Facile synthesis of aryl- and alkyl-bis(trifluoromethylsulfonyl)methanes

Article abstract of DOI:10.1246/bcsj.78.1401

Various arylbis(trifluoromethylsulfonyl)methanes (1) have been synthesized by reacting the corresponding benzylic halides with sodium trifluoromethanesulfinate and then with triflic anhydride. In addition, when the aryl group of 1 is a pentafluorophenyl group, the nucleophilic para-substitution of the aryl group with alkyllithiums and sodium alkoxides occurs. This reaction is useful for the design of new Bronsted acids.

Full text of DOI:10.1246/bcsj.78.1401

ꢀ 2005 The Chemical Society of Japan
Bull. Chem. Soc. Jpn., 78, 1401–1410 (2005) 1401
BCSJ Award Article
Facile Synthesis of Aryl- and Alkyl-bis(trifluoromethylsulfonyl)methanes
ꢀ
ꢀ;1
Aiko Hasegawa, Takuo Ishikawa, Kazuaki Ishihara, and Hisashi Yamamoto
Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603
1Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, IL 60637, U. S. A.
Received February 10, 2005; E-mail: ishihara@cc.nagoya-u.ac.jp
Various arylbis(trifluoromethylsulfonyl)methanes (1) have been synthesized by reacting the corresponding benzyl-
ic halides with sodium trifluoromethanesulfinate and then with triflic anhydride. In addition, when the aryl group of 1 is a
pentafluorophenyl group, the nucleophilic para-substitution of the aryl group with alkyllithiums and sodium alkoxides
occurs. This reaction is useful for the design of new Brønsted acids.
The trifluoromethylsulfonyl (triflyl, Tf) group is one of the
strongest neutral electron-withdrawing groups.1 Triflic acid
PhI(OAc)2 + CH2Tf2
(71%)
(TfOH),2 bis(triflyl)imide (Tf2NH),3,4a and tris(triflyl)methane
benzene
(Tf3CH)4b,5 are known to be strong acids and effective cata-
ð2Þ
PhI=CTf2
1a
1a
lysts for various organic reactions. Their conjugate bases are
useful as counterions for strong Lewis acid catalysts such as
Me3SiOTf,6 Me3SiNTf2,4c,7 and Sc(CTf3)3.4b,8 However, it is
difficult to modify these acids, which is a disadvantage in
the design of a Brønsted acid or Lewis acid. Thus, we focused
on phenylbis(triflyl)methane (1a, pKa ¼ 7:83 in MeCN,9 12.5
in CD3CO2D10) because the steric and electronic effects of the
aromatic ring in arylbis(triflyl)methanes were expected to
greatly influence their Brønsted acidity and their catalytic ac-
tivity and selectivity for organic reactions. To the best our
knowledge, only two methods have been reported for the syn-
thesis of 1a: the reaction of benzylmagnesium chloride with
triflyl fluoride11a and the photochemical reaction of phenyl-
iodonium bis(triflyl)methanide with benzene11b give 1a in
yields of 40 and 61%, respectively (Eqs. 1 and 2).
The former method requires gaseous triflyl fluoride (bp ꢁ21
ꢂC), which is not commercially available, as an electrophilic
triflyl source, while the latter requires a large amount of benzene
as a solvent; upon photochemical reaction with arenes bearing
electron-withdrawing groups such as fluorobenzene, no corre-
sponding arylbis(triflyl)methanes are formed. Zhu et al. have re-
ported a new synthetic route to 1a.11c According to that report,
1a can be prepared in 73% yield by the pyrolysis of benzenedi-
azonium bis(triflyl)methanide. This synthetic route was very at-
tractive to us as a general method for the preparation of various
arylbis(triflyl)methanes. Unfortunately, however, we obtained
O-phenylation product in 71% yield instead of 1a (Eq. 3).12
UV
(61%)
PhN2Cl + KCHTf2
(95%)
Tf
Ph N2+ −HC
Tf
75-95 °C
no solvents
(76%)
ð3Þ
75 °C, 10 min
and then
95 °C , 2 min
CF3
O
CF3
S O-
O
S OPh
+N2 Ph
no solvents
(71%)
S O
CF3
Tf
O
We report here a practical and convenient two-step synthe-
sis of arylbis(triflyl)methanes and the design of Brønsted acids
using nucleophilic para-substitution for pentafluorophenyl-
bis(triflyl)methane.
Results and Discussion
This new process involves the preparation of benzyl tri-
fluoromethyl sulfone (3a) by the nucleophilic substitution of
benzyl bromide (2a) with sodium trifluoromethanesulfinate
(CF3SO2Na) and the subsequent reaction of the lithium salt
of 3a with triflic anhydride to give the desired compound 1a
(Scheme 1). The first step was accomplished by a slight mod-
ification of the method described by Hendrickson et al.1 al-
though the original procedure is not efficient when the aromat-
THF
2PhCH2MgCl + 2TfF
PhCHTf2
ð1Þ
25 °C
(40%)
1a
Published on the web August 4, 2005; DOI 10.1246/bcsj.78.1401

1402 Bull. Chem. Soc. Jpn., 78, No. 8 (2005)
BCSJ AWARD ARTICLE
PhCH2Br + CF3SO2Na
EtCN, reflux
2a
(94%)
N1
F4
1. t-BuLi (2.2 mol amt.)
F5
S2
Et2O, −78 °C, 0.5 h
PhCH2Tf
1a
2. Tf2O (1.1 mol amt.)
3a
−78 °C to rt, 1 h
3. 4 M HCl (1 M = 1 mol dm−3)
(79%)
S1
F3
F1
F
Scheme 1. Preparation of 1a.
F2
F
F
Tf
Tf
+
N
Table 1. Preparation of Arylbis(triflyl)methanes 1
F
N
Et
Me
CF3SO2Na (1.3 mol amt.)
F
ArCH2Tf
ArCH2X
EtCN, reflux
2
3
Fig. 1. The X-ray crystal structure of 5.
1. t-BuLi (1.1 mol amt.)
Et2O, −78 °C, 20 min
2. Tf2O (0.55 mol amt.)
−78 °C to rt, 1 h
ic ring is deactivated by electron-withdrawing groups,1b the re-
activity was strongly enhanced by refluxing in propiononitrile
instead of acetonitrile. The second step was accomplished by
the successive addition of t-BuLi (2.2 molar amounts) and trifl-
ic anhydride (1.1 molar amounts) to a solution of 3a.
ArCHTf2
3. repeat 1
4. repeat 2
1
Run
1
2
3, %a)
1, %b)
Various arylbis(triflyl)methanes 1 were prepared from aryl-
methyl halides 2 in high yield by applying this new methodol-
ogy (Table 1).13 Two portional additions of t-BuLi (1.1 molar
amount ꢃ 2) and of triflic anhydride (0.55 molar amount ꢃ 2)
were more effective to increase chemical yield of 1. Notably,
several novel compounds 1, which had been difficult to synthe-
size, could be easily prepared from deactivated 2; for example,
a sterically-hindered halide 2d and electron-deficient benzylic
halides 2e–g. Especially, 1g derived from 2g was a remarkably
strong acid (pKa ¼ 1:5 in CD3CO2D; superacid) and exhibited
extremely high catalytic activity for the acetylation of (ꢁ)-
menthol with acetic anhydride.14a In addition, a silicon Lewis
acid, which had a conjugate base of 1g as a ligand, was a
highly effective catalyst in comparison with Me3SiOTf and
Me3SiNTf2 for the condensation of trimethylhydroquinone
with isophytol to give (ꢄ)-ꢀ-tocopherol.14d
Br
3b, >99
1b, 84
2b
Br
2
3c, 99
1c, 98
2c
Cl
3
4
3d, 90
1d, 89
1e, 87
2d
2e
Br
F3C
3e, >99
The structure of the imidazolium salt of 1g (5) was con-
firmed by single-crystal X-ray analysis (Fig. 1).
Surprisingly, 4-tert-butyl-2,3,5,6-tetrafluorophenylbis(tri-
flyl)methane (6a) was obtained with 1g in the reaction of 3g
with triflic anhydride. The use of t-BuLi (1.1 mol amt.) and
triflic anhydride (0.55 mol amt.) completely suppressed the
formation of 6a and 1g was obtained in 95% yield based on
triflic anhydride. To explore the generality and scope of the
nucleophilic para-substitution of 1g, we examined the reaction
with several alkyllithium reagents (Table 2). Surprisingly,
even less-nucleophilic 3,4,5-trifluorophenyllithium and 3,5-
bis(trifluoromethyl)phenyllithium also reacted with 1g to give
6 in good yield. Compound 6 regiospecifically produced as a
single isomer without exceptions.14a
F3C
Br
5
6
3f, 76
1f, 75
CF3
2f
F
F
F
Br
1g, 45c)
(95)d)
3g, 89
F
F
2g
Furthermore, the nucleophilic para-substitution reaction of
1g could also be adapted to prepare 4-alkoxy-2,3,5,6-tetra-
fluorophenylbis(triflyl)methane 7 (Table 3). Several alcohols
were examined by reacting a lithium salt of 1g with the corre-
sponding sodium alkoxides in pyridine at room temperature.
a) Isolated yield from 2. b) Isolated yield from 3. c) Desired
compounds 1g and 6a were produced as a 1:1 mixture in
90% yield. d) Yield based on triflic anhydride, when t-BuLi
(1.1 mol amt.) and Tf2O (0.55 mol amt.) per 3g were added
with one portion, is indicated in parentheses.

A. Hasegawa et al.
Bull. Chem. Soc. Jpn., 78, No. 8 (2005) 1403
Table 2. Regiospecific Nucleophilic para-Substitution of 1g
F
F
F
F
F
F
Tf
H
Tf
Tf
H
RLi
R
1g
Tf
Et2O
F
F
6
9
RLi (mol amt.)
Conditions
ꢂ
6, %
F
F
F
F
t-BuLi (3)a)
n-BuLi (3)a)
BnLi (5)
ꢁ78 C, 1 h
6a, 87
6b, >95
6c, 83b)
6d, 83
6e, 75b)
6f, 70c)
Tf
H
Tf
ꢂ
ꢁ78 C, 1 h
CF3(CF2)12CH2O
ꢂ
ꢁ78 C, 6 h
PhLi (3)a)
ꢁ78 C to rt, 1 day
ꢂ
ꢂ
ꢂ
3,4,5-F3C6H2Li (5)
3,5-(CF3)2C6H3Li (5)
ꢁ20 C to rt, 3 h
10
ꢁ20 C to rt, 3 h
a) Ref. 8a. b) Starting material 1g was remained. c) Isolated
yield after sublimation.
Fig. 2. Polystyrene-bound and fluorous Brønsted acids.
Table 4. Regiospecific Nucleophilic para-Substitution of 1g
with Diols
Table 3. Regiospecific Nucleophilic para-Substitution of 1g
with Alcohols
1. C6F5CTf2Li
(4 mol amt.)
NaH (3 mol amt.)
ROH
rt to 70 °C, 1 day
NaH (2.1 mol amt.)
pyridine
0 °C to rt, 2 h
(3 equiv)
HO
OH
2. 4 M HCl
pyridine
0 °C to rt, 2 h
F
F
F
F
1. C6F5CTf2Li (1 mol amt.)
rt, 1 day
F
F
Tf
H
Tf
F
O
F
O
F
F
RO
2. 4 M HCl
Tf
H
Tf
H
7
Tf
F
F
Tf
11
ROH
7, %
Diol
11, %
C6H13OHa)
MeOCH2CH2OCH2CH2OH
PhOHb)
7a, 83
7b, 74
7c, >69
7d, 78
HO(CH2)3OH
HO(CH2)4OH
OH
11a, 85
11b, 86
CF3CH2OHb)
11c, 70
11d, 78
OH
OH
a) Ref. 8c. b) After addition of C6F5CTf2Li, the reaction mix-
ꢂ
ture was heated at 70 C.
OHa)
Pyridine was more effective as a solvent. In contrast, this reac-
tion did not occur smoothly in diethyl ether, which was effec-
tive in the para-substitution reactions with alkyllithiums. Since
sodium phenoxide was less reactive than aliphatic alkoxide,
the reaction required a slightly higher temperature. As a result,
compounds 7 were obtained in good yields. Surprisingly, even
when an electron-deficient alcohol such as CF3CH2OH was
used, the reaction proceeded smoothly to give 7d in good
yield.
Furthermore, it was also possible to introduce a hydroxy
group as well as alkyl and alkoxy groups. Compound 1g was
reacted with potassium hydroxide to give 4-hydroxy-2,3,5,6-
tetrafluorophenylbis(triflyl)methane (8) (Eq. 4).
a) The alcohol was prepared by hydrogenation of 3-cyclo-
hexene-1,1-dimethanol.
vent-swellable resin-bound super Brønsted acid, Polystyrene-
bound 2,3,5,6-tetrafluorophenylbis(triflyl)methane (9), and a
fluorous super Brønsted acid, 4-(1H,1H-perfluorotetradecyl-
oxy)-2,3,5,6-tetrafluorophenylbis(triflyl)methane(10)(Fig.2).14
In addition, various diols were examined as nucleophiles in-
stead of monoalcohols under similar conditions, and gave di-
basic acids 11 (Table 4). Dibasic acid is expected to have high-
er catalytic activity than monobasic acid due to the synergistic
effect of two acidic protons.
Diol-bound dibasic acids may be flexible bidentate acid cat-
alysts because diols show high flexibility. The intramolecular
interaction between two protons in a dibasic acid is expected
to be increased when its linker is changed from a flexible diol
to a rigid skeletal compound. Initially, 4,5-dibromo-2,7-di-tert-
butyl-9,9-dimethylxanthene (12), which is commercially avail-
able, was used as a precursor for a nucleophile. The lithium
salt of 1g was added to 12 lithiated with t-BuLi, and the reac-
F
F
KOH (5 mol amt.)
Tf
H
Tf
1g
HO
ð4Þ
t-BuOH
reflux, 3 h
(66%)
F
F
8
We previously reported that the nucleophilic para-substitu-
tion reaction of 1g could be adapted to prepare an organic-sol-
ꢂ
tion mixture was heated at 50 C to give the desired dibasic

1404 Bull. Chem. Soc. Jpn., 78, No. 8 (2005)
BCSJ AWARD ARTICLE
acid 13a in 28% yield (Eq. 5). The pKa value of 13a in
1
dibenzofuran (14)15 and 1,8-dibromobiphenylene (16).16 Lith-
iation of 14 was followed by reaction of the lithium salt of 1g
under similar conditions to afford 13b in 29% yield (Eq. 6).
CD3CO2D was measured by the H NMR method of Schantl
and co-workers.10 Compound 13a was a superacid like 1g, al-
though the para-substitution of 1g by a phenyl group lowered
its Brønsted acidity.
1. t-BuLi (4.4 mol amt.), THF
−78 °C
2. C6F5CTf2Li (2.5 mol amt.)
O
t-Bu
t-Bu
Br
Br
−78 °C to 45 °C, 19 h
(29%)
O
14
Br
Br
ð6Þ
12
O
F
F
1. t-BuLi
(4.4 mol amt.)
THF, −78 °C, 1 h
2. C6F5CTf2Li
(2.5 mol amt.)
−78 °C to 50 °C
42 h
F F
(28%)
F
F
F
F
Tf
Tf
Tf
Tf
ð5Þ
H
H
t-Bu
t-Bu
13b
The structure of the bipyridinium salt of 13b (15) was con-
firmed by single-crystal X-ray analysis (Fig. 3).
Lithiation of 1617 was followed by the reaction of lithium
salt of 1g under similar conditions to afford 13c in 12% yield
(Eq. 7).
O
F4
F4
Tf
Tf
H
H
Tf
Tf
1. t-BuLi (4.4 mol amt.), THF
−78 °C to −20 °C
13a (pKa = 6.3)
2. C6F5CTf2Li (2.5 mol amt.)
The distance between the two acidic protons of a dibasic
acid may affect its Brønsted acidity and catalytic activity.
Therefore, we decided to synthesize new linkers, 1,8-dibromo-
Br
Br
−20 °C to 50 °C
(12%)
16
ð7Þ
F4
F4
Tf
Tf
H H
Tf
Tf
13c
1,1-Bis(triflyl)alkanes could also be prepared (Scheme 2).
Trifluoromethyl sulfones can be prepared by the nucleophilic
substitution of alkyl halides with sodium trifluoromethanesul-
CF3SOCl (1.5 mol amt.)
pyridine (1.5 mol amt.)
n-C8H17OH
0 °C to rt, 1 d
(83%)
O
F
F
n-C8H17Tf
n-C8H17OSOCF3
HMPA
145 °C, 12 h
(75%)
F F
18
17
F
F
F
F
1. Tf2O (0.55 mol amt.) Et2O
2. t-BuLi (1.1 mol amt.)
−78 °C to rt, 3 h
Tf
Tf
Tf
Tf
n-C7H15CHTf2
19
N
3. repeat 1
4. repeat 2
(68%)
N
Fig. 3. The X-ray crystal structure of 15.
Scheme 2. Preparation of 1,1-bis(triflyl)octane (19).

A. Hasegawa et al.
Bull. Chem. Soc. Jpn., 78, No. 8 (2005) 1405
Calcd for C12H9F3O2S: C, 52.55; H, 3.31%. Found: C, 52.52;
H, 3.18%.
1-Naphthylmethyl Trifluoromethyl Sulfone (3c): IR (KBr)
finate. However, this reaction proceeds very slowly with pri-
mary halides due to the low nucleophilicity of the rather stable
anion. An alternative synthesis of trifluoromethyl sulfones
from alcohols was examined by following the literature.17
The reaction of the alcohol and CF3SOCl in the presence of
pyridine provided the triflinate 17. The triflinate cleanly rear-
ranged to the corresponding trifluoromethyl sulfone 18 on
heating at 145 C in HMPA, and subsequent reaction of the
lithium salt of 18 with triflic anhydride as in the preparation
of arylbis(triflyl)methanes gave 1,1-bis(triflyl)octane (19).
1510, 1358, 1223, 1200, 804, 776, 658, 486 cmꢁ1 1H NMR
.
(300 MHz, CDCl3) ꢁ 4.99 (s, 2H), 7.53 (dd, J ¼ 7:8, 8.4 Hz,
1H), 7.62 (d, J ¼ 7:8 Hz, 1H), 7.58 (ddd, J ¼ 0:9, 6.9, 8.3 Hz,
1H), 7.65 (ddd, J ¼ 1:5, 6.9, 8.4 Hz, 1H), 7.93 (dd, J ¼ 1:5, 8.3
Hz, 1H), 7.98 (dd, J ¼ 8:4 Hz, 1H), 8.04 (dd, J ¼ 0:9, 8.4 Hz,
ꢂ
1H). 13C NMR (125 MHz, CDCl3) ꢁ 53.0, 119.2, 120.0 (q, JCF
¼
326 Hz, 1C, CF3), 123.3, 125.3, 126.5, 127.5, 129.0, 131.1, 131.5,
132.3, 134.0. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ78:1 (s, 3F, CF3).
Anal. Calcd for C12H9F3O2S: C, 52.55; H, 3.31%. Found: C,
52.28; H, 3.31%.
Conclusion
We have discovered a practical method for synthesizing
arylbis(triflyl)methanes 1 starting from commercially available
benzylic halides and 1,1-bis(triflyl)alkanes starting from com-
mercially available 1-alkanols. Furthermore, we also found
that the nucleophilic para-substitution reaction for 1g occurred
with some kinds of nucleophiles. The present methods made it
possible to design new Brønsted acids such as 6, 7, 11, and 13.
Their Brønsted acidity and catalytic activity depended on
the substituent at C-4 of 1g. In addition, conjugate bases of
these acids are expected to be effective ligands for Lewis acid
catalysts.
2,4,6-Trimethylphenyl Trifluoromethyl Sulfone (3d): IR
1
(KBr) 1358, 1206, 1117, 864, 619, 550, 500, 469 cmꢁ1. H NMR
(300 MHz, CDCl3) ꢁ 2.29 (s, 3H), 2.43 (s, 6H), 4.62 (s, 2H), 6.96
(s, 2H). 13C NMR (125 MHz, CDCl3) ꢁ 20.3, 21.0 (2C), 49.8,
117.0, 120.0 (q, JCF ¼ 326 Hz, 1C, CF3), 129.9 (2C), 139.7
(2C), 139.8. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ79:7 (s, 3F, CF3).
4-Trifluromethylphenylmethyl Trifloromethyl Sulfone
(3e):1b IR (KBr) 1356, 1341, 1227, 1210, 1144, 1121, 855,
658, 513 cmꢁ1 1H NMR (300 MHz, CDCl3) ꢁ 4.53 (s, 2H),
.
7.58 (d, J ¼ 8:0 Hz, 2H), 7.72 (d, J ¼ 8:0 Hz, 2H). 13C NMR
(75 MHz, CDCl3) ꢁ 55.5, 119.7 (q, JCF ¼ 327 Hz, 1C, CF3),
123.7 (q, JCF ¼ 271 Hz, 1C, CF3), 126.3 (q, JCF ¼ 3:8 Hz, 2C),
127.3 (s, 1C), 131.8 (s, 2C), 132.3 (q, JCF ¼ 33 Hz, 1C). 13C NMR
(125 MHz, CDCl3) ꢁ 55.5, 119.6 (q, JCF ¼ 326 Hz, 1C, CF3),
123.6 (q, JCF ¼ 271 Hz, 1C, CF3), 126.2 (q, JCF ¼ 41 Hz, 2C),
127.3, 131.7 (2C), 132.2 (q, JCF ¼ 33 Hz, 1C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ77:5 (s, 3F, CF3), ꢁ64:3 (s, 3F, CF3). HRMS
(EI) calcd for C9H6F6O2S: [M]þ 291.9993. Found: 292.0012.
3,5-Bis(trifluoromethyl)phenylmethyl Trifluoromethyl Sul-
fone (3f): IR (KBr) 1376, 1362, 1277, 1175, 1117, 918, 910,
Experimental
General. Infrared (IR) spectra were recorded on a JASCO
FT/IR 460 plus spectrometer. 1H, 13C, and 19F NMR spectra were
recorded on a Varian Gemini-300 instrument. Unless otherwise
noted, 1H, 13C, and 19F NMR spectra are referenced against inter-
nal tetramethylsilane (ꢁ ¼ 0), CDCl3 (ꢁ ¼ 77:0), and CF3C6H5
(ꢁ ¼ ꢁ64:0), respectively. High-resolution mass (HRMS) analy-
ses were carried out by Daikin Industries, Ltd., or at the Chemical
Instrument Center, Nagoya University. Microanalyses were per-
formed at the Chemical Instrument Center, Nagoya University.
Unless otherwise indicated, all compounds were purchased. Com-
mercial reagents were used as received with the following excep-
tions: pyridine and HMPA were distilled from calcium hydride
(CaH2). Et2O and THF were distilled from sodium diphenylketyl.
Flash chromatography was performed using silica gel 60 (230–
400 mesh), purchased from Merck. All reactions were carried
out under an atmosphere of nitrogen.
669 cmꢁ1 1H NMR (300 MHz, CDCl3) ꢁ 4.60 (s, 2H), 7.91 (s,
.
2H), 8.01 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ 55.0, 119.6
(q, JCF ¼ 326 Hz, 1C, CF3), 122.6 (q, JCF ¼ 272 Hz, 2C,
2CF3), 124.2 (septet, JCF ¼ 4 Hz, 1C), 126.1, 131.3 (2C), 132.9
(q, JCF ¼ 34 Hz, 2C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ77:4 (s,
3F, CF3), ꢁ64:3 (s, 6F, 2CF3). HRMS (EI) calcd for C10H5F9O2S:
[M]þ 359.9867. Found: 359.9863.
Pentafluorophenylmethyl Trifluoromethyl Sulfone (3g): IR
(KBr) 1509, 1374, 1210, 1121, 995 cmꢁ1 1H NMR (300 MHz,
.
General Procedure for the Preparation of Benzylic Trifluo-
romethyl Sulfone (3) (Table 1). A solution of a benzylic halide
2 (10 mmol) and CF3SO2Na (2.0 g, 13 mmol) in propiononitrile
(30 mL) was heated at reflux temperature. While disappearance
of the starting halide was monitored by TLC, the mixture was
cooled, the salts were removed by filtration and the filtrate was
concentrated under reduced pressure. The residue was purified
by column chromatography using a linear AcOEt gradient in
hexane to give 3 as a solid.
CDCl3) ꢁ 4.64 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ 44.3,
100.0 (dt, JCF ¼ 4, 17 Hz, 1C, ipso-C), 119.5 (q, JCF ¼ 326 Hz,
1C, CF3), 137.9 (d, JCF ¼ 251 Hz, 2C, 2m-C), 142.8 (d, JCF
¼
258 Hz, 1C, p-C), 145.9 (d, JCF ¼ 258 Hz, 2C, 2o-C). 19F NMR
(282 MHz, CDCl3) ꢁ ꢁ160:0 (d, J ¼ 15:2 Hz, 2F, 2m-F),
ꢁ149:0 (s, 1F, p-F), ꢁ139:4 (d, J ¼ 15:2 Hz, 2F, 2o-F), ꢁ78:3
(s, 3F, CF3).
General Procedure for the Preparation of Arylbis(triflyl)-
methanes 1a–f (Fig. 1). To a solution of 3 (0.5 mmol) in dry
Et2O (3 mL) was added t-BuLi (0.34 mL, 0.55 mmol, 1.6 M solu-
tion in hexane) dropwise at ꢁ78 ꢂC, and the resulting mixture was
stirred for 20 min. Triflic anhydride (92 mL, 0.28 mmol) was then
added, and the resulting mixture was allowed to warm to room
temperature over a period of 1 h. After the reaction mixture was
cooled to ꢁ78 ꢂC, t-BuLi (0.34 mL, 0.55 mmol, 1.6 M in hexane)
was added dropwise, and the resulting mixture was stirred for 20
min. Triflic anhydride (0.28 mmol) was then added, and the result-
ing mixture was allowed to reach room temperature over a period
of 1 h before the reaction was quenched with water. The resultant
mixture was neutralized and washed with hexane. The aqueous
2-Benzyl Trifluoromethyl Sulfone (3a):1c IR (KBr) 1362,
1347, 1223, 1198, 1188, 1125, 776, 698, 640, 525, 507 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 4.48 (s, 2H), 7.42–7.47 (m, 5H).
19F NMR (282 MHz, CDCl3) ꢁ ꢁ77:6 (s, 3F, CF3).
2-Naphthylmethyl Trifluoromethyl Sulfone (3b): IR (KBr)
1358, 1345, 1221, 1194, 1125, 831, 756, 658, 608, 486 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 4.65 (s, 2H), 7.50 (dd, J ¼ 1:8,
8.4 Hz, 1H), 7.54–7.58 (m, 2H), 7.86–7.94 (m, 4H). 13C NMR
(125 MHz, CDCl3) ꢁ 56.3, 119.8 (q, JCF ¼ 326 Hz, 1C, CF3),
120.3, 126.9, 127.4, 127.5, 127.8, 128.1, 129.2, 131.5, 133.1,
133.6. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ77:6 (s, 3F, CF3). Anal.

1406 Bull. Chem. Soc. Jpn., 78, No. 8 (2005)
BCSJ AWARD ARTICLE
pressure. The residue was subjected to bulb-to-bulb distillation
phase was acidified with 4 M aqueous HCl and extracted with
ether twice. The organic layers were dried over magnesium sul-
fate, filtered and concentrated under reduced pressure. The residue
was subjected to bulb-to-bulb distillation to give 1 as a solid.
ꢂ
ꢂ
(85 C, 0.05 Torr) to give 1g as a solid. mp 86–87 C. IR (KBr)
1522, 1501, 1347, 1321, 1198, 1127, 1024, 988, 613 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 6.21 (brs, 1H). 13C NMR (125
MHz, CDCl3) ꢁ 70.4, 98.0 (s, 1C, ipso-C), 119.2 (q, JCF ¼ 330
Phenylbis(triflyl)methane (1a):11
1242, 1219, 1184, 1102, 806, 695, 660, 608, 585, 507 cmꢁ1
IR (KBr) 2950, 1381,
.
Hz, 2C, 2CF3), 137.8 (d, JCF ¼ 258 Hz, 1C, m-C), 138.6 (d, JCF ¼
1H NMR (300 MHz, CDCl3) ꢁ 5.97 (s, 1H), 7.54–7.68 (m, 5H).
13C NMR (125 MHz, CDCl3) ꢁ 80.7, 119.3 (q, JCF ¼ 329 Hz,
2C, 2CF3), 130.0 (2C), 131.8 (br), 132.9 (2C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ73:8 (s, 6F, 2CF3).
257 Hz, 1C, m-C), 144.7 (d, JCF ¼ 264 Hz, 1C, p-C), 145.4 (d,
JCF ¼ 262 Hz, 1C, o-C), 147.2 (d, JCF ¼ 262 Hz, 1C, o-C).
19F NMR (282 MHz, CDCl3) ꢁ ꢁ157:9 (dt, J ¼ 6:2, 21.5 Hz,
1F, m-F), ꢁ156:8 (dt, J ¼ 6:2, 21.5 Hz, 1F, m-F), ꢁ142:6 (tt,
J ¼ 5:9, 21.5 Hz, 1F, p-F), ꢁ140:3 (br, 1F, o-F), ꢁ127:7 (ddd,
J ¼ 5:9, 15.2, 21.5 Hz, 1F, o-F), ꢁ75:2 (s, 6F, 2CF3). HRMS
(EI) calcd for C9HO4F11S2: [M]þ 445.9141. Found: 445.9137.
Procedure for the Preparation of 1-Ethyl-3-methylimidazol-
ium Pentafluorophenylbis(triflyl)methanide (5). A solution of
1-ethyl-3-methylimidazolium bromide (955 mg, 5.0 mmol) and
lithium pentafluorophenylbis(triflyl)methanide (2.26 g, 5.0 mmol)
in H2O (8 mL) were stirred at 70 ꢂC for 1 d. The resulting mixture
was extracted with AcOEt. The organic layer was dried over so-
dium sulfate, filtered and concentrated under reduced pressure.
The crude product was purified by column chromatography on
neutral aluminum oxide (eluent: AcOEt) to give 5. Finally, the
product was dried under reduced pressure (80 ꢂC, 0.67 hPa, over-
2-Naphthylbis(triflyl)methane (1b): IR (KBr) 1393, 1381,
1244, 1213, 1103, 646, 586 cmꢁ1 1H NMR (300 MHz, CDCl3)
.
ꢁ 6.10 (s, 1H), 7.61–7.71 (m, 3H), 7.92–7.99 (m, 2H), 8.03 (d, J ¼
8:4 Hz, 2H). 13C NMR (125 MHz, CDCl3) ꢁ 80.9, 116.3, 119.3 (q,
JCF ¼ 329 Hz, 2C, 2CF3), 127.7, 128.0, 129.1, 130.1, 132.8,
133.4, 134.7. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ73:6 (s, 6F,
2CF3). HRMS (EI) calcd for C13H8O4F6S2: [M]þ 405.9768.
Found: 405.9761.
1-Naphthylbis(triflyl)methane (1c): IR (KBr) 1389, 1383,
1
1215, 1111, 770, 650, 504 cmꢁ1. H NMR (300 MHz, CDCl3) ꢁ
6.87 (s, 1H), 7.62–7.80 (m, 4H), 8.02 (d, J ¼ 8:4 Hz, 1H), 8.16
(d, J ¼ 8:4 Hz, 1H), 8.37 (d, J ¼ 7:5 Hz, 1H). 13C NMR (125
MHz, CDCl3) ꢁ 74.6, 114.1, 119.4 (q, JCF ¼ 328 Hz, 2C,
2CF3), 119.9, 125.4, 127.0, 128.9, 130.1, 131.5, 131.7, 133.8,
134.0. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ74:2 (s, 6F, 2CF3). HRMS
(EI) calcd for C13H8O4F6S2: [M]þ 405.9768. Found: 405.9761.
ꢂ
night). mp 52 C. IR (KBr) 1517, 1493, 1347, 1328, 1177, 1129,
1
1020, 608 cmꢁ1. H NMR (300 MHz, DMSO-d6) ꢁ 1.40 (t, J ¼
7:2 Hz, 3H), 3.84 (s, 3H), 4.18 (q, J ¼ 7:2 Hz, 2H), 7.69 (s,
1H), 7.78 (s, 1H), 9.10 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ
15.1, 35.7, 44.2, 55.0, 107.6, 120.8 (q, JCF ¼ 330 Hz, 2C,
2CF3), 122.0, 123.7, 136.3, 136.6 (d, JCF ¼ 230 Hz, 2C), 147.5
(d, JCF ¼ 247 Hz, 3C). 19F NMR (282 MHz, CD3CN) ꢁ ꢁ166:0
(m, 2F), ꢁ155:3 (m, 1F), ꢁ136:4 (m, 2F), ꢁ81:2 (s, 6F, 2CF3).
Anal. Calcd for C15H11F11N2O4S2: C, 32.32; H, 2.17; N, 5.03%.
Found: C, 32.57; H, 2.08; N, 5.12%.
2,4,6-Trimethylphenylbis(triflyl)methane (1d):
.
IR (KBr)
1397, 1383, 1217, 1119, 1107, 642, 590 cmꢁ1 1H NMR (300
MHz, CDCl3) ꢁ 2.33 (s, 3H), 2.35 (s, 3H), 2.61 (s, 3H), 6.48 (s,
1H), 7.00 (s, 1H), 7.08 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ
20.2, 21.1, 22.2, 77.7, 115.9, 119.4 (q, JCF ¼ 328 Hz, 2C,
2CF3), 130.4, 132.2, 140.0, 142.2, 142.6. 19F NMR (282 MHz,
CDCl3) ꢁ ꢁ76:3 (s, 6F, 2CF3). HRMS (EI) calcd for
C13H12O4F6S2: [M]þ 398.0081. Found: 398.0089.
X-ray Crystallographic Analysis of 5:
Crystal data:
4-Trifluoromethylphenylbis(triflyl)methane (1e): IR (KBr)
C15H11F11N2O4S2, Mw ¼ 556:38, crystal dimensions 0:20 ꢃ
1393, 1383, 1327, 1231, 1171, 1136, 1111, 860, 671, 610 cmꢁ1
.
0:20 ꢃ 0:15 mm3, monoclinic, space group P21=n (#14), a ¼
1H NMR (300 MHz, CDCl3) ꢁ 5.98 (s, 3H), 7.84 (s, 4H).
13C NMR (125 MHz, CDCl3) ꢁ 80.4, 120.0 (q, JCF ¼ 329 Hz,
2C, 2CF3), 123.8 (q, JCF ¼ 271 Hz, 1C, CF3), 124.2, 127.6 (q, J ¼
4 Hz, 2C), 130.0 (2C), 135.6 (q, JCF ¼ 33 Hz, 1C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ73:5 (s, 6F, 2CF3), ꢁ64:7 (s, 3F, CF3). HRMS
(EI) calcd for C10H5O4F9S2: [M]þ 423.9486. Found: 423.9471.
3,5-Bis(trifluoromethyl)phenylbis(triflyl)methane (1f): IR
(KBr) 1395, 1374, 1285, 1223, 1194, 1179, 1144, 1105, 936,
10:4467ð19Þ, b ¼ 14:491ð3Þ, c ¼ 14:507ð3Þ A, V ¼ 2139:5ð7Þ
ꢀ
3
ꢀ 3
A , Z ¼ 4, Dc ¼ 1:727 g/cm , ꢂ ¼ 0:370 mmꢁ1, T ¼ 223 K.
X-ray crystallographic analysis was performed with a Bruker
SMART APEX diffractometer (graphite monochromator, Mo Kꢀ
ꢀ
radiation, ꢃ ¼ 0:71073 A). The structure was solved by direct
methods and expanded using Fourier techniques. 5674 reflections
were independent and unique, and 4535 with I > 2ꢄðIÞ (2ꢅmax
¼
29:12ꢂ) were used for the solution of the structure. The non-
hydrogen atoms were refined anisotropically. R ¼ 0:0461 and
Rw ¼ 0:1376.
909, 629, 519 cmꢁ1 1H NMR (300 MHz, CDCl3) ꢁ 6.05 (s,
.
1H), 8.13 (s, 2H), 8.18 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ
78.9, 119.2 (q, JCF ¼ 329 Hz, 2C, 2CF3), 122.2 (q, JCF ¼ 329
Hz, 2C, 2CF3), 122.9, 126.7 (septet, JCF ¼ 4 Hz, 1C), 131.6 (s,
2C), 133.8 (q, JCF ¼ 35 Hz, 2C). 19F NMR (282 MHz, CDCl3)
ꢁ ꢁ73:2 (s, 6F, 2CF3), ꢁ64:3 (s, 3F, CF3). HRMS (EI) calcd
for C11H4O4F12S2: [M]þ 472.9375. Found: 472.9372.
General Procedure for the Preparation of 4-Alkyl- or 4-
Aryl-2,3,5,6-tetrafluorophenylbis(triflyl)methane (6). To a so-
lution of 1g (0.22 g, 0.5 mmol) in Et2O (3 mL) was added a solu-
tion of alkyl- or aryllithium [t-BuLi (1.5 mmol), n-BuLi (1.5
mmol), BnLi (2.5 mmol),18 PhLi (1.5 mmol), and 3,4,5-F3C6H2Li
(2.5 mmol)19] at ꢁ78 ꢂC, and the resulting mixture was stirred
under the following conditions: t-BuLi (ꢁ78 ꢂC, 1 h), n-BuLi
(ꢁ78 ꢂC, 1 h), BnLi (ꢁ78 ꢂC, 6 h), PhLi (ꢁ78 ꢂC to rt, 1 d),
Procedure for the Preparation of Pentafluorophenylbis(tri-
flyl)methane (1g): To a solution of 3g (0.5 mmol) in dry Et2O (3
mL) was added t-BuLi (0.34 mL, 0.55 mmol, 1.6 M solution in
hexane) dropwise at ꢁ78 ꢂC, and the resulting mixture was stirred
for 20 min. Triflic anhydride (92 mL, 0.28 mmol) was then added,
and the resulting mixture was allowed to warm to room tempera-
ture over a period of 1 h before the reaction was quenched with
water. The resultant mixture was neutralized and washed with
hexane. The aqueous phase was acidified with 4 M aqueous
HCl and extracted with ether twice. The organic layers were dried
over magnesium sulfate, filtered and concentrated under reduced
ꢂ
and 3,4,5-F3C6H2Li (ꢁ20 C to rt, 3 h) before the reaction was
quenched with water. The resultant mixture was neutralized with
1 M aqueous HCl and washed with hexane. The aqueous phase
was acidified with 4 M aqueous HCl and extracted with Et2O
twice. The organic layers were dried over magnesium sulfate,
filtered and concentrated under reduced pressure to give 6 as a
light brown solid.
4-tert-Butyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane (6a):

A. Hasegawa et al.
Bull. Chem. Soc. Jpn., 78, No. 8 (2005) 1407
IR (CHCl3) 3021, 1480, 1456, 1117, 967, 669 cmꢁ1
.
1H NMR
resulting mixture was allowed to warm to room temperature over
a period of 3 h before the reaction was quenched with water. The
resultant mixture was neutralized with 1 M aqueous HCl and
washed with hexane. The aqueous phase was acidified with 4 M
aqueous HCl and extracted with ether twice. The organic layers
were dried over magnesium sulfate, filtered and concentrated un-
der reduced pressure to give a brown solid that was subjected to
vacuum sublimation (150 ꢂC, 6.7 Pa) to give 6f as a colorless sol-
(300 MHz, CDCl3) ꢁ 1.54 (s, 9H), 6.24 (s, 1H). 13C NMR (125
MHz, CDCl3) ꢁ 30.4 (3C), 37.9, 70.8, 99.3 (t, JCF ¼ 16 Hz,
1C), 119.2 (q, JCF ¼ 328 Hz, 2C, 2CF3), 134.2 (t, JCF ¼ 13 Hz,
1C), 145.2 (d, JCF ¼ 251 Hz, 1C, m-C), 145.6 (d, JCF ¼ 250
Hz, 1C, o-C), 146.4 (d, JCF ¼ 251 Hz, 1C, o-C), 147.0 (d, JCF
¼
258 Hz, 1C, m-C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ142:8 (m,
1F), ꢁ135:1 (dd, J ¼ 10:6, 18.3 Hz, 1F, m-F), ꢁ133:9 (dd,
J ¼ 10:6, 18.3 Hz, 1F, m-F), ꢁ130:3 (m, J ¼ 9:0, 21.4 Hz, 1F,
o-F), ꢁ75:4 (s, 6F, 2CF3). HRMS (EI) calcd for C13H10O4F10S2:
[M]þ 483.9861. Found: 483.9852.
id. IR (KBr) 1489, 1375, 1285, 1210, 1173, 1136, 1119 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 6.31 (s, 1H), 8.01 (s, 2H), 8.07
(s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ 70.6, 103.0 (t, JCF ¼ 15
4-Butyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane (6b):
IR (CHCl3) 3021, 1497, 1483, 1410, 1117, 669 cmꢁ1
Hz, 1C), 119.3 (q, JCF ¼ 328 Hz, 2C, 2CF3), 122.7 (q, JCF ¼
.
1H NMR
272 Hz, 2C, 2CF3), 123.3 (t, JCF ¼ 15 Hz, 1C), 124.2–124.4
(m, 1C), 127.8, 130.3 (2C), 132.8 (q, JCF ¼ 34 Hz, 2C), 143.7
(d, JCF ¼ 254 Hz, 1C), 144.5 (d, JCF ¼ 253 Hz, 1C), 145.1 (d,
JCF ¼ 255 Hz, 1C), 146.8 (d, JCF ¼ 261 Hz, 1C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ140:3–ꢁ140:2 (m, 2F), ꢁ139:1 (dd, J ¼ 9:3,
22.8 Hz, 1F), ꢁ127:9–ꢁ127:6 (m, 1F), ꢁ75:2 (s, 6F), ꢁ64:2 (s,
6F). HRMS (EI) calcd for C17H14O4F16S2: [M]þ 639.9296.
Found: 639.9307.
(300 MHz, CDCl3) ꢁ 0.97 (t, J ¼ 7:6 Hz, 3H), 1.40 (septet, J ¼
7:6 Hz, 2H), 1.64 (quintet, J ¼ 7:6 Hz, 2H), 2.83 (t, J ¼ 7:6
Hz, 2H), 6.25 (s, 1H). 13C NMR (125 MHz, CDCl3) ꢁ 13.6,
22.4, 23.3, 30.9, 70.9, 99.2 (t, J ¼ 16 Hz, 1C), 128.2 (t, J ¼ 18
Hz, 1C), 144.4 (d, JCF ¼ 251 Hz, 1C), 144.8 (d, JCF ¼ 250 Hz,
1C), 145.6 (d, JCF ¼ 250 Hz, 1C), 146.3 (d, JCF ¼ 258 Hz, 1C).
19F NMR (282 MHz, CDCl3) ꢁ ꢁ142:8 (br, 1F, o-F), ꢁ141:6
(dd, J ¼ 12:3, 21.4 Hz, 1F, m-F), ꢁ140:4 (dd, J ¼ 12:3, 21.4
Hz, 1F, m-F), ꢁ130:6–ꢁ130:4 (m, 1F, o-F), ꢁ75:4 (s, 6F,
2CF3). HRMS (EI) calcd for C13H10O4F10S2: [M]þ 483.9861.
Found: 483.9873.
General Procedure for the Preparation of 4-Alkoxy-2,3,5,6-
tetrafluorophenylbis(triflyl)methane (7). To a solution of NaH
(0.48 g, 12 mmol, 60% oil suspension) in pyridine (15 mL) was
ꢂ
added alcohol (12 mmol) at 0 C. The resulting mixture was al-
4-Benzyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane (6c):
IR (CHCl3) 3021, 1497, 1410, 1347, 1117, 1022, 992, 669
lowed to reach room temperature over a period of 1 h. After cool-
ing to 0 ꢂC, lithium pentafluorophenylbis(triflyl)methanide (1.8 g,
4 mmol) was added to the mixture. The resulting mixture was al-
lowed to reach room temperature and stirred at the same temper-
ature (PhOH, 70 ꢂC) for 1 d before the reaction was quenched with
water at 0 ꢂC. The resultant mixture was neutralized with 1 M
aqueous HCl and washed with hexane. The aqueous phase was
acidified with 4 M aqueous HCl and extracted with ether twice.
The organic layers were dried over magnesium sulfate, filtered
and concentrated under reduced pressure. Furthermore, excess al-
cohol in the residue was removed by vacuum sublimation to give
7. If the product was solid, it was recrystallized from CHCl3–
toluene.
1
cmꢁ1. H NMR (300 MHz, CDCl3) ꢁ 4.15 (s, 2H), 6.24 (s, 1H),
7.24–7.34 (m, 5H). 13C NMR (125 MHz, CDCl3) ꢁ 29.3, 70.8,
100.1 (t, JCF ¼ 16 Hz, 1C), 119.2 (q, JCF ¼ 328 Hz, 2C, 2CF3),
126.5 (t, JCF ¼ 18 Hz, 1C), 127.5, 128.5 (s, 2C), 135.9, 144.6
(d, JCF ¼ 251 Hz, 1C), 144.7 (d, JCF ¼ 249 Hz, 1C), 145.5 (d,
JCF ¼ 249 Hz, 1C), 146.3 (d, JCF ¼ 259 Hz, 1C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ142:0 (br, 1F, o-F), ꢁ140:4 (dd, J ¼ 13:0,
22.0 Hz, 1F, m-F), ꢁ139:3 (dd, J ¼ 13:0, 22.0 Hz, 1F, m-F),
ꢁ129:7–ꢁ129:6 (m, 1F, o-F), ꢁ75:3 (s, 6F, 2CF3). HRMS (EI)
calcd for C16H8O4F10S2: [M]þ 517.9704. Found: 517.9694.
4-Phenyl-2,3,5,6-tetrafluorophenylbis(triflyl)methane (6d):
IR (KBr) 1487, 1441, 1410, 1395, 1225, 1186, 1117, 1107, 974
4-Hexyloxy-2,3,5,6-tetrafluorophenylbis(triflyl)methane (7a):
See Ref. 14c.
4-[2-(2-Methoxyethoxy)ethoxy]-2,3,5,6-tetrafluorophenyl-
bis(triflyl)methane (7b): IR (neat) 3501, 2944, 1501, 1348,
1195, 1119, 1063, 1020, 982, 759, 611 cmꢁ1 1H NMR (300
.
cmꢁ1
(m, 5H). 13C NMR (125 MHz, CDCl3) ꢁ 70.9, 100.6 (q, JCF
16 Hz, 1C), 119.3 (q, JCF ¼ 328 Hz, 2C, 2CF3), 125.7, 126.8 (t,
.
1H NMR (300 MHz, CDCl3) ꢁ 6.32 (s, 1H), 7.46–7.60
¼
J ¼ 16 Hz, 1C), 128.9 (2C), 130.0 (2C), 130.3, 139.3 (d, JCF
¼
255 Hz, 1C), 144.5 (d, JCF ¼ 245 Hz, 1C), 145.0 (d, JCF ¼ 252
Hz, 1C), 146.7 (d, JCF ¼ 256 Hz, 1C). 19F NMR (282 MHz,
CDCl3) ꢁ ꢁ145:0 (m, 1F, o-F), ꢁ140:7 (dd, J ¼ 12:1, 21.4 Hz,
1F, m-F), ꢁ139:5 (dd, J ¼ 12:1, 21.4 Hz, 1F, m-F), ꢁ129:6–
ꢁ129:4 (m, 1F, o-F), ꢁ75:3 (s, 6F, 2CF3). HRMS (EI) calcd for
C15H6O4F10S2: [M]þ 503.9548. Found: 503.9560.
MHz, CDCl3) ꢁ 3.29 (s, 3H), 3.43 (t, J ¼ 4:5 Hz, 2H), 3.59 (t, J ¼
4:5 Hz, 2H), 3.80 (t, J ¼ 4:2 Hz, 2H), 4.52 (brs, 2H), 6.13 (s, 1H).
13C NMR (125 MHz, CDCl3) ꢁ 58.9, 70.2, 70.8, 70.9, 71.8, 74.4,
94.2 (t, JCF ¼ 15 Hz, 1C), 119.2 (q, JCF ¼ 328 Hz, 2C, 2CF3),
140.6 (d, JCF ¼ 248 Hz, 1C), 141.3 (d, JCF ¼ 250 Hz, 1C),
142.6–142.8 (m, 1C), 145.5 (d, JCF ¼ 248 Hz, 1C), 147.0 (d,
JCF ¼ 257 Hz, 1C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ154:1 (dd,
J ¼ 6:0, 21.3 Hz, 1F), ꢁ153:2 (dd, J ¼ 6:0, 21.3 Hz, 1F),
ꢁ142:6–ꢁ124:7 (m, 1F), ꢁ130:5 (dt, J ¼ 9:0, 21.3 Hz, 1F),
ꢁ75:0 (s, 6F, 2CF3). HRMS (FAB) calcd for C14H12F10O7S2:
½M þ Hꢅþ 546.9943. Found: 546.9941.
4-(3,4,5-Trifluoromethyl)-2,3,5,6-tetrafluorophenylbis(tri-
flyl)methane (6e): 1H NMR (300 MHz, CDCl3) ꢁ 6.30 (s, 1H),
7.20–7.24 (m, 2H). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ156:4 (dt,
J ¼ 6:1, 21.4 Hz, 1F), ꢁ140:8–ꢁ140:7 (m, 2F), ꢁ140:3 (dd, J ¼
12:3, 24.4 Hz, 1F), ꢁ139:0 (dd, J ¼ 12:3, 24.4 Hz, 1F), ꢁ132:9–
ꢁ132:8 (m, 2F), ꢁ128:2–ꢁ128:1 (m, 1F), ꢁ75:2 (s, 6F, 2CF3).
4-[3,5-Bis(trifluoromethyl)phenyl]-2,3,5,6-tetrafluorophen-
ylbis(triflyl)methane (6f). To a solution of 3,5-bis(trifluoro-
methyl)bromobenzene (96 mL, 0.55 mmol) in Et2O (1 mL) was
added BuLi (0.32 mL, 0.51 mmol, 1.6 M solution in hexane) as
4-Phenoxy-2,3,5,6-tetrafluorophenylbis(triflyl)methane (7c):
IR (KBr) 3046, 2942, 1650, 1592, 1499, 1347, 1214, 1200, 1118,
1
1023, 1001, 978, 754, 641, 614, 579 cmꢁ1. H NMR (300 MHz,
CDCl3) ꢁ 6.25 (s, 1H), 7.03 (d, J ¼ 8:1 Hz, 2H), 7.21 (t, J ¼
7:5 Hz, 1H), 7.40 (t, J ¼ 8:0 Hz, 2H). 13C NMR (125 MHz,
CDCl3) ꢁ 70.8, 97.4 (t, JCF ¼ 18 Hz, 1C), 116.2 (2C), 119.3 (q,
JCF ¼ 329 Hz, 2C, 2CF3), 124.9, 130.1 (2C), 139.0 (t, JCF ¼ 11
Hz, 1C), 141.4 (d, JCF ¼ 256 Hz, 1C), 142.2 (d, JCF ¼ 255 Hz,
1C), 145.6 (d, JCF ¼ 260 Hz, 1C), 147.3 (d, JCF ¼ 260 Hz, 1C),
ꢂ
ꢁ78 C, and the resulting mixture was allowed to warm to ꢁ20
ꢂC over a period of 1 h. To a solution of 3,5-bis(trifluoromethyl)-
phenyllithium19 generated in situ was added a solution of 1g (46
mg, 0.1 mmol) in Et2O (1 mL) at the same temperature, and the

1408 Bull. Chem. Soc. Jpn., 78, No. 8 (2005)
BCSJ AWARD ARTICLE
156.3. 19F NMR (282 MHz, CDCl3) ꢁ ꢁ150:6 (dd, J ¼ 9:0, 21.4
Hz, 1F), ꢁ149:3 (dd, J ¼ 9:2, 21.4 Hz, 1F), ꢁ141:1–ꢁ141:0 (m,
1F), ꢁ128:5 (dt, J ¼ 9:2, 21.4 Hz, 1F), ꢁ74:8 (s, 6F, 2CF3).
HRMS (FAB) calcd for C15H6F10O5S2: ½M þ 2Na ꢁ Hꢅþ
564.9214. Found: 564.9219.
2C), 142.5–142.7 (m, 2C), 145.5 (d, JCF ¼ 249 Hz, 2C), 147.1
(d, JCF ¼ 259 Hz, 2C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ154:7
(dd, J ¼ 6:1, 21.3 Hz, 2F), ꢁ153:5 (dd, J ¼ 6:1, 21.3 Hz, 2F),
ꢁ142:2–ꢁ142:1 (m, 2F), ꢁ129:7 (dt, J ¼ 9:3, 21.2 Hz, 2F),
ꢁ74:8 (s, 12F, 4CF3). HRMS(FAB) calcd for C22H10F20O10S4:
½M þ 3Na ꢁ 2Hꢅþ 1008.8374. Found: 1008.8391.
4-Trifluoroethoxy-2,3,5,6-tetrafluorophenylbis(triflyl)meth-
ane (7d): See Ref. 14c.
4,4-Bis[4-bis(triflyl)methyl-2,3,5,6-tetrafluorophenoxymeth-
yl]-1-cyclohexene (11c): IR (KBr) 2939, 1649, 1503, 1406,
Procedure for the Preparation of 4-Hydroxy-2,3,5,6-tetra-
fluorophenylbis(triflyl)methane (8). Pentafluorophenylbis(tri-
flyl)methane (0.22 g, 0.5 mmol) and potassium hydroxide (0.14
g, 2.5 mmol) were dissolved in t-BuOH (1.0 mL). The reaction
mixture was stirred for 3 h at reflux condition. After the mixture
was cooled to room temperature, it was diluted with H2O and
acidified with 4 M HCl. The resultant mixture was extracted with
Et2O. The organic layers were dried over magnesium sulfate, fil-
tered and concentrated under reduced pressure. Impurities were
removed by vacuum sublimation (10 Pa, 50 ꢂC) to give 8 in
66% yield. IR (KBr) 3464, 2912, 1530, 1510, 1216, 1109, 999,
1
1109, 1023, 616, 579, 499 cmꢁ1. H NMR (300 MHz, CDCl3) ꢁ
1.82 (t, J ¼ 6:3 Hz, 2H), 2.16 (br, 4H), 4.42 (d, J ¼ 9:3 Hz,
2H), 4.47 (d, J ¼ 9:3 Hz, 2H), 5.68 (d, J ¼ 10:0 Hz, 1H), 5.79
(d, J ¼ 10:0 Hz, 1H), 6.187 (s, 1H), 6.193 (s, 1H). 13C NMR
(125 MHz, CDCl3) ꢁ 21.1, 25.1, 29.0, 38.6, 70.8 (2C), 76.8 (t,
JCF ¼ 5:0 Hz, 2C), 94.8 (t, JCF ¼ 16:0 Hz, 2C), 119.2 (q, JCF
¼
328 Hz, 4C, 4CF3), 123.4, 126.6, 140.5 (d, JCF ¼ 250 Hz, 2C),
141.3 (d, JCF ¼ 250 Hz, 2C), 142.3–142.6 (m, 2C), 145.5 (d,
JCF ¼ 250 Hz, 2C), 147.2 (d, JCF ¼ 258 Hz, 2C). 19F NMR (282
MHz, CDCl3) ꢁ ꢁ154:7 (dd, J ¼ 6:2, 21.3 Hz, 2F), ꢁ153:9 (dd,
J ¼ 6:2, 21.3 Hz, 2F), ꢁ142:1–ꢁ142:0 (m, 2F), ꢁ129:7 (dt,
J ¼ 9:3, 21.3 Hz, 2F), ꢁ74:9 (s, 12F, 4CF3). HRMS (FAB) calcd
for C26H14F20O10S4: ½M þ 3Na ꢁ 2Hꢅþ 1060.8687. Found:
1060.8691.
957, 647, 624, 511 cmꢁ1 1H NMR (300 MHz, CDCl3) ꢁ 6.19
.
(s, 1H). 13C NMR (125 MHz, CD3OD) ꢁ 53.7–53.9 (m, 1C),
99.1 (t, JCF ¼ 19:1 Hz, 1C), 119.7 (q, JCF ¼ 325 Hz, 2C, 2CF3),
135.8–136.2 (m, 1C), 136.3 (d, JCF ¼ 227 Hz, 2C), 146.8 (d,
JCF ¼ 239 Hz, 2C). 19F NMR (282 MHz, CD3OD) ꢁ ꢁ167:1
(dd, J ¼ 6:1, 21.3 Hz, 2F), ꢁ139:6–ꢁ139:5 (m, 2F), ꢁ81:8 (s,
6F). HRMS (FAB) calcd for C9H2F10O5S2: ½M þ 2Na ꢁ Hꢅþ
488.8901. Found: 488.8885.
1,1-Bis[4-bis(triflyl)methyl-2,3,5,6-tetrafluorophenoxymeth-
yl]cyclohexane (11d): IR (KBr) 2938, 1650, 1505, 1407, 1347,
1
1224, 1112, 1022, 983, 615 cmꢁ1. H NMR (300 MHz, CDCl3) ꢁ
1.55–1.63 (m, 10H), 4.45 (s, 4H), 6.182 (s, 1H), 6.189 (s, 1H).
13C NMR (125 MHz, CDCl3) ꢁ 21.0 (2C), 25.8, 29.2 (2C), 39.8,
70.8 (2C), 76.8 (t, JCF ¼ 5:0 Hz, 2C), 94.8 (t, JCF ¼ 16:0 Hz,
2C), 119.2 (q, JCF ¼ 328 Hz, 4C, 4CF3), 140.4 (d, JCF ¼ 250
Hz, 2C), 141.3 (d, JCF ¼ 250 Hz, 2C), 142.4–142.7 (m, 2C),
145.5 (d, JCF ¼ 251 Hz, 2C), 147.5 (d, JCF ¼ 246 Hz, 2C).
19F NMR (282 MHz, CDCl3) ꢁ ꢁ154:5 (dd, J ¼ 6:1, 21.3 Hz,
2F), ꢁ153:2 (dd, J ¼ 6:1, 21.3 Hz, 2F), ꢁ142:1–ꢁ142:0 (m,
2F), ꢁ129:6 (dt, J ¼ 9:0, 22.5 Hz, 2F), ꢁ74:8 (s, 12F, 4CF3).
HRMS (FAB) calcd for C26H16F20O10S4: ½M þ 3Na ꢁ 2Hꢅþ
1062.8844. Found: 1062.8868.
General Procedure for the Preparation of Dibasic Acid 11.
To a solution of NaH (42 mg, 1.05 mmol, 60% oilꢂsuspension) in
pyridine (1.5 mL) was added diol (0.5 mmol) at 0 C. The result-
ing mixture was allowed to reach room temperature over a period
of 2 h. Lithium pentafluorophenylbis(triflyl)methanide (0.9 g, 2
mmol) was added to the mixture. The resulting mixture was heat-
ꢂ
ed at 70 C and stirred at the same temperature for 1 day before
the reaction was quenched with water at 0 ꢂC. The resultant mix-
ture was neutralized with 1 M aqueous HCl and washed with hex-
ane. The aqueous phase was acidified with 4 M aqueous HCl and
extracted with ether twice. The organic layers were dried over
magnesium sulfate, filtered and concentrated under reduced pres-
sure. Furthermore, any excess pentafluorophenylbis(triflyl)meth-
ane that was contained in the residue was removed by vacuum
General Procedure for Preparation of Dibasic Acid 13. To
a solution of dibromoarene (3.0 mmol) in THF (12 mL) was added
ꢂ
t-BuLi (13.2 mmol, 1.48 M pentane solution) at ꢁ78 C. The re-
sulting mixture was stirred under the following conditions: 13a
(ꢁ78 ꢂC, 1 h), 13b (ꢁ78 ꢂC, 1 h), and 13c (ꢁ78 ꢂC, 1 h to
ꢁ20 ꢂC, 0.5 h). Lithium pentafluorophenylbis(triflyl)methanide
(3.39 g, 7.5 mmol) was added to the mixture. The resulting mix-
ture wasꢂstirred under the followꢂing conditions: 13a (45 ꢂC, 19 h),
13b (50 C, 42 h), and 13c (50 C, 19 h) before the reaction was
quenched with water. The resulting mixture was washed with hex-
ane. The aqueous phase was acidified with 4 M aqueous HCl and
extracted with Et2O. The organic layer was dried over sodium sul-
fate, filtered and concentrated under reduced pressure. Further-
more, any excess pentafluorophenylbis(triflyl)methane that was
contained in the residue was removed by vacuum sublimation
ꢂ
sublimation (10 Pa, 100 C) to give 11. If the product was solid,
it was recrystallized from CHCl3–toluene.
1,3-Bis[1-bis(triflyl)methyl-2,3,5,6-tetrafluorophenoxy]pro-
pane (11a): IR (CHCl3) 1651, 1505, 1401, 1217, 1116, 1039,
1013, 980, 761 cmꢁ1. 1H NMR (300 MHz, CDCl3) ꢁ 2.38 (quintet,
J ¼ 5:9 Hz, 2H), 4.67 (t, J ¼ 5:9 Hz, 4H), 6.19 (s, 1H). 13C NMR
(125 MHz, CDCl3) ꢁ 30.4, 70.8 (2C), 70.9 (t, JCF ¼ 4:1 Hz, 2C),
94.8 (t, JCF ¼ 16:1 Hz, 2C), 119.2 (q, JCF ¼ 328 Hz, 4C, 4CF3),
140.4 (d, JCF ¼ 250 Hz, 2C), 141.2 (d, JCF ¼ 250 Hz, 2C),
142.0–142.2 (m, 2C), 145.5 (d, JCF ¼ 252 Hz, 2C), 147.2 (d,
JCF ¼ 245 Hz, 2C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ154:7 (dd,
J ¼ 6:2, 21.4 Hz, 2F), ꢁ153:5 (dd, J ¼ 6:2, 21.4 Hz, 2F),
ꢁ142:0–ꢁ141:9 (m, 2F), ꢁ129:5 (dt, J ¼ 9:0, 21.4 Hz, 2F),
ꢁ74:9 (s, 12F, 4CF3). HRMS(FAB) calcd for C21H8F20O10S4:
½M þ 3Na ꢁ 2Hꢅþ 994.8218. Found: 994.8214.
ꢂ
(10 Pa, 120 C). The crude product was purified by column chro-
matography on silica gel (AcOEt:hexane = 1:1 to 100:0 and then
AcOEt:AcOH = 10:1) to give dibasic acid as a solid. Finally, the
solid was reacidified with 4 M aqueous HCl.
1,4-Bis[1-bis(triflyl)methyl-2,3,5,6-tetrafluorophenoxy]bu-
tane (11b): IR (KBr) 2939, 1651, 1506, 1407, 1226, 1114, 1022,
4,5-Bis[4-bis(triflyl)methyl-2,3,5,6-tetrafluorophenyl]-2,7-di-
tert-butyl-9,9-dimethyl-9H-xanthene (13a):
IR(KBr) 1480,
1350, 1261, 1195, 1099, 1023, 800, 612 cmꢁ1 1H NMR (300
981, 618, 579, 499 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 2.08
.
(quintet, J ¼ 3:0 Hz, 4H), 4.54 (br, 4H), 6.19 (s, 1H), 6.20 (s,
1H). 13C NMR (125 MHz, CDCl3) ꢁ 21.0, 25.8, 29.2, 39.8, 70.8
(2C), 94.7 (t, JCF ¼ 15:9 Hz, 2C), 119.2 (q, JCF ¼ 328 Hz, 4C,
4CF3), 140.4 (d, JCF ¼ 250 Hz, 2C), 141.2 (d, JCF ¼ 250 Hz,
MHz, CD3OD) ꢁ 1.35 (s, 18H), 1.74 (s, 6H), 7.09 (br, 2H), 7.65
(d, J ¼ 2:4 Hz, 2H). 1H NMR (300 MHz, CDCl3) ꢁ 1.36 (s,
18H), 1.72 (s, 3H), 1.74 (s, 3H), 6.40 (s, 1H), 6.51 (s, 1H), 7.14
(br, 2H), 7.63 (d, J ¼ 1:8 Hz, 2H). 13C NMR (125 MHz, CDCl3)

A. Hasegawa et al.
Bull. Chem. Soc. Jpn., 78, No. 8 (2005) 1409
ꢁ 31.3 (6C), 31.5, 31.7, 33.1, 34.6, 34.9, 71.3, 72.1, 100.9 (m, 2C),
direct methods and expanded using Fourier techniques. 15035
reflections were independent and unique, and 9194 with I >
2ꢄðIÞ (2ꢅmax ¼ 29:16ꢂ) were used for the solution of the structure.
The non-hydrogen atoms were refined anisotropically. R ¼ 0:0775
and Rw ¼ 0:2184.
112.7, 112.9, 119.2 (q, JCF ¼ 328 Hz, 2C, 2CF3), 119.5 (q, JCF
¼
329 Hz, 2C, 2CF3), 124.2 (m, 2C), 125.1, 125.5, 127.7, 128.3,
130.5, 131.2, 144.0 (d, JCF ¼ 251 Hz, 2C), 144.7 (d, JCF ¼ 248
Hz, 4C), 145.6, 146.1, 146.3, 146.4 (t, JCF ¼ 263 Hz, 2C),
146.5. 19F NMR (282 MHz, CD3OD) ꢁ ꢁ143:6 (s, 4F), ꢁ135:5
(s, 4F), ꢁ80:4 (s, 6F, 2CF3), ꢁ80:2 (s, 6F, 2CF3). 19F NMR
(282 MHz, CDCl3) ꢁ ꢁ141:5 (br, 2F), ꢁ137:0 (m, 1F),
ꢁ136:4–ꢁ136:1 (m, 2F), ꢁ135:2 (m, 1F), ꢁ129:0 (m, 2F),
ꢁ75:9 (s, 6F), ꢁ72:9 (s, 6F). HRMS (FAB) calcd for
Crystallographic data have been deposited with the Cambridge
Crystallographic Data Centre: Deposition number CCDC-261827
and 261828 for compound 5 and 15. Copies of the data can be
obtained free of charge via http://www.ccdc.cam.ac.uk/conts/
retrieving.html (or from the Cambridge Crystallographic Data
Centre, 12, Union Road, Cambridge, CB2 1EZ, UK; Fax: +44
1223 336033; e-mail: deposit@ccdc.cam.ac.uk).
C41H30F20O9S4:
1240.9999.
4,6-Bis[4-bis(triflyl)methyl-2,3,5,6-tetrafluorophenyl]diben-
½M þ 3Na ꢁ 2Hꢅþ
1240.9990.
Found:
Procedure for the Esterification of 1-Octanol with
CF3SOCl.17 CF3SO2Na (2.5 g, 16 mmol) and mesitylenesulfo-
nyl chꢂloride (3.3 g, 15 mmol) were dissolved in MeCN (20 mL)
atꢂ25 C. After being stirred for 1 h, the mixture was cooled to
0 C and a solution of 1-octanol (1.6 mL, 10 mmol) and pyridine
(1.2 mL, 15 mmol) in MeCN (5 mL) was added dropwise. This
mixture was allowed to warm to room temperature, stirred for
12 h, diluted with Et2O (4 vols) and then washed 3 times with
H2O and once with saturated aq NaCl. The ether was dried over
magnesium sulfate, filtered and concentrated under reduced pres-
sure. The residue was purified by column chromatography using a
linear AcOEt gradient in hexane to give 17 as a colorless oil. IR
(neat) 2964, 2929, 2859, 1468, 1381, 1201, 1133, 940, 892, 751
zofuran (13b): IR (KBr) 2951, 1482, 1393, 1322, 1178, 1102,
976, 746, 626 cmꢁ1 1H NMR (300 MHz, CDCl3) ꢁ 6.32 (s,
.
1H), 6.33 (s, 1H), 7.60 (m, 4H), 8.22 (dd, J ¼ 2:1, 6.9 Hz, 2H).
13C NMR (125 MHz, CDCl3) ꢁ 70.7 (2C), 101.8 (t, JCF ¼ 14:6
Hz, 2C), 110.4 (2C), 119.2 (q, JCF ¼ 329 Hz, 4C, 4CF3), 121.4
(2C), 123.5 (2C), 123.7 (2C), 124.7 (2C), 129.4 (2C), 144.1 (d,
JCF ¼ 250 Hz, 2C), 144.9 (d, JCF ¼ 249 Hz, 4C), 146.6 (t, JCF
¼
244 Hz, 2C), 153.1 (2C). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ142:2
(br, 2F), ꢁ136:7 (m, 2F), ꢁ136:4 (m, 2F), ꢁ129:6 (br, 2F), ꢁ75:4
(s, 12F, 4CF3). HRMS (FAB) calcd for C20H8F20O9S4: ½M þ
3Na ꢁ 2Hꢅþ 1086.8268. Found: 1086.8252.
1,8-Bis[4-bis(triflyl)-2,3,5,6-tetrafluorophenyl]biphenylene
(13c): IR (KBr) 2932, 1492, 1403, 1352, 1318, 1199, 1117, 972,
cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 0.89 (t, J ¼ 6:8 Hz, 3H),
1
613 cmꢁ1. H NMR (300 MHz, CD3OD) ꢁ 6.74 (d, J ¼ 8:1 Hz,
1.29–1.33 (m, 10H), 1.76 (quintet, J ¼ 6:7 Hz, 2H), 4.11–4.18
(m, 1H), 4.36 (dt, J ¼ 6:6, 9.9 Hz, 1H). 13C NMR (75 MHz,
CDCl3) ꢁ 14.0, 22.6, 25.3, 28.9, 29.0, 29.7, 31.7, 69.2, 122.8 (q,
JCF ¼ 337 Hz, 1C, CF3). 19F NMR (282 MHz, CDCl3) ꢁ ꢁ79:3
(s, 3F, CF3).
2H), 6.81 (d, J ¼ 6:9 Hz, 2H), 6.94 (dd, J ¼ 6:9, 8.1 Hz, 2H).
19F NMR (282 MHz, CD3OD) ꢁ ꢁ145:7 (m, 4F), ꢁ134:9 (br,
4F), ꢁ80:9 (s, 12F, 4CF3). HRMS (FAB) calcd for
C30H8F20O8S4: ½M þ 3Na ꢁ 2Hꢅþ 1070.8319. Found: 1070.8339.
Procedure for the Preparation of N,N0-Octamethylenedi-
pyridinium Dibenzofuran-4,6-diylbis(2,3,5,6-tetrafluoro-1,4-
Procedure for the Preparation Octyl Trifluoromethyl Sul-
fone (18).17 Compound 17 (2.1 g, 8.7 mmol) was dissolved in
HMPA (8 mL). The reaction mixture was heated under an Ar at-
mosphere at 145 ꢂC for 12 h. After the mixture was cooled, it was
diluted with Et2O (20 mL) and washed with H2O and saturated
NaHCO3. The organic layers were dried over magnesium sulfate,
filtered and concentrated under reduced pressure. The residue was
purified by column chromatography using a linear EtOAc gradient
in hexane to give a brown oil. The oil was then subjected to vacu-
um sublimation (15 Pa, 80 ꢂC) to give 18 as a colorless oil. IR
phenylene)bis[bis(triflyl)methanide] (15).
To a solution of
N,N0-octamethylenedipyridinium dibromide (129 mg, 0.30 mmol)
in H2O–THF 2:1 (2 mL:1 mL), dilithium dibenzofuran-4,6-
diylbis(2,3,5,6-tetrafluoro-1,4-phenylene)bis[bis(triflyl)methanide]
(129 mg, 0.30 mmol) was added at room temperature and the mix-
ture was stirred under reflux condition for 1 d. After the mixture
was cooled to ambient temperature, the solvent was evaporated.
The crude product was washed with H2O and EtOAc several times
and dried under reduced precessure (80 ꢂC, 0.7 kPa, overnight) to
give 15 in 84% yield. IR (KBr) 3093, 2936, 1636, 1478, 1351,
(neat) 2957, 2930, 2860, 1468, 1366, 1198, 1123, 617 cmꢁ1
.
1H NMR (300 MHz, CDCl3) ꢁ 0.81 (t, J ¼ 6:9 Hz, 3H), 1.21–
1.27 (m, 8H), 1.41 (quintet, J ¼ 7:3 Hz, 2H), 1.87 (quintet, J ¼
7:8 Hz, 2H), 3.14 (dd, J ¼ 8:1, 8.1 Hz, 2H). 13C NMR (75
MHz, CDCl3) ꢁ 13.9, 20.6, 22.5, 28.3, 28.7 (2C), 31.6, 49.5,
119.4 (q, JCF ¼ 325 Hz, 1C, CF3). 19F NMR (282 MHz, CDCl3)
ꢁ ꢁ79:0 (s, 3F, CF3).
1172, 1020, 973, 610 cmꢁ1 1H NMR (300 MHz, DMSO-d6) ꢁ
.
1.27 (m, 8H), 1.90 (m, 4H), 4.57 (t, J ¼ 7:2 Hz, 4H), 7.62 (t, J ¼
7:8 Hz, 2H), 7.74 (d, J ¼ 6:9 Hz, 2H), 8.16 (t, J ¼ 6:9 Hz, 4H),
8.44 (d, J ¼ 6:3 Hz, 2H), 8.61 (t, J ¼ 6:3 Hz, 2H), 9.06 (d, J ¼
5:4 Hz, 4H). 13C NMR (125 MHz, DMSO-d6) ꢁ 25.5 (2C), 28.4
(2C), 30.8 (2C), 55.5 (2C), 60.9 (2C), 111.2 (2C), 112.4 (2C),
115.9 (2C), 120.9 (q, JCF ¼ 325 Hz, 4C, 4CF3), 123.8 (2C),
Procedure for the Preparation 1-Bis(triflyl)octane (19). To
a solution of 18 (0.49 mmol) in dry Et2O (1 mL) was added t-BuLi
(0.39 mL, 0.54 mmol, 1.41 M solution in hexane) dropwise at ꢁ78
ꢂC, and the resulting mixture was stirred for 20 min. Triflic anhy-
dride (46 mL, 0.27 mmol) was then added, and the resulting mix-
ture was allowed to warm to room temperature over a period of 3
124.1 (2C), 124.4 (2C), 128.2 (4C), 130.6 (2C), 143.2 (d, JCF
¼
246 Hz, 4C), 144.9 (4C), 145.7 (2C), 147.6 (d, JCF ¼ 244 Hz,
4C), 152.9 (2C). 19F NMR (282 MHz, DMSO-d6) ꢁ ꢁ145:0 (br,
4F), ꢁ137:8 (br, 4F), ꢁ82:1 (s, 12F, 4CF3).
ꢂ
X-ray Crystallographic Analysis of 15:
Crystal data:
h. After the reaction mixture was cooled to ꢁ78 C, t-BuLi (0.39
C
50:43H35F20:43N3O10S4, Mw ¼ 1359:18, crystal dimensions
mL, 0.54 mmol, 1.41 M in hexane) was added dropwise, and the
resulting mixture was stirred for 20 min. Triflic anhydride (0.27
mmol) was then added, and the resulting mixture was allowed
to room temperature over a period of 1 h before the reaction
was quenched with water. The resultant mixture was neutralized
and washed with hexane. The aqueous phase was acidified with
4 M aqueous HCl and extracted with Et2O twice. The organic lay-
0:50 ꢃ 0:40 ꢃ 0:20 mm3, orthorhombic, space group Pbca
ꢀ
(#61), a ¼ 14:6941ð17Þ, b ¼ 22:460ð2Þ, c ¼ 34:073ð4Þ A, V ¼
11245ð2Þ A , Z ¼ 8, Dc ¼ 1:606 g/cm , ꢂ ¼ 0:296 mmꢁ1, T ¼
3
ꢀ 3
173 K. X-ray crystallographic analysis was performed with a
Bruker SMART APEX diffractometer (graphite monochromator,
ꢀ
Mo Kꢀ radiation, ꢃ ¼ 0:71073 A). The structure was solved by

1410 Bull. Chem. Soc. Jpn., 78, No. 8 (2005)
BCSJ AWARD ARTICLE
ers were dried over magnesium sulfate, filtered and concentrated
under reduced pressure to give 19. IR (neat) 2964, 2933, 2860,
7
For Me3SiNTf2-promoted reactions, see: a) B. Mathieu
and L. Ghosez, Tetrahedron Lett., 38, 5497 (1997). b) A. Ishii, O.
Kotera, T. Saeki, and K. Mikami, Synlett, 1997, 1145. c) G.
Simchen and S. Jonas, J. Prakt. Chem./Chem.-Ztg., 340, 506
(1998). d) B. Mathieu and L. Ghosez, Tetrahedron, 58, 8219
(2002).
1468, 1395, 1212, 1117, 693, 591 cmꢁ1 1H NMR (300 MHz,
.
CDCl3) ꢁ 0.79 (t, J ¼ 6:8 Hz, 3H), 1.20–1.26 (m, 8H), 1.63 (quin-
tet, J ¼ 7:7 Hz, 2H), 2.35 (dd, J ¼ 6:3, 15.3 Hz, 2H), 4.74 (t, J ¼
5:6 Hz, 1H). 13C NMR (75 MHz, CDCl3) ꢁ 13.8, 22.5, 25.4, 27.2,
28.4, 28.9, 31.5, 77.5, 119.3 (q, JCF ¼ 328 Hz, 2C, 2CF3).
19F NMR (282 MHz, CDCl3) ꢁ ꢁ74:1 (s, 6F, 2CF3). HRMS
(FAB) calcd for C10H5F9O2S: ½M þ Hꢅþ 379.0472. Found:
379.0489.
8
For M(CTf3)3-promoted reactions, see: F. J. Waller, A. G.
M. Barrett, D. C. Christopher, D. Ramprasad, R. M. McKinnell,
A. J. P. White, D. J. Williams, and R. Ducray, J. Org. Chem.,
64, 2910 (1999).
9
V. M. Vlasov, J. Org. Chem., 63, 7868 (1998).
10 B. M. Rode, A. Engelbrecht, and J. Z. Schantl, J. Prakt.
Chem., 253, 17 (1973).
11 a) R. J. Koshar and R. A. Mitsch, J. Org. Chem., 38, 3358
(1973). b) S.-Z. Zhu, Heteroat. Chem., 5, 9 (1994). c) S.-Z. Zhu,
J. Fluorine Chem., 64, 47 (1993).
12 K. Ishihara, A. Hasegawa, and H. Yamamoto, J. Fluorine
Chem., 106, 139 (2000).
I. Leito, I. Kaljurand, I. A. Koppel, L. M. Yagupolskii, and
We thank Central Glass Co., Ltd., for a generous gift of
CF3SO2Na. A.H. also acknowledges a JSPS Fellowship for
Japanese Junior Scientists. Financial support for this project
was provided by SORST, Japan Science and Technology
Agency (JST), MEXT.KAKENHI (No. 16033228), the Shorai
Foundation for Science and Technology, the Ogasawara Foun-
dation for the Promotion of Science & Engineering, and the
Iketani Science and Technology Foundation. We also ac-
knowledge Dr. Manabu Hatano for the single-crystal X-ray
analysis.
13 n-BuLi could be used instead of t-BuLi. For example, 1g
was obtained in 83% yield (based on triflic anhydride) when n-
BuLi was used instead of t-BuLi.
14 a) K. Ishihara, A. Hasegawa, and H. Yamamoto, Angew.
Chem., Int. Ed., 40, 4077 (2001). b) K. Ishihara, A. Hasegawa,
and H. Yamamoto, Synlett, 2001, 1296. c) K. Ishihara, A.
Hasegawa, and H. Yamamoto, Synlett, 2001, 1299. d) A.
Hasegawa, K. Ishihara, and H. Yamamoto, Angew. Chem., Int.
Ed., 42, 5731 (2003).
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4
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5
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6
L. Turowsky and K. Seppelt, Inorg. Chem., 27, 2135
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