The activation of carbon-chlorine bonds in per- and polyfluoroalkyl chlorides: DMSO-induced hydroperfluoroalkylation of alkenes and alkynes with sodium dithionite

Article abstract of DOI:10.1021/jo9900937

In DMSO, the addition reactions of perfluoroalkyl chlorides, R(F)Cl, to alkenes or alkynes can occur smoothly in the presence of 1.5 equiv of Na₂S₂O₄ and NaHCO₃ at 75-80 °C for 4-10 h to give the corresponding adducts (RCH₂CH₂RF or RCH = CHR(F)). Ethyl chlorofluoro- (1f), chlorodifluoro- (1g) acetates, even nonfluorinated compounds, such as ethyl dichloro- (1h), chloro- (1i) acetates, and chloroform (1j) can undergo the similar reaction. Treatment of ω-iodo (or chloro-) perfluoroalkyl chlorides [X(CF₂)(n) Cl, n = 2, 4, X= I or Cl] with > 3 equiv of alkenes and Na₂SO₄ gives directly the symmetrically disubstituted alkanes (RCH₂CH₂)₂(CF₂)(n). The symmetrically and unsymmetrically disubstituted adducts RCH₂CH₂(CF₂)(n)CH₂CH₂R' from ω-iodoperfluoroalkyl chlorides can be also obtained stepwise, i.e., through the further addition reactions of monoadducts, RCH₂CH₂(CF₂)(n)Cl to olefins. However, for α,ω- dichloroperfluoroalkanes, the similarly stepwise reactions with an alkene is not clean, both bis-adducts and the corresponding ω-hydrides, RCH₂CH₂(CF₂)(n)H as byproducts are also formed. In the absence of alkenes or alkynes, per- and polyfluoroalkyl chlorides can be converted to their sulfinate salts and sulfonyl chlorides.

Full text of DOI:10.1021/jo9900937

J . Org. Chem. 1999, 64, 4775-4782
4775
Th e Activa tion of Ca r bon -Ch lor in e Bon d s in P er - a n d
P olyflu or oa lk yl Ch lor id es: DMSO-In d u ced
Hyd r op er flu or oa lk yla tion of Alk en es a n d Alk yn es w ith Sod iu m
Dith ion ite
Zheng-Yu Long and Qing-Yun Chen*
Laboratory of Fluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of
Sciences, 354 Fenglin Lu, 200032 Shanghai, China
Received J anuary 19, 1999 (Revised Manuscript Received April 15, 1999)
In DMSO, the addition reactions of perfluoroalkyl chlorides, RFCl, to alkenes or alkynes can occur
smoothly in the presence of 1.5 equiv of Na2S2O4 and NaHCO3 at 75-80 °C for 4-10 h to give the
corresponding adducts (RCH2CH2RF or RCHdCHRF). Ethyl chlorofluoro- (1f), chlorodifluoro- (1g)
acetates, even nonfluorinated compounds, such as ethyl dichloro- (1h ), chloro- (1i) acetates, and
chloroform (1j) can undergo the similar reaction. Treatment of ω-iodo (or chloro-) perfluoroalkyl
chlorides [X(CF2)nCl, n ) 2, 4, X) I or Cl] with >3 equiv of alkenes and Na2S2O4 gives directly the
symmetrically disubstituted alkanes (RCH2CH2)2(CF2)n. The symmetrically and unsymmetrically
disubstituted adducts RCH2CH2(CF2)nCH2CH2R′ from ω- iodoperfluoroalkyl chlorides can be also
obtained stepwise, i.e., through the further addition reactions of monoadducts, RCH2CH2(CF2)nCl
to olefins. However, for R,ω-dichloroperfluoroalkanes, the similarly stepwise reactions with an alkene
is not clean, both bis-adducts and the corresponding ω-hydrides, RCH2CH2(CF2)nH as byproducts
are also formed. In the absence of alkenes or alkynes, per- and polyfluoroalkyl chlorides can be
converted to their sulfinate salts and sulfonyl chlorides.
In tr od u ction
prepared which are useful agents for transferring alde-
hydes to difluoromethylated alcohols in two steps.5
Per- and polyfluoroalkyl halides are useful industrial
sources of many fluorine-containing materials.1 Among
them, simple bromides and chlorides are thermally and
chemically inert and, thus, used as fire extinguishants
(e.g., Halon 1301, CF3Br; Halon 1211, CF2BrCl), refriger-
ants (e.g., CFC-12, CF2Cl2; CFC-115, CF3CF2Cl), aerosol
propellants (e.g., CFC-11, CFCl3) or cleaning solvents
(e.g., CFC-113, ClCF2CFCl2).2 However, chlorine or bro-
mine atoms, released from long-lived CFCs or Halons by
the action of short wavelength solar ultraviolet radiation,
causes the depletion of ozone layer. In line with the
Montreal Protocol, the production of Halons and CFCs
should be stopped since 1994 and 1996, respectively.3
Along with the appearance of the CFCs and Halons
alternatives, there are a quite number of reports on
converting CFCs and Halons to useful fluorinated com-
pounds. For example, dibromodifluoromethane was uti-
lized in reductive reactions with olefins to provide 1:1
adducts.4 Using CF2Br2 or CF2BrCl as the starting
materials, Me3SiCF2X (X ) Cl, Br) compounds were
Conversion of chlorofluorocarbons into the correspond-
ing hydropoly-fluorocarbons has attracted much attention
because of the latter being the potential CFC replace-
ments. Zinc powder in the presence of catalytic amount
of nickel dichloride can reduce perfluoroalkyl chloride to
the corresponding hydride in high yields.6 Reduction of
ω-chloroperfluoroalkyl iodides by lithium aluminum hy-
dride in ether at room temperature for several hours not
only gives ω-chloroperfluoroalkyl hydrides but also R,ω-
dihydroperfluoroalkanes.7 Palladium-catalytized hydro-
genation8 or electrochemical reduction of CF2Cl29 results
in difluoromethane (HFC-32, CF2H2), an excellent new
refrigerant.10 Selective hydrogenolysis of CF3CCl3 (CFC-
113a) with group VIII transition metal complexes pro-
duces CF3CHCl2 (HCFC-123)11 which reacts with zinc
and aldehyde to give the corresponding alcohol through
organozinc intermediates.12 Besides the organometallic
reductants, such as organotin hydrides,13 organosilicon-
hydrides [e.g., HSi(C2H5)3] were reported very recently
as selective reductants of halopolyfluorocarbons [e.g.,
(1) (a) Chambers, R. D. Fluorine in Organic Chemistry; Wiley-Inter-
Science: New York, 1973. (b) Hudlicky, M. Chemistry of Organic
Fluorine Compounds; 2nd ed.; Ellis, Horwood: Chichester, England,
1976.
(2) (a) Powell, R. L. Refrigerants, propellants and foam-Blowing
Agents. In Chemistry of Organic Fluorine Compounds II, Hudlicky,
M., Ed.; American Chemical Society, Wishington, DC, 1995. (b) Banks,
R. E., Smart, B. E., Tatlow, J . C., Eds.; Organofluorine Chemistry:
Principle and Commercial Applications; Plenum Press: New York,
1994.
(5) Yudin, A. K.; Prakash, G. K. S.; Deffieux, D.; Bradley, M.; Bau,
R.; Olah, G. A. J . Am. Chem. Soc. 1997, 119, 1572.
(6) Chen, Q.-Y.; W, J .-P. Chinese J . Chem. 1991, 9, 181.
(7) Chen, Q.-Y.; Chen, M.-F. J . Fluorine Chem. 1990, 49, 107.
(8) Cog, B.; Cognion, J . M.; Figneras, D.; Tourigant, D. J . Catal.
1993, 141, 21.
(9) Delli, E.; Kouloumtzoglou S.; Kyriacou, G.; Lambrou, C. J . Chem.
Soc., Chem. Commun. 1998, 1693.
(10) Chem. Ind. 1991, 18, 31.
(3) (a) Banks, R. E. J . Fluorine Chem. 1994, 67, 193. (b) Franciso,
J . S.; Maricq, M. M. Acc. Chem. Res. 1996, 29, 391.
(4) (a) Burton, D. J .; Kehoe, L. J . Tetrahedron Lett. 1966, 5163. (b)
Maruoka, K.; Sano, H.; Fukutani, Y.; Yamamoto, H. Chem. Lett. 1985,
1689. (c) Hu, C.-M.; Chen, J . J . Chem. Soc., Chem. Commun. 1993,
72.
(11) Cho, O. J .; Lee, I. M.; Park, K. Y.; Kim, H. S. J . Fluorine Chem.
1995, 71, 107.
(12) Tamura, M.; Kekiya, A. J . Fluorine Chem. 1995, 71, 119.
(13) Van, D. P. M.; Belter, R. K.; Borouski, R. J .; Ellis, L. A. S.;
Pershichini, P. J ., III; Poss, A. J .; Rygas, T. P.; Tung, H. S. J . Fluorine
Chem. 1995, 71, 59 and references therein.
10.1021/jo9900937 CCC: $18.00 © 1999 American Chemical Society
Published on Web 06/09/1999

4776 J . Org. Chem., Vol. 64, No. 13, 1999
Long and Chen
ClCF2CFCl2, CF3CFClCF2Cl, and (CF3)2CCl2].14 The order
of decreasing activity of different groups in the reduction
is -CCl2- > -CClF- > -CClH- > -CF2Cl. Besides the
ability of hydrogenolysis as mentioned above, the carbon-
chlorine bond in perfluoroalkyl chloride, RFCF2Cl, is
hardly functionized by other groups.15 A special analogue,
chlorodifluoromethylbenzene (C6H5CF2Cl), was reduced
with SmI2/HMPA to C6H5CF2H (major) through the
induction of a simultaneously anionic addition to ketones
giving the corresponding alcohols (minor).16 More impor-
tantly, progress in this area was made with the sulfina-
todehalogenation of perhalocarbons, which was discov-
ered and developed by Huang and co-workers.17 Using
inexpensive sulfur-containing reductants (e.g., Na2S2O4)
under mild conditions, per- and polyfluoroalkyl halides
(RFX, X ) Br, I; RFCCl3) can smoothly give the corre-
sponding sulfinate salts. The sulfinates may be readily
converted to perfluoroalkanesulfonyl halides, acids, and
their derivatives. More interestingly, this method has
been widely applied to perfluoroalkylate alkenes, dienes,
allenes, alkynes, and aromatics. However, this system
is confined to perhalocarbons and cannot be applied to
perfluoroalkyl chlorides, i.e., RFCF2Cl.18 For example,
tetrachloromethane afforded the desired product, CCl3-
SO2Na, with high yield while chloroform was shown to
be completely inert.19 Only recently, it was found that
the difluoromethylation of alkenes and alkynes with
iododifluoromethane could occur under the standard
sulfinatodehalogenation conditions.20 When we extended
this method to 2,2,2-trifluoroethyl halides, the iodide and
bromide could be smoothly sulfinatodehalogenated with
sodium dithionite in CH3CN/H2O at 40-60 °C for 10 h,
while the chloride (CF3CH2Cl, HCFC-133a) was com-
pletely inert.21 To our surprise, if using dimethyl sulfoxide
(DMSO) as a solvent instead of CH3CN/H2O, CF3CH2Cl
could also be converted to the sulfinate and trifluoro-
ethylate alkenes and alkynes.22 The tremendous role of
Sch em e 1a
a
RF ) n-C4F9 (a ), H(CF2)4 (b), H(CF2)6 (c), CF3CH2, (d ), ClCF2
(e), CFHCO2Et (f), CF2CO2Et (g), ClCHCO2Et (h ), CH2CO2Et (i),
HCCl2 (j), CF2ClCFCl (k ). R ) n-C4H9 (a ), n-C5H11 (b), n-C6H13
(c), n-C7H15 (d ), CH2OCH2CHdCH2 (e), c-C4H8 (f), CH2OAc (g),
SiMe3 (h ), CH2OC2H5 (i), CH2OH (j).
Sch em e 2
Sch em e 3
solvent promoted us to examine the sulfinatodehaloge-
nation possibility of per- and polyfluoroalkyl chlorides.
We were fortunate to find the positive results not only
for perfluoroalkyl chlorides but also for some nonfluori-
nated ones.23 This paper presents our observation.
Resu lts a n d Discu ssion
1. Hyd r op er flu or oa lk yla tion of Alk en es w ith P er -
a n d P olyflu or oa lk yl Ch lor id es. It was found that per-
and polyfluoroalkyl chlorides 1 can smoothly react with
alkenes 2 in DMSO in the presence of sodium dithionite
and sodium bicarbonate (1:2:Na2S2O4:NaHCO3 ) 1:1.5:
1.5:1.5) at 75-80 °C for 4-6 h to give the corresponding
chlorine-free monoadducts 3 in good yields (see Scheme
1).
The addition products 3be, 3ce, 3ge, 3je, and 3k e from
the chlorides and 2e are the tetrahydrofuran derivatives,
indicative of a free radical intermediate.24 The cis- and
trans- configuration of 3e can be assigned by comparing
(14) Petrov, V. A. J . Org. Chem. 1998, 63, 7294.
(15) (a) The C-Cl bond in a CF2Cl group can be weakened by an
activating neighboring group, such as chlorodifluoromethylsilanes,5
chlorodifluoromethyl enol ethers (Rajaonah, M.; Rock, M. H.; J ean-
Pierre, Begue; Bonnet-Delpon, D.; Condon, S.; J ean-Yves N. Tetrahe-
dron Lett. 1998, 39, 3137.), chlorodifluoroesters (Lang, R. W.; Schaub,
B. Tetrahedron Lett. 1988, 29, 2943 and references therein), and
chlorodifluoromethylated ketones (Burkholder, C.; Dolbier, W. R. J r;
1
the H NMR chemical shift of -CH3 (cis- < trans-) (see
-
Scheme 2).24b
Medebielle, M.; Ndedi, A. Tetrahedron Lett. 1998, 39, 8853.). The CF2
anion equivalents generated from these compounds by electrochemical
metal catalyzed methods or by electron-donor tetrakis(dimethylamino)-
ethylene stimulation can be trapped by aldehydes and ketones to give
the corresponding alcohols. (b) The attack of sulfur, oxygen and
nitrogen nucleophiles on CF2ClCCl2F, CF2ClCCl3 has been established
as a halophilic rather than SN2 or single electron-transfer mechanism,
the products derived are involved in the olefin intermediates (Li, X.-
Y.; J iang, X.-K.; Pan, H.-Q.; Hu, J .-S.; Fu, W.-M. Pure Appl. Chem.
1987, 59, 1015.).
Interestingly, ethyl chlorofluoro- (1f), chlorodifluoro-
(1g), and even nonfluorinated compounds, such as dichlo-
ro- (1h ), chloro-(1i) acetates, and chloroform (1j) can
undergo the similar reaction. Notably, for synthesizing
R-fluoro or R,R-difluoroacetates and amides, the starting
material chlorocompounds need not be converted first to
the corresponding iodides before reduction as previous
works did;25 thus, this method seems to be more straight-
forward (see Scheme 3).
(16) Yoshida, M.; Suzuki, D.; Tyoda, M. J . Chem. Soc., Perkin Trans.
1 1997, 643.
(17) (a) Huang, W.-Y.; Huang, B.-N.; Wang, W. Acta Chim. Sin.
(Chin. Ed.) 1983, 41, 1193. (b) Huang, B.-N.; Wang, B.-H.; Wang, W.;
Huang, W.-Y. Acta Chim. Sin. (Engl. Ed.) 1986, 1, 68. (c) Huang, W.-
Y.; Huang, B.-N.; Wang, W. Acta Chim. Sin. (Engl. Ed.) 1984, 2, 188.
(d) Huang, W.-Y.; Huang, B.-N.; Wang, W. Acta Chim. Sin. (Engl. Ed.)
1985, 3, 253. (e) Huang, W.-Y.; Chen, J .-L. Acta Chim. Sin. (Engl. Ed.)
1985, 4, 376.
Both dichlorodifluoromethane (1e) and 1,1,2-trifluo-
rotrichloroethane (1k ) can readily give the monohydro-
perfluoroalkylated products in the presence of equiva-
(18) (a) Huang, W.-Y.; Wang, W.; Huang, B.-N. Acta Chim. Sin.
(Chin. Ed.) 1985, 43, 409. (b) Huang, W.-Y.; Lu, L.; Zhang, Y.-F. Chin.
J . Chem. 1990, 4, 350. (c) Huang, W.-Y.; Zhang, H.-Z. Chin. J . Chem.
1991, 1, 76.
(19) Huang, W.-Y.; Huang, B.-N.; Chen, J .-L. Acta Chim. Sin. (Chin.
Ed.) 1986, 44, 45.
(20) Cao, P.; Duan, J .-X.; Chen, Q.-Y. J . Chem. Soc., Chem. Commun.
1994, 737.
(21) Long, Z.-Y.; Chen, Q.-Y. Tetrahedron Lett. 1998, 39, 8487.
(22) (a) Long, Z.-Y.; Chen, Q.-Y. PRC Patent CN 98110884.9. (b)
Long, Z.-Y.; Chen, Q.-Y. PRC Patent CN 98110883.0.
(23) (a) Long, Z.-Y.; Chen, Q.-Y. Patent: CN 98122019.3. (b) Long,
Z.-Y.; Chen, Q.-Y. PRC Patent CN 98122021.5.
(24) (a) Chen, Q.-Y. Single electron-transfer reaction of perfluoro-
alkyl iodides. In Organofluorine Chemistry in China; Huang, W. Y.,
Ed.; Shanghai Science and Technology Press: Shanghai, 1996; Chapter
5, p 112. (b) Chen, Q.-Y. Yang, Z.-Y. J . Fluorine Chem. 1985, 28, 399.
(25) (a) Zhi, C.-X.; Chen, Q.-Y. J . Chem. Soc., Perkin Trans. 1 1996,
1741. (b) Wang, Y.; Yang, Z.-Y.; Burton, D. J . Tetrahedron Lett. 1992,
33, 2137. (c)Yang, Z.-Y.; Burton, D. J . J . Fluorine Chem. 1989, 45, 435.
(d) Yang, Z.-Y.; Burton, D. J . J . Org. Chem. 1991, 56, 5125. (e) Huang,
W.-Y.; Lu, L.; Zhang, Y.-F. Chin. J . Chem. 1990, 1, 68.

Activation of Carbon-Chlorine Bonds
J . Org. Chem., Vol. 64, No. 13, 1999 4777
Ta ble 1. Rea ction of RF Cl w ith Alk en es in DMSOa
Sch em e 5
entry RFClb alkene T °C time (h)
3. yield %c
1
2
3
4
5
6
7
8
9
1a
2c
2d
2f
2a
2c
2d
2e
2f
2a
2c
2d
2e
2f
75
75
70
70
80
75
70
70
75
75
75
75
75
90
90
90
75
75
75
75
75
75
75
70
70
75
75
79
80
75
75
80
80
80
80
75
60
60
60
55
6
6
5
6
4
6
6
6
5
6
6
6
6
10
10
10
6
8
6
6
7
7
7
6
6
6
6
6
6
7
10
6
5
4
4
6
80
81
71
63
80
88
1b
Ta ble 2. Rea ction of ω-Iod o (or Ch lor o) P er flu or oa lk yl
Ch lor id es w ith Alk en es in DMSO
(RF Cl:2:Na 2S2O4:Na HCO3 ) 1:3:3:3)
RFCl alkene T °C time(h) converted %a product yield %b
76(cis:trans ) 2.3:1)e
72
82
80
82
1c
1d
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
4
4
5
5
7
8
8
2a
2c
2a
90
85
90
90
40
95
90
10
10
10
12
2
100
100
90
88
100
90
6a
6c
6a
6c
8
73
65
54
50
72
52
60
70(cis:trans ) 2.3:1)e
78
58
70
86
74
71
63
82
2a d
2cd
2cd
2c
2d
2f
2h
2i
2b
2c
2e
2f
2g
2h
2a
2c
2f
2g
2a
2c
2e
2g
2j
2c
2k c
2a c
2cc
1e
1f
10
10
9a
9c
80
a
b
The conversion determined by 19F NMR. The isolated yields
based on RFCl and in addition to 5-10% of RFH. c RFCl:2:Na2SO4:
NaHCO3 ) 1:1.5:1.5:1.5.
75
80
78
1g
Sch em e 6
73(cis:trans ) 3:1)e
88
68
62
60
71
65
45
83
1h
1i
1j
89
react further with the same or different alkene to afford
bis-substituted one. For example, treatment of â-iodo-
tetrafluoroethyl chloride (7) with 4-acetyl-butene-1 (2k )
in the presence of 1.5 equiv of Na2S2O4 in DMSO at 40
°C for 2 h to give the corresponding monoadduct (8). This
new adduct can react further with hexene-1 (2a ) or
octene-1 (2c) to afford the unsymmetrically bis-adduct
(9) with a small amount of the hydride as byproduct (see
Scheme 5).
73(cis:trans ) 4:1)e
70
61
74
1k
2a
2e
2f
6
6
6
6
48(cis:trans ) 1:1)e
69
63
2g
a
b
1:2:Na2S2O4:NaHCO3 ) 1:1.5:1.5:1.5. The conversion of RFCl
was 100% (determined by 19F NMR). c The isolated yields were
d
based on RFCl and a trace of RFH was also obtained. In a sealed
ampoule. e The ratio of cis/trans based on the 1H NMR.
However, unlike the ω-iodoperfluoroalkyl chlorides, the
R,ω-dichloroperfluoroalkanes (e.g., 5) are unable to react
stepwise cleanly with olefin and both the bis-adduct and
the corresponding ω-hydride as byproducts were obtained
despite only using 1.5 equiv of starting materials. The
results are shown in Table 2. (See also Scheme 6.)
Sch em e 4
Y ) I (4)
R ) n-C4H9 (a ), n-C6H13 (c)
3. Hyd r op er flu or oa lk yla tion of Alk yn es w ith P er -
a n d P olyflu or oa lk yl Ch lor id es. Similar to alkenes,
alkynes reacted with perfluoroalkyl chlorides in the
presence of 1.5 equiv. of Na2S2O4 in DMSO at 75-80 °C
for 7-10 h to give the corresponding E/Z mixtures of
perfluoroalkylated alkene in 45-76% yields and a small
amount of RFH (10-15%). The E and Z isomers were
determined by comparing the chemical shifts of the
-CF 2CHdCHR in their respective 19F NMR spectra, the
downfield signal being assigned to Z-isomer and the
upfield being assigned to E-isomer.26 The stereochemistry
of 11gd was designated E-isomer on the basis of the coup-
ling constant between the vinyl protons (3J H,H ) 15.8 Hz).
The results are shown in Table 3. (See also Scheme 7.)
Y ) Cl (5)
lents of alkene and Na2S2O4. For the former, dihydroper-
fluoroalkylated derivatives (RCH2CH2)2CF2 have never
been obtained despite using large excess of alkenes and
Na2S2O4, while for the latter, one of chlorine at the end
group of -CFCl2 was smoothly substituted and the
reaction became complicated when employing large ex-
cess of Na2S2O4. All the results are listed in Table 1.
2. Bish yd r op er flu or oa lk yla tion of Alk en es w ith
ω-Iod o (or ch lor o)P er flu or oa lk yl Ch lor id es. When
ω-iodo (or chloro) perfluoroalkyl chlorides 4 and 5 were
treated with >3 equivalents of alkenes and Na2S2O4 in
DMSO, the symmetrically disubstituted alkanes 6 were
obtained directly (see Scheme 4).
4. Th e Syn th esis of Sod iu m P er flu or oa lk a n esu lfi-
n a tes a n d Th eir Der iva tives fr om P er flu or oa lk yl
Ch lor id es a n d Na 2S2O4. Perfluoroalkyl chlorides 1 can
be easily converted to the corresponding sulfinate salts
12 with Na2S2O4/NaHCO3 in DMSO at 75 °C for 8 h. Both
the conversion and yield are high (>80%) as shown by
19F NMR spectroscopy. The isolation of the sulfinate salts
The same disubstituted products from ω-iodoperfluo-
roalkyl chlorides can be formed stepwise, i.e., monosub-
stituted perfluoroalkyl chloride, formed in the presence
of equivalents of starting materials (ω-iodoperfluoroalkyl
chloride:alkene:Na2S2O4:NaHCO3 ) 1:1.5:1.5:1.5), may

4778 J . Org. Chem., Vol. 64, No. 13, 1999
Long and Chen
Ta ble 3. Rea ction of RF Cl w ith Alk yn es in DMSOa
Sch em e 9
entry
RFClb
alkyne
T °C
time
Z/Ec
yield %d
1
2
3
4
5
6
7
8
9
10
11
12
13
1b
10a
10c
10d
10a
10c
10d
10a
10b
10c
10a
10c
10d
10e
75
80
75
75
75
75
90
90
70
75
70
75
75
8
7
8
8
8
10
10
10
10
10
10
10
10
60/40
92/8
72
71
65
72
69
76
47
52
58
59
64
45
68
Ta ble 4. Solven ts Ar e Tested in th e Rea ction of 1a a n d
15/85
53/47
82/18
15/85
70/30
75/25
50/50
55/45
10/90
0/100
38/62
1c w ith 2b a t 75 °C for 5 h a
1c
1d
RFCl alkene
solvent
DMSO
HMPA
HMPA
converted %b 3% RFH%
1a
1a
1c
1c
1c
1a
1a
2b
2b
2b
2b
2b
2b
2b
100
75
60
10
100
0
80
50
25
<10
50
75
1f
1g
DMF
DMSO/H2O(5/1)
CH3CN/H2O(1/1)
CH3OH
48
0
35c
0
0
0
0
a
b
1:2:Na2S2O4:NaHCO3 1:1.5:1.5:1.5. The conversion of RFCl
a
b
1:2:Na2S2O4:NaHCO3 ) 1:1.5:1.5:1.5. The conversion of RFCl
was 100% determined by 19F NMR. c The ratio of Z/E was
was determined by 19F NMR. c The byproduct is H(CF2)6SO2Na.
determined by 19F NMR. The isolated yields based on RFCl.
d
add to the olefin producing the corresponding adduct.27
However, in our case the sodium sulfinate (12), obtained
without isolation in DMSO, can react with alkene at 80
°C for 8-10 h affording the monoadduct. However, the
yield is low because DMSO is a weak oxidant, as
demonstrated in Scheme 9.28
Sch em e 7
5. Stu d y of Solven t Effect. From the results men-
tioned above, it is apparent that, dramatically different
from CH3CN/H2O, DMSO chosen in these reaction seems
essential for the activation of carbon-chlorine bonds of
perfluoroalkyl chlorides. Because, like DMSO, hexa-
methylphosphoramide (HMPA) or dimethylforamide
(DMF)29 are usually considered to be good solvents for
electron transfer (ET) reaction. Thus, these solvents were
employed to study their effect in the course of the
reactions (1a , 1c, and 2b used as an example). The data
are listed in Table 4.
Sch em e 8
The results from Table 4 showed that, as expected,
HMPA or DMF can be also used in this reaction.
However, the conversion and yield of the adduct were
lower as compared with those in DMSO, with the hydride
being the major product. When 20% (v/v) of H2O was used
as a cosolvent in DMSO, the yield was greatly decreased
accompanying a significant amount of sulfinate salt.
Therefore, DMSO seems to be the best solvent for the
reaction.
from inorganic impurities is very difficult because all of
them are soluble in water. An usual treatment with
chlorine gas in ice-cooled water gives the corresponding
sulfonyl chlorides in low yield, sometimes, accompanying
the formation of RFSO3H (see Scheme 8).
It is known that treatment of the sulfinate salt with
an oxidant generates the perfluoroalkyl radical which can
6. In h ibition a n d Mech a n ism Con sid er a tion . Be-
fore the mechanism consideration, some inhibition ex-
periments were carried out. Addition of ET scavenger,
i.e., p-dinitrobenzene (DNB) (20 mol %) or free radical
inhibitor, i.e., hydroquinone (HQ) (20 mol %) to the
reaction mixture of 1c and 2a decreased the conversion
of 1c significantly (from 100% without DNB and HQ to
50% and 33%, respectively) at the same reaction tem-
perature and time (75 °C for 5 h). UV irradiation
accelerated the reaction, e.g., at 75 °C for 1.5 h the
conversion of 1c is 80% under UV while 20% under
laboratory illumination.
Both the inhibition experiments and the formation of
tetrahydrofuran derivatives from the reaction with diallyl
ether indicated that the perfluoroalkyl radical may be
involved in the reaction mechanism. The most likely
explanation of generation of RF• is that RFCl, quite similar
to RFI,17 accepts one electron from radical anion of sulfur
(26) Chen, J .; Hu, C.-M. Chinese J . Chem. 1994, 12, 468. The Z/E
ratios of the addition products in Table 3 are not regular which cannot
be completely understood yet. Generally, when the RF• adds to alkynes,
they will form both Z- and E- radical intermediate V-Z and V-E.
These intermediates can either isomerize or abstract a hydrogen from
the solvent. If the lifetimes of the radical intermediates are lengthened
by stabilizing (or spin-delocalizing) effects of the substituent R, then
these radical intermediates will be able to isomerize and concentration
of the more stable isomer will increase greatly, i.e., the amount of
radical intermediate V-E, hence, 11E- isomer will become predominant.
On the other hand, if the life-spans of V)-Z and V-E are very short,
then the radical intermediates can abstract hydrogen atom before they
have a chance to isomerize, thus leading to a mixture of Z/E isomers
of 11. (see Li, A.-R.; Chen, Q.-Y. Synthesis 1996, 5, 606.). This
rationalization appears plausible for 11gc (RdC6H5, Z/E ) 10/90, entry
11, Table 3) and 11ba (R ) n-C4H9, Z/E ) 60/40, entry 1, Table 3),
because it is known that C6H5 substitute is much more effective spin-
stabilizer than alkyl substitutes (σjj of C6H5 0.47, σjj of alkyl ) 0.15)
(J iang, X.-K.; J i, G.-Z. J . Org. Chem. 1992, 57, 6051.). However, it
cannot explain the big difference of the Z/E ratios between the products
11bc (Z/E ) 92/8) and 11gc (Z/E ) 10/90) (entry 2 and 11, Table 3)
which were produced from same alkyne (10) but different RFCl (1b
versus 1g). Therefore, besides R, the â- substituent RF in vinyl radicals,
V-Z and V-E, seemingly, has also some influence on the neighboring
free radical and, hence, exert the steroselectivity of the addition
reaction.
(27) (a) Huang, W.-Y.; Xie, Y. Chin. J . Chem. 1990, 4, 362. (b)
Huang, W.-Y.; Hu, L.-Q.; Xie, Y. Acta Chim. Sin. (Engl. Ed.) 1989, 2,
190.
(28) Huang, S.-L.; Omura, K.; Swern, D. Synthesis 1978, 297.
(29) (a) Meijs, G. F. J . Org. Chem. 1986, 51, 606. (b) Bunnett, J . F.;
Scamehorn, R. G.; Traber, R. P. J . Org. Chem. 1976, 41, 3677.

Activation of Carbon-Chlorine Bonds
J . Org. Chem., Vol. 64, No. 13, 1999 4779
was subjected to column chromatography on silica gel to give
3a c as a colorless oil (1.33 g, yield 80%).
Sch em e 10
1,1,1,2,2,3,3,4,4-Non a flu or od od eca n e (3a c): colorless oil;
1H NMR δ 0.88 (t, J ) 6.5 Hz, 3H), 1.15-1.50 (m, 12H), 1.80-
2.45 (m, 2H); 19F NMR δ 4.2 (s, 3F), 37.7 (t, J ) 10.5 Hz, 2F),
47.5 (s, 2F), 49.0 (s, 2F); Ms m/z (relative intensity) 332 (M+,
1.40), 289 (100), 57 (42.53), 43 (25.41); HRMS calcd for
C
12H17F9 332.1187, found 332.1191.
1,1,1,2,2,3,3,4,4-Non a flu or otr id eca n e (3a d ): colorless oil;
1H NMR δ 0.90 (t, J ) 6.5 Hz, 3H), 1.15-1.55 (m, 14H), 1.80-
2.42 (m, 2H); 19F NMR δ 4.2 (s, 3F), 37.6 (t, J ) 10.0 Hz, 2F),
47.3 (s, 2F), 49.0 (2F); Ms m/z (relative intensity) 345 (M+-1,
3.24), 317 (20.12), 303 (43.34), 289 (25.22), 71 (47.85), 43 (100);
HRMS calcd for C13H18F9 (M+ - 1) 345.1264, found 345.1167.
1,1,2,2,3,3,4,4,4-Non a flu or obu tylcycloh exa n e (3a f): col-
dioxide, produced by decomposition of sodium dithionite,
then dissociates to give RF• and Cl-. The RF. adds either
to alkene to form intermediate A, or to SO2-. to form
1
orless oil; H NMR δ 1.13-2.00 (m, 11H); 19F NMR δ 4.2 (s,
3F), 41.3 (d, J ) 12 Hz, 2F), 44.5 (s, 2F), 49.3 (s, 2F); Ms m/z
(relative intensity) 302 (M+, 1.70), 301 (14.39), 263 (20.47), 83
(100); HRMS calcd for C10H10F9 (M+-1) 301.0638, found
301.0631.
•
sulfinate 12. The addition reaction of RF to alkene is
much faster than that to SO2-•, thus, none of the sulfinate
is accompanied. The intermediate, A, did not abstract
chlorine from RFCl due to the strong carbon-chlorine
bond but easily picked a hydrogen from DMSO to afford
the adduct. Chlorination of the sulfinate 12 gives the
1
1,1,2,2,3,3,4,4-Octa flu or od eca n e (3ba ): colorless oil; H
NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.35 (m, 8H), 1.98-2.60 (m,
2H), 6.02 (tt, J ) 52, 5.6 Hz, 1H); 19F NMR δ 37.5 (t, J ) 10
Hz, 2F), 48.9 (s, 2F), 53.4 (s, 2F), 60.4 (d, J ) 49.3 Hz, 2F); Ms
m/z (relative intensity) 286 (M+, 4.05), 285 (34,69), 257 (12.96),
43 (100); HRMS calcd for C10H14F8 286.0968, found 286.0982.
1,1,2,2,3,3,4,4-Octa flu or od od eca n e (3bc): colorless oil;
1H NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.33 (m, 10H), 1.59 (m,
2H), 2.05 (tt, J ) 18.9, 7.9 Hz, 2H), 6.03 (tt, J ) 52, 5.6 Hz,
1H); 19F NMR δ 37.5 (t, J ) 9.7 Hz, 2F), 48.8 (s, 2F), 53.4 (m,
2F), 60.4 (d, J ) 49.3 Hz, 2F); Ms m/z (relative intensity) 314
(M+, 6.55), 285 (14.58), 57 (81.34), 43 (100); HRMS calcd for
•
corresponding sulfonyl chloride. The RF abstracts hy-
drogen from the solvent producing the byproduct, RFH
(see Scheme 10).
The question arises why the reaction of RFCl can be
induced by DMSO but not by CH3CN/H2O, the latter
being very suitable for sulfinatodehalogenation of RFX
(X ) I, Br) and RFCCl3. The reason is not very clear yet
now. In fact, although Na2S2O4 is sparingly soluble in
DMSO at room temperature, the mixture at 75 °C during
stirring becomes highly dispersive. However, the solvent
polarity, dielectric constant and dipole moment of DMSO
and CH3CN are not different very much [ETDMSO (30)
C
12H18F8 314.1280, found 314.1277.
1,1,2,2,3,3,4,4-Octa flu or otr id eca n e (3bd ): colorless oil;
1H NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.20-1.45 (m, 14H), 1.83-
2.42 (m, 2H), 6.02 (tt, J ) 52, 6 Hz, 1H); 19F NMR δ 37.5 (t, J
) 10.0 Hz, 2F), 48.8 (s, 2F), 53.3 (s, 2F), 60.3 (d, J ) 51.2 Hz,
2F); Ms m/z (relative intensity) 328 (M+, 1.69), 299 (10.44),
285 (44.28), 271 (22.86), 257 (14.98), 57 (100); HRMS calcd
for C13H20F8 328.1437, found 328.1428.
) 46 kcal/mol, ET CH3CN (30) ) 45 kcal/mol; ꢀDMSO (25
3CN
°C) ) 46.7, ꢀCH
(20 °C) ) 37.5; µ (DMSO) ) 13.0 ×
3-(2,2,3,3,4,4,5,5-Oct a flu or op en t yl)-4-m et h ylt et r a h y-
10-30 C m, µ (CH3CN) ) 11.5 × 10-30 C m.].30
1
d r ofu r a n (3be):24b colorless oil; H NMR δ 1.05 (d, J ) 6.5
In conclusion, we have developed a new practical
hydroperfluoroalkylation method of alkenes and alkynes
with ever thought inert perfluoroalkyl chlorides in the
presence of sodium dithionite. In addition, perfluoro-
alkanesulfinates and sulfonyl chlorides can be prepared
directly from available perfluoroalkyl chlorides. DMSO
plays a unique role in these reactions.
Hz, 0.7 × 3H, cis-CH3), 1.12 (d, J ) 6.1 Hz, 0.3 × 3H, trans-
CH3), 1.86-2.66 (m, 4H), 3.30-3.53 (m, 2H), 3.91-4.12 (m,
2H), 6.03 (tt, J ) 52, 5.5 Hz, 1H); 19F NMR δ 36.5 (m, 2F),
48.8 (s, 2F), 53.2 (s, 2F), 60.7 (d, J ) 51.7 Hz, 2F); Ms m/z
(relative intensity) 301 (M++1, 35.23), 299 (19.61), 270 (71.90),
69 (100); HRMS calcd for C10H12F8O 300.0760, found 300.0757.
1,1,2,2,3,3,4,4-Octa flu or obu tylcycloh exa n e (3bf): color-
less oil; 1H NMR δ 1.12-2.20 (m, 11H), 6.03 (tt, J ) 52, 6 Hz,
1H); 19F NMR δ 40.7 (d, J ) 13 Hz, 2F), 45.8 (s, 2F), 53.5 (s,
2F), 60.2 (d, J ) 52 Hz, 2F); Ms m/z (relative intensity) 284
(M+, 0.43), 283 (2.69), 263 (12.47), 113 (12.43), 83 (100); HRMS
calcd for C10H11F8 (M+-1) 283.0733, found 283.0734.
Exp er im en ta l Section
1H NMR and 19F NMR spectra were recorded at 90 or 300
MHz and 282 MHz. Chemical shifts were reported in parts
per million relative to TMS as an internal standard for 1H
NMR and to CF3COOH as an external standard (positive for
upfield shifts) for 19F NMR. The solvent for NMR measurement
was CDCl3 (unless otherwise noted). DMSO were distilled from
CaH2 and other reagents were purified prior to use.
Typ ica l P r oced u r e for th e Rea ction of 1 w ith 2. Under
a nitrogen atmosphere, 1a (1.27 g, 5 mmol), 2c (0.84 g, 7.5
mmol), Na2S2O4 (1.38 g, 7.5 mmol), NaHCO3 (0.63 g, 7.5 mmol)
and DMSO (25 mL) was added to a 50 mL three-necked round-
bottomed flask equipped with stirrer and condenser. The
mixture was then heated to 75 °C for 6 h with stirring. The
conversion of 1a was 100%, determined by 19F NMR. After
cooling, the mixture was poured into ice water (30 mL). The
aqueous layer was extracted three times with ether (3 × 30
mL). The combined extracts were washed with water (3 × 20
mL) and dried over Na2SO4. After removing ether, the residue
1,1,2,2,3,3,4,4,5,5,6,6-Dod eca flu or od od eca n e (3ca ): col-
1
orless oil; H NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.32 (m, 6H),
1.56 (m, 2H), 2.05 ((tt, J ) 18.5, 8.7 Hz, 2H), 6.03 (tt, J ) 52,
5.2 Hz, 1H); 19F NMR δ 37.8 (m, 2F), 45.3 (m, 2F), 47.0 (s,
4F), 53.4 (s, 2F), 60.4 (d, J ) 52.6 Hz, 2F); Ms m/z (relative
intensity) 386 (M+, 1.71), 385 (13.14), 367 (14.58), 43 (100).
Anal. Calcd for C12H14F12: C, 37.32; H, 3.62; F, 59.06. Found
C, 37.23; H, 3.56; F, 58.67.
1,1,2,2,3,3,4,4,5,5,6,6-Dodecaflu or otetr adecan e (3cc): col-
1
orless oil; H NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.33 (m, 10H),
1.57 (m, 2H), 2.05 (tt, J ) 18.6, 8.6 Hz, 2H), 6.03 (tt, J ) 52,
6 Hz, 1H); 19F NMR δ 37.7 (t, J ) 15.6 Hz, 2F), 45.2 (s, 2F),
46.9 (s, 4F), 53.0 (s, 2F), 60.4 (d, J ) 52 Hz, 2F); Ms m/z
(relative intensity) 414 (M+, 1.17), 385 (7.50), 371 (36.99), 57
(93.07), 43 (100); HRMS calcd for C14H18F12 414.1217, found
414.1208. Anal. Calcd for C14H18F12: C, 40.58; H, 4.32; F, 55.07.
Found: C, 40.29; H, 4.22; F, 55.59.
1,1,2,2,3,3,4,4,5,5,6,6-Dod eca flu or op en ta d eca n e (3cd ):
colorless oil; 1H NMR δ 0.89 (t, J ) 6.5 Hz, 3H), 1.30 (m, 12H),
1.57 (m, 2H), 2.05 (tt, J ) 18.4, 7.8 Hz, 2H), 6.03 (tt, J ) 52,
5.2 Hz, 1H); 19F NMR δ 37.8 (t, J ) 15.2 Hz, 2F), 45.2 (s, 2F),
(30) Reichardt, C. Solvent Effects in Organic Chemistry; Ebel, H.
F., Ed.; MonographssModern Chemistry; New York: Verlag Chemie,
New York, 1979; p 270.

4780 J . Org. Chem., Vol. 64, No. 13, 1999
Long and Chen
46.9 (s, 4F), 53.1 (s, 2F), 60.1 (d, J ) 52.1 Hz, 2F); Ms m/z
(relative intensity) 428 (M+, 4.76), 399 (38.89), 385 (29.84), 43
(100); HRMS calcd for C15H20F12 428.1372, found 428.1370.
3-(2,2,3,3,4,4,5,5,6,6,7,7-D o d e c a flu o r o h e p t y l)-4-
CH3CO2CH2CH2CH2CF 2CO2Et (3gg): colorless oil; 1H
NMR δ 1.34 (t, J ) 7.1 Hz, 3H), 1.80 (m, 2H), 1.99 (s, 3H),
2.10-2.30 (m, 2H), 4.08 (t, J ) 6.2 Hz, 2H), 4.32 (q, J ) 7.1
Hz, 2H); 19F NMR δ 29.3 (t, J ) 17.2 Hz, 2F); Ms m/z (relative
intensity) 225 (M++1, 8.20), 165 (100), 137 (19.67), 116 (8.64);
HRMS calcd for C9H15O4F2 (M++1) 225.0938, found 225.0933.
Eth yl 2,2-Diflu or o-4-(tr im eth ylsilyl)bu ta n oa te (3gh ):
colorless oil; 1H NMR δ 0.02 (s, 9H), 0.65 (m, 2H), 1.32 (t, J )
7.2 Hz, 3H), 1.80-2.40 (m, 2H), 4.32 (q, J ) 7.1 Hz, 2H); 19F
NMR δ 29.2 (t, J ) 17 Hz, 2F); Ms m/z (relative intensity) 224
(M+, 0.7), 196 (20.70), 101 (12.64), 73 (100); HRMS calcd for
C7H14F2O2Si (M+-C2H4) 196.0732, found 196.0732.
1
m eth yltetr a h yd r ofu r a n (3ce): colorless oil; H NMR δ 1.05
(d, J ) 6.5 Hz, 0.7 × 3H, cis-CH3), 1.12 (d, J ) 6.1 Hz, 0.3 ×
3H, trans-CH3), 1.80-2.50 (m, 4H), 3.18-3.52 (m, 2H), 3.90-
4.10 (m, 2H), 6.03 (tt, J ) 52, 5.5 Hz, 1H); 19F NMR δ 36.3 (m,
2F), 45.0 (s, 2F), 46.4 (s, 4F), 52.6 (s, 2F), 60.5 (d, J ) 52 Hz,
2F); Ms m/z (relative intensity) 401 (M++1, 100), 399 (48.28),
383 (44.78), 370 (27.39), 55 (63.37); HRMS calcd for C12H12F12
400.0707, found 400.0696.
O
Eth yl 2-Ch lor oocta n oa te (3h a ): colorless oil; 1H NMR δ
0.90 (t, J ) 7 Hz, 3H), 1.18-1.70 (m, 11H), 2.10-2.35 (m, 2H),
4.18 (q, J ) 6.5 Hz, 2H), 4.52 (t, J ) 6.5 Hz, 1H); Ms m/z
(relative intensity) 207 (M++1, 7.26), 171 (8.17), 127 (100), 94
(36.56); HRMS calcd for C10H19O2 (M+-Cl) 171.1385, found
171.1376.
1,1,2,2,3,3,4,4,5,5,6,6-Dod eca flu or oh exylcycloh exa n e
1
(3cf): colorless oil; H NMR δ 1.15-2.20 (m, 11H), 6.02 (tt, J
) 52, 6 Hz, 1H); 19F NMR δ 41.2 (d, J ) 13 Hz, 2F), 43.7 (s,
2F), 45.1 (s, 2F), 46.5(s, 2F), 52.8 (s, 2F), 60.2 (d, J ) 52 Hz,
2F); Ms m/z (relative intensity) 383 (M+-1, 1.08), 345 (12.59),
131 (16.56), 83 (100)). Anal. Calcd for C12H12F12 C, 37.50; H,
3.15; F, 59.65. Found: C, 37.68; H, 3.11; F, 60.14.
Eth yl 2-Ch lor od eca n oa te (3h c): colorless oil; 1H NMR δ
0.90 (t, J ) 7 Hz, 3H), 1.05-1.80 (m, 15H), 2.10-2.30 (m, 2H),
4.18 (q, J ) 6.5 Hz, 2H), 4.46 (t, J ) 6.5 Hz, 1H); Ms m/z
(relative intensity) 237 (M++1, 37Cl, 5.69), 235 (M++1, 35Cl,
17.11), 199 (8.60), 191 (18.30), 122 (100); HRMS calcd for
1,1.1-Tr iflu or oocta n e (3d a ):21 colorless oil; 1H NMR δ 0.90
(t, J ) 6.5 Hz, 3H), 1.21-1.50 (m, 10H), 1.90-2.20 (m, 2H);
19F NMR δ -11.2 (t, J ) 10 Hz, 3F).
1,1,1-Tr iflu or od eca n e (3d c):21 colorless oil; 1H NMR δ 0.90
(t, J ) 6.5 Hz, 3H), 1.28-1.70 (m, 14H), 1.98-2.28 (m, 2H);
19F NMR δ -11.0 (t, J ) 10 Hz, 3F).
C
12H23ClO2 (M+, 35Cl) 234.1387, found 234.1415.
Eth yl 2-Ch lor o-2-cycloh exyl a ceta te (3h f): colorless oil;
1H NMR δ 1.20-2.28 (m, 14H), 4.16 (q, J ) 6.5 Hz, 2H), 4.45
(d, J ) 6.5 Hz, 1H); Ms m/z (relative intensity) 205 (M++1,
6.72), 169 (22.37), 122 (100); HRMS calcd for C10H17ClO2 (M+,
35Cl) 204.0917, found 204.0942.
1-Ch lor o-1,1-d iflu or on on a n e (3ec): colorless oil; 1H NMR
δ 0.89 (t, J ) 6.5 Hz, 3H), 1.08-1.50 (m, 12H), 1.97-2.25 (m,
2H); 19F NMR δ -26.8 (t, J ) 13 Hz, 2F); Ms m/z (relative
intensity) 198 (M+, 1.00), 162 (7.56), 105 (15.64), 43 (100);
HRMS calcd for C9H16F2Cl (M+-1) 197.0908, found 197.0938.
Eth yl 2-F lu or od eca n oa te (3fc):25a colorless oil;1H NMR
δ 0.88 (t, J ) 7.0 Hz, 3H), 1.18-1.56 (m, 15H), 1.85 (m, 2H),
4.26 (q, J ) 7.2 Hz, 2H), 4.86 (m, 1H); 19F NMR δ 115.4 (dt, J
) 49.0, 24.5 Hz, 1F).
CH3COO(CH2)4CO2Et (3ig): colorless oil; 1H NMR δ 1.12-
1.40 (m, 5H), 1.62 (m, 2H), 1.85-2.50 (m, 5H), 4.08 (m, 4H);
Ms m/z (relative intensity) 189 (M++1, 2.39), 145 (6.98), 128
(38.38), 101 (100); HRMS calcd for C9H16O4 188.1049, found
188.1050.
1
Eth yl 2-F lu or ou n d eca n oa te (3fd ): colorless oil; 1H NMR
δ 0.89 (t, J ) 6.5 Hz, 3H), 1.01-1.35 (m, 17H), 1.58-1.90 (m,
1,1-Dich lor oh ep ta n e (3ja ): colorless oil; H NMR δ 0.90
(t, J ) 7 Hz, 3H), 1.20-1.65 (m, 8H), 2.14 (m, 2H), 5.72 (t, J
) 6.0 Hz, 1H); Ms m/z (relative intensity) 168 (M+, 0.37), 133
2H), 4.14 (q, J ) 7.2 Hz, 2H), 4.86 (dt, J ) 50, 6.5 Hz, 1H); 19
F
(8.93), 97 (29.60), 83 (10.82), 70 (100); HRMS calcd for C7H14
-
NMR δ 115.4 (dt, J ) 49.6, 24 Hz, 1F); Ms m/z (relative
intensity) 233 (M++1, 66.86), 186 (9.16), 171 (29.35), 127
(10.72), 106 (100); HRMS calcd for C13H25FO2 232.1838, found
232.1840.
Cl2 (M+, 35Cl) 168.0673, found 168.0645.
1
1,1-Dich lor on on a n e (3jc): colorless oil; H NMR δ 0.87
(t, J ) 7 Hz, 3H), 1.13-1.64 (m, 12H), 2.10 (m, 2H), 5.68 (t, J
) 6.0 Hz, 1H); Ms m/z (relative intensity) 196 (M+, 2.50), 139
Eth yl 2-Cycloh exyl-2-flu or oa ceta te (3ff):25a colorless oil;
1H NMR δ 1.12-2.00 (m, 14H), 4.18 (q, J ) 7.1 Hz, 2H), 4.88
(dd, J ) 49.3, 4.3 Hz, 1H); 19F NMR δ 121.0 (dd, J ) 49.3, 22
Hz, 1F).
(7.16), 104 (19.77), 83 (41.63), 43 (100); HRMS calcd for C9H18
-
Cl2 (M+, 35Cl) 196.0785, found 196.0772.
3-(2,2-Dich lor oet h yl)-4-m et h ylt et r a h yd r ofu r a n (3je):
colorless oil; 1H NMR δ 0.95 (d, J ) 6.3 Hz, 0.8 × 3H, cis-
CH3), 1.04 (d, J ) 6.6 Hz, 0.2 × 3H, trans-CH3), 1.88-2.21
(m, 2H), 2.30-2.48 (m, 2H), 3.45 (m, 2H), 3.92 (m, 2H), 5.70
(t, J ) 6.0 Hz, 1H); Ms m/z (relative intensity) 183 (M++1,
7.80), 182 (M+, 6.50), 81 (39.17), 69 (100); HRMS calcd for
C7H12Cl2O (M+, 35Cl) 182.0265, found 182.0237. Anal. Calcd
for C7H12Cl2O: C, 45.92; H, 6.61. Found: C, 45.90; H, 6.73.
4,4-Dich lor obu tyl a ceta te (3jg): colorless oil; 1H NMR δ
1.88 (m, 2H), 2.05 (s, 3H), 2.27 (m, 2H), 4.10 (q, J ) 6.0 Hz,
2H), 5.77 (t, J ) 6.0 Hz, 1H); Ms m/z (relative intensity) 187
(M++1, 37Cl, 7.24), 185 (M++1, 35Cl, 11.48), 124 (15.02), 88
(33.43), 43 (100); HRMS calcd for C4H6Cl2 (M+-CH3CO2H,
35Cl) 123.9847, found 123.9847.
4,4-Dich lor o-1-bu ta n ol (3jj): colorless oil; 1H NMR δ 1.76
(m, 2H), 2.28 (m, 2H), 2.84 (s, 1H), 3.66 (t, J ) 6.2 Hz, 2H),
5.80 (t, J ) 6.0 Hz, 1H); Ms m/z (relative intensity) 143 (M++1,
0.35), 125 (2.90), 96 (11.50), 76 (100); HRMS calcd for C4H8-
Cl2O (M+, 35Cl) 141.9952, found 141.9941. Anal. calcd for C4H8-
Cl2O C, 33.58; H, 5.60. Found: C, 33.89; H, 5.65.
1,2-Dich lor o-1,1,2-tr iflu or oocta n e (3k a ):31 colorless oil;
1H NMR δ 0.90 (t, J ) 7.1 Hz, 3H), 1.20-1.85 (m, 8H), 2.10-
2.59 (m, 2H); 19F NMR δ -10.4 (s, 2F), 43.0 (m, 1F).
Eth yl 2-F lu or o-4-(tr im eth ylsilyl)bu ta n oa te (3fh ):25a col-
orless oil;1H NMR δ 0.00 (s, 9H), 0.60 (m, 2H), 1.28 (t, J ) 7.1
Hz, 3H), 1.87 (m, 2H), 4.25 (q, J ) 7.1 Hz, 2H), 4.80 (ddd, J )
49.4, 6.4, 4.9 Hz, 1H); 19F NMR δ 115.5 (dt, J ) 49.8, 24 Hz,
1F).
Eth yl 5-Eth oxyl-2-flu or op en ta n oa te (3fi):25a colorless
oil;1H NMR δ 1.20 (t, J ) 7.1 Hz, 3H), 1.31 (t, J ) 7.1 Hz,
3H), 1.75 (m, 2H), 1.85-2.10 (m, 2H), 3.45 (m, 4H), 4.26 (q, J
) 7.1 Hz, 2H), 4.94 (ddd, J ) 50.0, 7.6, 4.3 Hz, 1H); 19F NMR
δ 115.2 (dt, J ) 50.2, 24 Hz, 1F).
Eth yl 2,2-Diflu or on on a n oa te (3gb):25d colorless oil; 1H
NMR δ 0.90 (t, J ) 7 Hz, 3H), 1.15-1.48 (m, 13H), 1.90-2.15
(m, 2H), 4.27 (q, J ) 7.1 Hz, 2H); 19F NMR δ 28.7 (t, J ) 17
Hz, 2F).
Eth yl 2,2-Diflu or od eca n oa te (3gc):25d colorless oil; 1H
NMR δ 0.90 (t, J ) 7 Hz, 3H), 1.12-1.48 (m, 15H), 1.90-2.25
(m, 2H), 4.26 (q, J ) 7.1 Hz, 2H); 19F NMR δ 28.7 (t, J ) 17
Hz, 2F).
E t h yl 2,2-Diflu or o-3-(4-m et h ylt et r h yd r ofu r a n -3-yl)-
1
p r op ion a te (3ge): colorless oil; H NMR δ 0.92 (d, J ) 7.0
Hz, 0.75 × 3H, cis-CH3), 1.03 (d, J ) 6.2 Hz, 0.25 × 3H, trans-
CH3), 1.34 (t, J ) 7.2 Hz, 3H), 1.80-2.05 (m, 2H), 2.10-2.55
(m, 2H), 3.45-3.49 (m, 2H), 3.86-4.06 (m, 2H), 4.31 (q, J )
7.1 Hz, 2H); 19F NMR δ 26.8-30.0 (m, 2F); Ms m/z (relative
intensity) 223 (M++1, 100), 193 (17.16), 177 (11.22), 99 (13.87);
HRMS calcd for C10H16F2O3 222.1068, found 222.1068.
Eth yl 2,2-Diflu or o-2-cycloh exyl a ceta te (3gf):25d color-
less oil; 1H NMR δ 1.03-2.05 (m, 14H), 4.33 (q, J ) 7 Hz, 2H);
19F NMR δ 36.5 (d, J ) 15 Hz, 2F).
3-(2,3-Dich lor o-2,3,3-tr iflu or op r op yl)-4-m eth ytetr a h y-
d r ofu r a n (3k e):31 colorless oil; 1H NMR δ 1.02 (d, J ) 6.5
Hz, 0.5 × 3H, cis-CH3), 1.13 (d, J ) 6.1 Hz, 0.5 × 3H, trans-
CH3), 1.80-2.52 (m, 4H), 3.20-3.55 (m, 2H), 3.75-4.08 (m,
2H); 19F NMR δ -10.0 (s, 2F), 41.5 (m, 0.5F), 43.2 (m, 0.5F).
(31) Hu, C.-M.; Qing, F.-L. Tetrahydron Lett. 1990, 31, 1307.

Activation of Carbon-Chlorine Bonds
J . Org. Chem., Vol. 64, No. 13, 1999 4781
1,2-Dich lor o-1,2,2-tr iflu or oeth ylcycloh exan e (3kf):31 col-
2F), 60.5 (d, J ) 51.9 Hz, 2F); Ms m/z (relative intensity) 384
(M+, 0.89), 344 (9.71), 322 (7.18), 121 (38.05), 68 (100); HRMS
calcd for C12H12F12 384.0747, found 384.0748.
1
orless oil; H NMR δ 1.00-2.52 (m, 11H); 19F NMR δ -15.8
(s, 2F), 39.5 (m, 1F).
4,5-Dich lor o-4,5,5-tr iflu or op en tyl a ceta te (3k g):31 color-
H(CF 2)6CHdCHC6H5 (11cc): colorless oil; 1H NMR δ
5.35-6.95 (m, 3H), 7.27 (m, 5H); 19F NMR δ 29.3 (d, J ) 13
Hz, 0.82 × 2F, Z-CF2CH), 34.0 (d, J ) 12 Hz, 0.18 × 2F, E-CF2-
CH), 44.8 (s, 2F), 46.9 (s, 4F), 53.2 (s, 2F), 60.4 (d, J ) 51.0
Hz, 2F); Ms m/z (relative intensity) 404 (M+, 14.32), 403 (100),
384 (12.38), 153 (11.96); HRMS calcd for C14H8F12 404.0434,
found 404.0438. Anal. Calcd for C14H8F12: C, 41.60; H, 2.00;
F, 56.40. Found: C, 41.47; H, 1.96; F, 56.52.
1
less oil; H NMR δ 2.00 (s, 3H), 2.15-2.60 (m, 4H), 4.10 (t, J
) 6.0 Hz, 2H); 19F NMR δ -10.3 (s, 2F), 42.8 (m, 1F).
7,7,8,8,9,9,10,10-Octa flu or oh exa d eca n e (6a ): colorless
1
oil; H NMR δ 0.89 (m, 6H), 1.17-1.50 (m, 16H), 1.75-2.20
(m, 4H); 19F NMR δ 37.5 (m, 4F), 46.7 (s, 4F); Ms m/z (relative
intensity) 370 (M+, 1.55), 369 (9.09), 135 (25.24), 57 (72.20),
43 (100); HRMS calcd for C16H26F8 370.1970, found 370.1968.
7,7,8,8,9,9,10,10-Octa flu or oeicosa n e (6c): colorless oil;
1H NMR δ 0.89 (m, 6H), 1.20-1.52 (m, 24H), 1.78-2.23 (m,
4H); 19F NMR δ 37.3 (m, 4F), 46.4 (s, 4F); Ms m/z (relative
intensity) 426 (M+, 0.87), 383 (2.58), 85 (35.93), 71 (56.06), 57
(100); HRMS calcd for C20H34F8 426.2533, found 426.2536.
7,7,8,8-Tetr a flu or o-8-ch lor o-2-octa n on e (8): colorless
oil; 1H NMR δ 1.55-1.80 (m, 4H), 2.15 (s, 3H), 2.30-2.65 (m,
4H); 19F NMR δ -6.6 (s, 2F), 36.8 (m, 2F); Ms m/z (relative
intensity) 237 (M++1, 37Cl, 15.64), 235 (M++1, 35Cl, 46.25), 135
(25.24), 43 (100). Anal. Calcd for C8H11F4ClO: C, 40.95; H,
4.73; F, 32.39. Found: C, 40.74; H, 4.71; F, 32.28.
1
H(CF 2)6CHdCHCH2OH (11cd ): colorless oil; H NMR δ
(CD3COCD3) 3.45 (s, 1H), 4.40-4.30 (m, 2H), 5.70-6.72 (m,
2H), 6.82 (tt, J ) 50.9, 5.3 Hz, 1H); 19F NMR δ (CD3COCD3)
25.7 (d, J ) 12.6 Hz, 0.15 × 2F, Z-CF2CH), 29.4 (d, J ) 11.9
Hz, 0.85 × 2F, E-CF2CH), 40.2 (s, 2F), 42.1 (s, 4F), 48.3 (s,
2F), 57.2 (d, J ) 50.7 Hz, 2F); Ms m/z (relative intensity) 357
(M+-1, 2.12), 340 (15.56), 290 (18.86), 139 (40.63), 57 (100).
Anal. Calcd for C9H6F12O: C, 30.18; H, 1.68; F, 63.65. Found:
C, 30.24; H, 1.87; F, 63.22.
CF 3CH2CHdCHC4H9 (11d a ):22 colorless oil; 1H NMR δ 0.89
(t, J ) 7.1 Hz, 3H), 1.24 (m, 4H), 1.94 (m, 2H), 2.65 (m, 2H),
5.40-6.30 (m, 2H); 19F NMR δ -11.6 (t, J ) 11.0 Hz, 0.7 ×
3F, Z-), -10.6 (t, J ) 10.9 Hz, 0.3 × 3F, E-); Ms m/z (relative
intensity) 166 (M+, 28.03), 119 (100), 117 (85.75), 69 (18.95);
HRMS calcd for C8H13F3 166.0969, found 166.0965.
7,7,8,8-Tetr a flu or o-2-tetr a d eca n on e (9a ): colorless oil;
1H NMR δ 0.89 (t, J ) 7 Hz, 3H), 1.25-1.58 (m, 12H), 1.85-
2.40 (m, 7H), 2.68 (t, J ) 7 Hz, 2H); 19F NMR δ 38.2 (m, 4F);
Ms m/z (relative intensity) 285 (M++1, 100), 264 (2.64), 58
(79.80), 43 (69.22); HRMS calcd for C14H24F4O 284.1763, found
284.1769.
CF 3CH2CHdCHC6H13 (11d b):22 colorless oil;1H NMR δ
0.88 (t, J ) 7.1 Hz, 3H), 1.27 (m, 8H), 1.98 (m, 2H), 2.67 (m,
2H), 5.45-6.43 (m, 2H); 19F NMR δ -11.4 (t, J ) 11.0 Hz,
0.75 × 3F, Z-), -10.2 (t, J ) 10 Hz, 0.25 × 3F, E-); Ms m/z
(relative intensity) 194 (M+, 40.70), 151 (28.88), 69 (72.98), 43
(100); HRMS calcd for C10H17F12: 194.1283, found: 194.1291.
7,7,8,8-Tetr a flu or o-2-h exa d eca n on e (9c): colorless oil;
1H NMR δ 0.89 (t, J ) 7 Hz, 3H), 1.22-1.57 (m, 16H), 1.86-
2.41 (m, 7H), 2.74 (t, J ) 7 Hz, 2H); 19F NMR δ 38.3 (m, 4F);
Ms m/z (relative intensity) 313 (M++1, 64.03), 311 (6.31), 58
1
(77.24), 43 (100); HRMS calcd for
found: 312.2065.
C
16H28F4O: 312.2076,
C6H5CHdCHCF HCO2Et (11fc): colorless oil; H NMR δ
1.32 (t, J ) 7.2 Hz, 3H), 4.30 (q, J ) 7.2 Hz, 2H), 5.40-6.35
(m, 2H), 6.85-7.05 (m, 1H), 7.40 (m, 5H); 19F NMR δ 97.8 (ddd,
J ) 48.0, 10.9, 4.0 Hz, 0.5F, Z-), 106.7 (dd, J ) 48.0, 11.0 Hz,
0.5F, E-); Ms m/z (relative intensity) 209 (M++1, 2.21), 208
Typ ica l P r oced u r e for th e Rea ction of 1 w ith 10. Under
a nitrogen atmosphere, into a 50 mL three-necked round-
bottomed flask, equipped with magnetic stirrer, thermometer,
and condenser, was added the mixture of 1b (1.18 g, 5 mmol),
10a (0.63 g, 7.5 mmol), Na2S2O4 (1.38 g, 7.5 mmol), NaHCO3
(0.63 g, 7.5 mmol), and DMSO (25 mL). The mixture was then
heated to 75 °C for 8 h with stirring. The conversion of 1a
was 100%, determined by 19F NMR. After cooling, the mixture
was poured into ice water (30 mL). The aqueous layer was
extracted three times with ether (3 × 30 mL). The combined
extracts were washed with water (3 × 20 mL) and dried over
Na2SO4. After removing ether, the residue was subjected to
column chromatography on silica gel to afford 11ba as a
colorless oil (1.02 g, yield 72%).
(M+, 16.49), 135 (100), 115 (73.29); HRMS calcd for C12H13
FO2 208.0899, found 208.0889.
-
C4H9CHdCHCF 2CO2Et (11ga ): colorless oil; 1H NMR δ
0.90 (t, J ) 7.2 Hz, 3H), 1.27-1.47 (m, 7H), 2.20-2.32 (m, 2H),
4.30 (q, J ) 7.2 Hz, 2H), 5.51-6.30 (m, 2H); 19F NMR δ 21.8
(d, J ) 13.7 Hz, 0.55 × 2F, Z-), 26.0 (dd, J ) 10.8, 4.5 Hz, 0.45
× 2F, E-); Ms m/z (relative intensity) 207 (M++1, 2.02), 206
M+, 2.73), 186 (5.20), 113 (100), 77 (99.99); HRMS calcd for
C
C
10H16F2O2: 206.1118, found: 206.1116. Anal. Calcd for
10H16F2O2: C, 58.24; H, 7.82; F, 18.42. Found: C, 58.17; H,
7.70; F, 17.97.
H(CF 2)4CHdCHC4H9 (11ba ): colorless oil; 1H NMR δ 0.92
(t, J ) 7.0 Hz, 3H), 1.22-1.60 (m, 4H), 2.30-2.33 (m, 2H),
5.37-6.55 (m, 2H), 6.02 (tt, J ) 52, 5.2 Hz, 1H); 19F NMR δ
29.7 (d, J ) 9.6 Hz, 0.6 × 2F, Z-), 34.2 (d, J ) 10.5 Hz, 0.4 ×
2F, E-), 48.6 (s, 2F), 53.0 (s, 2F), 60.5 (d, J ) 52 Hz, 2F); Ms
m/z (relative intensity) 284 (M+, 8.96), 264 (12.20), 222 (12.75),
68 (100); HRMS calcd for C10H12F8 284.0811, found 284.0805.
H(CF 2)4CHdCHC6H5 (11bc): colorless oil; 1H NMR δ
5.52-6.96 (m, 3H), 7.20 (m, 5H); 19F NMR δ 28.3 (d, J ) 10.0
Hz, 0.92 × 2F, Z-), 33.9 (d, J ) 11 Hz, 0.08 × 2F, E-), 48.3 (s,
2F), 53.0 (s, 2F), 60.3 (d, J ) 51.0 Hz, 2F); Ms m/z (relative
intensity) 304 (M+, 36.87), 153 (100), 133 (62.84); HRMS calcd
for C12H8F8 304.0498, found 304.0493.
E-C6H5CHdCHCF 2CO2Et (11gc): colorless oil; 1H NMR
δ (CD3COCD3): 1.08 (t, J ) 7.2 Hz, 3H), 4.06 (q, J ) 7.2 Hz,
2H), 5.92 (dt, J ) 14.6, 12.7 Hz, 1H), 7.04 (dt, J ) 14.6, 1.8
Hz, 1H), 7.36 (m, 5H); 19F NMR δ (CD3COCD3): 11.5 (d, J )
13 Hz, 2F); Ms m/z (relative intensity) 227 (M++1, 1.34), 226
(M+, 9.14), 153 (100), 133 (67.75); HRMS calcd for C12H12F2O2
226.0805, found 226.0807.
E-HOCH2CHdCHCF2CO2Et (11gd): colorless oil; 1H NMR
δ 1.30 (t, J ) 7.2 Hz, 3H), 3.23 (s, 1H), 4.21 (dd, J ) 4.2, 2.0
Hz, 2H), 4.29 (q, J ) 7.2 Hz, 2H), 5.95 (dtt, J ) 15.8, 11.3, 2.0
Hz, 1H), 6.42 (dtt, J ) 15.8, 4.1, 2.5 Hz, 1H); 19F NMR δ 26.4
(dd, J ) 10.6, 3.9 Hz, 2F); Ms m/z (relative intensity) 181-
(M++1, 14.04), 163 (84.06), 135 (100), 107 (53.34), 90 (74.74);
HRMS calcd for C7H10F2O3 180.0598, found 180.0581.
CH3OCH2CHdCHCF2CO2Et (11ge): colorless oil; 1H NMR
δ 1.35 (t, J ) 7.2 Hz, 3H), 3.30 (s, 0.38 × 3H, Z-CH3O), 3.37(s,
0.62 × 3H, E-CH3O), 4.05 (dq, J ) 7.7, 2.0 Hz, 0.62 × 2H,
E-CH2CHdCH), 4.20 (dq, J ) 7.6, 2.2 Hz, 0.38 × 2H, Z-CH2-
CHdCH), 4.35 (q, J ) 7.2 Hz, 2H), 5.56-6.36 (m, 2H); 19F
NMR δ 22.8 (d, J ) 15.9 Hz, 0.38 × 2F, Z-), 27.0 (dd, J )
11.0, 4.1 Hz, 0.62 × 2F, E-); Ms m/z (relative intensity) 195-
(M++1, 1.86), 174 (91.06), 163 (10.60), 121 (100), 90 (69.49).
Anal. Calcd for C8H12F2O3: C, 49.48; H, 6.23; F, 19.57.
Found: C, 49.74; H, 6.40; F, 19.63.
1
H(CF 2)4CHdCHCH2OH (11bd ): colorless oil; H NMR δ
2.50 (s, 1H), 4.32 (dd, J ) 6.1, 3.6 Hz, 0.85 × 2H, E-CH2O),
4.44 (dt, J ) 7.9, 3.5 Hz, 0.15 × 2H, Z-CH2O), 5.47-6.58 (m,
2H), 6.05 (tt, J ) 52, 5.6 Hz, 1H); 19F NMR δ 30.9 (s, 0.15 ×
2F, Z-CF2CH), 34.9 (d, J ) 8.1 Hz, 0.85 × 2F, E-CF2CH), 48.7
(t, J ) 7.8 Hz, 0.85 × 2F), 49.0 (t, J ) 7.0 Hz, 0.15 × 2F), 53.0
(d, J ) 4.3 Hz, 2F), 60.5 (d, J ) 51.8 Hz, 2F); Ms m/z (relative
intensity) 258 (M+, 0.30), 241 (8.71), 221 (3.64), 57 (100);
HRMS calcd for C7H5F8O (M+-1) 257.0213, found 257.0192.
H(CF 2)6CHdCHC4H9 (11ca ): colorless oil; 1H NMR δ 0.92
(t, J ) 7.0 Hz, 3H), 1.24-1.60 (m, 4H), 2.30-2.33 (m, 2H),
5.43-6.39 (m, 2H), 6.04 (tt, J ) 52, 6 Hz, 1H); 19F NMR δ
30.0 (d, J ) 11.9 Hz, 0.53 × 2F, Z-CF2CH), 34.6 (d, J ) 11.9
Hz, 0.47 × 2F, E-CF2CH), 45.1 (s, 2F), 47.0 (m, 4F), 53.2 (s,
Typ ica l P r oced u r e for P r ep a r a tion of 12 a n d 13. An
amount of 1a (2.55 g, 10 mmol), Na2S2O4 (2.61 g, 15 mmol),
NaHCO3 (1.26 g, 15 mmol) and DMSO (30 mL) was stirred at

4782 J . Org. Chem., Vol. 64, No. 13, 1999
Long and Chen
75 °C for 10 h. After removal of solvent under reduced
pressure, the residure was extracted with hot ethanol. Evapo-
ration of the ethanol gave the sodium salt 12a . Chlorine gas
was bubbled into a solution of 12a in H2O (10 mL) at 0 °C for
4 h. The mixture was extracted three times with CH2Cl2 (3 ×
10 mL). The oil layer separated was dried over anhydrous
MgS2O4. After removing the solvent, 13a (1.27 g, 40%) was
obtained.
7.5 mmol), NaHCO3 (0.63 g, 7.5 mmol), and DMSO (25 mL)
was added to a three-necked round-bottomed flask. After the
mixture was stirred for 5 h at 75 °C under the laboratory light,
19F NMR analysis, i.e., intergration ratio of peaks at -8.0 ppm
(RFCF 2Cl) and 37.7 ppm (RFCF 2CH2CH2R), indicated that the
conversion of 1c was 100%. When p-DNB (0.17 g, 1 mmol) was
present, after the mixture was stirred for 5 h at 75 °C, 19F
NMR analysis showed 50% conversion of 1c.
CF 3(CF 2)3SO2Na (12a ):17d white solid; 19F NMR δ (D2O) 4.3
(s, 3F), 46.5 (s, 2F), 48.5 (s, F), 53.1 (s, 2F, CF2SO2Na).
H(CF 2)4SO2Na (12b):17e white solid; 19F NMR δ (D2O) 47.2
(s, 2F), 52.6 (s, 2F), 53.3 (s, 2F, CF2SO2Na), 61.6 (d, J ) 51
Hz, 2F).
Similarly, when HQ (0.11 g, 1 mmol) was present instead
of p-DNB and the reaction conducted for 5 h at 75 °C, 19F NMR
analysis showed 33% conversion of 1c.
CF 3CH2SO2Na (12d ):21 white solid, 19F NMR δ (D2O) -17.6
Ack n ow led gm en t. We thank Professor Huang, W.-
Y. for his encouragement and the Natural Science
Foundation of China for support of this work.
1
(t, J ) 12 Hz, 3F), H NMR δ (D2O) 3.23 (q, J ) 12 Hz, 2H).
CF 3(CF 2)3SO2Cl (13a ):17d colorless oil;19F NMR δ (neat) 4.3
(s, 3F), 27.7 (s, 2F, CF2SO2Cl), 43.1 (s, 2F), 49.0 (s, 2F).
H(CF 2)4SO2Cl (13b):17e colorless oil; 19F NMR δ (neat) 27.7
(s, 2F, CF2SO2Cl), 43.6 (s, 2F), 51.3 (s, 2F), 60.8 (d, J ) 51 Hz,
2F).
Su p p or tin g In for m a tion Ava ila ble: 1H NMR spectra of
3bc, 3be, 3ca , 3cc, 3cd , 3fh , 3fi, 3ge, 3gg, 3jj, 11bd , 11ca ,
11cd , 11ga , 11gd , and 11ge. 19F NMR spectra of 3bc, 3be,
3ca , 3cc, 3cd , 3fh , 3fi, 3gg, 11bd , 11ca , 11cd , 11ga , 11gd ,
and 11ge.
CF 3CH2SO2Cl (13d ):21 colorless oil;19F NMR δ (neat) -15.0
1
(t, J ) 10 Hz, 3F); H NMR δ (neat) 4.37 (q, J ) 9 Hz, 2H).
Typ ica l In h ibition Exp er im en t: Under N2 atmosphere,
1c (1.68 g, 5 mmol), 2a (0.63 g, 7.5 mmol), Na2S2O4 (1.38 g,
J O9900937