Fluorination with ionic liquid EMIMF(HF)2.3 as mild HF source

Article abstract of DOI:10.1016/j.jfluchem.2005.09.016

Hydrogen fluoride is a basic fluorinating reagent, but handling it is difficult. For this reason, some modified fluorinating reagents such as HF-pyridine, Et₃N-HF, and poly(hydrogen fluoride) complex have been developed. Those reagents, however, still require aqueous work-up procedures which generate hydrogen fluoride. Recently, ionic liquids have received much attention because of the ease in handling them and the possibility of non-aqueous work-up. An ionic liquid, 3-ethyl-1-methyimidazolium oligo hydrogen fluoride (EMIMF(HF)_2.3), which is stable in air and moisture, can be used as a hydrogen fluoride equivalent for some fluorination reactions; it does not require an aqueous work-up.

Full text of DOI:10.1016/j.jfluchem.2005.09.016

Journal of Fluorine Chemistry 127 (2006) 29–35
www.elsevier.com/locate/fluor
Fluorination with ionic liquid EMIMF(HF)2.3 as mild HF source
Hideaki Yoshino a, Kazuhiko Matsumoto b, Rika Hagiwara b, Yasuhiko Ito b,
Koichiro Oshima a, Seijiro Matsubara a,
*
a Department of Material Chemistry, Graduate School of Engineering, Kyoto University,
Kyoutodaigaku-Katsura, Nishikyo, Kyoto 615-8510, Japan
b Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University,
Yoshida hon-machi, Sakyo, Kyoto 606-8501, Japan
Received 15 July 2005; accepted 26 September 2005
Available online 6 December 2005
Abstract
Hydrogen fluoride is a basic fluorinating reagent, but handling it is difficult. For this reason, some modified fluorinating reagents such as HF-
pyridine, Et3N-HF, and poly(hydrogen fluoride) complex have been developed. Those reagents, however, still require aqueous work-up procedures
which generate hydrogen fluoride. Recently, ionic liquids have received much attention because of the ease in handling them and the possibility of
non-aqueous work-up. An ionic liquid, 3-ethyl-1-methyimidazolium oligo hydrogen fluoride (EMIMF(HF)2.3), which is stable in air and moisture,
can be used as a hydrogen fluoride equivalent for some fluorination reactions; it does not require an aqueous work-up.
# 2005 Elsevier B.V. All rights reserved.
Keywords: Ionic liquid; Hydrogen fluoride; Halofluorination; Fluorohydrin
1. Introduction
phase can be easily isolated by decantation. Ionic liquid 3-ethyl-
1-methy-imidazolium oligo hydrogen fluoride (EMIMF(HF)2.3),
which is stable in air and moisture, might be used as such a
reaction medium with a hydrogen fluoride source.
Organofluorine compounds have received much attention
because of their interesting chemical and physical properties or
biological activities [1]. Introduction of a fluorine atom into
organicmolecules dramatically changes such physicalproperties
and biological activities. Thus, a development of convenient and
efficient fluorinating methods has been desired. Hydrogen
fluoride is the most basic nucleophilic fluorinating reagent [2],
but it has a drawback due to difficulties in its handling. HF-
pyridine (Olah’s reagent) [3], Et3N-HF [4], and poly(hydrogen
fluoride) complex [5] are available as alternative stable hydrogen
fluoride sources. Those reagents, however, still require an
aqueous work-up which generates hydrogen fluoride. Recently,
ionic liquids have attracted much attention as reaction media
because of the possibility of non-aqueous work-up, especially in
the field of green chemistry and combinatorial chemistry [6].
Ionic liquids are not miscible with organic solvents, and form
biphase systems. After the reaction, the products in the organic
2. Results and discussion
2.1. EMIMF(HF)2.3 (EMI: 1-ethyl-3-methylimidazolium, 1)
EMIMF(HF)2.3 (1) was prepared by a direct reaction of 1-
ethyl-3-methylimidazolium chloride and anhydrous hydrogen
fluoride according to the reported procedure [7]. This ionic
liquid is stable against moisture and air. It consists of 1-ethyl-3-
methylimidazolium cation and F(HF)2.3 anion. In the F(HF)2.3
anion, a rapid exchange of HF between F(HF)2 anion and
F(HF)3 anion occurs (Fig. 1). The value ‘‘2.3’’ was decided by
the results of elemental analysis.
2.2. Halofluorination of alkenes with EMIMF(HF)2.3 (1)
We examined the halofluorination of 1-dodecene using this
ionic liquid as shown in Table 1 [8]. Reactions were carried out
in tall polypropylene tubes that are easy to handle for
decantation in the work-up process. To a mixture of substrate
* Corresponding author. Tel.: +81 75 383 2441; fax: +81 75 383 2438.
E-mail address: matsubar@orgrxn.mbox.media.kyoto-u.ac.jp
(S. Matsubara).
0022-1139/$ – see front matter # 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jfluchem.2005.09.016

30
H. Yoshino et al. / Journal of Fluorine Chemistry 127 (2006) 29–35
Table 2
lodofluorination of alkenes
Fig. 1. EMIMF(HF)2.3
.
Entry
1
Alkene
Time (h)
3
Product
Yield (%)
90
Table 1
lodofluorination of 1-dodecene
2
1
91
3
4
5
1
1
1
95
98
70
Entry
NIS (eq.)
Temperature (8C)
Time (h)
Yield (%)
2a
3a
3b
1
1
1
2
2
25
25
25
60
3
36
3
60
30
7
38
67
90
87
–
–
2
7
2
3
4a
1
5
a
Solvent, CICH2CH2Cl.
6
7
1
1
88
78
dissolved in CH2Cl2, ionic liquid was added to form a biphase
(Fig. 2A). To the resulting mixture, N-iodosuccinimide (NIS)
was added in several portions. The mixture gradually became
first clear and then yellow (Fig. 2B and C). When the reaction
was finished, hexane was added to the reaction mixture. The
resulting mixture became a biphase (Fig. 2D). Decantation of
the upper phase gave a hexane solution of the produced b-
halofluoride. After the solution was passed through a short
silica-gel column, it was concentrated in vacuo to obtain the
products. In this procedure, no aqueous was included. When
one equivalent of NIS was used, 30% of starting material was
recovered in spite of the longer reaction time (Table 1, Entries 1
and 2). The reaction proceeded smoothly by employing two
equivalents of NIS (Entry 3). Furthermore, the reaction was
accelerated by heating at 60 8C, but regioselectivity was
decreased (Entry 4). From these results, we employed the
condition in Entry 3.
As shown in Scheme 1, chlorofluorination of alkenes with N-
chlorosuccinimide (NCS) and the ionic liquid 1 was also
examined. The products were not obtained in good yield and
most of the starting alkene was recovered, although a longer
reaction time compared to those needed for the bromo- and
iodoalkenation was required.
2.3. Ring opening fluorination of epoxides [9]
Various alkenes were iodofluorinated as shown in Table 2.
In all cases, products were obtained in good yields and with
high regioselectivity.
To styrene oxide (6a) in CH2Cl2 was added EMIMF(HF)2.3
(1) at room temperature and the mixture was stirred vigorously
to obtain 2-fluoro-2-phenyl-ethanol (7a) in 72% yield (Table 4,
Entry 1). The reaction mixture is a biphase that consists of
CH2Cl2 phase and ionic liquid phase. In this reaction, the regio
isomer 1-fluoro-2-phenyl-2-ethanol was not detected by 1H and
Bromofluorination of alkenes was also performed with
N-bromosuccinimide (NBS) and the ionic liquid 1. Results are
summarized in Table 3. vic-Bromofluoroalkanes 4 were also
obtained in good yields.
Fig. 2. lodofluorination of alkenes with EMIMF(HF)2.3
.

H. Yoshino et al. / Journal of Fluorine Chemistry 127 (2006) 29–35
31
Table 3
Table 4
Bromofluorination of alkenes
Ring opening fluorination of styrene oxide
´
Entry
1
Alkene
Time (h)
3
Product
Yield (%)
86
Entry
Solvent
CH2CI2
Time (h)
7a (%)
7a (%)
1
24
16
12
4
72
81
74
4
–
2
3
4
CH2CI2/0.1 eq. MeOH
CH2CI2/1.0 eq. MeOH
MeOH
–
17
75
2
1
90
3
4
5
1
1
1
90
95
81
2.4. Deprotection of silyl ether
A silyl group is one of the most useful protecting groups for
a hydroxy group [10]. Silyl ethers are readily cleaved by mild
acidic hydrolysis [11] or by a fluoride ion generated by TBAF
[12]. Hydrogen fluoride (4% solution of 95% HF aq. in CH3CN)
is also useful as a mild reagent [13]. Ionic liquid 1 should be
Table 5
6
7
1
1
87
93
Ring opening flouorination of various epoxides
Entry Epoxide
Time Product
(h)
Yield
(%)
1
16
81
19F NMR in the obtained crude product. An addition of
catalytic amount of methanol increased the rate of the reaction.
Increasing the amount of methanol resulted in the formation of
methoxyalkanol 7a0 which was formed by acid-catalyzed ring
opening of epoxide with methanol (Entries 3 and 4).
2
3
16
16
74
55
Ring opening fluorinations of various epoxides with
EMIMF(HF)2.3 and methanol catalyst are summarized in
Table 5. In all cases, the high regioselectivity was observed. An
epoxide of terminal mono substituted alkene (6h) was
recovered even for the longer reaction period.
4
5
6
65
24
37a
6
7
24
48
28b
7c
8
120
–
0d
a
50% of starting material was recovered.
47% of starting material was recovered.
83% of starting material was recovered.
Starting material was only recovered.
b
c
d
Scheme 1.

32
H. Yoshino et al. / Journal of Fluorine Chemistry 127 (2006) 29–35
Table 6
m, multiplet), coupling constant (Hz), and integration. Data for
13C NMR are reported as chemical shifts. High resolution mass
spectra were generated by JEOL Mstation 700 spectrometer.
The elemental analyses were carried out at the Elemental
Analysis Center of Kyoto University.
Deprotection of silyl ethers
5. General procedure for halofluorination
Entry
Protected alcohol
Time
(h)
Product
Yield
(%)
In a 15 ml polypropylene tube, CH2Cl2 (500 ml) solution of
alkene (1.0 mmol) and EMIMF(HF)2.3 (1, 600 ml) were placed
and stirred with magnetic stirrer vigorously. To this reaction
mixture, N-halosuccinimide (2.0 mmol) was added in several
portions at room temperature. When the reaction finished,
hexane (1 ml) was added and the whole was stirred vigorously.
After the stirring was stopped, the mixture had separated into
two phases. The upper layer was collected by decantation. This
extraction with hexane was repeated twice more. The
combined hexane layers were concentrated in vacuo. The
crude product was purified by short silica-gel column
chromatography.
1
2
0.5
1.5
99
99
3
4
5
1
2
1
76
94
90
6
1
93
5.1.1. 2-Fluoro-1-iodododecane (3a) [15]
useful as mild desilylating reagent as shown in Table 6. To a
catalytic amount of methanol and EMIMF(HF)2.3, 1-trimethyl-
siloxyheptene (8a) in CH2Cl2 was added at room temperature
and the mixture was stirred to obtain 1-hexanol (9a) in 99%
yield. Alkynyl silane, which is cleaved by TBAF or KF [14],
was not affected in this condition (Entry 4). THP ether was not
cleaved in this condition (Entry 5). Mono alkyl substituted
epoxide was tolerated during desilylation, whereas the ring
opening oligomerization proceeded under treatment of 8f with
hydrogen fluoride aq. methanol solution.
1H NMR (300 MHz, CDCl3): d 4.41 (ddt, J = 48.0, 10.8,
1.5 Hz, 1H), 3.31 (ddd, J = 20.1, 5.7, 2.1 Hz, 2H), 1.80–1.65
(m, 2H), 1.45–1.20 (m, 14H), 0.88 (t, J = 6.9 Hz, 3H). 19F NMR
(282 MHz, CDCl3): d ꢀ170.6 (m).
5.1.2. 2-Fluoro-1-iodo-2-methyldodecane (3b)
1H NMR (300 MHz, CDCl3): d 3.34 (d, J = 16.8 Hz, 2H),
1.83–1.72 (m, 2H), 1.49 (d, J = 21.0 Hz, 3H), 1.40–1.20 (m,
16H), 0.88 (t, J = 6.9 Hz, 3H). 13C NMR (75 MHz, CDCl3): d
94.7 (d, J = 172.3 Hz), 39.3 (d, J = 22.0 Hz), 32.2, 30.0, 29.9,
29.8, 29.7, 29.6, 24.7 (d, J = 24.4 Hz), 23.9, 23.8, 22.9, 14.4,
13.8 (d, J = 27.3 Hz). 19F NMR (282 MHz, CDCl3): d ꢀ140.0
(m). Anal. calcd. for C13H26FI: C, 47.57; H, 7.98. Found: C,
47.54; H, 7.70.
3. Conclusion
We demonstrated the possibilities of an ionic liquid, 3-ethyl-
1-methyimidazolium oligo hydrogen fluoride (EMIMF(HF)2.3)
(1), toactas astableand useful substituteforhydrogenfluoridein
fluorination of organiccompounds. Althoughthe availabilityof1
is a still a limitation of these transformation, the high reactivity
and the ease of the procedure will compensate the difficulty.
5.1.3. 1-Fluoro-2-iodocyclohexane (3c) [15]
1H NMR (300 MHz, CDCl3): d 4.52 (ddt, J = 47.7, 8.7,
4.5 Hz, 1H), 4.16–4.06 (m, 1H), 2.44–2.30 (m, 1H), 2.28–2.13
(m, 1H), 2.02–1.78 (m, 2H), 1.66–1.54 (m, 2H), 1.50–1.24 (m,
2H). 19F NMR (282 MHz, CDCl3): d ꢀ159.5 (m).
4. Experimental
All solvents were used as obtained from commercial
suppliers. Chromatographic purification of products was
accomplished using forced-flow chromatography on Kanto
Chemical Co., Inc. Silica-gel 60 N (spherical, neutral). The
polypropylene tube used was a centrifuge tube (15 ml) with a
screw cap, and is available from Corning. EMIMF(HF)2.3 was
5.1.4. 1-Fluoro-2-iodo-1-methylcyclohexane (3d) [15]
1H NMR (300 MHz, CDCl3): d 4.37 (dt, J = 8.1, 4.2 Hz,
1H), 2.30–2.08 (m, 2H), 2.00–1.87 (m, 1H), 1.82–1.62 (m, 3H),
1.56 (d, J = 22.2 Hz, 3H), 1.54–1.40 (m, 2H). 19F NMR
(282 MHz, CDCl3): d ꢀ132.4 (m).
1
prepared according to the literature [7]. H, 13C, 19F NMR
spectra were recorded on Varian Mercury (300, 75 and
282 MHz, respectively) instruments and are internally refer-
5.1.5. 1-Fluoro-2-iodo-1-phenylethane (3e) [15]
1
enced to residual solvent signals (for H and 13C) and CFCl3
1
(for 19F). Data for H NMR are reported as chemical shifts
1H NMR (300 MHz, CDCl3): d 7.50–7.30 (m, 5H), 5.53
(ddd, J = 46.5, 7.2, 4.8 Hz, 1H), 3.55–3.41 (m, 2H). 19F
(d ppm), multiplicity (s, singlet; d, doublet; t, triplet; q, quartet;

H. Yoshino et al. / Journal of Fluorine Chemistry 127 (2006) 29–35
33
NMR (282 MHz, CDCl3): d ꢀ166.4 (ddd, J = 46.5, 23.7,
5.1.13. 1-Bromo-2-fluoro-2-phenylpropane (4f) [17]
17.8 Hz).
1H NMR (300 MHz, CDCl3): d 7.43–7.32 (m, 5H), 3.73–
3.60 (m, 2H), 1.84 (d, J = 22.2 Hz, 3H). 19F NMR (282 MHz,
CDCl3): d ꢀ147.5 (ddq, J = 22.2, 22.2, 18.4 Hz).
5.1.6. 2-Fluoro-1-iodo-2-phenylpropane (3f) [15]
1H NMR (300 MHz, CDCl3): d 7.50–7.30 (m, 5H), 3.59 (d,
J = 20.4 Hz, 2H), 1.86 (d, J = 21.6 Hz, 3H). 19F NMR
(282 MHz, CDCl3): d ꢀ142.4 (tq, J = 21.6, 20.4 Hz).
5.1.14. 2-Bromo-1-fluoro-1-(4-methylphenyl)ethane (4g)
[18]
5.1.7. 1-Fluoro-2-iodo-1-(4-methylphenyl)ethane (3g)
1H NMR (300 MHz, CDCl3): d 7.38–7.18 (m, 4H), 5.57
(ddd, J = 46.8, 8.1, 4.2 Hz, 1H), 3.75–3.53 (m, 2H), 2.37 (s,
3H). 19F NMR (282 MHz, CDCl3): d ꢀ172.3 (ddd, J = 46.8,
25.9, 18.9 Hz).
1H NMR (300 MHz, CDCl3): d 7.28–7.15 (m, 4H), 5.52
(ddd, J = 45.3, 18.6, 6.3 Hz, 1H), 3.55–3.40 (m, 2H), 2.37 (s,
3H). 13C NMR (75 MHz, CDCl3): d 139.3, 135.1 (d,
J = 20.5 Hz), 129.6, 125.8 (d, J = 6.2 Hz), 93.4 (d,
J = 175.5 Hz), 21.7, 7.9 (d, J = 28.8 Hz). 19F NMR
(282 MHz, CDCl3): d ꢀ164.6 (ddd, J = 45.4, 23.7, 15.8 Hz).
Anal. calcd. for C9H10FI: C, 40.93; H, 3.82. Found: C, 40.66; H,
3.69.
5.1.15. 2-Chloro-1-fluoro-1-phenylethane (5b) [19]
1H NMR (300 MHz, CDCl3): d 7.51–7.38 (m, 5H), 5.60
(ddd, J = 47.4, 8.1, 3.9 Hz, 1H), 3.86–3.69 (m, 2H). 19F
NMR (282 MHz, CDCl3): d ꢀ178.4 (ddd, J = 47.4, 23.7,
15.8 Hz).
5.1.8. 1-Bromo-2-fluorododecane (4a) [16]
5.1.16. 1-Chloro-2-fluoroundecane (5h)
1H NMR (300 MHz, CDCl3): d 4.62 (dddt, J = 48.6, 7.5, 5.4,
5.4 Hz, 1H), 3.51 (ddd, J = 19.8, 10.8, 5.4 Hz, 2H), 1.77–1.64
(m, 2H), 1.49–1.26 (m, 16H), 0.88 (t, J = 6.8 Hz, 3H). 19F NMR
(282 MHz, CDCl3): d ꢀ178.0 (dddt, J = 48.6, 27.0, 19.8,
19.8 Hz).
1H NMR (300 MHz, CDCl3): d 4.60 (dddt, J = 48.0, 8.4, 4.8,
4.8 Hz, 1H), 3.62 (ddd, J = 20.1, 5.4, 1.2 Hz, 2H), 1.79–1.61
(m, 2H), 1.48–1.26 (m, 14H), 0.88 (t, J = 6.9 Hz, 3H). 13C
NMR (75 MHz, CDCl3): d 92.7 (d, J = 173.8 Hz), 46.1 (d,
J = 25.3 Hz), 32.7 (d, J = 20.0 Hz), 32.1, 29.8, 29.7, 29.6, 29.5,
29.4, 22.9, 14.4. 19F NMR (282 MHz, CDCl3): d ꢀ181.6 (m).
HRMS Found: m/z 208.1392. Calcd. for C11H22ClF: (M+)
208.1394.
5.1.9. 1-Bromo-2-fluoro-2-methyldodecane (4b)
1H NMR (300 MHz, CDCl3): d 3.46 (d, J = 15.9 Hz, 2H),
1.80–1.71 (m, 2H), 1.46 (d, J = 21.3 Hz, 3H), 1.39–1.26 (m,
16H), 0.88 (t, J = 7.2 Hz, 3H). 13C NMR (75 MHz, CDCl3): d
95.0 (d, J = 171.5 Hz), 38.6 (d, J = 29.3 Hz), 38.0 (d,
J = 21.9 Hz), 32.0, 29.8, 29.7, 29.6, 29.5, 29.4, 23.6 (d,
J = 23.9 Hz), 23.5, 23.4, 22.8, 14.2. 19F NMR (282 MHz,
CDCl3): d ꢀ144.9 (m). Anal. calcd. for C13H26FBr: C, 55.52;
H, 9.32. Found: C, 55.59; H, 9.13.
5.2. General procedure for ring opening fluorination of
epoxides
In a 15 mm polypropylene tube, epoxide (6, 1.0 mmol),
CH2Cl2 (500 ml), and methanol (4 ml) were placed. Ionic liquid
EMIMF(HF)2.3 (1, 600 ml) was added to the mixture at room
temperature, and the mixture stirred. When the reaction
finished, ethyl acetate (1 ml) was added and the whole was
stirred vigorously. After the stirring was stopped, the mixture
had separated into two phases. The upper layer was collected by
decantation. This extraction with ethyl acetate was repeated
twice more. The crude product was purified by short silica-gel
column chromatography. The yield was determined by 19F
NMR in comparison with an internal standard.
5.1.10. 1-Bromo-2-fluorocyclohexane (4c) [17]
1H NMR (300 MHz, CDCl3): d 4.48 (ddt, J = 48.0, 8.4,
4.5 Hz, 1H), 4.07–3.97 (m, 1H), 2.35–2.17 (m, 2H), 1.89–1.62
(m, 4H), 1.42–1.31 (m, 2H). 19F NMR (282 MHz, CDCl3): d
ꢀ167.4 (dm, J = 48.0 Hz).
5.1.11. 2-Bromo-1-fluoro-1-methylcyclohexane (4d) [17]
5.2.1. 2-Fluoro-2-phenylethanol (7a) [20]
1H NMR (300 MHz, CDCl3): d 4.20 (dt, J = 7.2, 3.9 Hz,
1H), 2.35–1.25 (m, 8H), 1.51 (d, J = 22.4, 3H). 19F NMR
(282 MHz, CDCl3): d ꢀ137.0 (m).
1H NMR (300 MHz, CDCl3): d 7.41–7.34 (m, 5H), 5.57
(ddd, J = 3.0, 7.5, 48.3 Hz, 1H), 4.01–3.76 (m, 2H), 2.02 (bs,
1H). 19F NMR (282 MHz, CDCl3): d ꢀ186.8 (ddd, J = 48.6,
29.6, 17.8 Hz).
5.1.12. 2-Bromo-1-fluoro-1-phenylethane (4e) [15]
5.2.2. 2-Fluoro-2-phenylpropanol (7b) [21]
1H NMR (300 MHz, CDCl3): d 7.51–7.35 (m, 5H), 5.50
(ddd, J = 46.8, 7.2, 4.2 Hz, 1H), 3.64–3.43 (m, 2H). 19F NMR
(282 MHz, CDCl3): d ꢀ174.1 (ddd, J = 46.8, 23.7, 16.5 Hz).
1H NMR (300 MHz, CDCl3): d 7.40–7.32 (m, 5H), 3.92–
3.69 (m, 2H), 1.83 (bs, 1H), 1.75 (d, J = 22.5 Hz, 3H). 19F NMR
(282 MHz, CDCl3): d ꢀ157.2 (m).

34
H. Yoshino et al. / Journal of Fluorine Chemistry 127 (2006) 29–35
5.2.3. 2-Fluorocyclohexanol (7c) [4b]
in DMF. 8f was prepared from 1-trimethylsiloxy-9-decene by
oxidation with 3-chloroperoxybenzoic acid.
1H NMR (300 MHz, CDCl3): d 4.21 (dm, J = 51.3 Hz, 1H),
3.67–3.57 (m, 1H), 2.45 (bs, 1H), 2.13–1.99 (m, 2H), 1.77–1.69
(m, 2H), 1.51–1.20 (m, 4H). 19F NMR (282 MHz, CDCl3): d
ꢀ181.4 (d, J = 51.3 Hz).
5.4.1. 6-(Trimethylsilyl)-5-hexyn-1-ol (9d) [23]
1H NMR (300 MHz, CDCl3): d 3.68 (t, J = 6.0, 2H), 2.27 (t,
J = 6.6 Hz, 2H), 1.72–1.56 (m, 2H), 0.14 (s, 9H).
5.2.4. 2-Fluoro-2-methylcyclohexanol (7d) [22]
1H NMR (300 MHz, CDCl3): d 3.76–3.67 (m, 1H), 2.17 (bs,
1H), 1.94–1.21 (m, 11H). 19F NMR (282 MHz, CDCl3): d
ꢀ142.0 (m).
5.4.2. 4O-(Tetrahydropyran-2-yl)-1-butanol (9e) [24]
1H NMR (300 MHz, CDCl3): d 4.61–4.56 (m, 1H), 3.89–
3.72 (m, 2H), 3.66 (t, J = 6.3 Hz, 2H), 3.54–3.41 (m, 2H), 1.68–
1.46 (m, 10H).
5.2.5. 2-Fluoro-2-methyl-3-decanol (7e)
1H NMR (300 MHz, CDCl3): d 3.55 (t, J = 7.5 Hz, 1H), 1.98
(s, 1H), 1.36 (d, J = 3.9 Hz, 6H), 1.35–1.24 (m, 14H), 0.88 (t,
J = 6.9 Hz, 3H). 13C NMR (75 MHz, CDCl3): d 98.5 (d,
J = 163.4 Hz), 77.2 (d, J = 23.3 Hz), 32.2, 31.6, 31.5, 30.0,
29.9, 24.2, 23.0, 21.3 (d, J = 24.5 Hz, 2C), 14.5. 19F NMR
(282 MHz, CDCl3): d ꢀ144.7 (m). Anal. calcd. for C12H25FO:
C, 70.54; H, 12.33. Found: C, 70.48; H, 12.28.
5.4.3. 9,10-Epoxy-1-decanol (9f) [25]
1H NMR (300 MHz, CDCl3): d 3.64 (t, J = 6.6 Hz, 2H),
2.93–2.88 (m, 1H), 2.75 (dd, J = 5.1, 5.1 Hz, 1H), 2.45 (dd,
J = 5.1, 5.1 Hz, 1H), 1.59–1.26 (m, 14H).
Acknowledgements
This work was supported financially by the Japan Ministry
of Education, Science, Sports, and Culture. The financial
support provided by Chugai Pharmaceutical Co., Ltd. and that
from Takahashi Industrial and Economical Research Founda-
tion are also acknowledged.
5.2.6. 2-Fluoro-2-methyldecanol (7f)
1H NMR (300 MHz, CDCl3): d 3.67–3.47 (m, 2H), 1.76–
1.56 (m, 2H), 1.36 (s, 3H), 1.34–1.22 (m, 12H), 0.88 (t,
J = 6.9 Hz, 3H). 13C NMR (75 MHz, CDCl3): d 98.0 (d,
J = 165.3 Hz), 68.43 (d, J = 23.4 Hz), 36.6 (d, J = 22.2 Hz),
32.2, 30.4, 29.8, 29.6, 23.8 (d, J = 6.3 Hz), 23.0, 21.1 (d,
J = 24.5 Hz), 14.5. 19F NMR (282 MHz, CDCl3): d ꢀ154.8 (m).
Anal. calcd. for C11H23FO: C, 69.43; H, 12.18. Found: C,
69.68; H, 11.88.
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