5) and iodobenzenes (6) in DMF solution using
Pd(OAc)2 as precatalyst and TBAF as an activator at room
temperature (Table 2; Section 4, GP-4). Different fluorosilanes
and iodoarenes were used to learn the reaction scope.
Table 2
Reaction of fluorosilanes (5) with aryl iodides (6) under ‘room temperature Hiyama coupling’ conditions.
Entry
Ar-
Rfn
(E)-RfnCH5CHAr (7)
Yield (%)a
Purity (%)b
Lit. datac (bp 8C/kPa)
(mp 8C/solvent
)
1
2
C6H5 (6a = 6b =6c)
C6H5 (6a = 6b =6c)
C6H5 (6a = 6b = 6c)
o-CF3–C6H4 (6d)
m-CF3–C6H4 (6e)
p-CF3–C6H4 (6f)
o-CH3O–C6H4 (6g)
m-CH3O–C6H4 (6h)
p-CH3O–C6H4 (6i)
o-Cl–C6H4 (6j)
n-C4F9
n-C6F13
n-C8F17
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
n-C4F9
7a colorless oil
7b colorless oil
7c colorless oil
7d –
61
63
50
0d
35
47
0d
11
56
0d
0d
0d
0d
17
91
25
51
91
95
90
–
bp = 76–78/3.1 [27]
mp = 38–39.5/hexane [28]
3
mp = 59–61/hexane [28]
4
–
5
7e colorless oil
7f colorless oil
7g –
82
78
–
n. c.
n. c.
–
6
7
8
7h colorless oil
7i colorless oil
7j –
91
98
–
n. c.
n. c.
–
9
10
11
12
13
14
15
16
17
o-Br–C6H4 (6k)
7k –
–
–
o-H2N–C6H4 (6l)
o-AcNH–C6H4 (6m)
o-CH3–C6H4 (6n)
p-CH3–C6H4 (6o)
p-Br–C6H4 (6p)
7l –
–
–
7m –
–
–
7n colorless oil
7o colorless oil
7p colorless oil
7q yellow oil
90
93
90
94
n. c.
n. c.
n. c.
n. c.
1-C10H7 (6q)
a
Isolated yield.
b
c
Determined by GC.
n. c., new compound.
d
Unchanged aryl iodide was recovered.

´
A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
89
(Table 2, Entries 15–16). Here, the coupling reaction takes place in
the presence of both electron withdrawing and electron donating
groups in para position. These results show clearly, that the
reaction is controlled mostly by steric factors among others. Finally
the reaction of 1-iodonaphtalene (6q) was tested. The expected
fluorous naphthalene derivative (7q) was isolated in good yield
and purity.
All the new compounds including fluorous fluorosilanes and -
styrenes were characterized by 1H, 13C and 19F NMR spectra, and
their purity assayed by GC analysis (cf. Section 4). The fluorous
styrenes shown above are liquids or low melting solids, volatile
with steam and easily soluble in common organic solvents (e.g.,
ether, acetone, benzene, ethyl acetate, dichloromethane and
chloroform).
or Pd2dba3; or 28.6 mg (0.0247 mmol, 0.0247 mmol Pd atom) of
Pd(PPh3)4] was stirred at room temperature inanargon atmosphere.
The reactions were monitored with GC. After the reaction completed
the mixture was diluted with 50 ml of water and distilled. The
distillate was extracted with diethyl ether, dried (Na2SO4) and the
solvent was removed in vacuo.
Yields of 7a: 0 mg (0%) for 10%Pd/C and 0 mg (0%) for Pd(PPh3)4;
120 mg (60%) (GC assay: 90%) for Pd(OAc)2; 95 mg (47%) (GC assay:
83%) for Pd2dba3; and 120 mg (60%) (GC assay: 72%) for (h3-allyl-
PdCl)2.
4.2.2. Formation of 3,3,4,4,5,5,6,6,6-nonafluorohex-1-ene by TBAF
cleavage of fluorosilane 5a
A round bottomed flask was charged with Rf4CH55CHSiMe2F
(3.22 g, 10 mmol), TBAFÁ3H2O (4.73 g, 15 mmol) and DMF (10 ml),
then it was set for distillation. The mixture was stirred and heated at
80–90 8C until all the generated F-olefin (Rf4–CH55CH2) distilled.
Yield: 2.20 g (89.4%) colorless oil, bp = 59–60 8C/1 atm (GC assay:
98%).
3. Conclusions
A simple route for the synthesis of novel fluorous alkenyl
fluorosilanes was developed and these products were used as the
source of transferable groups for a fluorous Hiyama-reaction.
Experimental evidence was given that the fluoride activators
used in the Hiyama cross-coupling reaction at higher temperatures
could initiate the protodesilylation reaction of the silicon substrate
to afford fluorous alkenes [29].
4.2.3. Cross-coupling experiment of Rf6CH55CH2 and C6H5I
A mixture of iodobenzene (0.48 g, 2.37 mmol), perfluorohexyl-
ethene (0.82 g, 2.37 mmol), TBAFÁ3H2O (1.50 g; 4.74 mmol),
Pd(OAc)2 (0.021 g, 4 mol%) and 3.0 ml DMF was stirred at room
temperature for 7 days under an argon atmosphere. Then the
reaction mixture was partitioned between water (30 ml) and ether
(30 ml). The aqueous phase was washed with ether (3Â 10 ml), and
then the combined ethereal extracts were washed with water (3Â
10 ml). The ether layer was separated, dried (Na2SO4) and the
solvent was removed by distillation. The residual oil (1.2 g) was
analyzed by GC, which indicated the presence of iodobenzene and
perfluorohexyl-ethene as main components, but no peak for the
Iodoarenes were coupled effectively with fluorous alkenyl-
fluorosilanes yielding
v-perfluoroalkyl-styrenes under conditions
where the formation of terminal fluorous alkenes could be
definitely excluded.
4. Experimental
4.1. Materials and methods
formation of the corresponding
detected. Short path distillation allowed the recovery of 0.43 g
(90%) iodobenzene (GC assay: 98%).
v-perfluorohexylstyrene was
Catalysts Pd2dba3 and Pd(OAc)2 (99.9+%), 10%Pd/C [(h3
-
allyl)PdCl]2, and Pd(PPh3)4 were purchased from Aldrich, Merck,
Strem and Alfa Aesar, respectively. The other reagents and solvents
were purchased from Alfa Aesar or Molar, but 6m prepared from 6l
as reported [30]. DMF was distilled from CaH2 prior to use. NMR
spectra were recorded at 298 K on Bruker Avance 250 MHz and
4.3. Reaction of 1,3-divinyltetramethyldisiloxane with TBAF
1,3-Divinyltetramethyldisiloxane
(0.46 g,
2.5 mmol),
Avance III 700 MHz spectrometers equipped with
a
QNP
TBAFÁ3H2O (3.15 g, 10 mmol) and DMF (5.0 ml) was stirred under
an argon atmosphere in a closed tube at 80 8C for 1.5 h. The mixture
was cooled to room temperature. The head-space gas formed was
1H/13C/19F/31P and a triple-resonance z-axis pulsed field gradient
probe-head, respectively. 1H and 13C spectra were referenced to
the signal of chloroform. Standard Bruker pulse sequences were
run, spectra analysis was performed with TopSpin. Chemical shifts
passed into
a sample tube and analyzed by GC–MS. The
measurement showed 90% ethylene (cf. Supplementary).
(
d
) are given in parts per million (ppm) units relatively to the
internal standard TMS (
= 0.00 for 1H, = 0.00 for 13C) and to CFCl3
as external standard (
= 0.00 for 19F). HPLC-TOF analysis was
d
d
d
4.4. Preparation of 1,3-bis(1-iodo-2-perfluoroalkyl-ethyl)-
tetramethyldisiloxanes (3a–c); general procedure 1 (GP-1)
performed on an Agilent 1200 series HPLC coupled to an Agilent
6210 Time of Flight mass spectrometer. Dual ESI ion source was
operated in negative mode. GCMS SHS measurement was
performed on an Agilent 7890A chromatograph coupled to an
Agilent 5975C inert XL mass spectrometer. GC analyses were
performed on a Hewlett-Packard 5890 Series II chromatograph,
A 250 ml round-bottomed two-necked flask was provided with
a magnetic stirrer bar, equipped with a thermometer and a
condenser. Dimethylvinylchlorosilane (1) (5.00 g; 41.4 mmol),
perfluoroalkyl-iodide (2a–c) and the aqueous solution of K2S2O5
(3.20 g, 14.4 mmol salt in 10 ml water) was placed in the flask. The
mixture was stirred and heated to 70 or 80 8C and AIBN (0.50 g,
3.0 mmol) was added in small portions during 1.5–2.5 h. The
mixture was further stirred on 70 or 80 8C for 4 h. After cooling the
mixture to r.t. it was partitioned between water and ether. The
aqueous phase was washed with ether, than the collected ethereal
phase was washed with water 3 times. The organic layer was
separated, dried (Na2SO4) and compound 3 was isolated by
fractional vacuum-distillation.
Column:
PONA
[crosslinked
methylsilicone
gum],
50 m  0.2 mm  0.5
mm, carrier gas: H2, FID detection (detector:
280 8C). Temperature program: 120, 5, 10, 280, 10. Injector: 250 8C.
4.2. Development of room temperature cross-coupling protocol
4.2.1. Catalyst-testing – the model reaction
A mixture of Rf4CH55CHSiMe2F (5a, 0.20 g, 0.62 mmol), iodo-
benzene (6a, 0.13 g, 0.62 mmol), TBAFÁ3H2O (0.39 g, 1.24 mmol),
1.00 ml DMF and 4.0 mol% Pd-catalyst [5.60 mg (0.0249 mmol,
0.0249 mmol Pd atom) of Pd(OAc)2; 26.4 mg (0.0248 mmol Pd
atom) of 10%Pd/C; 9.10 mg (0.0248 mmol, 0.0496 mmol Pd atom) of
4.4.1. 1,3-Bis(1-Iodo-3,3,4,4,5,5,6,6-nonafluoro-hexan-1-yl)-
tetramethyldisiloxane; (Rf4CH2CH(I)SiMe2)2O (3a)
The reaction was performed according to GP-1 using 2a
(21.59 g; 62.4 mmol). The reaction temperature was 70 8C, AIBN
(
h3-allyl-PdCl)2; 22.7 mg (0.0247 mmol, 0.0494 mmol Pd atom) of

´
A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
90
addition: 2.5 h. Yield: 15.28 g (84.0%) light-purple oil.
Bath temperature = 140–150 8C/13 Pa. Fw: 878.22 g/mol; calcu-
lated iodine%: 28.9%; found iodine%: 28.19%; purity: 97.5%
(microanalytical iodine%).
1H NMR (CDCl3):
d
= 0.21 (s; 12H, Si–CH3); 6.06 (dt;
3
3
3JHH = 19 Hz, JHF = 11 Hz, 2H, CF2–CH); 6.60 (dt; JHH = 19.0 Hz;
4JHF = 2.3 Hz; 2H, Si–CH). 13C NMR (CDCl3):
d = 0.21 (s; Si–CH3);
3
4
131.3 (t; JCF = 24 Hz; CF2–CH); 141.9 (t; JCF = 6 Hz; Si–CH). 19F
3
1H NMR (CDCl3; 700 MHz):
d
= 0.332 (s, 3H, CH3), 0.340 (s, 3H,
NMR (CDCl3):
À125.1 (m; 2F); À126.4 (m; 2F).
d
= À81.71 (t; JFF = 10.5 Hz; 3F); À114.53 (m; 2F);
CH3), 0.341 (s, 3H, CH3), 0.348 (s, 3H, CH3); 2.500–2.600 (m; 2H,
CH2); 2.750–2.850 (m; 2H, CH2), 3.150–3.180 (m; 2H, two CH). (cf.
Supplementary) 13C NMR (CDCl3; 700 MHz):
d
= À1.86 (s, two
4.5.2. 1,3-Bis(3,3,4,4,5,5,6,6,6,7,7,8,8,8-tridecafluoro-octen-1-yl)-
tetramethyldisiloxane (Rf6CH55CHSiMe2)2O (4b)
overlapping CH3), À1.41 (s, CH3), À1.39 (s, CH3), À0.18 (s, broad
2
signal of CH-s), 34.5 (t, JCF = 21.5 Hz, broad signal of CH2-s). 19F
The reaction was performed according to GP-2 using 3b (5.00 g;
4.64 mmol), and HNEt2 (1.1 g, 15 mmol). Yield: 2.90 g (76.0%)
colorless oil. Bath temperature = 170 8C/ꢀ2.3 kPa. GC assay: 92%.
NMR (CDCl3; 250 MHz):
(m; 2F); À125.2 (m; 2F); À126.51 (m; 2F).
d
= À81.62 (t; 3JFF = 10.5 Hz; 3F);À115.62
1H NMR (CDCl3):
d = 0.21 (s; 12H, Si–CH3); 6.06 (dt;
3
3
4.4.2. 1,3-Bis(1-Iodo-3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octan-1-
yl)-tetramethyldisiloxane; (Rf6CH2CH(I)SiMe2)2O (3b)
3JHH = 19 Hz, JHF = 11 Hz, 2H, CF2–CH); 6.60 (dt; JHH = 19.0 Hz;
4JHF = 2.3 Hz; 2H, Si–CH). 13C NMR (CDCl3):
d = 0.21 (s; Si–CH3);
3
4
The reaction was performed according to GP-1 using 2b
(27.82 g; 62.4 mmol). The reaction temperature was 80 8C, AIBN
addition: 1.5 h. Yield: 19.35 g (86.7%) light-purple oil. Bath
temperature = 170–180 8C/13 Pa. Fw: 1078.22 g/mol; calculated
iodine%: 23.54%, found iodine%: 23.24%; purity: 98.7% (microana-
lytical iodine%).
131.3 (t; JCF = 24 Hz; CF2–CH); 141.9 (t; JCF = 6 Hz; Si–CH). 19F
3
NMR (CDCl3):
d
= À81.6 (t; JFF = 10.5 Hz; 3F); À114.3 (m; 2F);
À122.3 (m; 2F); À123.6 (m; 2F); À124.1 (m; 2F); À126.8 (m; 2F).
4.5.3. 1,3-Bis(3,3,4,4,5,5,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-
decen-1-yl)-tetramethyldisiloxane (Rf8CH55CHSiMe2)2O (4c)
The reaction was performed according to GP-2 using 3c (10.0 g;
7.82 mmol), and HNEt2 (2.0 g, 27.4 mmol). Yield: 6.86 g (85.75%)
colorless oil. Bath temperature = 190 8C/ꢀ2.3 kPa. GC assay: 88%.
1H NMR (CDCl3):
d = 0.32 (s, 3H, CH3), 0.33 (s, 6H, two
overlapping CH3), 0.34 (s, 3H, CH3), 2.40–2.65 (m; 2H, CH2);
2.65–2.95 (m; 2H, CH2), 3.10–3.20 (m; 2H, two CH). 13C NMR
(CDCl3):
d
= À1.63 (m; two overlapping CH3); À1.13 (m, two
1H NMR (CDCl3):
d
= 0.21 (s; 12H, Si–CH3); 6.06 (dt;
3
3
overlapping CH3), 0.08 (s, broad signal of CH-s), 34.77
(t, 2JCF = 21.5 Hz, broad signal of CH2-s). 19F NMR
(CDCl3):
3JHH = 19 Hz, JHF = 11 Hz, 2H, CF2–CH); 6.60 (dt; JHH = 19.0 Hz;
4JHF = 2.3 Hz; 2H, Si–CH). 13C NMR (CDCl3):
d = 0.21 (s; Si–CH3);
3
3
4
d
= À81.42 (t; JFF = 10.5 Hz; 3F); À115.35 (m; 2F);
131.3 (t; JCF = 24 Hz; CF2–CH); 141.9 (t; JCF = 6 Hz; Si–CH). 19F
3
À122.4 (m; 2F); À123.45 (m; 2F); À124.2 (m; 2F); À126.75 (m;
NMR (CDCl3):
d
= À81.56 (t; JFF = 10.5 Hz; 3F); À114.56 (m; 2F);
2F).
À122.3 (m; 2F); À122.8 (m; 6F); À123.6 (m; 2F); À127.1 (m; 2F).
4.4.3. 1,3-Bis(1-Iodo-3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-
heptadecafluoro-decan-1-yl)-tetramethyldisiloxane;
(Rf8CH2CH(I)SiMe2)2O (3c)
4.6. Preparation of dimethyl-(2-perfluoroalkyl-ethen-1-yl)-
fluorosilanes (5a–c); general procedure 3 (GP-3)
The reaction was performed according to GP-1 using 2c
(34.00 g; 62.4 mmol). The reaction temperature was 80 8C, AIBN
addition: 1.5 h. Yield: 21.80 g (82.4%) light-purple oil. Bath
temperature = 190–200 8C/13 Pa. Fw: 1278.34 g/mol; calculated
iodine%: 19.86%; found iodine%: 20.98%; purity: 94.6% (microana-
lytical iodine%).
d = 0.32 (s, 3H, CH3), 0.33 (s, 6H, two
overlapping CH3), 0.34 (s, 3H, CH3), 2.40–2.65 (m; 2H, CH2);
2.65–2.95 (m; 2H, CH2), 3.10–3.20 (m; 2H, two CH). 13C NMR
A 100 ml round-bottomed flask was provided with a magnetic
stirrer bar and equipped with a condenser. The alkenyl-disiloxane
(4a–c) and BF3ÁOEt2 was placed in the flask and the mixture was
stirred on 100 8C bath for 5 h. After cooling to r.t. the mixture was
partitioned between water and ether, the aqueous phase was
washed with ether, than the collected ethereal phase was washed
with water 3 times. The organic layer was separated, dried
(Na2SO4), than ether was removed by atmospheric distillation.
Compound 5 was isolated by fractional distillation.
1H NMR (CDCl3):
(CDCl3):
d
= À1.68 (m; two overlapping CH3); À1.17 (m, two
overlapping CH3), 0.05 (s, broad signal of CH-s), 34.8 (t,
2JCF = 21.5 Hz, broad signal of CH2-s). 19F NMR (CDCl3):
4.6.1. Dimethyl-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-
fluorosilane (5a)
3
d
= À81.59 (t; JFF = 10.5 Hz; 3F); À115.5 (m; 2F); À122.5 (m;
The reaction was performed according to GP-3 using disiloxane
4a (4.00 g; 6.43 mmol), and BF3OEt2 (2.3 g, 16.21 mmol). Yield:
2.95 g (71.25%) colorless oil. Bath temperature = 140–145 8C/
101.3 kPa. GC assay: 97%.
6F); À123.5 (m; 2F); À124.3 (m; 2F); À126.9 (m; 2F).
4.5. Preparation of 1,3-bis(2-perfluoroalkyl-ethen-1-yl)-
tetramethyldisiloxanes (4a–c); general procedure 2 (GP-2)
1H NMR (CDCl3):
d
= 0.36 (d; 3JHF = 7.3 Hz; 6H, Si–CH3); 6.21 (dt;
3
3
3JHH = 19 Hz, JHF = 11 Hz, 1H, CF2–CH); 6.64 (ddt; JHH = 19 Hz,
A mixture of the appropriate iodo-adduct 3 and diethylamine
was stirred and refluxed for 7 h with an ꢀ100 8C temperature oil
bath. Then the mixture was cooled to room temperature and the
excess of HNEt2 was evaporated (Rotavap). The residue obtained
was partitioned between water and ether. The ether extracts
were combined, washed with water and dried (Na2SO4), then
product 4 was isolated by fractional distillation.
3JHF = 5 Hz, 4JHF = 2.3 Hz, 1H, Si–CH). 13C NMR (CDCl3):
3JCF = 15 Hz; Si–CH3); 133.0 (td, 3JCF = 3.5, 2JCF = 24, CF2–CH), 138.8
d
= À1.3 (d;
(dt; 2JCF = 24 Hz, 3JCF = 6 Hz, Si–CH). 19F NMR (CDCl3):
d
= À81.67 (t;
3JFF = 10.5 Hz; 3F); À114.85 (m; 2F); À124.97 (m; 2F); À126.40 (m;
2F); À163.82 (m; 1F).
4.6.2. Dimethyl-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-octen-1-yl)-
fluorosilane (5b)
4.5.1. 1,3-Bis(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-
tetramethyldisiloxane (Rf4CH55CHSiMe2)2O (4a)
The reaction was performed according to GP-2 using 3a
(12.00 g, 13.66 mmol) and HNEt2 (3.24 g, 44.4 mmol). Yield:
7.15 g (84.1%) colorless oil. Bath temperature = 145–155 8C/
ꢀ2.3 kPa. GC assay: 90%.
The reaction was performed according to GP-3 using disiloxane
4b (14.0 g; 17.0 mmol), and BF3OEt2 (7.00 g, 49.3 mmol). Yield:
10.07 g (70.05%) colorless oil. Bath = 70–75 8C/ꢀ2.3 kPa. GC assay:
96%.
1H NMR (CDCl3):
d
= 0.36 (d; 3JHF = 7.3 Hz; 6H, Si–CH3); 6.21 (dt;
3
3
3JHH = 19 Hz, JHF = 11 Hz, 1H, CF2–CH); 6.64 (ddt; JHH = 19 Hz,

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A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
91
3JHF = 5 Hz, 4JHF = 2.3 Hz, 1H, Si–CH). 13C NMR (CDCl3):
3JCF = 15 Hz; Si–CH3); 133.0 (td, 3JCF = 3.5, 2JCF = 24, CF2–CH), 138.8
d
= À1.3 (d;
4.7.3. (E)-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluoro-
decen-1-yl)-benzene (7c)
(dt; JCF = 24 Hz, JCF = 6 Hz, Si–CH). 19F NMR (CDCl3):
d
= À81.45
The reaction was performed according to GP-4 using fluor-
osilane 5c (1.24 g, 2.37 mmol) and iodobenzene 6c (0.48 g,
2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 1.5 ml of BTF and 1.5 ml of DMF for 3 days.
Yield: 0.62 g (50%) colorless oil. GC assay: 90%.
2
3
(t; 3JFF = 10.5 Hz; 3F); À114.60 (m; 2F); À122.25 (m; 2F); À123.51
(m; 2F); À124.0 (m; 2F); À126.79 (m; 2F); À163.81 (m; 1F).
4.6.3. Dimethyl-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-
decen-1-yl)-fluorosilane (5c)
3
3
1H NMR (CDCl3):
d = 6.19 (dt; JHH = 16 Hz, JHF = 12 Hz, 1H,
3
4
The reaction was performed according to GP-3 using disiloxane
4c (10.0 g; 9.78 mmol) and BF3OEt2 (4.2 g, 29.6 mmol). Yield:
7.50 g (73.4%) colorless oil. Bath temperature = 95–100 8C/
ꢀ2.3 kPa. GC assay: 96%.
CF2–CH); 7.17 (dt, JHH = 16 Hz, JHF = 2.3 Hz; 1H, Ar–CH); 7.3–7.6
(m; 5H, aromatic protons); 13C NMR (CDCl3):
d = 114.6 (t;
3JCF = 23 Hz; CH–CF2); 127.9 (s; CAr); 129.2 (s; CAr); 130.4 (s;
4
C
Ar); 133.8 (s; CAr,ipso), 140.0 (t; JCF = 10 Hz; Ar–CH55). 19F NMR
1H NMR (CDCl3):
d
= 0.36 (d; 3JHF = 7.3 Hz; 6H, Si–CH3); 6.21 (dt;
(CDCl3):
d
= À81.25 (t, 3JFF = 10.5 Hz, 3F), À111.56 (m; 2F), À121.86
3
3
3JHH = 19 Hz, JHF = 11 Hz, 1H, CF2–CH); 6.64 (ddt; JHH = 19 Hz,
(m; 2F), À122.38 (m; 4F), À123.19 (m; 2F), À123.66 (m; 2F),
À126.59 (m; 2F). In agreement with the published data [28].
3JHF = 5 Hz, 4JHF = 2.3 Hz, 1H, Si–CH). 13C NMR (CDCl3):
3JCF = 15 Hz; Si–CH3); 133.0 (td, 3JCF = 3.5, 2JCF = 24, CF2–CH), 138.8
(dt; 2JCF = 24 Hz, 3JCF = 6 Hz, Si–CH). 19F NMR (CDCl3):
d
= À1.3 (d;
d
= À81.42 (t;
4.7.4. (E)-1-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-3-
trifluoromethyl-benzene (7e)
3JFF = 10.5 Hz; 3F); À114.56 (m; 2F); À122.04 (m; 2F); À122.5 (m;
4F); À123.35 (m; 2F); À123.89 (m; 2F); À126.73 (m; 2F); À163.83
(m; 1F).
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6e (0.64 g,
2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 5 days. The product was
distilled in vacuo (bath: 120–125 8C/ꢀ2.3 kPa). Yield: 0.32 g (35%)
colorless oil. GC assay: 82%.
4.7. Hiyama coupling reactions with iodobenzene and its derivatives;
general procedure 4 (GP-4)
A mixture of the appropriate fluorosilanes (5a–c, 2.37 mmol)
and iodoarenes (6a–q, 2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol),
Pd(OAc)2 (0.021 g, 4 mol%) and DMF or DMF/BTF as solvent was
stirred at room temperature during 3–7 days in an argon
atmosphere. (Due to the lower miscibility of the Rf8-substituted
fluorosilane in DMF, that reaction must be done in DMF/BTF.) The
mixture was diluted with 100 ml water and steam-distilled. The
distillate was extracted with ether, the organic layer was
separated, dried (Na2SO4) and the solvent was removed under
vacuo (Rotavap). The product was purified with flash column
chromatography (silica 60, eluent: 100 ml n-hexan, column:
2.5 cm  6 cm).
1H NMR (CDCl3):
CH); 7.05–7.70 (m; 5H, Ar–CH overlaps with the aromatic protons).
13C NMR (CDCl3): = 116.6 (t, 2JCF = 24 Hz, CF2–CH); 124.6 (m; CAr);
d
= 6.2 (dt, 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
d
127.0 (m; CAr); 129.8 (s; CAr); 130.9 (s; CAr); 134.5 (s; CAr,ipso); 138.6
(t; 3JCF = 10 Hz, CH55CH–CF2), 19F NMR (CDCl3):
À81.59 (t; JFF = 10.5 Hz, 3F); À112.27 (m; 2F); À124.58 (m; 2F);
À126.27 (m; 2F).
d
= À63.5 (m; 3F);
3
4.7.5. (E)-1-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-4-
trifluoromethyl-benzene (7f)
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6f (0.64 g,
2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 5 days. Yield: 0.43 g (46.7%)
colorless oil. GC assay: 78%.
4.7.1. (E)-(3,3,4,4,5,5,6,6,6-Nonafluoro-hexen-1-yl)-benzene (7a)
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodobenzene 6a (0.48 g,
2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 3 days. Yield: 0.46 g (60.5%)
colorless oil. GC assay: 91%.
1H NMR (CDCl3):
CH); 7.15–7.7 (m; 5H, Ar–CH overlaps with the aromatic protons).
13C NMR (CDCl3): = 117.2 (t; 2JCF = 24 Hz; CH55CH–CF2); 126.2 (m;
d
= 6.28 (dt, 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
d
CAr); 128.1 (s; CAr); 137.0 (s; CAr,ipso); 138.6 (t; J = 10 Hz; CH55CH–
1H NMR (CDCl3):
CH); 7.17 (dt, 3JHH = 16 Hz, 4JHF = 2.3 Hz;1H, Ar–CH); 7.3–7.6 (m; 5H,
aromatic protons); 13C NMR (CDCl3): = 114.6 (t; 3JCF = 23 Hz; CH–
CF2); 127.5 (s; CAr); 128.9 (s; CAr); 130.4 (s; CAr); 133.8 (s; CAr,ipso),
d
= 6.19 (dt; 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
CF2). 19F NMR (CDCl3):
3F); À112.42 (m; 2F); À124.60 (m; 2F); À126.28 (m; 2F).
d
= À63.49 (s; 3F); À81.59 (t; 3JFF = 10.5 Hz,
d
4.7.6. (E)-1-Methoxy-3-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-
benzene (7h)
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6h (0.55 g,
2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 7 days. Yield: 0.10 g (10.5%)
4
140.0 (t; JCF = 10 Hz; Ar–CH = ). 19F NMR (CDCl3):
d
= À81.6 (t;
3JFF = 10.5 Hz, 3F); À111.8 (m; 2F); À124.6 (m; 2F); À126.2 (m; 2F).
In agreement with the published data [27].
4.7.2. (E)-(3,3,4,4,5,5,6,6,7,7,8,8,8-Tridecafluoro-octen-1-yl)-
benzene (7b)
colorless oil. GC assay: 91%.
3
The reaction was performed according to GP-4 using fluor-
osilane 5b (1.00 g, 2.37 mmol) and iodobenzene 6b (0.48 g,
2.37 mmol), TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 3 days. Yield: 0.63 g (63%)
colorless oil. GC assay: 95%.
1H NMR (CDCl3):
d
= 4.03 (s, 3H, OCH3) 6.35 (dt, JHH = 16 Hz,
3JHF = 12 Hz, 1H, CF2–CH); 7.1–7.55 (m; 5H, Ar–CH overlaps with
the aromatic protons). 13C NMR (CDCl3):
d = 55.52 (s, OCH3), 113.0
(s, CAr), 114.7 (t, 2JCF = 23 Hz, CF2–CH), 116.0 (s, CAr), 120.4 (s, CAr),
130.2 (s, CAr), 135.1 (s; CAr,ipso), 140.0 (t, JCF = 10 Hz, Ar–CH). 19F
3
1H NMR (CDCl3):
CH); 7.17 (dt, 3JHH = 16 Hz, 4JHF = 2.3 Hz;1H, Ar–CH); 7.3–7.6 (m; 5H,
aromatic protons); 13C NMR (CDCl3): = 114.6 (t; 3JCF = 23 Hz; CH–
CF2); 127.8 (s; CAr); 129.2 (s; CAr); 130.4 (s; CAr); 133.8 (s; CAr,ipso),
d
= 6.19 (dt; 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
NMR (CDCl3):
À124.6 (m; 2F), À126.2 (m; 2F).
d
= À81.55 (t, JFF = 10.5 Hz, 3F), À111.9 (m; 2F),
3
d
4.7.7. (E)-1-Methoxy-4-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-
benzene (7i)
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6i (0.55 g,
2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
4
140.0 (t; JCF = 10 Hz; Ar–CH). 19F NMR (CDCl3):
d
= À81.4 (t;
3JFF = 10.5 Hz, 3F); À111.7 (m; 2F); À122.2 (m; 2F); À123.4 (m; 2F);
À123.8 (m; 2F); À126.8 (m; 2F). In agreement with the published
data [28].

´
A. Csapo´ et al. / Journal of Fluorine Chemistry 137 (2012) 85–92
92
3
(0.021 g, 4 mol%) in 3 ml of DMF for 7 days. Yield: 0.47 g (56%)
(t; J = 10 Hz; CH55CH–CF2). 19F NMR:
d = 81.43 (t; JFF = 10.5 Hz,
colorless oil. GC assay: 98%.
3F); À111.67 (m; 2F); À124.49 (m; 2F); À126.05 (m; 2F).
3
1H NMR (CDCl3):
d
= 3.83 (s, 3H, OCH3), 6.05 (dt, JHH = 16 Hz,
3JHF = 12 Hz, 1H, CF2–CH); 6.85–6.95 (m; 2H, aromatic protons), 7.1
(dt, 3JHH = 16 Hz, 4JHF = 2.3 Hz, Ar–CH), 7.38–7.44 (m; 2H, aromatic
Acknowledgments
protons). 13C NMR (CDCl3): = 55.5 (s, OCH3); 111.8 (t; 2JCF = 23 Hz,
d
These investigations were supported by the Hungarian Scientific
Research Foundation (OTKAK 062191 ‘‘Sustainable fluorous chem-
istry’’). The European Union and the European Social Fund have
provided financial support to the project under the grant agreement
CF2–CH); 114.5 (s; CAr); 126.5 (s; CAr(ipso)); 129.4 (s; CAr); 139.4 (t;
3JCF = 10 Hz; Ar–CH). 19F NMR (CDCl3):
3F); À111.32 (m; 2F); À124.62 (m; 2F); À126.25 (m; 2F).
d
= À81.58 (t; 3JFF = 10.5 Hz,
´
´
´
no. TAMOP_4.2.1./B-09/1/KMR-2010-0003. Agnes Csapo thanks the
‘Sanofi-aventis/Chinoin’ for a PhD fellowship.
4.7.8. (E)-1-Methyl-2-(3,3,4,4,5,5,6,6,6-nonafluoro-hexen-1-yl)-
benzene (7n)
The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6n (0.52 g,
2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 7 days. Yield: 0.13 g (16.5%)
Appendix A. Supplementary data
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.jfluchem.2012.03.007.
colorless oil. GC assay: 90%.
3
1H NMR (CDCl3):
d
= 2.66 (s, 1H, CH3), 6.35 (dt, JHH = 16 Hz,
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benzene (7o)
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2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 7 days. Yield: 0.72 g (91.3%)
colorless oil. GC assay: 93%.
3
1H NMR (CDCl3):
d
= 2.28 (s, 3H, CH3), 6.05 (dt, JHH = 16 Hz,
3JHF = 12 Hz, 1H, CF2–CH); 7.00–7.30 (m; 5H, Ar–CH overlaps with
the aromatic protons). 13C NMR (CDCl3):
d = 21.5 (s, CH3), 113.3 (t;
2JCF = 23 Hz, CF2–CH); 127.8 (s; CAr); 129.8 (s; CAr)); 131.0 (s;
´
´
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3
C
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´
(d) J. Rabai, in: J.A. Gladysz, D.P. Curran, I.T. Horvath (Eds.), Handbook of Fluorous
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osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6p (0.67 g,
2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 7 days. Yield: 0.24 g (25%)
colorless oil. GC assay: 90%.
For preparation of F-styrenes (RfnCH5CHAr), see:
ˆ
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aromatic protons). 13C NMR (CDCl3): = 115.1 (t, 2JCF = 23 Hz, CF2–
CH), 124.7 (s; CAr,ipso), 129.2 (s, CAr), 132.4 (s, CAr), 132.6 (s; CAr,ipso),
d
= 6.22 (dt, 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
´
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3
138.7 (t, JCF = 10 Hz, Ar–CH). 19F NMR (CDCl3):
d
= À81.56 (t;
3JFF = 10.5 Hz, 3F); À112.0 (m; 2F); À124.5 (m; 2F); À126.2 (m; 2F).
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(7q)
´
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The reaction was performed according to GP-4 using fluor-
osilane 5a (0.76 g; 2.37 mmol) and iodoarene 6q (0.60 g,
2.37 mmol). TBAFÁ3H2O (1.5 g; 4.74 mmol) and Pd(OAc)2
(0.021 g, 4 mol%) in 3 ml of DMF for 5 days. Yield: 0.45 g (51%),
yellow liquid, GC: 94%.
1H NMR (CDCl3):
CH); 7.20–8.0 (m; 9H, Ar–CH overlaps with the aromatic protons).
13C NMR: = 117.73 (t; 2JCF = 24 Hz; CH55CH–CF2); 123.56 (s, CAr);
d
= 6.15 (dt, 3JHH = 16 Hz, 3JHF = 12 Hz, 1H, CF2–
d
125.38 (s; CAr,ipso), 125.86 (s; CAr); 126.77 (s; CAr); 127.42 (s; CAr);
129.20 (s; CAr); 130.82 (s; CAr); 131.52, (s, C); 131.67 (s, C); 137.96