Synthesis of β-trifluoroacetyl-substituted vinyl sulfones and vinyl sulfides

Article abstract of DOI:10.1023/A:1021620228529

Oxidation of β-(trifluoroacetyl)vinyl sulfides afforded a series of the corresponding sulfones. The reactions of sulfones with various alkyl- and arylthiols were studied. These reactions provide the basis for a new procedure for the synthesis of β-(trifluoroacetyl)vinyl sulfides.

Full text of DOI:10.1023/A:1021620228529

2080
Russian Chemical Bulletin, International Edition, Vol. 51, No. 11, pp. 2080—2085, November, 2002
Synthesis of βꢀtrifluoroacetylꢀsubstituted vinyl sulfones
and vinyl sulfides
ꢀ
A. L. Krasovsky, V. G. Nenajdenko, and E. S. Balenkova
M. V. Lomonosov Moscow State University, Department of Chemistry,
Leninskie Gory, 119992 Moscow, Russian Federation.
Fax: +7 (095) 932 8846. Eꢀmail: nen@acylium.chem.msu.ru
Oxidation of βꢀ(trifluoroacetyl)vinyl sulfides afforded a series of the corresponding sulꢀ
fones. The reactions of sulfones with various alkylꢀ and arylthiols were studied. These reactions
provide the basis for a new procedure for the synthesis of βꢀ(trifluoroacetyl)vinyl sulfides.
Key words: vinyl sulfides, vinyl sulfones, oxidation, nucleophilic substitution, thiols.
βꢀAcylvinyl sulfones are of considerable theoretical
acetyl)vinyl sulfides 1 and 2 to the corresponding sulꢀ
fones. Previously,16 oxidation of analogous compounds,
viz., βꢀarylꢀβꢀ(methylthio)vinyl trifluoromethyl ketones,
has been performed with the use of hydrogen peroxide in
acetic acid. However, the compounds under considerꢀ
ation were not oxidized under these conditions at room
temperature, whereas an attempt to carry out the reaction
at higher temperature resulted in complete resinification
of the reaction mixture. Because of this, we performed
oxidation of sulfides 1 and 2 with a stronger oxidizer, viz.,
trifluoroperacetic acid, which allows one to carry out oxiꢀ
dation under mild conditions. Oxidation of vinyl sulfides
to sulfones under the action of trifluoroperacetic acid can
be carried out both in dichloromethane18,19 and trifluoroꢀ
acetic acid.20
and practical interest.1,2 This interest stems primarily from
the fact that these compounds are active dienophiles and
can serve as synthetic equivalents of vinyl ketones3—6 and
ethynyl ketones7—12 because the sulfonyl group can readily
be removed from the resulting cycloadducts. In addition,
βꢀacylvinyl sulfones serve as active electrophiles and the
sulfonyl group often acts as a good leaving group.13—15
However, the only example of the synthesis of analogous
fluorinated compounds, viz., βꢀarylꢀβꢀ(methylsulfoꢀ
nyl)vinyl trifluoromethyl ketones, was reported,16 whereas
unsubstituted βꢀ(trifluoroacetyl)vinyl sulfones have not
been prepared at all.
In the present study, we developed a procedure for the
synthesis of βꢀ(trifluoroacetyl)vinyl sulfones and examꢀ
ined their electrophilic properties in reactions with thiols.
We used βꢀ(trifluoroacetyl)vinyl sulfides 1 and 2 as the
starting compounds, which were prepared by trifluoroꢀ
acetylation according to the Hojo method from the correꢀ
sponding readily available phenyl vinyl sulfide and methyl
vinyl sulfide.17 We studied oxidation of βꢀ(trifluoroꢀ
It should be noted that oxidation with trifluoroꢀ
peracetic acid, which was prepared by mixing 50% hydroꢀ
gen peroxide and trifluoroacetic acid (1 equiv./1 equiv.),
afforded the corresponding diols 5 and 6 rather than
the expected βꢀ(trifluoroacetyl)vinyl sulfones 3 and 4
(Scheme 1).
Scheme 1
R = Ph (1, 3, 5), Me (2, 4, 6); E/Z = 7/5 (1), 3/1 (2)
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1925—1930, November, 2002.
1066ꢀ5285/02/5111ꢀ2080 $27.00 © 2002 Plenum Publishing Corporation

Substituted vinyl sulfones and vinyl sulfides
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 11, November, 2002 2081
Table 1. Isomer ratios of ketones 4 and diols 5 and 6 in the
oxidation products of sulfides 1 and 2 in different solvents
Interestingly, the precursors of sulfones, viz., sulfides
1 and 2, exist exclusively as ketones. However, oxidation
of these sulfides to sulfones 5 and 6 led to such an enꢀ
hancement of the electronꢀwithdrawing properties of the
carbonyl group of these compounds that they form stable
gemꢀdiols as white crystalline compounds.
We also carried out oxidation of sulfides 1 and 2 in the
absence of water. Oxidation was performed with the use
of anhydrous trifluoroperacetic acid synthesized from
98% hydrogen peroxide and trifluoroacetic anhydride. The
reaction was performed in anhydrous trifluoroacetic acid
at –20 °C. It is particularly interesting that we obtained
exclusively the Eꢀisomers of ketones 3 and 4 in both reꢀ
actions.
We believe that the need for a strong oxidizer, such as
trifluoroperacetic acid, arises from the low nucleophilicꢀ
ity of the S atom in the starting sulfides 1 and 2 due to the
electronꢀwithdrawing effect of the trifluoroacetyl group.
Actually, our attempt to prepare the corresponding sulfoꢀ
nium salt by methylation of sulfides 1 and 2 under the
action of even such a strong methylating agent as methyl
triflate was unsuccessful (Scheme 2).
Sulfide
Comꢀ
pound
Content (%)
CD3CN
CDCl3
CD3OD
1*
5a
5b
4a
6a
6c
75
25
33
67
—
100
—
—
33
66
100
—
—
100
—
2**
* Compound 3a was not detected.
** Diol 6b was not detected.
3
two pairs of doublets with the constants JH,H = 15.1
and 15.4 Hz, which correspond to transꢀdiol 6a and
transꢀketone 4a, respectively. The 13C NMR spectrum
has a quadruplet at δ 178.6 corresponding to the C atom
of the carbonyl group of ketone 4a and a quadruplet at
δ 93.2 belonging to the C atom of the diol group of molꢀ
1
ecule 6a. The H NMR spectrum recorded in CD3CN
3
shows two pairs of doublets with the constants JH,H
=
15.0 and 15.2 Hz. The 13C NMR spectrum has two quaꢀ
druplets at δ 99.6 and 92.4. We believe that the second set
of signals belongs to hemihydrate 6c (Scheme 3). Comꢀ
pounds containing an analogous fragment have been preꢀ
pared previously21 in our research group and their strucꢀ
tures were unambiguously established by Xꢀray diffracꢀ
tion analysis.
Scheme 2
Scheme 3
The NMR spectroscopic studies of sulfones 5 and 6
showed that the transformations between the dipolar and
ketone forms of the sulfones under consideration as well
as between the E/Z isomers of the diols occur depending
on the nature of the solvent used. The configurations and
ratios of the sulfones obtained were determined based on
the spinꢀspin coupling constants between the protons at
1
the double bond found from the H NMR spectra and
taking into account the characteristic signals for the
C atoms of the carbonyl group (for compounds 3 and 4)
or the gemꢀdiol group (for compounds 5 and 6) in the
13C NMR spectra. Thus, the highest content of Zꢀdiol 5b
was obtained in lowꢀpolarity aprotic solvents (for example,
in CDCl3) due, apparently, to intermolecular hydrogen
bonding resulted from the low solvating ability of these
solvents. In polar solvents, for example, in CD3CN or
CD3OD, Eꢀdiol 5a occurred as virtually the only isomer,
which is attributed both to its higher polarity compared to
5b and the fact that it can be solvated in CD3OD (Table 1).
A somewhat different situation was observed for diol 6
(see Table 1). Thus, the NMR spectra recorded in CDCl3
have signals corresponding to Eꢀketone 4a along with the
signals of Eꢀdiol 6a. The 1H NMR spectrum shows
The assignment of the signals in the spectra was made
based on the comparison of the corresponding signals of

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Russ.Chem.Bull., Int.Ed., Vol. 51, No. 11, November, 2002
Krasovsky et al.
Scheme 6
Eꢀdiol 6a in the spectrum recorded in CDCl3 with those
measured in CD3CN. It should be noted that the spinꢀ
spin coupling constant for the H atoms at the double
bond in Eꢀhemihydrate 6c is intermediate between the
analogous constants for Eꢀdiol 6a and Eꢀketone 4a. The
absence of the hemihydrate form in the case of phenylꢀ
sulfonylꢀsubstituted diol 5a is attributable to the stronger
electronꢀwithdrawing ability of the phenylsulfonyl group
compared to that of the mesyl group. The NMR spectra
in CD3OD, like those of the phenyl analog 5, have signals
corresponding only to the Eꢀisomer of diol 6a.
When studying ketones 3 and 4, we found that they
readily added a water molecule at the carbonyl group to
form diols 5 and 6, respectively, even upon storage in air*
(Scheme 4). The ratios of the E/Z isomers in the diol
forms of 5 and 6 are identical with those obtained from
sulfides 1 and 2.
5a/5b = 3a/3b = 3/1
tyl)vinyl sulfides. We used a number of solvents (CH2Cl2,
H2O, EtOH, and MeCN). It appeared that the highest
yields were achieved in MeCN, the reaction proceeding
readily even with the less reactive diol forms of sulfones 5
and 6. In most cases, the yield of the target product was
virtually independent of which diol (5 or 6) was added
(Scheme 7). The E/Zꢀisomer ratio in the resulting βꢀ(triꢀ
fluoroacetyl)vinyl sulfides 1 and 7—10 is independent of
the E/Zꢀisomer ratio in the starting sulfones 5 and 6 and is
determined, apparently, exclusively by the structure of
the substituent R´.
Scheme 4
Diol 6a can be readily subjected to the reverse transꢀ
formation under the action of thionyl chloride in anhyꢀ
drous CH2Cl2 at room temperature (Scheme 5). This reꢀ
action afforded Eꢀketone 4a as the only product.
Scheme 7
Scheme 5
Compound
R´
E/Z
Yield from different
diols (%)
5
6
1
7
8
9
Ph
Et
7/5
3/2
2/1
7/3
0/1
90
87
89
80
76
86
84
86
82
—
Dehydration of diol 5 proceeded on refluxing over
P2O5 in anhydrous CH2Cl2 (Scheme 6). Interestingly, the
E/Zꢀisomer ratio of ketones 3a/3b is identical with that
for the starting diol 5.
4ꢀMeC6H4
1ꢀNaphthyl
4ꢀNO2C6H4
10
Previously, using the reactions with the Cꢀ, Nꢀnucleoꢀ
philes and dienes as examples, we have demonstrated that
sulfones 5 and 6 belong to a new class of active dienoꢀ
philes22 and electrophiles.23,24 In this connection, in the
present study, we examined also the reactions of sulfones
5 and 6 with Sꢀnucleophiles, viz., thiols. These reactions
will enable one to synthesize various βꢀ(trifluoroaceꢀ
In the case of poorly reactive pꢀnitrothiophenol, diol 5
is the reagent of choice because the reaction with diol 6
proceeded very slowly resulting finally in resinification of
the reaction mixture. It should be emphasized that vinyl
sulfide 10 was produced as the only Z isomer, whereas
sulfides 1 and 7—9 were obtained as mixtures of the E/Z
isomers, which is attributable to the fact that compound 10
has the stronger hypervalent bond between the S atom
and the O atom of the carbonyl group.25
* Hydration did not allow us to obtain reliable data from elꢀ
emental analysis of ketones 3a and 4a.

Substituted vinyl sulfones and vinyl sulfides
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 11, November, 2002 2083
Scheme 9
The reactions of pꢀmethoxythiophenol with diols 5
and 6 also gave interesting results (Scheme 8). The reacꢀ
tion with the use of 1 equiv. of pꢀmethoxythiophenol
afforded a poorly separable mixture of monoꢀ and diꢀ
adducts, whereas the reaction with the use of 2.2 equiv. of
pꢀmethoxythiophenol gave stable diadduct 12 in quantiꢀ
tative yield. Apparently, this fact is attributed to the high
nucleophilicity of pꢀmethoxythiophenol resulting in the
addition of the thiol at the double bond of unsaturated
ketone 11 to form diadduct 12.
R´ = Et (7, 13), 4ꢀMeC6H4 (8, 14), 1ꢀNaphthyl (9, 15)
To summarize, we developed a procedure for the synꢀ
thesis of new promising electroꢀ and dienophiles 3—6. We
investigated the reactions of diols 5 and 6 with different
thiols and devised a new procedure for the synthesis of
βꢀ(trifluoroacetyl)vinyl sulfides. The resulting sulfides
were successfully oxidized to the corresponding sulfones.
Scheme 8
Experimental
The 1H and 13C NMR spectra were recorded on a Varian
VXRꢀ400 spectrometer (400 and 100 MHz, respectively) in
CDCl3 with Me4Si as the internal standard. The IR spectra were
measured on a URꢀ20 spectrometer in Nujol mulls. The TLC
analysis was carried out on Silufol UVꢀ254 plates; visualization
was carried out in an acidified solution of KMnO4 and with
iodine vapor.
Synthesis of phenyl βꢀ(trifluoroacetyl)vinyl sulfone (3a) and
methyl βꢀ(trifluoroacetyl)vinyl sulfone (4a) from the correspondꢀ
ing sulfides 1 and 2. Sulfide 1 or 2 (0.02 mol) was placed in a
roundꢀbottom threeꢀneck flask and cooled to –10 °C. Then
CF3COOH (15 mL) was added and the reaction solution was
cooled to –30 °C. A mixture of 98% H2O2 (0.045 mol) and
(CF3CO)2O (0.05 mol) was slowly added dropwise with vigorꢀ
ous stirring, the temperature being maintained at no higher than
–30 °C. Then the reaction mixture was kept at –30 °C for 3 h
and slowly warmed to ∼20 °C, after which CF3COOH was disꢀ
tilled off in vacuo (10 Torr). The product (oily white crystals)
was dried in vacuo (0.1 Torr).
R´ = 4ꢀMeOC6H4
It should be noted that the main procedure for the
synthesis of unsaturated βꢀ(trifluoroacetyl)vinyl sulfides
involves trifluoroacetylation of the corresponding vinyl
sulfides.17,26,27 Therefore, the development of a proceꢀ
dure for the synthesis of βꢀ(trifluoroacetyl)vinyl sulfides
directly from thiols is an important synthetic problem,
which allows one to circumvent laborious steps of the
preꢀpreparation of vinyl sulfides followed by trifluoroꢀ
acylation. This method made it possible to synthesize for
the first time (pꢀnitrophenylthio)vinyl trifluoromethyl keꢀ
tone (10). Our attempts to perform trifluoroacetylation of
pꢀnitrophenyl vinyl sulfide failed due to the low reactivity
of this substrate.
Therefore, we devised a new oneꢀstep procedure for
the synthesis of βꢀ(trifluoroacetyl)vinyl sulfides from thiꢀ
ols, the thiol molecule remaining intact in the course of
the reaction. The latter fact enables one to perform the
reactions with optically active thiols.
We also studied oxidation of the resulting βꢀ(trifluoroꢀ
acetyl)vinyl sulfides 7—10 to the corresponding sulfones
(Scheme 9). Sulfides 7—9 containing electronꢀdonating
substituents were oxidized to sulfones 13—15 in good
yields. It should be noted that all these sulfones, like
sulfones 5 and 6, occurred in the dipole form. However,
attempts to oxidize electronꢀwithdrawing sulfide 10 both
in aqueous and nonꢀaqueous conditions led to complete
resinification of the reaction mixture.
Sulfone 3a. The yield was 96%, m.p. 74—78 °C. 1H NMR
(CDCl3), δ: 7.75 (m, 2 H, Ph); 7.48 (m, 1 H, Ph); 7.44 (d, 1 H,
C(4)H, J = 15.3 Hz); 7.36 (m, 2 H, Ph); 7.18 (d, 1 H, C(3)H,
J = 15.3 Hz). 13C NMR, δ: 178.5 (C=O); 146.5, 136.8, 134.7,
129.5, 129.2, 126.9, 115.1 (q, CF3, J = 290.0 Hz).
Sulfone 4a. The yield was 97%, m.p. 56—58 °C. The 1H and
13C NMR spectra are given below.
Synthesis of 1,1,1ꢀtrifluoroꢀ4ꢀ(Rꢀsulfonyl)butꢀ3ꢀeneꢀ2,2ꢀdiꢀ
ols 5, 6, and 13—15. The corresponding sulfide 1, 2, or 7—9
(10 mmol) was placed in a roundꢀbottom oneꢀneck flask and
cooled to –20 °C. Then CF3COOH (20 mL) was added. The
reaction mixture was cooled to –30 °C and a mixture of 50%
H2O2 (30 mmol) and CF3COOH (10 mL) was slowly added
dropwise with vigorous stirring. The reaction mixture was kept
at –20 °C for 3 h and slowly warmed to ∼20 °C. Then CF3COOH
was distilled off under weak vacuum. Benzene was added to the
product and the reaction mixture was refluxed with azeotropic
distillation with CF3OOH. The procedure was repeated three
times. The resulting white crystals were washed with benzene.
1,1,1ꢀTrifluoroꢀ4ꢀ(phenylsulfonyl)butꢀ3ꢀeneꢀ2,2ꢀdiol (5). The
yield was 94%, m.p. 155—158 °C. Found (%): C, 42.31; H, 3.36.

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Krasovsky et al.
C10H9F3O4S. Calculated (%): C, 42.56; H, 3.21. 1H NMR
(CDCl3) of a mixture of the E/Z isomers (75/25), δ: 7.94 (m,
2 H, Ph, E + Z); 7.76 (m, 1 H, Ph, E + Z); 7.67 (m, 2 H, Ph,
E + Z ); 7.54 (d, 1 H, C(4)H, E, J = 15.3 Hz); 7.32 (d, 1 H,
C(3)H, E, J = 15.3 Hz); 6.85 (d, 1 H, C(4)H, Z, J = 11.3 Hz);
6.75 (d, 1 H, C(3)H, Z, J = 11.3 Hz). 13C NMR, δ: 138.5, 137.9,
137.6, 135.7, 134.3, 143.2, 129.5, 127.8, 127.7, 127.6, 121.8 (q,
CF3, Z, J = 289.9 Hz); 121.8 (q, CF3, E, J = 290.0 Hz); 98.2 (q,
C(2), E, J = 32.1 Hz); 91.4 (q, C(2), Z, J = 33.8 Hz). IR,
ν/cm–1: 1670 (C=C); 3150 (OH).
1,1,1ꢀTrifluoroꢀ4ꢀ(methylsulfonyl)butꢀ3ꢀeneꢀ2,2ꢀdiol (6).
The yield was 97%, m.p. 93—94 °C. Found (%): C, 26.34;
H, 3.42. C5H7F3O4S. Calculated (%): C, 27.28; H, 3.20. A
mixture of 6a/4a (67/33). 1H NMR (CDCl3), δ: 7.61 (d, 1 H,
C(4)H, 4a, J = 15.4 Hz); 7.36 (d, 1 H, C(3)H, 4a, J = 15.4 Hz);
7.09 (d, 1 H, C(4)H, 6a, J = 15.1 Hz); 6.74 (d, 1 H, C(3)H, 6a,
J = 15.1 Hz); 3.11 (s, 3 H, 4a, Me); 3.01 (s, 3 H, 6a, Me).
13C NMR, δ: 178.6 (q, C(2), 4a, J = 38.6 Hz); 145.4, 137.5,
137.5, 129.1, 121.8 (q, CF3, 6a, J = 287.3 Hz); 115.0 (q, CF3,
4a, J = 289.9 Hz); 93.2 (q, C(2), 6a, J = 33.3 Hz); 42.5 and 42.3
(both s, Me). A mixture of diol 6a/hemihydrate 6c (33/66).
1H NMR (CD3CN), δ: 7.10 (d, 1 H, C(4)H, 6c, J = 15.2 Hz);
7.07 (d, 1 H, C(4)H, 6a, J = 15.0 Hz); 6.72 (d, 1 H, C(3)H, 6a,
J = 15.0 Hz); 6.68 (d, 1 H, C(3)H, 6c, J = 15.2 Hz); 2.99 and
2.97 (both s, 3 H each, Me). 13C NMR, δ: 139.6, 138.9, 136.8,
136.8, 123.5 (q, CF3, 6a, J = 287.2 Hz); 122.4 (q, CF3, 6c, J =
287.5 Hz); 99.6 (q, C(2), 6c, J = 32.1 Hz); 92.4 (q, C(2), 6a, J =
33.0 Hz); 42.6 (s, 6a, Me); 42.6 (s, 6c, Me). IR, ν/cm–1: 1675
(C=C); 3150 (OH).
4ꢀEthylsulfonylꢀ1,1,1ꢀtrifluorobutꢀ3ꢀeneꢀ2,2ꢀdiol (13). The
yield was 94%, white crystals, m.p. 120—123 °C. Found (%):
C, 30.53; H, 3.72. C6H9F3O4S. Calculated (%): C, 30.77;
H, 3.87. A mixture of diol 13a/hemihydrate 13c (38/62).
1H NMR (CD3CN), δ: 7.02 (d, 1 H, C(4)H, 13c, J = 15.2 Hz);
6.97 (d, 1 H, C(4)H, 13a, J = 14.9 Hz); 6.71 (d, 1 H, C(3)H,
13a, J = 14.9 Hz); 6.69 (d, 1 H, C(3)H, 13c, J = 15.3 Hz); 3.09
(m, 2 H, CH2, 13a + 13c); 1.24 (m, 3 H, Me, 13a + 13c).
13C NMR, δ: 141.2, 138.5, 136.7, 134.6, 124.0 (q, CF3, 13a, J =
287.6 Hz); 123.1 (q, CF3, 13c, J = 287.6 Hz); 99.4 (q, C(2),
13c, J = 32.6 Hz); 92.4 (q, C(2), 13a, J = 32.5 Hz); 49.0 (s, CH2);
7.2 (s, Me). IR, ν/cm–1: 1670 (C=C); 3150—3170 (OH).
1,1,1ꢀTrifluoroꢀ4ꢀ(4ꢀmethylphenylsulfonyl)butꢀ3ꢀeneꢀ2,2ꢀ
diol (14). The yield was 91%, white crystals, m.p. 137—140 °C.
Found (%): C, 44.41; H, 3.87. C11H11F3O4S. Calculated (%):
C, 44.59; H, 3.73. 1H NMR (CD3CN), δ: 7.79 (d, 2 H, Ph, J =
8.1 Hz); 7.45 (m, 2 H, Ph, J = 8.1 Hz); 7.02 (d, 1 H, C(4)H, J =
14.9 Hz); 6.75 (d, 1 H, C(3)H, J = 14.9 Hz); 2.44 (s, 3 H, Me).
13C NMR, δ: 146.5, 138.8, 137.5, 137.2, 131.1, 128.8, 123.4 (q,
CF3, J = 287.6 Hz); 92.2 (q, C(2), J = 32.6 Hz); 21.6. IR,
ν/cm–1: 1675 (C=C); 3150—3170 (OH).
1,1,1ꢀTrifluoroꢀ4ꢀ(1ꢀnaphthyl)butꢀ3ꢀeneꢀ2,2ꢀdiol (15). The
yield was 81%, white crystals, m.p. 150—153 °C. Found (%):
C, 50.39; H, 3.58. C14H11F3O4S. Calculated (%): C, 50.60;
H, 3.34. 1H NMR (CD3CN), δ: 7.80—7.45 (m, 2 H, Naphth);
7.03 (d, 1 H, C(4)H, J = 15.0 Hz); 6.75 (d, 1 H, C(3)H, J =
15.0 Hz). 13C NMR, δ: 146.5, 140.2, 138.8, 138.6, 137.6, 137.5,
137.2, 137.0, 136.9, 136.6, 131.1, 128.8, 123.2 (q, CF3, J =
287.6 Hz); 92.1 (q, C(2), J = 32.5 Hz). IR, ν/cm–1: 1665 (C=C);
3150—3170 (OH).
Then an excess of P2O5 (5 equiv.) was added. The reaction
mixture was refluxed with stirring for 30 min, cooled to ∼20 °C,
and filtered. The filtrate was concentrated in vacuo (20 Torr).
Ketone 3. The yield was 90%, white crystals rapidly deliꢀ
quesce in air, m.p. 64—70 °C. A mixture of 3a/3b (3/1) (the
spectrum of sulfone 3a is given above). 1H NMR (CDCl3), δ:
7.94 (m, 2 H, 3b, Ph); 7.72 (m, 1 H, 3b, Ph); 7.60 (m, 2 H, 3b,
Ph); 7.03 and 6.96 (both d, 1 H each, C(4)H, 3b, J = 11.6 Hz).
13C NMR, δ: 179.0 (C=O); 178.8 (C=O); 146.5, 142.5, 141.0,
140.0, 139.7, 139.6, 135.6, 135.8, 130.8, 130.2, 129.0, 129.0,
116.0 (q, CF3, 3b, J = 290.5 Hz); 115.1 (q, CF3, 3a, J =
290.3 Hz).
Dehydration of diol 6. Diol 6 (10 mmol) and dry CH2Cl2
(20 mL) were placed in a roundꢀbottom oneꢀneck flask. Then
SOCl2 (30 mmol) was added to the reaction mixture. The mixꢀ
ture was kept for ∼10 h and then concentrated in vacuo. The
yield of ketone 4a was 99%, white crystals, m.p. 56—58 °C.
Synthesis of sulfides 1 and 7—10. A solution of diol 5 or 6
(0.005 mol) in MeCN (20 mL) was placed in a flask and a
solution of thiol (0.005 mol) in a minimum amount of MeCN
(the reaction with pꢀnitrothiophenol was carried out with reꢀ
fluxing) was added. The course of the reaction was monitored by
TLC. The product was isolated by chromatography.
Phenyl βꢀ(trifluoroacetyl)vinyl sulfide (1). A mixture of the
E/Z isomers (7/5). The yield from sulfone 5 was 90% and the
yield from sulfone 6 was 86%. The NMR spectra correspond to
the data published in the literature.17
Ethyl βꢀ(trifluoroacetyl)vinyl sulfide (7). The yield from sulꢀ
fone 5 was 87% and the yield from sulfone 6 was 84%, oil.
Found (%): C, 39.01; H, 3.70. C6H7F3OS. Calculated (%):
C, 39.13; H, 3.83. A mixture of the E/Z isomers (3/2). 1H NMR
(CDCl3), δ: 8.21 (d, 1 H, C(4)H, E, J = 15.0 Hz); 7.76 (d, 1 H,
C(4)H, Z, J = 9.9 Hz); 6.57 (d, 1 H, C(3)H, Z, J = 9.9 Hz); 6.37
(d, 1 H, C(3)H, E, J = 15.0 Hz); 2.92 (m, 2 H, CH2, E + Z );
1.38 (m, 3 H, Me, E + Z). 13C NMR, δ: 178.4 (q, C=O, Z, J =
34.8 Hz); 177.2 (q, C=O, E, J = 34.9 Hz); 161.9, 157.4, 117.2
(q, CF3, E, J = 290.0 Hz); 116.9 (q, CF3, Z, J = 290.0 Hz);
113.5, 112.5, 31.4, 27.0, 15.2, 13.5. IR, ν/cm–1: 1690 (C=O).
4ꢀMethylphenyl βꢀ(trifluoroacetyl)vinyl sulfide (8). The yield
from sulfone 5 was 89% and the yield from sulfone 6 was 86%,
m.p. 73—75 °C. Found (%): C, 53.44; H, 3.77. C11H9F3OS.
Calculated (%): C, 53.65; H, 3.68. A mixture of the E/Z isomers
(2/1). 1H NMR (CDCl3), δ: 8.15 (d, 1 H, C(4)H, E, J =
14.9 Hz); 7.75 (d, 1 H, C(4)H, Z, J = 9.8 Hz); 7.27 (m, 2 H, Ph,
E + Z ); 7.16 (d, 2 H, Ph, E, J = 7.9 Hz); 7.11 (d, 2 H, Ph, Z, J =
7.9 Hz); 6.50 (d, 1 H, C(3)H, Z, J = 9.8 Hz); 6.09 (d, 1 H,
C(3)H, E, J = 14.9 Hz); 2.29 (s, 3 H, Me, E); 2.26 (s, 3 H, Me,
Z). 13C NMR, δ: 179.4 (q, C=O, Z, J = 35.1 Hz); 177.5 (q,
C=O, E, J = 35.1 Hz); 162.4, 158.2, 141.5, 140.3, 133.8, 132.5,
131.7, 131.5, 131.0, 125.8, 116.9 (q, CF3, E, J = 290.0 Hz);
116.6 (q, CF3, Z, J = 290.0 Hz); 114.4, 112.1, 21.3, 21.1. IR,
ν/cm–1: 1695 (C=O).
1ꢀNaphthyl βꢀ(trifluoroacetyl)vinyl sulfide (9). The yield from
sulfone 5 was 80% and the yield from sulfone 6 was 82%, m.p.
80—82 °C. Found (%): C, 59.133; H, 3.48. C14H9F3OS. Calcuꢀ
lated (%): C, 59.57; H, 3.21. A mixture of the E/Z isomers (7/3).
1H NMR (CDCl3), δ: 8.16 (d, 1 H, C(4)H, E, J = 14.9 Hz); 7.77
(d, 1 H, C(4)H, Z, J = 9.8 Hz); 7.55—7.10 (m, 7 H, Ph, E + Z );
6.53 (d, 1 H, C(3)H, Z, J = 9.8 Hz); 6.10 (d, 1 H, C(3)H, E, J =
14.9 Hz). 13C NMR, δ: 179.3 (q, C=O, Z, J = 35.1 Hz); 177.4
(C=O, E, J = 35.1 Hz); 160.6, 157.0, 133.1, 132.9, 132.8, 132.7,
Dehydration of diol 5. A mixture of diol 5 (10 mmol) and dry
CH2Cl2 (20 mL) was placed in a roundꢀbottom oneꢀneck flask.

Substituted vinyl sulfones and vinyl sulfides
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 11, November, 2002 2085
132.1, 129.9, 129.8, 129.6, 129.6, 129.3, 129.2, 129.2, 129.1,
129.0, 129.9, 129.8, 129.6, 125.9, 125.7, 125.4, 116.8 (q, CF3, E,
J = 290.1 Hz); 116.4 (q, CF3, Z, J = 290.1 Hz); 114.4, 112.0. IR,
ν/cm–1: 1680 (C=O).
5. L. A. Paquette and R. V. C. Carr, J. Am. Chem. Soc., 1980,
102, 7553.
6. O. De Lucchi and L. Pasquato, Gazz. Chim. Ital., 1984,
114, 349.
4ꢀNitrophenyl βꢀ(trifluoroacetyl)vinyl sulfide (10). The yield
from sulfone 5 was 76%, m.p. 113—115 °C. Found (%): C, 43.15;
H, 2.31. C10H6F3NO3S. Calculated (%): C, 43.33; H, 2.18.
1H NMR (CD3CN), δ: 8.27 (d, 1 H, Ph, J = 9.0 Hz); 8.19 (d,
2 H, C(4)H, J = 10.0 Hz); 7.79 (d, (2 H, Ph, J = 8.0 Hz); 6.87
(d, 1 H, C(3)H, J = 10.0 Hz). 13C NMR, δ: 178.7 (C=O, J =
35.3 Hz); 158.2, 143.7, 133.1, 131.5, 125.3, 116.4 (q, CF3, J =
290.2 Hz); 114.2. IR, ν/cm–1: 1685 (C=O).
7. L. A. Paquette and R. V. Williams, Tetrahedron Lett., 1981,
22, 4643.
8. R. V. C. Carr, R. V. Williams, and L. A. Paquette, J. Org.
Chem., 1983, 48, 4976.
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J. Org. Chem., 1984, 49, 596.
10. U. Azzena, S. Cossu, O. De Lucchi, and G. Melloni, Tetraꢀ
hedron Lett., 1989, 30, 1845.
Reaction of methoxythiophenol with diols 5 and 6. A solution
of diol 5 or 6 (0.005 mol) in MeCN (20 mL) was placed in a flask
and a solution of pꢀmethoxythiophenol in MeCN (0.005 or
0.011 mol) was added. The course of the reaction was monitored
by TLC. The product was isolated by chromatography.
4ꢀMethoxyphenyl βꢀ(trifluoroacetyl)vinyl sulfide (11) was preꢀ
pared only as a mixture with compound 12 although 1 equiv. of
thiol was used; the total yield was 88%, oil. A mixture of the
11. N. Ono, A. Kamimura, and A. Kaji, Tetrahedron Lett., 1986,
27, 1595.
12. N. Ono, A. Kamimura, and A. Kaji, J. Org. Chem., 1988,
53, 251.
13. H. Kenji, Y. Mitsuaki, O. Satoru, and K. Ken, J. Am. Chem.
Soc., 1984, 106, 6735.
14. T. A. Bryson, R. E. Dardis, and R. B. Gammill, Tetrahedron
Lett., 1978, 8, 743.
15. H. N. Unn and S. Lars, J. Chem. Soc., Perkin Trans. 1, 1999,
21, 3085.
16. V. G. Nenajdenko and E. S. Balenkova, Tetrahedron., 1994,
50, 12407.
17. M. Hojo, R. Masuda, and Y. Kamitori, Tetrahedron Lett.,
1976, 13, 1009.
18. N. P. Petukhova, N. E. Dontsova, O. M. Sazonova, and
E. N. Prilezhaeva, Izv. Akad. Nauk SSSR, Ser. Khim., 1978,
2654 [Bull. Acad. Sci. USSR, Div. Chem. Sci., 1978, 27, 2376
(Engl. Transl.)].
19. N. P. Petukhova, N. E. Dontsova, and E. N. Prilezhaeva,
Izv. Akad. Nauk SSSR, Ser. Khim., 1982, 2327 [Bull. Acad.
Sci. USSR, Div. Chem. Sci., 1982, 31 (Engl. Transl.)].
20. C. G. Venier, T. G. Squires, and Y. J. Chen, J. Org. Chem.,
1982, 47, 3773.
21. V. G. Nenaidenko, A. V. Sanin, A. V. Churakov, J. A. K.
Howard, and E. S. Balenkova, Khim. Geterotsikl. Soedin.,
1999, 618 [Chem. Heterocycl. Compd., 1999 (Engl. Transl.)].
22. A. L. Krasovsky, V. G. Nenajdenko, and E. S. Balenkova,
Tetrahedron, 2001, 57, 201.
23. V. G. Nenajdenko, A. L. Krasovsky, M. L. Lebedev, and
E. S. Balenkova, Synlett, 1997, 12, 1349.
24. A. L. Krasovskii, V. G. Nenaidenko, and E. S. Balenkova,
Izv. Akad. Nauk, Ser. Khim., 2001, 1329 [Russ. Chem. Bull.,
Int. Ed., 2001, 50, 1395].
1
E/Z isomers (2/1). H NMR (CDCl3), δ: 8.24 (d, 1 H, C(4)H,
E, J = 14.9 Hz); 7.79 (d, 1 H, C(4)H, Z, J = 9.9 Hz); 7.40 (m,
2 H, Ph, E + Z ); 6.98 (d, 2 H, Ph, E, J = 8.9 Hz); 6.92 (d, 2 H,
Ph, Z, J = 8.7 Hz); 6.58 (d, 1 H, C(3)H, Z, J = 9.9 Hz); 6.10 (d,
1 H, C(3)H, E, J = 14.9 Hz); 3.85 (s, 3 H, Me, E); 3.78 (s, 3 H,
Me, Z). 13C NMR, δ: 179.0 (q, C=O, Z, J = 35.1 Hz); 177.7 (q,
C=O, E, J = 35.1 Hz); 160.8, 158.1, 140.9, 140.4, 134.2, 132.8,
131.6, 131.5, 131.2, 125.1, 116.8 (q, CF3, E, J = 290.1 Hz);
116.2 (q, CF3, Z, J = 290.0 Hz); 114.8, 112.2, 55.3, 55.0.
1,1ꢀBis(4ꢀmethoxyphenylthio)ꢀ2ꢀ(trifluoroacetyl)ethane (12).
The yield was 90%, m.p. 122—125°C. Found (%): C, 53.55;
H, 4.40. C18H17F3O3S2. Calculated (%): C, 53.72; H, 4.26.
1H NMR (CDCl3), δ: 7.43 and 7.87 (both d, 4 H each, Ph, J =
8.6 Hz); 4.57 (t, 1 H, C(3)H, J = 6.7 Hz); 3.81 (s, 6 H, Me);
3.09 (d, 1 H, C(2)H, J = 6.7 Hz). 13C NMR, δ: 184.5 (q, C=O,
J = 37.0); 160.5, 136.5, 136.3, 116.0 (q, CF3, J = 290.6 Hz);
114.7, 55.3, 53.8, 36.2. IR, ν/cm–1: 1690 (C=O).
This study was financially supported by the Russian
Foundation for Basic Research (Project Nos. 00ꢀ03ꢀ
32760a and 00ꢀ03ꢀ32763a).
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Received February 1, 2002;
in revised form March 15, 2002