Preparation of perfluorocyclopentenylmetal species and their cross-coupling reaction with electrophiles-Remarkable accesses to?versatile perfluorocyclopentene derivatives

Article abstract of DOI:10.1016/j.tet.2008.02.089

On treating perfluorocyclopentene with bis(tributylstannyl)cyanocuprate in THF at -78 °C for 1 h, perfluorocyclopentenylstannane was obtained in good yield. The reaction of the fluorinated vinylstannane with n-BuLi in THF at -78 °C for 1 h, followed by ad

Full text of DOI:10.1016/j.tet.2008.02.089

Available online at www.sciencedirect.com
Tetrahedron 64 (2008) 4215e4223
www.elsevier.com/locate/tet
Preparation of perfluorocyclopentenylmetal species and their
cross-coupling reaction with electrophilesdRemarkable accesses
to versatile perfluorocyclopentene derivatives
*
Shigeyuki Yamada, Emi Ishii, Tsutomu Konno, Takashi Ishihara
Department of Chemistry and Materials Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
Received 20 December 2007; received in revised form 26 February 2008; accepted 27 February 2008
Available online 29 February 2008
Abstract
On treating perfluorocyclopentene with bis(tributylstannyl)cyanocuprate in THF at ꢀ78 ꢁC for 1 h, perfluorocyclopentenylstannane was
obtained in good yield. The reaction of the fluorinated vinylstannane with n-BuLi in THF at ꢀ78 ꢁC for 1 h, followed by addition of carbonyl
compounds, gave the corresponding allyl alcohols in good yields. On the other hand, Pd(0)-catalyzed cross-coupling reaction of perfluorocy-
clopentenylstannane with benzyl chloroformate in THF at reflux temperature for 2 h proceeded smoothly to form the decarbonated coupling
product in high yield.
Ó 2008 Elsevier Ltd. All rights reserved.
Keywords: Perfluorinated vinylstannane; SneLi exchange reaction; Perfluoroallyl alcohols; Stille-type coupling reaction
1. Introduction
corresponding mono- (2) and/or di-substituted perfluorocyclo-
pentenes (3) in good yields.8 Moreover, a large excess amount
of stabilized carbanions, such as diethyl sodiomalonate and tri-
phenylphosphonium methylide, also underwent continuous ad-
ditioneelimination/1,4-HF elimination/1,6-conjugate addition
sequence, leading to 1,3-disubstituted products 4 in excellent
yields (Scheme 1).9
The reaction of perfluorocyclopenten-1-ylmetal species with
various electrophiles would also bring about a new and comple-
mentary entry to the synthetic methods for various types of
perfluorocyclopentene derivatives, since little attention has
been paid to this subject thus far. Herein, we wish to disclose
a first preparation of perfluorocyclopent-1-enylstannane (5-Sn)
and the cross-coupling reaction with various electrophiles
(Scheme 2).
Incorporation of fluorine(s) into organic molecules often
changes their structure, stability, reactivity, and biological
activity, and thereby frequently leads to the discovery of novel
and potent applications in various domains from liquid crystal-
line materials to biologically active substances, peptide iso-
steres or enzyme inhibitors.1 Consequently, a wide variety of
methods have hitherto been developed for the preparation of
various types of fluorine-incorporated compounds.2
Among such compounds, organic molecules containing a
perfluorocyclopentene backbone have recently been recognized
as one of the most attractive units for the applications to opto-
electronic devices, etc.3 Additioneelimination reactions of
perfluorocyclopentene (1) with nucleophiles would provide
a promising entry to the preparation of various perfluorocyclo-
pentene derivatives.4e7 Very recently, we reported that the reac-
tion of 1 with various nucleophiles, such as Grignard reagents
and organolithium reagents, took place smoothly to give the
2. Results and discussion
2.1. Preparation of perfluorocyclopent-1-enylstannane (5-Sn)
Initially, we examined the preparation of perfluorocyclopenten-
1-ylstannane 5-Sn through the reaction of perfluorocyclopentene
* Corresponding author. Tel.: þ81 75 724 7504; fax: þ81 75 724 7580.
E-mail address: ishihara@kit.ac.jp (T. Ishihara).
0040-4020/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2008.02.089

4216
S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
F
F
Addition of copper(I) salt, such as CuBr and CuI, did not
also give satisfactory results. However, changing copper(I)
salt from CuBr and CuI to CuCN significantly improved the
yield, the desired vinylstannane 5-Sn being obtained in 34%
yield (entries 2e4). As shown in entry 5, when 2.2 equiv of
bis(tributylstannyl)cyanocuprate11 was used, the reaction pro-
ceeded smoothly to provide the corresponding 5-Sn in 49%
yield. The use of methyl or 2-thienyl group as a dummy li-
gand12 was not effective, 5-Sn was given in only 12 or 18%
yield, respectively (entries 7 and 8). The reaction of an excess
amount of 1 (3.0 equiv) with 1.0 equiv of bis(tributylstannyl)-
cyanocuprate took place effectively to give the corresponding
vinylstannane 5-Sn in 52% yield (entry 9). It was found that
the reaction at ꢀ50 ꢁC for 1 h or at ꢀ78 ꢁC for 15 h apprecia-
bly decreased the yield of 5-Sn (entries 10 and 11). Although
the vinylstannane 5-Sn could not be obtained in an analytically
pure form, due to the contaminated tetrabutyltin, we found that
the contamination did not lead to a significant decrease of the
yields of the coupling products.
Grignard reagents
ArMgBr
F
F
F
F
Ar
F
2
Organolithium reagents
RLi (R = aryl, heteroaryl,
alkyl, alkenyl, alkynyl)
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
R
R
R
F
1
3
Stabilized Carbanions
diethyl sodiomalonate
triphenylphosphonium methylide
F
F
R
4
Scheme 1. Previous research outline.
F
F
F F
F
F
Umpolung
F
F
F
F
electrophiles
F
F
F
F
F
F
F
F
F
Sn
F
El.
F
F
1
5-Sn
3. Coupling reaction with various electrophiles
Electrophilic
Nucleophilic
sp2-carbon
sp2-carbon
3.1. Coupling reaction with aldehydes or ketones through
SneLi exchange reaction
Scheme 2. Intended research outline.
With the fluorinated vinylstannane 5-Sn in hand, our atten-
tion was directed toward the coupling reaction of 5-Sn with
various electrophiles. Thus, the treatment of 5-Sn with
1.5 equiv of butyllithium in THF at ꢀ78 ꢁC for 1 h, followed
by the addition of carbonyl compounds, led to the correspond-
ing allylic alcohols. The results are tabulated in Table 2.
The reaction of 5-Li with 2.0 equiv of benzaldehyde (6a) in
THF at ꢀ78 ꢁC for 2 h did not give a satisfactory result, the cor-
responding allyl alcohol 7a being obtained in only 25% yield
(entry 1). When 5.0 equiv of 6a was used, the yield of 7a signif-
icantly increased to 88% (entry 2). As shown in entry 3, aromatic
aldehyde having an electron-donating group at p-position in
benzene ring, like 4-methylbenzaldehyde (6b), could partici-
pate in the coupling reaction. In the case of 4-chlorobenz-
aldehyde (6c) or cinnamaldehyde (6f), the yield of 7c or 7f
was decreased to 62 or 41% yield. Additionally, aliphatic alde-
hydes, such as 3-phenylpropionaldehyde (6d) and cyclohexane-
carboxaldehyde (6e), were found to be much less reactive in this
coupling reaction, while the addition of BF3$OEt2 was very ef-
fective, leading to the corresponding allylic alcohol 7d or 7e in
34e85% yield as shown in entries 5, 7, 9, and 11. As described in
entries 12e16, various ketones, such as acetophenone (6g), 4-
methylacetophenone (6h), 4-chloroacetophenone (6i), and benz-
ylideneacetone (6j), were also found to be good electrophiles,
the corresponding allylic alcohols 7g, 7h, 7i, and 7j being ob-
tained in 60e78% yields. In Table 2, the difficulty of the sepa-
ration between the coupling product and carbonyl compound
by silica gel column chromatography resulted in the low isolated
yield.
(1) with tributylstannyllithium.10 Thus, the treatment of 1.0 equiv
of 1 with 2.2 equiv of tributylstannyllithium in THF at ꢀ78 ꢁC for
2 h led to a complex mixture, no desired product being obtained
(Table 1, entry 1).
Table 1
Preparation of perfluorocyclopent-1-enylstannane (5-Sn)
Cu(I) salt + SnLi
L-Li
F
F
F
F
F
F
F
F
F
F
F
F
+
Sn(L)CuX•Li2
THF, -78 °C, 1 h
(Sn = n-Bu3Sn)
F
F
F
Sn
1
5-Sn
Entry
Cu(I) salt
L
Equiv of 1
Equiv of
cuprate
Yielda/% of
5-Sn
1b
2
None
CuBr
CuI
n-Bu3Sn
n-Bu3Sn
n-Bu3Sn
n-Bu3Sn
n-Bu3Sn
None
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
3.0
3.0
3.0
d
d
9
1.1
1.1
1.1
2.2
2.2
2.2
2.2
1.0
1.0
1.0
3
7
4
CuCN
CuCN
CuCN
CuCN
CuCN
CuCN
CuCN
CuCN
34
49
38
12
18
52
35
15
5
6c
7
Me
8
2-Thienyl
n-Bu3Sn
n-Bu3Sn
n-Bu3Sn
9
10d
11e
a
Determined by 19F NMR.
Reaction of 1 with 2.2 equiv of n-Bu3SnLi in THF at ꢀ78 ꢁC for 1 h was
b
carried out.
c
Lower-ordered cyanocuprate (n-Bu3SnCuCN$Li) was used.
The coupling reaction with other electrophiles,13 such as
acyl chloride, chloroformate, and N-tosyl benzaldimine, were
d
e
Carried out at ꢀ50 ꢁC for 1 h.
Carried out at ꢀ78 ꢁC for 15 h.

S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
4217
Table 2
Cross-coupling reaction of 5-Sn with carbonyl compounds through SneLi
exchange reaction
Table 3
Pd(0)-catalyzed cross-coupling reaction of 5-Sn with benzyl chloro-
formate (8k)
Pd catalyst,
F
F
F F
F
F
F
F
CuI (10 mol%)
F
F
F
F
F
F
F
F
Li
n-BuLi (1.5 equiv)
THF, -78 °C, 1 h
F
F
F
F
F
F
F
ClCO Bn (8k, 2.2 equiv.)
2
THF, reflux, 2 h
(Sn = n-Bu Sn)
F
Bn
F
Sn
F
3
F
Sn
F
5-Sn
5-Li
5-Sn
9k
O
R1 R2
Yielda/%
of 9k
Recoverya/%
of 5-Sn
F
F
Entry
Pd catalyst (mol %)
F
F
F
F
(6, 5.0 equiv)
THF, -78 °C, 2 h
1b
Cl2Pd(PPh3)2 (5)
1/2Pd2(dba)3$CHCl3 (5)
0
0
68
87
37
58
Trace
4
F
OH
R1
2
R2
3c
1/2Pd2(dba)3$CHCl3þ2Ph3P (5)
1/2Pd2(dba)3$CHCl3þ2(o-Tol)3P (5)
1/2Pd2(dba)3$CHCl3þ2Cy3P (5)
1/2Pd2(dba)3$CHCl3þ2n-Bu3P (5)
1/2Pd2(dba)3$CHCl3þ2t-Bu3P (5)
1/2Pd2(dba)3$CHCl3þ2(EtO)3P (5)
1/2Pd2(dba)3$CHCl3þ2(2-furyl)3P (5)
1/2Pd2(dba)3$CHCl3þdppe (5)
1/2Pd2(dba)3$CHCl3þdppf (5)
1/2Pd2(dba)3$CHCl3þdppf (5)
1/2Pd2(dba)3$CHCl3þdppf (5)
1/2Pd2(dba)3$CHCl3þdppf (5)
1/2Pd2(dba)3$CHCl3þdppf (20)
1/2Pd2(dba)3$CHCl3þdppf (20)
Trace
0
7
4c
5c
0
Entry
R1
R2
Yielda/% of 7
6c
0
1b
2
Ph
Ph
H
H
H
H
H
H
H
H
H
H
H
(a)
(a)
(b)
(c)
(c)
(d)
(d)
(e)
(e)
(f)
25
7c
0
26
60
38
57
40
0
88 (61)
82 (60)
62
8
6
3
4-MeC6H4
4-ClC6H4
4-ClC6H4
PhCH2CH2
PhCH2CH2
Cy
9
13
0
4
10
11
12c,d
13c,e
14c,f
15
16g
a
5c
6
85 (78)
Trace
34
38
4
7c
8
7
0
Trace
49 (18)
41
45
87
86
0
9c
10
11c
Cy
(E)-PhCH]CH
(E)-PhCH]CH
0
0
(f)
72 (55)
Determined by 19F NMR.
b
c
d
e
f
Carried out in the presence of CuCN in toluene at 80 ꢁC for 2 h.
Unknown product was obtained.
CuBr was employed as Cu(I) salt.
CuCN was employed as Cu(I) salt.
Carried out for 20 h.
12
13
14c
15c
16c
a
Ph
Me
Me
Me
Me
Me
(g)
(h)
(h)
(i)
78 (49)
60 (35)
72 (42)
72 (50)
67
4-MeC6H4
4-MeC6H4
4-ClC6H4
(E)-PhCH]CH
(j)
g
Determined by 19F NMR. Values in parentheses are of isolated yields.
With 2.0 equiv of aldehyde.
BF3$OEt2 was employed as Lewis acid.
With 5 mol % of CuI.
b
c
like 1,10-bis(diphenylphosphino)ethane (dppe), did not lead to
a satisfactory result. As shown in entries 12 and 13, it was found
that CuBr and CuCN were less efficient and that CuI was the
additive of choice. Increasing the amount of catalyst from 5
to 20 mol % caused a significant improvement of the yield (en-
try 15). Thus, when the coupling reaction in the presence of
20 mol % of palladium catalyst and 10 mol % of CuI in THF
at reflux temperature for 2 h was performed, 9k was obtained
in 87% yield. The coupling reaction in the presence of
5 mol % of CuI also proceeded smoothly to give the corre-
sponding 9k in 86% yield (entry 16).
examined. However, any trace of the corresponding coupling
products were not detected at all in all cases.
3.2. Pd(0)-catalyzed cross-coupling of 5-Sn with
chloroformates
We next attempted the Pd(0)-catalyzed cross-coupling reac-
tion of 5-Sn with benzyl chloroformate 8k.14 Initial studies
were started from the coupling reaction conditions reported pre-
viously14a (entry 1, Table 3). Thus, the coupling reaction of 5-
Sn with 8k in the presence of 5 mol % of Cl2Pd(PPh3)2 and
10 mol % of CuCN in toluene at 80 ꢁC for 2 h was conducted.
However, no coupling product was obtained at all. Then, we
reexamined the coupling reaction of 5-Sn with 8k in detail.
In entries 2e7, various phosphine ligands, such as (o-Tol)3P,
Cy3P, n-Bu3P, and t-Bu3P, were carefully examined, however,
no trace of the desired coupling product was detected. Interest-
ingly, the use of (EtO)3P or (2-furyl)3P as a ligand caused
a small amount of formation of decarbonated product, i.e., 1-
benzylperfluorocyclopentene (9k), together with 60 or 38%
recovery of the starting material, respectively.
Subsequently, the coupling reaction of 5-Sn with commer-
cially available chloroformates 8 using the above optimum
reaction conditions (entry 16 in Table 3) was carried out, as
shown in Scheme 3.
Pd2(dba)3•CHCl3/dppf(20 mol%)
F
F
CuI (5 mol%)
F F
F
F
F
F
F
F
F
F
ClCO2R (8, 2.2 equiv)
THF, reflux, 2 h
F
Sn
F
R
9
5-Sn
R = Bn (k) : 86%
R = Allyl (l) : 38%
R = n-Oct (m) : 0%
R = Ph (a) : 0%
Changing the phosphine ligand from the above monodentate
ligands to a bidentate ligand, 1,10-bis(diphenylphosphino)ferro-
cene (dppf) improved the yield of 9k. Other bidentate ligand,
Scheme 3. Cross-coupling reaction of 5-Sn with various chloroformates.

4218
S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
The coupling reaction with allyl chloroforomate (8l) took
obtained in 85 or 90% yield, respectively. Benzyl-type chlorides
having an electron-donating group at p-position in benzene
ring, e.g., 4-methoxybenzyl chloride (10n) or 4-methylbenzyl
chloride (10o), also participated in the coupling reaction, lead-
ing to the corresponding benzylated product 9n or 9o in 95 or
93% yield, respectively (entries 4 and 5). On the other hand,
the reaction with 4-cyanobenzyl chloride (10p) was slightly
sluggish, the corresponding 9p being obtained in 55% yield.
As shown in entries 7 and 8, 2-(chloromethyl)furan (10q) or
-thiophene (10r) also participated well in the coupling reaction,
giving rise to the corresponding coupling product 9q or 9r in 63
or 66% yield, respectively. (E)-Cinnamyl chloride (10s) was not
effective for the coupling reaction, but the use of the corre-
sponding bromide facilitated the coupling reaction, affording
the coupling product 9s in 75% yield (entries 9 and 10). The
coupling reaction with 3-phenyl-2-propyn-1-yl chloride (10t)
also took place smoothly to give the coupling product 9t in
85% yield. The volatility of the products given in Table 4 causes
the decrease of the isolated yields.
On the basis of the results that the Pd(0)-catalyzed cross-
coupling reaction with benzyl chloroformate or benzyl chloride
afforded the same product, 1-benzylperfluorocyclopentene 9k
in similar yields, both reactions may proceed via a common
benzylpalladium complex Int-B. Therefore, the following reac-
tion mechanism may be proposed as shown in Scheme 5. Thus,
the coupling reaction presumably proceeds via the following
steps: (1) oxidative addition of CeCl bond in chloroformate
to Pd(0) (Int-A), (2) formation of benzylpalladium chloride
(Int-B) via evolution of CO2, which is also formed from benzyl
chloride and palladium catalyst, (3) transmetallation of vinyl
copper species 5-Cu, which is formed by treatment of 5-Sn
with copper(I) salt, leading to Int-C, (4) reductive elimination
to give the coupling product 9k and regeneration of Pd(0).
place to form the corresponding 1-allylperfluorocyclopentene
(9l), though the yield was unsatisfactory. Other chloroformates
(n-alkyl or aryl chloroformates, 8m and 8a) could not partic-
ipate in the coupling reaction at all.
We next attempted the Stille-type cross-coupling reaction of
5-Sn with other halides such as benzoyl chloride and aryl or alkyl
halidesunderthesameconditions. Thus, thecross-couplingreac-
tion of 5-Sn with benzoyl chloride, iodobenzene or b-phenethyl
bromide in the presence of 10 mol % of Pd2(dba)3$CHCl3,
20 mol % of dppf, and 5 mol % of CuI in THF at reflux temper-
ature for 2 h did not lead to satisfactory results, while the use of
benzyl bromide15 as a halide was so effective for the coupling re-
action, affording the corresponding coupling product 9k, quanti-
tatively. It was found, moreover, that the corresponding chloride
10k could also be applied to the coupling reaction, 9k being
obtained in 78% yield (Scheme 4).
Pd2(dba)3•CHCl3/dppf (20 mol%)
CuI (5 mol%)
F
F
F
F
F
F
F
F
BnCl (10k, 2.2 equiv)
F
F
F
F
THF, reflux, 2 h
F
Sn
F
Bn
9k
5-Sn
78%
Scheme 4. Pd(0)-catalyzed cross-coupling reaction of 5-Sn with benzyl chlo-
ride (10k).
Then, our interest was directed toward the Pd(0)-catalyzed
cross-coupling reaction of 5-Sn with various benzyl-type chlo-
rides 10. The results are summarized in Table 4.
Table 4
Pd(0)-catalyzed cross-coupling reaction of 5-Sn with benzyl-type chlorides 10
Pd2(dba)3•CHCl3/dppf (20 mol%)
F
F
F
F
CuBr (10 mol%)
F
F
F
F
F
F
F
RCH2Cl (10, 2.2 equiv)
4. Conclusion
THF, reflux, 2 h
F
F
Sn
F
CH2R
In conclusion, we discovered perfluorocyclopent-1-enylstan-
nane (5-Sn) as a new perfluorinated vinylmetal species. Treat-
ment of the perfluorinated vinylstannane 5-Sn with n-BuLi in
THF at ꢀ78 ꢁC, followed by addition of aromatic aldehydes
or ketones in the presence of BF3$OEt2 at ꢀ78 ꢁC, afforded
the corresponding secondary or tertiary allyl alcohols in good
yields, respectively. The Pd(0)-catalyzed cross-coupling reac-
tion of 5-Sn with benzyl chloroformate (8k) in the presence of
20 mol % of Pd2(dba)3$CHCl3/dppf and 5 mol % of CuI in
THF at reflux temperature for 2 h proceeded smoothly to form
the decarbonated coupling product in high yield. We also found
that the Pd(0) catalyst, i.e., Pd2(dba)3$CHCl3/dppf, also facili-
tated the coupling reaction of 5-Sn with various benzyl-type
chlorides, leading to the coupling products in good yields.
9
5-Sn
Entry
R
Yielda/% of 9
Recoverya/% of 5-Sn
1b
2c
3
Ph (k)
Ph (k)
Ph (k)
78
85
18
12
9
90 (41)
95 (39)
97 (60)
55
4
4-MeOC6H4 (n)
4-MeC6H4 (o)
4-NCC6H4 (p)
2-Furyl (q)
0
5
0
6
Trace
0
7
63
70
8
2-Thienyl (r)
(E)-PhCH]CH (s)
(E)-PhCH]CH (s)
PhC^CH (t)
0
9d
10e
11
a
48
75 (52)
85 (45)
10
0
0
Determined by 19F NMR. Values in parentheses are of isolated yields.
CuI (5 mol %) was employed.
CuI (10 mol %) was employed.
b
c
d
e
5. Experimental
Unknown product was obtained in 20% yield.
The corresponding bromide was used.
5.1. Measurements and materials
As shown in entries 2 and 3, when 10 mol % of CuI or CuBr
was employed in the coupling reaction with benzyl chloride
(10k), a slight increase of the yield was observed, 9k being
1H and 13C NMR spectra were recorded with a Bruker
DRX-500 (500.13 MHz for 1H and 125.75 MHz for 13C)

S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
4219
F
F
F
F
F
ClCO2Bn (8k)
Pd(0)
F
F
Bn
Reductive
Elimination
Oxidative
Addition
9k
F
F
BnCl (10k)
O
F
F
F
F
Cl
Pd OBn
(II)
Int-A
F
Pd Bn
(II)
Int-C
Trans-
metallation
CuCl
Cl
Bn
F
F
F
F
Decarbonation
Copper(I)
salt
Pd
(II)
F
F
F
F
F
F
F
F
Cu
CO2
Int-B
F
F
Sn
5-Cu
5-Sn
Scheme 5. Proposed reaction mechanism for Pd(0)-catalyzed cross-coupling reaction of 5-Sn with 8k or 10k.
spectrometer in a chloroform-d (CDCl3) solution with tetra-
5.2.1. 1-(Tributylstannyl)-2,3,4,4,5,5-heptafluorocyclo-
methylsilane as an internal reference. A JEOL JNM-AL400
(376.05 MHz) spectrometer was used to record 19F NMR
spectra in CDCl3 using CFCl3 as an internal standard. Infrared
spectra (IR) were determined in a liquid film or KBr disk
method with an FT/IR-4100 (JASCO) instrument. High resolu-
tion mass spectra were taken with a JEOL JMS-700 MS
spectrometer.
Anhydrous tetrahydrofuran (THF) was purchased from
Wako Pure Chemical Industries, Ltd. n-BuLi (a 1.6 M hexane
solution) was commercially available from Wako Pure Chem-
ical Industries, Ltd. All chemicals were of reagent grade and,
if necessary, were purified in the usual manner prior to use.
All reactions were carried out under an atmosphere of argon.
Thin layer chromatography (TLC) was done with Merck silica
gel 60F254 plates and column chromatography was carried out
with Wako gel C-200.
pentene (5-Sn)
1H NMR (CDCl3) d 0.91 (t, J¼7.3 Hz, 9H), 1.1e1.2 (m, 6H),
1.3e1.4 (m, 6H), 1.5e1.6 (m, 6H); 13C NMR (CDCl3) d 10.62,
13.48, 27.01, 28.56, 111.21 (tq, J¼261.8, 25.8 Hz), 111.27
(tquint.d, J¼276.8, 24.5, 1.9 Hz), 119.32 (tddt, J¼252.9, 46.2,
45.7, 4.3 Hz), 126.25 (dtquint., J¼35.8, 35.8, 4.3 Hz), 162.0e
165.3 (dm, J¼285.0 Hz); 19F NMR (CDCl3) d ꢀ129.38 (s,
2F), ꢀ119.18 (br s, 1F), ꢀ119.14 (br s, 1F), ꢀ117.8 to
ꢀ117.7 (m, 1F), ꢀ100.3 to ꢀ100.2 (m, 2F); IR (neat) 2961,
2857, 1655, 1466, 1355, 958 cmꢀ1; HRMS (FAB) found: m/z
482.1015, calcd for (Mþ) C17H27F7Sn: 482.1023.
5.3. Typical procedure for the coupling reaction of 5-Sn with
benzaldehyde through SneLi exchange reaction
A 30 mL two-necked round-bottomed flask equipped with
a magnetic stirrer bar, a rubber septum, and an inlet tube for
argon was charged with 40 wt % solution of 5-Sn (0.241 g,
0.2 mmol) in THF (1 mL). To this solution was slowly added
a1.6 Mhexane solutionof n-BuLi(0.19 mL, 0.3 mmol)via asy-
ringe at ꢀ78 ꢁC. The whole mixture was stirred at the same tem-
perature for 1 h. After being stirred at ꢀ78 ꢁC for 1 h, the
reaction mixture was treated with 0.106 g (1.0 mmol) of benz-
aldehyde at ꢀ78 ꢁC for 1 h. After stirring for 1 h, the reaction
mixture was poured into ice-cooled saturated aqueous NH4Cl
(30 mL), followed by extraction with Et2O (30 mLꢂ3). The or-
ganic layers were washed with 5% aqueous KF solution, and
dried over anhydrous Na2SO4, filtered, and concentrated in va-
cuo. Column chromatography of the residue using hexane/ethyl
acetate (12:1) yielded pure 1-phenyl-(2,3,3,4,4,5,5-heptafluoro-
cyclopenten-1-yl)methanol (7a, 0.033 g, 61%). The coupling
product 7j could not be separated as a pure product.
5.2. Preparation of tributyl(perfluorocyclopent-1-
enyl)stannane (5-Sn)
A 50 mL three-necked round-bottomed flask equipped with
a magnetic stirrer bar, a thermometer, a rubber septum, and an
inlet tube for argon was charged with a suspension of 0.045 g
(0.5 mmol) of CuCN in THF (1 mL). To the suspension was
slowly added a THF solution of 1.0 mmol of tributylstannyl-
lithium (0.75 mL), prepared from bis(tributylstannane) and
n-BuLi in THF at 0 ꢁC for 0.5 h, via a syringe at ꢀ78 ꢁC. The
whole mixture was stirred at ꢀ50 ꢁC for 10 min, and to the
resulting solution was slowly added 0.318 g (1.5 mmol) of per-
fluorocyclopentene 1 in THF (2 mL) via a syringe at ꢀ78 ꢁC.
After being stirred for 1 h at ꢀ78 ꢁC, the reaction mixture was
poured into a saturated aqueous NH4Cl (30 mL), followed by
extraction with Et2O (20 mLꢂ5). The organic layers were dried
over anhydrous Na2SO4, filtered, and concentrated in vacuo.
Column chromatography of the residue using hexane yielded
1-(tributylstannyl)-2,3,3,4,4,5,5-heptafluorocyclopentene (5-Sn),
as contaminated by ca. 40 wt % of tetrabutyltin.
5.3.1. (2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)phenyl-
methanol (7a)
1H NMR (CDCl3) d 2.81 (d, J¼4.3 Hz, 1H), 5.69 (br s, 1H),
7.3e7.4 (m, 5H); 13C NMR (CDCl3) d 67.54, 110.03 (tquint.d,

4220
S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
J¼274.4, 23.9, 4.1 Hz), 110.63 (tq, J¼259.5, 24.0 Hz), 115.29
(ttdt, J¼258.7, 24.8, 10.7, 2.5 Hz), 125.23 (tt, J¼24.8, 5.8 Hz),
126.14, 129.14, 129.26, 138.42, 150.7e154.7 (dm, J¼
298.4 Hz); 19F NMR (CDCl3) d ꢀ131.49 (dd, J¼239.2,
4.9 Hz, 1F), ꢀ130.43 (d, J¼239.2 Hz, 1F), ꢀ128.9 to
ꢀ128.6 (m, 1F), ꢀ120.79 (dd, J¼261.0, 14.7 Hz, 1F),
ꢀ118.57 (dd, J¼261.0, 14.7 Hz, 1F), ꢀ110.43 (dd, J¼258.3,
12.0 Hz, 1F), ꢀ107.50 (dd, J¼258.3, 12.0 Hz, 1F); IR (neat)
3376, 3070, 1709, 1456, 1385, 1204, 1155 cmꢀ1; HRMS
(EI) found: m/z 300.0388, calcd for (Mþ) C12H7F7O:
300.0385.
5.3.5. Cyclohexyl-(2,3,3,4,4,5,5-heptafluorocylopenten-1-
yl)methanol (7e)
1H NMR (CDCl3) d 1.04e1.35 (m, 5H), 1.45e2.02 (m,
7H), 4.38 (br s, 1H); 19F NMR (CDCl3) d ꢀ131.76 (dd,
J¼239.2, 4.9 Hz, 1F), ꢀ130.31 (d, J¼239.2 Hz, 1F), ꢀ129.4
to ꢀ129.2 (m, 1F), ꢀ121.12 (dd, J¼261.3, 12.0 Hz, 1F),
ꢀ118.27 (dd, J¼261.3, 12.0 Hz, 1F), ꢀ111.28 (dd, J¼263.6,
4.9 Hz, 1F), ꢀ106.58 (dd, J¼263.6, 4.9 Hz, 1F); IR (neat)
3423, 2933, 1708, 1422, 1330, 1271, 1158, 1122 cmꢀ1
;
HRMS (FAB) found: m/z 307.0931, calcd for (MþH)
C12H14F7O: 307.0934.
5.3.2. (2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)-4-methyl-
phenylmethanol (7b)
5.3.6. 1-(2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)-3-
phenyl-2-propen-1-ol (7f)
1H NMR (CDCl3) d 2.37 (s, 3H), 2.46 (d, J¼4.8 Hz, 1H),
5.68 (br s, 1H), 7.22 (AB q, J¼8.0 Hz, 2H), 7.30 (AB q,
J¼8.0 Hz, 2H); 13C NMR (CDCl3) d 21.17, 67.62, 110.00
(tquint.d, J¼273.6, 21.5, 3.3 Hz), 110.63 (tqd, J¼282.7, 24.0,
2.4 Hz), 115.29 (ttd, J¼260.4, 29.7, 7.4 Hz), 125.40 (td,
J¼29.7, 5.8 Hz), 126.13, 129.83, 135.55, 139.35, 150.7e
154.6 (dm, J¼294.3 Hz); 19F NMR (CDCl3) d ꢀ131.48 (dd,
J¼239.2, 4.9 Hz, 1F), ꢀ130.13 (d, J¼239.2 Hz, 1F), ꢀ129.2
to ꢀ128.9 (m, 1F), ꢀ120.79 (dd, J¼263.2, 14.7 Hz, 1F),
ꢀ118.51 (dd, J¼263.2, 14.7 Hz, 1F), ꢀ110.48 (dd, J¼256.9,
12.0 Hz, 1F), ꢀ107.55 (dd, J¼256.9, 12.0 Hz, 1F); IR (neat)
3323, 2928, 1708, 1330, 1275, 1156, 1083 cmꢀ1; HRMS
(FAB) found: m/z 314.0548, calcd for (Mþ) C13H9F7O:
314.0542.
1H NMR (CDCl3) d 2.34 (br s, 1H), 5.34 (d, J¼6.8 Hz, 1H),
6.32 (dd, J¼15.0, 6.8 Hz, 1H), 6.77 (d, J¼15.0 Hz, 1H), 7.30e
7.44 (m, 5H); 13C NMR (CDCl3) d 66.15, 110.09 (tquint.d,
J¼275.3, 240, 3.3 Hz), 110.61 (tqd, J¼258.6, 23.1, 2.5 Hz),
115.44 (ttdt, J¼258.7, 24.8, 9.1, 2.5 Hz), 124.25 (tt, J¼28.1,
5.8 Hz), 124.86, 126.92, 128.77, 128.83, 134.36, 135.19,
151.0e155.0 (dm, J¼299.2 Hz); 19F NMR (CDCl3)
d ꢀ131.33 (d, J¼239.2 Hz, 1F), ꢀ130.36 (d, J¼239.2 Hz,
1F), ꢀ129.1 to ꢀ128.7 (m, 1F), ꢀ120.63 (dd, J¼258.7,
14.7 Hz, 1F), ꢀ118.74 (dd, J¼258.7, 14.7 Hz, 1F), ꢀ110.13
(dd, J¼256.1, 9.8 Hz, 1F), ꢀ107.76 (dd, J¼256.1, 9.8 Hz,
1F); IR (neat) 3389, 3031, 2928, 1709, 1495, 1386, 1303,
1205, 1157, 1079 cmꢀ1; HRMS (FAB) found: m/z (Mþ)
326.0544, calcd for C14H9F7O: 326.0542.
5.3.3. 4-Chlorophenyl-(2,3,3,4,4,5,5-heptafluorocyclo-
penten-1-yl)methanol (7c)
5.3.7. 1-(2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)-1-
phenylethanol (7g)
1H NMR (CDCl3) d 2.50 (br s, 1H), 5.73 (br s, 1H), 7.35e
7.42 (m, 5H); 13C NMR (CDCl3) d 66.72, 110.07 (tquint.d,
J¼276.1, 24.0, 4.9 Hz), 110.52 (tqd, J¼259.5, 22.4, 4.1 Hz),
115.24 (ttd, J¼258.7, 28.0, 9.9 Hz), 124.78 (tt, J¼23.3,
5.8 Hz), 127.47, 129.35, 135.20, 136.82, 151.0e154.9 (dm,
J¼299.3 Hz); 19F NMR (CDCl3) d ꢀ131.47 (dd, J¼239.2,
4.9 Hz, 1F), ꢀ130.41 (d, J¼239.2 Hz, 1F), ꢀ128.3 to
ꢀ128.1 (m, 1F), ꢀ120.81 (dd, J¼261.3, 14.7 Hz, 1F),
ꢀ118.62 (dd, J¼261.3, 14.7 Hz, 1F), ꢀ110.39 (dd, J¼258.7,
9.8 Hz, 1F), ꢀ107.37 (dd, J¼258.7, 9.8 Hz, 1F); IR (neat)
1H NMR (CDCl3) d 1.95 (s, 3H), 2.51 (br s, 1H), 7.34e7.48
(m, 5H); 13C NMR (CDCl3) d 28.91, 73.39, 109.95 (tquint.d,
J¼274.4, 26.4, 4.9 Hz), 110.49 (tqd, J¼258.7, 25.6, 1.6 Hz),
115.6 (ttd, J¼260.3, 24.0, 9.9 Hz), 124.54, 128.57, 128.89,
133.15, 150.2e154.3 (dm, J¼297.5 Hz); 19F NMR (CDCl3)
d ꢀ131.86 (d, J¼239.2 Hz, 1F), ꢀ130.91 (d, J¼239.2 Hz,
1F), ꢀ126.4 to ꢀ126.2 (m, 1F), ꢀ120.78 (dd, J¼256.1,
12.0 Hz, 1F), ꢀ119.15 (dd, J¼256.5, 12.0 Hz, 1F), ꢀ108.71
(dd, J¼256.5, 12.0 Hz, 1F), ꢀ106.26 (dd, J¼256.5, 12.0 Hz,
1F); IR (neat) 3454, 2992, 1696, 1389, 1372, 1280, 1203,
1153, 1052 cmꢀ1; HRMS (EI) found: m/z 314.0547, calcd
for (Mþ) C13H9F7O: 314.0542.
3401, 2928, 1708, 1494, 1301, 1205, 1159, 1085 cmꢀ1
;
HRMS (FAB) found: m/z 333.9987, calcd for (MþH)
C12H6ClF7O: 333.9995.
5.3.4. 1-(2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)phenyl-
propan-1-ol (7d)
5.3.8. 1-(2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)-1-(4-
methylphenyl)ethanol (7h)
1H NMR (CDCl3) d 2.05e2.30 (m, 3H), 2.70e2.90 (m,
2H), 4.68 (br s, 1H), 7.18e7.38 (m, 5H); 19F NMR (CDCl3)
d ꢀ131.43 (d, J¼239.2 Hz, 1F), ꢀ130.52 (d, J¼239.2 Hz,
1F), ꢀ129.7 to ꢀ129.5 (m, 1F), ꢀ120.60 (dd, J¼243.7,
14.7 Hz, 1F), ꢀ118.93 (dd, J¼243.7, 14.7 Hz, 1F), ꢀ110.13
(dd, J¼256.1, 9.8 Hz, 1F), ꢀ107.94 (dd, J¼256.1, 9.8 Hz,
1F); IR (neat) 3424, 3030, 2930, 1709, 1497, 1455, 1372,
1276, 1157, 1121 cmꢀ1; HRMS (FAB) found: m/z 328.0710,
calcd for (Mþ) C14H11F7O: 328.0698.
1H NMR (CDCl3) d 1.93 (s, 3H), 2.47 (s, 3H), 2.42 (br s,
1H), 7.21 (AB q, J¼8.0 Hz, 2H), 7.33 (AB q, J¼8.0 Hz,
2H); 19F NMR (CDCl3) d ꢀ131.82 (d, J¼242.5 Hz, 1F),
ꢀ130.61 (d, J¼242.5 Hz, 1F), ꢀ126.7 to ꢀ126.4 (m, 1F),
ꢀ120.67 (dd, J¼256.1, 12.0 Hz, 1F), ꢀ119.21 (dd, J¼256.1,
12.0 Hz, 1F), ꢀ108.59 (dd, J¼28.7, 12.0 Hz, 1F), ꢀ106.46
(dd, J¼258.7, 12.0 Hz, 1F); IR (neat) 3636, 1696, 1388,
1333, 1280, 1203, 1155, 1051 cmꢀ1; HRMS (FAB) found:
m/z 328.0706, calcd for (Mþ) C14H11F7O: 328.0698.

S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
4221
5.3.9. 1-(4-Chlorophenyl)-1-(2,3,3,4,4,5,5-heptafluorocyclo-
5.5. Typical procedure for Pd(0)-catalyzed cross-coupling
penten-1-yl)ethanol (7i)
reaction of 5-Sn with benzyl chloride
1H NMR (CDCl3) d 1.93 (s, 3H), 2.67 (br s, 1H), 7.34e7.43
(m, 4H); 19F NMR (CDCl3) d ꢀ131.96 (dd, J¼239.1, 4.9 Hz,
1F), ꢀ130.89 (dd, J¼239.1, 4.9 Hz, 1F), ꢀ126.0 to ꢀ125.8
(m, 1F), ꢀ120.95 (dd, J¼253.8, 14.7 Hz, 1F), ꢀ119.07
(dd, J¼253.8, 14.7 Hz, 1F), ꢀ108.91 (dd, J¼258.3, 12.4 Hz,
1F), ꢀ106.00 (dd, J¼258.3, 12.4 Hz, 1F); IR (neat) 3465,
2931, 1697, 1492, 1389, 1284, 1204, 1155 cmꢀ1; HRMS
(FAB) found: m/z (Mþ) 348.0161, calcd for C13H8ClF7:
348.0152.
A 30 mL two-necked round-bottomed flask equipped with
a magnetic stirrer bar, a rubber septum, and an inlet tube
for argon was charged with a solution of 10 mol % of
Pd2(dba)3$CHCl3 (0.021 g, 0.02 mmol), 20 mol % of dppf
(0.022 g, 0.04 mmol), benzyl chloride (10k, 0.056 g,
0.44 mmol), 10 mol % of CuBr (0.003 g, 0.02 mmol) in THF.
To the solution was slowly added 0.2 mmol of 1-(tributyl-
stannyl)-2,3,3,4,4,5,5-heptafluorocyclopentene (5-Sn) in THF
(1 mL) via a syringe at 0 ꢁC. The whole mixture was stirred
at reflux temperature for 2 h. After stirring for 2 h, the resultant
mixture was filtered on Celite and concentrated in vacuo. Col-
umn chromatography of the residue using pentane gave pure
product, 1-benzyl-2,3,3,4,4,5,5-heptafluorocyclopentene 9k
(0.023 g, 41%). The products 9q and 9r could not be isolated
as a pure product due to their low boiling point and volatility.
5.3.10. 1-(2,3,3,4,4,5,5-Heptafluorocyclopenten-1-yl)-1-
methyl-3-phenyl-2-propen-1-ol (7j)
1H NMR (CDCl3) d 1.77 (s, 3H), 2.42 (br s, 1H), 6.36 (d,
J¼16.0 Hz, 1H), 6.73 (d, J¼16.0 Hz, 1H), 7.25e7.41 (m,
5H); 19F NMR (CDCl3) d ꢀ131.09 (br s, 2F), ꢀ126.79 to
ꢀ126.65 (m, 1F), ꢀ120.15 (dd, J¼261.0, 17.3 Hz, 1F),
ꢀ119.42 (dd, J¼261.0, 17.3 Hz, 1F), ꢀ107.82 (dd, J¼258.7,
12.4 Hz, 1F), 107.05 (dd, J¼258.7, 12.4 Hz, 1F).
5.5.1. 1-(4-Methoxybenzyl)-2,3,3,4,4,5,5-heptafluorocyclo-
pentene (9n)
1H NMR (CDCl3) d 3.62 (br s, 2H), 3.80 (s, 3H), 6.87 (AB
q, J¼8.6 Hz, 2H), 7.14 (AB q, J¼8.6 Hz, 2H); 13C NMR
(CDCl3) d 26.37, 55.25, 110.19 (tquint.d, J¼278.0, 24.1,
4.8 Hz), 110.83 (tt, J¼258.4, 22.9 Hz), 114.379, 115.54 (ttdt,
J¼282.3, 24.7, 10.9, 2.8 Hz), 123.80 (tq, J¼26.3, 6.0 Hz),
125.819, 129.761, 151.5e155.5 (dm, J¼295.5 Hz), 159.90;
19F NMR (CDCl3) d ꢀ134.4 to ꢀ134.3 (m, 1F), ꢀ130.60 (s,
2F), ꢀ119.247 (br s, 1F), ꢀ119.217 (br s, 1F), ꢀ111.090 (br
s, 1F), ꢀ111.064 (br s, 1F); IR (neat) 3004, 2937, 2840,
1714, 1613, 1515, 1382, 1252, 1202, 1150 cmꢀ1; HRMS
(FAB) found: m/z (Mþ) 314.0548, calcd for C13H9F7O:
314.0542.
5.4. Typical procedure for Pd(0)-catalyzed cross-coupling
reaction of 5-Sn with benzyl chloroformate
A 30 mL two-necked round-bottomed flask equipped with
a magnetic stirrer bar, a rubber septum, and an inlet tube
for argon was charged with a solution of 10 mol % of
Pd2(dba)3$CHCl3 (0.021 g, 0.02 mmol), 20 mol % of dppf
(0.022 g, 0.04 mmol), benzyl chloroformate (8k, 0.075 g,
0.44 mmol), 5 mol % of CuI (0.002 g, 0.01 mmol) in THF.
To the solution was slowly added 0.241 g of 1-(tributyl-
stannyl)-2,3,3,4,4,5,5-heptafluorocyclopentene (5-Sn, 0.2 mmol,
40 wt % solution) in THF (1 mL) via a syringe at 0 ꢁC. The
whole mixture was stirred at reflux temperature for 2 h. After
stirring for 2 h, the reaction mixture was filtered on Celite and
concentrated in vacuo. Column chromatography of the residue
using pentane gave pure product, 1-benzyl-2,3,3,4,4,5,5-hepta-
fluorocyclopentene 9k. The allylated product 9l could not be
isolated as a pure product due to the low boiling point and
volatility. 19F NMR of 9l was as follows: d (CDCl3) ꢀ134.25
to ꢀ134.22 (m, 1F), ꢀ130.65 (br s, 2F), ꢀ119.38 (br s, 2F),
ꢀ111.33 (br s, 2F).
5.5.2. 1-(4-Methylbenzyl)-2,3,3,4,4,5,5-heptafluorocyclo-
pentene (9o)
1H NMR (CDCl3) d 2.34 (s, 3H), 3.64 (br s, 2H), 7.11 (AB
q, J¼8.0 Hz, 2H), 7.15 (AB q, J¼8.0 Hz, 2H); 13C NMR
(CDCl3) d 21.03, 26.78, 110.21 (tquint.d, J¼275.2, 25.6,
4.9 Hz), 110.94 (tqd, J¼258.6, 22.4, 1.6 Hz), 115.54 (ttdt,
J¼260.3, 24.0, 11.5, 3.3 Hz), 123.69 (tq, J¼26.4, 5.8 Hz),
128.54, 129.68, 130.87, 137.33, 151.1e155.2 (dm,
J¼293.5 Hz); 19F NMR (CDCl3) d ꢀ134.1 to ꢀ134.0 (m,
1F), ꢀ130.60 (s, 2F), ꢀ119.28 (br s, 1F), ꢀ119.24 (br s,
1F), ꢀ111.08 (br s, 1F), ꢀ111.05 (br s, 1F); IR (neat) 2927,
1715, 1517, 1382, 1326, 1289, 1203, 1152 cmꢀ1; HRMS
(EI) found: m/z (Mþ) 298.0598, calcd for C13H9F7: 298.0592.
5.4.1. 1-Benzyl-2,3,3,4,4,5,5-heptafluorocyclopentene (9k)
1H NMR (CDCl3) d 3.68 (s, 2H), 7.25e7.29 (m, 2H),
7.28e7.30 (m, 1H), 7.35e7.45 (m, 2H); 13C NMR (CDCl3)
d 27.13, 110.34 (tquint.d, J¼274.8, 24.5, 4.4 Hz), 110.96 (tq,
J¼259.2, 23.3 Hz), 115.65 (ttd, J¼261.3, 9.9, 3.5 Hz),
123.60 (ttd, J¼25.9, 5.7, 5.7 Hz), 127.62, 128.70, 129.04,
134.05, 152.0e154.9 (dm, J¼299.7 Hz); 19F NMR (CDCl3)
d ꢀ133.8 to ꢀ133.7 (m, 1F), ꢀ130.59 (s, 2F), ꢀ119.3 (s,
1F), ꢀ119.2 (s, 1F), ꢀ111.1 (s, 1F), ꢀ111.0 (s, 1F); IR
(neat) 3036, 2931, 1716, 1605, 1497, 1456, 1383, 1151,
755 cmꢀ1; HRMS (FAB) found: m/z 284.0425, calcd for
(Mþ) C12H7F7: 284.0436.
5.5.3. 1-(4-Cyanobenzyl)-2,3,3,4,4,5,5-heptafluorocyclo-
pentene (9p)
1H NMR (CDCl3) d 4.60 (br s, 2H), 7.50 (AB q, J¼8.0 Hz,
2H), 7.66 (AB q, J¼8.0 Hz, 2H); 19F NMR (CDCl3) d ꢀ132.0
to ꢀ131.9 (m, 1F), ꢀ130.49 (s, 2F), ꢀ119.31 (br s, 1F),
ꢀ119.27 (br s, 1F), ꢀ110.82 (br s, 1F), ꢀ110.79 (br s, 1F);
IR (neat) 2944, 2254, 2232, 1383, 1267, 1154 cmꢀ1; HRMS
(FAB) found: m/z (MþH) 310.0485, calcd for C13H7F7N:
310.0467.

4222
S. Yamada et al. / Tetrahedron 64 (2008) 4215e4223
895e901; (f) Irie, M. Chem. Rev. 2000, 100, 1685e1716; (g) Organo-
fluorine Compounds, Chemistry and Applications; Hiyama, T., Ed.;
Springer: New York, NY, 2000; (h) Ojima, I.; McCarthy, J. R.; Welch,
J. T. Biomedical Frontiers of Fluorine Chemistry; American Chemical
Society: Washington, DC, 1996.
5.5.4. 1-(2-Furyl)-2,3,3,4,4,5,5-heptafluorocyclo-
pentene (9q)
1H NMR (CDCl3) d 3.72 (br s, 2H), 6.19 (d, J¼2.8 Hz, 1H),
6.33 (dd, J¼2.8, 2.4 Hz, 1H), 7.37 (d, J¼2.4 Hz, 1H); 19F
NMR (CDCl3) d ꢀ134.8 to ꢀ132.8 (m, 1F), ꢀ130.67 (s,
2F), ꢀ119.55 (br s, 1F), ꢀ119.51 (br s 1F), ꢀ111.97 (br s,
1F), ꢀ111.94 (br s, 1F); HRMS (EI) found: m/z (Mþ)
274.0218, calcd for C10H5F7O: 274.0229.
2. (a) Enantiocontrolled Synthesis of Fluoro-Organic Compounds;
Soloshonok, V. A., Ed.; Wiley: Chichester, UK, 1999; (b) Experimental
Methods in Organic Fluorine Chemistry; Kitazume, T., Yamazaki, T.,
Eds.; Kodansha: Tokyo, 1998; (c) Qiu, X.; Meng, W.; Qing, F.-L. Tetra-
hedron 2004, 60, 6711e6745; (d) Mikami, K.; Itoh, Y.; Yamanaka, M.
Chem. Rev. 2004, 104, 1e16; (e) Ichikawa, J.; Wada, Y.; Fujiwara, M.;
Sakoda, K. Synthesis 2002, 1917e1936.
3. (a) Morimitsu, K.; Kobatake, S.; Nakamura, S.; Irie, M. Chem. Lett. 2003,
32, 858e859; (b) Yagi, K.; Irie, M. Chem. Lett. 2003, 32, 848e849; (c)
Peters, A.; Vitols, C.; McDonald, R.; Branda, N. R. Org. Lett. 2003, 5,
1183e1185; (d) Kaieda, K.; Kobatake, S.; Miyasaka, H.; Murakami,
M.; Iwai, N.; Nagata, Y.; Itaya, A.; Irie, M. J. Am. Chem. Soc. 2002,
124, 2015e2024; (e) Malval, J. P.; Gosse, I.; Morand, J. P.; Lapouyade,
R. J. Am. Chem. Soc. 2002, 124, 904e905; (f) Takeshita, M.; Irie, M.
Tetrahedron Lett. 1999, 40, 1345e1348; (g) Ire, M.; Sakemura, K.;
Okinaka, M.; Uchida, K. J. Org. Chem. 1995, 60, 8305e8309.
4. For selected reports on the reaction of perfluorocyclopentene or the 1,2-
dichloro-analogue with oxygen-nucleophiles, see: (a) Lindner, P. E.;
Lemal, D. M. J. Org. Chem. 1996, 61, 5109e5115; (b) Bayliff, A. E.;
Bryee, M. R.; Chambers, R. D. J. Chem. Soc., Perkin Trans. 1 1987,
763e767; (c) Stockel, R. F.; Beachem, M. T.; Megson, F. H. J. Org.
Chem. 1965, 30, 1629e1632; (d) Sockel, R. F.; Beachem, M. T.; Megson,
F. H. Can. J. Chem. 1964, 42, 2880e2883.
5.5.5. 1-(2-Thienyl)-2,3,3,4,4,5,5-heptafluorocyclo-
pentene (9r)
1H NMR (CDCl3) d 3.89 (br s, 2H), 6.91e6.94 (m, 1H),
6.97 (dd, J¼5.6, 3.2 Hz, 1H), 7.23 (dd, J¼5.2, 1.2 Hz, 1H);
19F NMR (CDCl3) d ꢀ132.8 to ꢀ132.5 (m, 1F), ꢀ130.67 (s,
2F), ꢀ119.51 (br s, 1F), ꢀ119.47 (br s, 1F), ꢀ111.33 (br s,
1F), ꢀ111.30 (br s, 1F); HRMS (EI) found: m/z (Mþ)
289.9994, calcd for C10H5F7S: 290.0000.
5.5.6. 1-((E)-3-Phenyl-2-propen-1-yl)-2,3,3,4,4,5,5-hepta-
fluorocyclopentene (9s)
1H NMR (CDCl3) d 3.28 (d, J¼5.2 Hz, 2H), 6.13 (dt, J¼15.6,
5.2 Hz, 1H), 6.57 (d, J¼15.6 Hz, 1H), 7.23e7.40 (m, 5H); 13
C
NMR (CDCl3) d 24.81, 110.18 (tquint.d, J¼275.2, 25.6,
4.9 Hz), 110.82 (tqd, J¼258.7, 24.8, 1.7 Hz), 115.60 (tqt,
J¼260.3, 10.8, 2.5 Hz), 120.65, 122.78 (tq, J¼25.6, 5.8 Hz),
126.38, 128.03, 128.66, 134.43, 136.13, 151.2e155.5 (dm,
J¼307.4 Hz); 19F NMR (CDCl3) d ꢀ134.1 to ꢀ133.5 (m, 1F),
ꢀ130.50 (s, 2F), ꢀ119.25 (br s, 1F), ꢀ119.21 (br s, 1F),
ꢀ111.16 (br s, 1F), ꢀ111.13 (br s, 1F); IR (neat) 3030, 1715,
1449, 1384, 1298, 1203, 1151, 1118 cmꢀ1; HRMS (FAB)
found: m/z (Mþ) 310.0587, calcd for C14H9F7: 310.0592.
5. For selected reports on the reaction of perfluorocyclopentene or the 1,2-di-
chloro-analogue with sulfur-nucleophiles, see: (a) Matsui, M.; Tsuge, M.;
Funabiki, K.; Shibata, K.; Muramatsu, H.; Hirota, K.; Hosoda, M.; Tai, K.;
Shiozaki, H.; Kim, M.; Nakatsu, K. J. Fluorine Chem. 1999, 97, 207e212;
(b) Mir, Q.; Shreeve, J. M. J. Fluorine Chem. 1994, 68, 269e275.
6. For selected reports on the reaction of perfluorocyclopentene or the 1,2-
dichloro-analogue with nitrogen-nucleophiles, see: (a) Mir, Q.; Guo, C.;
Kirchmeier, R. L.; Shreeve, J. M. J. Org. Chem. 1994, 59, 173e177;
(b) Cullen, W. R.; Dhaliwal, P. S. Can. J. Chem. 1967, 45, 719e724;
(c) McBee, E. T.; Turner, J. J.; Morton, C. J.; Stefani, A. P. J. Org.
Chem. 1965, 30, 3698e3705.
5.5.7. 1-(3-Phenyl-2-propyn-1-yl)-2,3,3,4,4,5,5-heptafluoro-
cyclopentene (9t)
7. For selected reports on the reaction of perfluorocyclopentene or the 1,2-
dichloro-analogue with phosphorus-nucleophiles, see: (a) Su, D.; Guo,
C.; Willett, D.; Scott, B.; Kirchmeier, R. L.; Shreeve, J. M. J. Am.
Chem. Soc. 1990, 112, 3152e3155; (b) Stockel, R. F. Can. J. Chem.
1968, 46, 2625e2628; (c) Frank, A. W. J. Org. Chem. 1966, 31,
917e921.
1H NMR (CDCl3) d 5.44 (s, 2H), 7.25e7.28 (m, 2H), 7.30e
7.40 (m, 3H); 13C NMR (CDCl3) d 80.49, 94.43, 94.45, 110.08
(tquint.d, J¼274.5, 24.0, 5.0 Hz), 110.63 (tqd, J¼258.7, 22.3,
2.5 Hz), 115.03 (ttdt, J¼259.6, 24.0, 7.4, 3.2 Hz), 119.61 (tq,
J¼24.0, 4.2 Hz), 127.11, 128.36, 128.77, 131.76, 149.5e
153.5 (dm, J¼300.0 Hz); 19F NMR (CDCl3) d ꢀ130.80 (s,
2F), ꢀ125.1 to ꢀ124.7 (m, 1F), ꢀ119.04 (br s, 1F), ꢀ119.00
(br s, 1F), ꢀ109.94 (br s, 1F), ꢀ109.91 (br s, 1F); IR (neat)
3064, 1925, 1682, 1451, 1384, 1203, 1151, 997 cmꢀ1; HRMS
(EI) found: m/z (Mþ) 308.0431, calcd for C14H7F7: 308.0436.
8. Yamada, S.; Konno, T.; Ishihara, T.; Yamanaka, H. J. Fluorine Chem.
2005, 126, 125e133.
9. Yamada, S.; Ishii, E.; Konno, T.; Ishihara, T. Org. Biomol. Chem. 2007, 5,
1442e1449.
10. (a) Marshall, J. A.; Garofalo, A. W.; Hinkle, K. W. Org. Synth. Coll. Vol.
2004, 10, 496; Marshall, J. A.; Garofalo, A. W.; Hinkle, K. W. Org. Synth.
2000, 77, 98e106; (b) Tsuji, Y. Synthesis of Organic Compounds VI; Ko-
tani, M., Ed.; The Fifth Series of Experimental Chemistry; Maruzen:
2004; Vol. 18; (c) Frey, O.; Hoffmann, M.; Kessler, H.; Uhlmann, P.;
Vasella, A. Helv. Chim. Acta 1994, 77, 2060e2069.
Acknowledgements
11. (a) Lipshutz, B. H.; Sharma, S.; Reuter, D. C. Tetrahedron Lett. 1990, 31,
7253e7256; (b) Lipshutz, B. H.; Wilhelm, R. S.; Kozlowski, J. A. J. Org.
Chem. 1984, 49, 3938e3942.
The authors are grateful to Zeon Corporation for supplying
the starting material, perfluorocyclopentene (1).
12. Lipshutz, B. H. Organometallics in Synthesis: A Manual; Schlosser, M.,
Ed.; John Wiley and Sons: New York, NY, 2002.
13. For related reports on coupling reaction of fluorinated vinylmetal species
References and notes
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