Reactions of carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes: Synthesis of vinyl-substituted tetrahydrofurans

Article abstract of DOI:10.1002/ejoc.200900275

The carbanions of (E)- and (Z)-1-chloro-5-(phenylsulfonyl)-pent-2-enes can be considered as vinylogues of γ-chlorocarb-anions. Because in these cases intramolecular 1,3-substitu-tion by a S_N2′ mechanism leading to vinylcyclopropanes is a relati

Full text of DOI:10.1002/ejoc.200900275

FULL PAPER
DOI: 10.1002/ejoc.200900275
Reactions of Carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes:
Synthesis of Vinyl-Substituted Tetrahydrofurans
Anna Wojtasiewicz,[a] Bartosz Lewandowski,[a] Marek Judka,[a] and Mieczysław Makosza*[a]
˛
Dedicated to Professor Binne Zwanenburg on the occasion of his 75th birthday
Keywords: Carbanions / Sulfones / Nucleophilic substitution / Oxygen heterocycles
The carbanions of (E)- and (Z)-1-chloro-5-(phenylsulfonyl)-
pent-2-enes can be considered as vinylogues of γ-chlorocarb-
anions. Because in these cases intramolecular 1,3-substitu-
tion by a SN2Ј mechanism leading to vinylcyclopropanes is
a relatively slow process these carbanions can be efficiently
trapped by active electrophilic reagents such as aldehydes.
Subsequent intramolecular SN2Ј 1,5-substitution of the aldol
anions produced gives vinyl-substituted tetrahydrofurans.
Thus, an efficient method for the synthesis of 2,3-disubsti-
tuted-5-vinyltetrahydrofurans has been elaborated.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2009)
The main problem in these reactions is the competition
between two processes: Intramolecular 1,3-substitution in
γ-halocarbanions, which gives cyclopropanes, and intermo-
lecular addition to an electrophilic partner followed by in-
tramolecular 1,5-substitution, which gives five-membered
ring compounds. Thus, manipulation of the relative rates of
these processes is of key importance. In our studies we have
tried to shift this competition in favor of intermolecular
addition and hence expand the scope of the synthesis of
five-membered-ring compounds by reactions of γ-halocar-
banions. To achieve this goal two approaches can be used:
Changing the leaving group to a less active one and intro-
ducing an additional substituent into the γ position. Al-
though it is known that trialkylammonium substituents can
act as moderately active leaving groups in SN2-type substi-
Introduction
γ-Halocarbanions are short-lived species that undergo
rapid intramolecular substitution to produce cyclopro-
panes.[1] Because of the high rate of this reaction, which is
often named a γ-elimination reaction, intermolecular reac-
tions of γ-halocarbanions with electrophilic partners were
not considered a valuable synthetic tool. In our previous
publications we have shown that γ-halocarbanions, even
though they undergo very fast intramolecular replacement
of the halogen atom to form substituted cyclopropanes, can
be efficiently trapped by active electrophilic partners like
aldehydes, Michael acceptors, and electrophilic imines to
form substituted tetrahydrofurans,[2,3] cyclopentanes,[3,4]
and pyrrolidines,[3,5] respectively (Scheme 1).
Scheme 1. Intra- and intermolecular reactions of γ-halocarbanions.
[a] Institute of Organic Chemistry, Polish Academy of Sciences,
ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
Fax: +48-22-632-66-81
tution reactions, treatment of phenyl 3-(trimethylammonio)-
propyl sulfone, alone or in the presence of benzaldehyde,
with a strong base did not result in the formation of cyclo-
E-mail: icho-s@icho.edu.pl
3732
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Reactions of Carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes
propane nor a tetrahydrofuran ring.[2] Although the carb-
anion generated added to aldehydes, the aldol-type anions
produced did not undergo 1,5-substitution. They were suffi-
ciently stable to be O-methylated and subsequent Hofmann
elimination gave substituted butadienes.[6] On the other
hand, an analogue of γ-halocarbanions that contains a phos-
phanyloxy group instead of chlorine when treated with
base underwent slow cyclization; thus it was shown to be a
valuable intermediate in the synthesis of tetrahydrofurans.[7]
Also, the introduction of methyl, phenyl, and other similar
groups into the 3-position of 3-chloropropyl phenyl sulfone
substantially decelerates the intramolecular 1,3-substitution
in the corresponding carbanions, which favors their inter-
molecular reactions with aldehydes to produce 2,3,5-trisub-
stituted tetrahydrofurans.[8]
It seems that another possible way of changing the rela-
tive rates of the inter- and intramolecular reactions of γ-
halocarbanions is to separate the β and γ carbon atoms in
the carbon chain of γ-halocarbanions by a C=C double
bond. In this case the chlorine atom will then be in an al-
lylic position and intramolecular reaction of such vi-
nylogues of γ-halocarbanions could proceed by SN2Ј 1,3-
substitution to give vinyl cyclopropanes or by SN2 1,5-sub-
stitution to give cyclopentenes. The latter reaction is pos-
sible when the double bond has a Z geometry.[9] It is known
that in analogous systems the SN2Ј reactions are slower
than those proceeding by SN2 substitution.[10] Hence, we
expected that the life-time of a vinylogue of a γ-halocarb-
anion would be much longer and, as a consequence, the
competition between intramolecular substitution and inter-
molecular addition should be shifted in favor of the inter-
molecular addition. The relative rates of the reactions pro-
ceeding by SN2Ј and SN2 mechanisms have been thoroughly
studied.[9]
Scheme 3. Reactions of (Z)-1,4-dichlorobut-2-ene with dialkyl
malonate.
The ratio of vinylcyclopropane to cyclopentene, in gene-
ral, increases with increasing hardness of the cation, on go-
ing from protic to aprotic solvents, and slightly, on chang-
ing from diethyl to dimethyl malonate.
A number of cases have been reported in the literature
of the intramolecular SN2Ј-type reaction of carbanions of
amides,[13] esters,[14] ketones,[15] or sulfones.[16] These reac-
tions involve the trans isomers of allylic chlorides and give
relatively good yields of the expected products.
The stereochemistry of the SN2Ј reaction has been inves-
tigated by many researchers. The earliest suggestion of a
stereoelectronic preference was by Winstein and co-
workers[17] who postulated that nucleophilic attack occurs
on the face of the allylic system syn to the leaving group.
The essence of the argument seems to be that this approach
displaces the π electrons in such a direction as to allow
them to attack the Cα–X bond from the rear. Clearly, syn
attack would be required in those cases in which a cyclic
transition state is implicated. Subsequent theoretical studies
have, for the most part, supported the syn attack no-
tion.[18–21]
Results and Discussion
As model compounds for the generation of vinylogues of
the γ-halocarbanions we have chosen (E)-1-chloro-5-(phen-
Bonete and Najera[11] examined the reaction of lithiated ylsulfonyl)pent-2-ene (1) and (Z)-1-chloro-5-(phenylsulfo-
3-tosylpropanal dimethyl ketal with (Z)- and (E)-1,4- nyl)pent-2-ene (2). The E isomer was obtained in a moder-
dichlorobut-2-ene (Scheme 2). They found that the reaction ate yield of 35% in the reaction of (E)-1,4-dichlorobut-2-
with the Z isomer gave the corresponding cyclopentene by ene with the carbanion of methyl phenyl sulfone in THF
intramolecular SN2 substitution, whereas with the E isomer generated by using butyllithium as base. Because the yield
intramolecular SN2Ј 1,3-substitution took place to give the of 1 was low, we tried an alternative pathway: The alky-
more stable trans-substituted vinylcyclopropane stereoselec- lation of ethyl 2-(phenylsulfonyl)acetate with (E)-1,4-dichlo-
tively. Depres and Greene[12] found that in the cycloalky- robut-2-ene followed by hydrolysis and decarboxylation. In
lation reaction of diethyl or dimethyl malonate with (Z)- the alkylation reaction the yield was even worse (23%) de-
1,4-dichlorobut-2-ene, the vinylcyclopropane as well as the spite a long reaction time. There were also some problems
cyclopentene were produced (Scheme 3).
in the hydrolysis and decarboxylation of the product ob-
Scheme 2. Reactions of tosyl-stabilized carbanions with (Z)- and (E)-1,4-dichlorobut-2-ene.
Eur. J. Org. Chem. 2009, 3732–3740
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A. Wojtasiewicz, B. Lewandowski, M. Judka, M. Makosza
˛
FULL PAPER
tained. Neither heating at reflux with NaCl in a mixture of
In contrast to the rather discouraging results of the intra-
water and DMSO nor reaction with KOH in ethanol at molecular reactions of the carbanions of 1 and 2, they
room temperature gave the desired product. Finally, (E)-1- could be efficiently trapped with active external electro-
chloro-5-(phenylsulfonyl)pent-2-ene (1) was obtained in the philes. Thus, the treatment of concentrated THF solutions
reaction of (E)-1,4-dichlorobut-2-ene with the carbanion of of sulfone 1 (1 equiv.) and aldehydes (1.5 equiv.) with
methyl phenyl sulfone in a mixture of THF and DMF gen- tBuOK at –78 °C resulted in relatively fast reactions that
erated with butyllithium and CuI as the base in 90% yield gave 2,3,5-trisubstituted derivatives of tetrahydrofuran
(Scheme 4).
(Scheme 6). The competing formation of cyclopropane was
When methyl phenyl sulfone was directly alkylated with not observed. The results are presented in Table 1.
(Z)-1,4-dichlorobut-2-ene, the majority of the starting ma-
terial was recovered and only about 1% of the desired prod-
Table 1. Synthesis of vinyltetrahydrofurans by the reaction of the
carbanion of 1 with aldehydes.
uct was obtained. On the other hand, the addition of CuI
gave the E isomer 1 in 94% yield. However, reaction of the
lithium carbanion of methyl phenyl sulfoxide, generated by
reaction with LDA, with (Z)-1,4-dichlorobut-2-ene gave the
expected substituted sulfoxide, which was subsequently oxi-
dized to give the desired sulfone 2 in an overall yield of
38% after two steps (Scheme 4).
Preliminary experiments have shown that (E)-1-chloro-5-
(phenylsulfonyl)pent-2-ene (1) treated with tBuOK in DMF
at –40 °C gives vinylcyclopropane 3 in 30% yield. On the
other hand, the reaction of (Z)-1-chloro-5-(phenylsulfonyl)-
pent-2-ene (2) under the same conditions gave a mixture of
vinylcyclopropane 3 (25%) and cyclopentene 5 (4%). In
both cases the main process was the elimination of HCl,
which gives the diene 4 (Scheme 5). This diene is rather un-
Entry
R
Product
% Yield
trans/cis diastereo-
isomeric ratio
1
2
3
4
5
6
7
8
9
Ph
6a
6b
6c
6d
6e
6f
6g
6h
6i
82
80
76
85
85
79
90
50
49
85:15
86:14
84:16
82:18
63:35
75:25
82:18
63:37
72:28
p-MeC6H4
p-ClC6H4
p-MeOC6H4
PhCH=CH
2-thienyl
3-pyridyl
2-furyl
(CH3)3C
In the reactions of (E)-1-chloro-5-(phenylsulfonyl)pent-
stable and polymerizes during the reaction. Nevertheless, 2-ene with aromatic aldehydes as well as with heterocyclic
when the reaction was arrested after a few minutes at aldehydes and cinnamaldehyde, yields of the substituted
–40 °C, we could isolate the diene 4 in moderate yield tetrahydrofurans exceeded 75%. The reaction with pivalal-
(47%).
dehyde gave a lower yield of the tetrahydrofuran, but is still
Scheme 4. Synthesis of sulfones 1 and 2.
Scheme 5. Reaction of sulfones 1 and 2 with base.
Scheme 6. Reaction of the carbanion of 1 with aldehydes.
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Reactions of Carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes
of preparative value. Pivalaldehyde is a weaker electrophile
Reactions with Michael acceptors are much more stereo-
and its addition to the carbanion is not sufficiently fast to selective than those with aldehydes; in the cases of 7a and
preclude some side-reactions such as elimination and the 7b only one diastereoisomer was formed and two in the case
formation of unidentified byproducts.
of 7c when two different orientations of Y and Z substitu-
Note that treatment of 1 with tBuOK resulted in two ents are possible. The stereochemistries of compounds 7a–
reactions, intramolecular SN2Ј substitution leading to vinyl- c are shown in Scheme 8. The yields of the cyclopentane
cyclopropane and, preferentially, elimination of HCl giving derivatives are lower than those obtained in the analogous
5-(phenylsulfonyl)penta-1,3-diene, whereas in the presence reactions with aldehydes. The Michael acceptors are less
of aldehydes vinyltetrahydrofurans were formed in high active electrophiles than aldehydes, which is the reason why
yields. We can therefore assume that the initial process com- their addition reactions are much slower. Hence, some side-
mon to both these former reactions is deprotonation to give reactions may occur to give undefined byproducts.
the carbanion of 1, which reacts in two ways: SN2Ј substitu-
The reactions of (Z)-1-chloro-5-(phenylsulfonyl)pent-2-
tion and a form of E1cb elimination. Both of these pro- ene (2) with aldehydes were also studied under conditions
cesses are relatively slow. When an aldehyde is present in analogous to the reactions of 1 with aldehydes (Scheme 9).
the reaction mixture the intermolecular aldol-type addition, The results are presented in Table 3.
leading to the aldol adduct, and the subsequent intramolec-
ular 1,5-substitution, giving vinyltetrahydrofuran, proceeds
much faster than either of these intramolecular processes.
In our previous studies we found that the substituents at
the 2- and 3-positions in 2-aryl-3-(phenylsulfonyl)tetra-
hydrofurans produced by the reaction of γ-halocarbanions
with aldehydes are always trans relative to each other.[2,3]
Scheme 9. Reaction of carbanion of 2 with aldehydes.
Also in this case, the phenylsulfonyl group and the R group
coming from the aldehyde are always trans to each other.
The vinyl group can be situated cis or trans to the phenyl- Table 3. Synthesis of vinyltetrahydrofurans by the reaction of the carb-
anion of 2 with aldehydes.
sulfonyl group and accordingly we observed the formation
of two diastereoisomeric products. In all cases the major
product was the diastereoisomer in which the vinyl group
is located trans to the phenylsulfonyl group.
Because of the relatively long life-time of the carbanion
generated from (E)-1-chloro-5-(phenylsulfonyl)pent-2-ene,
it was possible to deprotonate the starting sulfone and then
add the electrophilic partner to the reaction mixture. This
procedure was useful for the reaction of 1 with Michael
acceptors (Scheme 7, Table 2).
Entry
R
Product
% Yield trans/cis diastereo-
isomeric ratio
1
2
3
4
Ph
6a
6b
6d
6i
90
75
86
82
85:15
90:10
94:6
p-MeC6H4
p-MeOC6H4
(CH3)3C
95:5
In the reactions of (Z)-1-chloro-5-(phenylsulfonyl)pent-
2-ene (2) with aldehydes two diastereoisomeric tetra-
hydrofurans were also produced. Here the major product
was also the diastereoisomer in which the vinyl group is
located trans to the phenylsulfonyl group. Thus, the geome-
try of the C=C double bond does not affect the stereochem-
ical outcome of the reaction. In most cases the diastereo-
selectivity was somewhat better that obtained with the E
isomer 1.
In the reaction of 2 with aromatic aldehydes, the yields
of the substituted tetrahydrofurans were similar to those
obtained with the E isomer. However, the high yield pro-
duced in the reaction with pivalaldehyde was somewhat sur-
prising; a yield of 82% was obtained in the reaction of the
Z isomer and only 49% in the reaction of the E isomer,
but the intramolecular SN2Ј 1,5-substitution was probably
faster than side-reactions that could lead to byproducts and
a lower yield.
Scheme 7. Reaction of the carbanion of 1 with Michael acceptors.
Table 2. Synthesis of vinylcyclopentanes by the reaction of the
carbanion of 1 with Michael acceptors.
Entry Z, Y
Product
% Yield
1
2
3
Z = COPh, Y = H
Z = Y = CN
Z = COPh, Y = CO2Et
7a
7b
7c
68
48
70
Scheme 8. Stereochemistries of compounds 7a–c.
Eur. J. Org. Chem. 2009, 3732–3740
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3735

A. Wojtasiewicz, B. Lewandowski, M. Judka, M. Makosza
˛
FULL PAPER
ther 0.5 h, followed by the addition of (E)-1,4-dichlorobut-2-ene
(180 mg, 1.4 mmol). The mixture was stirred at 0 °C for 1 h and
quenched by addition of an aqueous solution of NH4Cl. The mix-
Conclusions
Carbanions of the (E)- (1) and (Z)-1-chloro-5-(phenylsul-
fonyl)pent-2-enes (2) react intramolecularly by two path- ture was extracted with CH2Cl2 (3ϫ10 mL), washed with water
(2ϫ10 mL), and dried with MgSO4. The solvent was evaporated
and the product purified by chromatography; yield 107 mg, 90%.
Oil. 1H NMR (500 MHz, CDCl3): δ = 2.47–2.53 (m, 2 H), 3.14–
3.19 (m, 2 H), 3.95 [d, 3J(H,H) = 5.75 Hz, 2 H], 5.61–5.73 (m, 2
H), 7.56–7.59 (m, 2 H), 7.65–7.70 (m, 1 H), 7.89–7.93 (m, 2
H) ppm. 13C NMR (125 MHz, CDCl3): δ = 25.33, 44.26, 55.17,
ways: intramolecular SN2Ј substitution to give vinylcyclo-
propane and elimination of the chloride anion in a kind of
homo-E1cb process to give substituted butadienes, the lat-
ter process being somewhat faster. When these carbanions
are generated in the presence of active electrophilic alde-
hydes, the addition of the carbanions followed by intramo-
lecular SN2Ј substitution of the resulting aldol anion is the
fastest process, which produces vinyl-substituted tetra-
hydrofurans in good yields. The intramolecular reactions
128.05, 128.60, 129.32, 130.35, 133.80, 138.89 ppm. IR (film): ν =
˜
3065, 2955, 2930, 1585, 1479, 1447, 1306, 1148, 1086, 971, 734,
689, 598, 567, 535 cm–1. MS (EI, 70 eV): m/z (%) = 244 (Ͻ1)
[M]+, 209 (76), 143 (100), 125 (14), 102 (14), 77 (18), 67 (50), 41
(1,3- and 1,5-substitutions, and the elimination of Cl–) of (18). HRMS (ESI): calcd. for C11H13ClNaO2S 267.0217; found
267.0205. C11H13ClO2S (244.74): calcd. C 53.98, H 5.35, Cl 14.49,
S 13.10; found C 53.83, H 5.36, Cl 14.57, S 13.13.
the carbanions 1 and 2 are relatively slow processes. Thus,
the carbanions can be generated in advance before addition
of base-sensitive electrophiles such as Michael acceptors
and hence substituted vinylcyclopentanes can be produced
in these reactions.
(Z)-1-Chloro-5-(phenylsulfinyl)pent-2-ene: Phenyl methyl sulfoxide
(5 g, 35.5 mmol) dissolved in THF (20 mL) was added to a solution
of LDA in THF (37.4 mmol) cooled to –20 °C. The mixture was
stirred for 1 h, cooled to –70 °C, and (Z)-1,4-dichlorobut-2-ene
(5.35 g, 42 mmol) in THF (20 mL) was added. The mixture was
stirred at –70 °C for 1 h, warmed to room temperature, stirred for
an additional 24 h, and treated with aqueous NH4Cl. The product
was extracted with CH2Cl2 (3ϫ100 mL), washed with water
(2ϫ100 mL), and dried with MgSO4. The solvent was evaporated
and the product purified by chromatography; yield 3.5 g, 45%. Oil.
1H NMR (500 MHz, CDCl3): δ = 2.35–2.43 (m, 1 H), 2.59–2.68
(m, 1 H), 2.79–2.92 (m, 2 H), 4.04 [d, 3J(H,H) = 7.8 Hz, 2 H], 5.58–
5.64 (m, 1 H), 5.70–5.77 (m, 1 H), 7.49–7.56 (m, 3 H), 7.60–7.64
(m, 2 H) ppm. 13C NMR (125 MHz, CDCl3): δ = 19.77, 38.62,
55.73, 123.84, 127.78, 129.16, 130.72, 130.96, 143.34 ppm. IR
Experimental Section
General: Reactions requiring anhydrous conditions were conducted
in flame-dried apparatus under a static atmosphere of argon. Or-
ganic extracts were evaporated at 5–20 Torr by using a rotary evap-
orator. Samples were freed of remaining traces of solvents under
high vacuum (0.1 Torr). Tetrahydrofuran was distilled from potas-
sium/benzophenone. All reactions were magnetically stirred and
monitored by thin-layer chromatography using Macherey–Nagel
Alugram SiO2 G/UV254 precoated aluminium foil sheets (layer
thickness 0.25 mm). Compounds were visualized by UV irradiation
(254 nm). Column chromatography was performed on Fisher Sci-
entific Matrex silica 60 (35–70 micron). Melting points were mea-
sured with a Griffin electrothermal apparatus and are uncorrected.
IR spectra were recorded with a Perkin–Elmer Spectrum One FT-
IR spectrometer as thin films supported on sodium chloride plates
or in a diffuse reflectance sampling cell. Absorptions are reported
in cm–1. 1H and 13C NMR spectra were recorded with Bruker
DPX300 or DRX500 Fourier Transform spectrometers using an
internal deuterium lock. All spectra were obtained in CDCl3 solu-
tion in 5 mm diameter tubes and the chemical shift in ppm is
(film): ν = 3466, 3056, 3028, 2963, 1652, 1477, 1443, 1251, 1086,
˜
1042, 748, 692 cm–1. MS (EI, 70 eV): m/z (%) = 228 (Ͻ1) [M]+, 193
(89), 126 (48), 78 (53), 67 (100), 41 (61). HRMS (ESI): calcd. for
C11H13ClNaOS 251.0270; found 251.0259. C11H13ClOS (228.74):
calcd. C 57.76, H 5.73, Cl 15.50, S 14.02; found C 57.66, H 5.91,
Cl 15.30, S 13.85.
(Z)-1-Chloro-5-(phenylsulfonyl)pent-2-ene (2): MCPBA (2.12 g,
10.44 mmol) and NaHCO3 (0.74 g, 8.7 mmol) in CH2Cl2 (25 mL)
were stirred for 1 h at room temperature. The mixture was then
cooled to –40 °C and (Z)-1-chloro-5-(phenylsulfinyl)pent-2-ene
(2 g, 8.7 mmol) in CH2Cl2 (5 mL) was added. The mixture was
warmed to room temperature and stirred for 2 h. The organic layers
were separated, the water phase was extracted with CH2Cl2
(3ϫ100 mL), and the combined organic phases were washed with
water (2ϫ100 mL) and dried with MgSO4. The solvent was evapo-
rated and the product purified by chromatography; yield 1.83 g,
85%. Oil. 1H NMR (500 MHz, CDCl3): δ = 2.56 [dq, 3J(H,H) =
1.46, 7.90 Hz, 2 H], 3.14–3.18 (m, 2 H), 4.00 [d, 3J(H,H) = 7.90 Hz,
2 H], 5.51–5.57 (m, 1 H), 5.69–5.75 (m, 1 H), 7.57–7.61 (m, 2 H),
7.66–7.70 (m, 1 H), 7.91–7.94 (m, 2 H) ppm. 13C NMR (125 MHz,
CDCl3): δ = 20.68, 38.443, 55.22, 128.01, 128.03, 129.36, 129.81,
quoted relative to the residual signals of chloroform (δH
=
7.26 ppm, δC = 77.0 ppm) as the internal standard unless otherwise
1
specified. Multiplicities in the H NMR spectra are described as: s
= singlet, d = doublet, t = triplet, q = quartet, quint. = quintet, m
= multiplet. Coupling constants (J) are reported in Hz. Electron
spray ionization (ES) mass spectrometry was performed with either
a Micromass LCT TOF spectrometer or a Waters-Micromass
ZMD spectrometer. High-resolution mass spectra (HRMS) were
obtained by peak matching using polyethylene glycols as a stan-
dard. Ion mass/charge (m/z) ratios are reported in atomic mass
units followed, in parentheses, by the peak intensity relative to the
base peak (100%). Mass spectra were recorded of samples judged
133.85, 138.84 ppm. IR (film): ν = 3065, 3032, 2972, 2927, 1978,
˜
1906, 1820, 1776, 1653, 1585, 1479, 1447, 1403, 1305, 1231, 1148,
1086, 1024, 999, 986, 952, 799, 732, 689, 594, 561, 532, 439 cm–1.
MS (EI, 70 eV): m/z (%) = 244 (Ͻ1) [M]+, 209 (39), 143 (55), 125
(7), 102 (14), 77 (23), 67 (100), 51 (12), 41 (31), 39 (10). HRMS
(EI): calcd. for C11H13ClO2S 244.0325; found 244.0316.
C11H13ClO2S (244.74): C 53.98, H 5.35, Cl 14.49, S 13.10; found
C 54.06, H 5.37, Cl 14.50, S 12.82.
1
to be Ն95% pure by H and 13C NMR spectroscopy unless other-
wise stated.
(E)-1-Chloro-5-(phenylsulfonyl)pent-2-ene (1): To a solution of
methyl phenyl sulfone (156 mg, 1 mmol) in THF (5 mL), cooled to
–40 °C, nBuLi (1.05 mmol, 0.66 mL, 1.6  solution in hexane) was
added dropwise. After 5 min, CuI (96 mg, 0.5 mmol) was added,
and, after an additional 1 min, DMF (3 mL) was added. The mix-
ture was stirred at –40 °C for additional 0.5 h and at 0 °C for fur-
(E)-1-Chloro-5-(phenylsulfinyl)pent-2-ene: Obtained in a similar way
as the (Z) isomer. Yield 1.62 g, 20%. Oil. 1H NMR (500 MHz,
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Reactions of Carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes
CDCl3): δ = 2.29–2.38 (m, 1 H), 2.50–2.59 (m, 1 H), 2.78–2.90 (m, NMR (125 MHz, CDCl3): δ = 34.89, 71.52, 79.40, 80.22, 117.54,
2 H), 3.99–4.00 (m, 2 H), 5.64–5.77 (m, 2 H), 7.46–7.54 (m, 3 H),
125.71, 127.85, 128.60, 128.63, 129.33, 133.96, 136.67, 138.22,
7.58–7.62 (m, 2 H) ppm. 13C NMR (125 MHz, CDCl3): δ = 24.54, 140.47 ppm. IR (KBr): ν = 3058, 3032, 2944, 2883, 1651, 1602,
˜
44.50, 55.74, 124.00, 128.46, 129.26, 131.07, 131.55, 143.47 ppm.
1583, 1496, 1446, 1426, 1301, 1281, 1148, 1084, 1070, 1046, 1025,
992, 943, 905, 865, 836, 757, 721, 700, 688, 630, 596, 560, 501 cm–1.
MS (EI, 70 eV): m/z (%) = 172 (85), 117 (18), 105 (100), 91 (16), 77
IR (film): ν = 3463, 3055, 2956, 1720, 1665, 1477, 1443, 1250, 1087,
˜
1042, 970, 748, 692 cm–1. MS (EI, 70 eV): m/z (%) =228 (1) [M]+,
193 (100), 126 (49), 78 (23), 67 (49), 41 (12). HRMS (EI): calcd. (28), 67 (38), 51 (8), 41 (7). HRMS (ESI): calcd. for C18H18NaO3S
for C11H13ClOS 228.0377; found 228.0386. C11H13ClOS (228.74):
calcd. C 57.76, H 5.73, Cl 15.50, S 14.02; found C 57.63, H 5.59,
Cl 15.55, S 14.26.
337.0869, found 337.0860.
2-(p-Methylphenyl)-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6b):
1
trans-6b: M.p. 102–103 °C (EtOH). H NMR (400 MHz, CDCl3):
3
2-Phenylsulfonyl-1-vinylcyclopropane (3): tBuOK (224 mg, 2 mmol)
in DMF (2 mL) was added dropwise to a solution of 1-chloro-5-
(phenylsulfonyl)pent-2-ene 1 or 2 (244 mg, 1 mmol) in DMF
(4 mL) at –30 °C under argon. After 30 min the mixture was
warmed to room temperature and after an additional 2 h an aq.
solution of NH4Cl was added, the mixture was extracted with
CH2Cl2 (3ϫ50 mL), washed with brine, and dried with MgSO4.
Column chromatography with hexane/EtOAc the gave expected
product; yield 30%. Oil. 1H NMR (500 MHz, CDCl3): δ = 1.18
[ddd, 3J(H,H) = 5.4, 6.8, 7.8 Hz, 1 H], 1.70 [dt, 3J(H,H) = 5.4,
δ = 2.05 [dt, J(H,H) = 10.77, 13.89 Hz, 1 H], 2.29 (s, 3 H), 2.62
3
3
[ddd, J(H,H) = 2.47, 5.17, 13.89 Hz, 1 H], 3.65 [ddd, J(H,H) =
3
2.47, 5.17, 10.45 Hz, 1 H], 4.61–4.68 (m, 1 H), 5.23 [dt, J(H,H) =
1.20, 10.45 Hz, 1 H], 5.30 [d, 3J(H,H) = 5.17 Hz, 1 H], 5.40 [dt,
3J(H,H) = 1.2, 17.18 Hz, 1 H], 5.93 [ddd, 3J(H,H) = 6.6, 10.45,
17.18 Hz, 1 H], 6.98–7.06 (m, 4 H), 7.51–7.56 (m, 2 H), 7.62–7.67
(m, 1 H), 7.85–7.90 (m, 2 H) ppm. 13C NMR (100 MHz, CDCl3):
δ = 21.10, 34.31, 71.34, 79.93, 80.44, 117.75, 125.87, 128.66, 129.13,
129.40, 133.97, 136.27, 137.20, 137.84, 138.20 ppm. IR (KBr): ν =
3060, 2997, 2946, 2877, 1618, 1548, 1519, 1477, 1446, 1369, 1304,
1287, 1144, 1084, 1056, 1047, 1019, 1003, 988, 972, 940, 922, 864,
˜
3
9.3 Hz, 1 H], 2.41–2.52 (m, 2 H), 5.07 [dd, J(H,H) = 1.5, 10.1 Hz,
3
1 H], 5.22 [dd, J(H,H) = 1.4, 17.1 Hz, 1 H], 5.35–5.53 (m, 1 H), 844, 820 cm–1. MS (EI, 70 eV): m/z (%) = 186 (78), 131 (23), 119
7.50–7.95 (m, 5 H) ppm. 13C NMR (125 MHz, CDCl3): δ = 12.97, (100), 115 (12), 105 (8), 91 (20), 77 (17), 67 (35). HRMS (ESI):
22.81, 40.00, 116.69, 127.45, 129.26, 133.39, 135.14, 140.67 ppm.
calcd. for C19H20NaO3S 351.1025; found 351.1009. C19H20O3S
(328.43): calcd. C 69.48, H 6.14, S 9.76; found C 69.39, H 6.22, S
IR (KBr): ν = 2924, 2853, 1640, 1447, 1306, 1148, 1088, 738, 688,
˜
650, 586, 544 cm–1. MS (EI, 70 eV): m/z (%) = 208 (1) [M]+, 77 9.84.
(11), 67 (100), 41 (14). HRMS (EI): calcd. for C11H12O2S 208.0558;
found 208.0566.
1
cis-6b: Oil. H NMR (500 MHz, CDCl3): δ = 2.28–2.42 (m, 2 H),
2.30 (s, 3 H), 3.89 [ddd, 3J(H,H) = 5.8, 8.6, 14.4 Hz, 1 H], 4.57–
4.63 (m, 1 H), 5.19 [dt, 3J(H,H) = 1.1, 10.3 Hz, 1 H], 5.29 [dt,
3J(H,H) = 1.1, 17.2 Hz, 1 H], 5.49 [d, 3J(H,H) = 5.8 Hz, 1 H], 5.91
[ddd, 3J(H,H) = 6.8, 10.3, 17.2 Hz, 1 H], 7.06–7.13 (m, 4 H), 7.49–
7.54 (m, 2 H), 7.60–7.65 (m, 1 H), 7.86–7.90 (m, 2 H) ppm. 13C
NMR (125 MHz, CHCl3): δ = 21.04, 34.86, 71.51, 79.35, 80.10,
117.46, 125.67, 128.66, 129.26, 129.31, 133.90, 136.77, 137.45,
Reactions of Carbanions of 1 and 2 with Aromatic Aldehydes and
Michael Acceptors. General Procedure: tBuOK (224 mg, 2 mmol)
in THF (2 mL) was added dropwise to a solution of 1-chloro-5-
(phenylsulfonyl)pent-2-ene 1 or 2 (244 mg, 1 mmol) and an alde-
hyde (1.5 mmol) in THF (4 mL) at –30 °C under argon. After
30 min the mixture was warmed to room temperature and after an
additional 30 min an aq. solution of NH4Cl was added, the mixture
was extracted with CH2Cl2 (3ϫ50 mL), and the extracts were
washed with brine and dried with MgSO4. The products were iso-
lated and purified by column chromatography using hexane/ethyl
acetate as eluent.
137.60, 138.28 ppm. IR (film, CH Cl ): ν = 3062, 2922, 1585, 1514,
˜
2
2
1447, 1305, 1180, 1149, 1086, 1070, 991, 928, 813, 757, 720, 689,
607, 560, 508 cm–1. MS (EI, 70 eV): m/z (%) = 186 (41), 131 (14),
119 (100), 105 (11), 91 (28), 77 (25), 67 (33), 51 (10), 41 (10).
HRMS (ESI): calcd. for C19H20NaO3S 351.1025; found 351.1042.
2-Phenyl-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6a): trans-6a: 2-(p-Chlorophenyl)-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6c):
1
1
3
M.p. 114–115 °C (EtOH). H NMR (500 MHz, CDCl3): δ = 2.06 trans-6c: Oil. H NMR (400 MHz, CDCl3): δ = 2.02 [dt, J(H,H)
[dt, 3J(H,H) = 10.17, 13.80 Hz, 1 H], 2.63 [ddd, 3J(H,H) = 2.43,
= 10.17, 13.88 Hz, 1 H], 2.60 [ddd, J(H,H) = 2.47, 5.50, 13.88 Hz,
1 H], 3.61 [ddd, 3J(H,H) = 2.61, 5.50, 10.17 Hz, 1 H], 4.61–4.69
(m, 1 H), 5.25 [dt, 3J(H,H) = 1.24, 10.45 Hz, 1 H], 5.33 [d, 3J(H,H)
3
3
5.30, 13.80 Hz, 1 H], 2.68 [ddd, J(H,H) = 2.43, 5.35, 10.17 Hz, 1
H], 4.67 [dt, 3J(H,H) = 6.4, 10.17 Hz, 1 H], 5.24 [d, J(H,H) = 1.10,
10.4 Hz, 1 H], 5.34 [d, J(H,H) = 5.35 Hz, 1 H], 5.41 [dt, J(H,H) = 5.50 Hz, 1 H], 5.41 [dt, 3J(H,H) = 1.24, 17.19 Hz, 1 H], 5.92
3
3
= 1.10, 17.2 Hz, 1 H], 5.94 [ddd, 3J(H,H) = 6.4, 10.4, 17.2 Hz, 1
H], 7.12–7.16 (m, 2 H), 7.21–7.26 (m, 3 H), 7.51–7.56 (m, 2 H), 7.20–7.24 (m, 2 H), 7.53–7.59 (m, 2 H), 7.65–7.70 (m, 1 H), 7.86–
7.62–7.67 (m, 1 H), 7.86–7.90 (m, 2 H) ppm. 13C NMR (125 MHz, 7.90 (m, 2 H) ppm. 13C NMR (100 MHz, CDCl3): δ = 34.36, 71.26,
CDCl3): δ = 34.28, 71.34, 80.01, 80.49, 117.74, 125.94, 128.07, 79.21, 80.54, 118.04, 127.35, 128.60, 128.64, 129.51, 133.89, 134.15,
128.46, 128.64, 129.40, 133.99, 136.21, 138.20, 140.18 ppm. IR 135.91, 138.05, 138.71 ppm. IR (KBr): ν = 3069, 2992, 2948, 2881,
[ddd, 3J(H,H) = 6.46, 10.45, 17.19 Hz, 1 H], 7.09–7.13 (m, 2 H),
˜
(KBr): ν = 3033, 2997, 2957, 2875, 1603, 1583, 1494, 1456, 1447, 1600, 1582, 1492, 1446, 1414, 1367, 1303, 1286, 1145, 1083, 1057,
˜
1366, 1303, 1287, 1144, 1084, 1048, 1002, 971, 938, 913, 855, 788,
761, 751, 720, 700, 690, 607, 561, 545, 515, 488 cm–1. HRMS (ESI):
calcd. for C18H18NaO3S 337.0869, found 337.0875. C18H18O3S
(314.41): calcd. C 68.76, H 5.77, S 10.20; found C 68.62, H 5.96, S
10.41.
1046, 1013, 987, 972, 928, 860, 840, 826, 754, 723, 689, 632, 608,
564, 548, 531, 496, 457 cm–1. MS (EI, 70 eV): m/z (%) = 307 (13),
279 (19), 215 (16), 201 (36), 187 (43), 171 (66), 143 (17), 106 (34),
92 (25), 77 (17), 63 (28), 43 (100). HRMS (ESI): calcd. for
C18H17ClNaO3S 371.0479; found 371.0497.
1
1
cis-6a: Oil. H NMR (500 MHz, CDCl3): δ = 2.34–2.46 (m, 2 H), cis-6c: Oil. H NMR (400 MHz, CDCl3): δ = 2.27–2.40 (m, 2 H),
3.95 [ddd, 3J(H,H) = 5.81, 8.66, 14.47 Hz, 1 H], 4.62–4.68 (m, 1
H), 5.24 [dt, J(H,H) = 1.10, 10.34 Hz, 1 H], 5.34 [dt, J(H,H) =
3.83 [ddd, 3J(H,H) = 6.05, 8.93, 14.71 Hz, 1 H], 4.55–4.62 (m, 1
H), 5.22 [dt, J(H,H) = 1.10, 10.31 Hz, 1 H], 5.31 [dt, 3J(H,H) =
3
3
3
3
3
1.10, 17.14 Hz, 1 H], 5.55 [d, J(H,H) = 5.81 Hz, 1 H], 5.95 [ddd,
1.10, 17.19 Hz, 1 H], 5.50 [d, J(H,H) = 6.05 Hz, 1 H], 5.91 [ddd,
3J(H,H) = 6.77, 10.34, 17.14 Hz, 1 H], 7.24–7.32 (m, 5 H), 7.53–
7.57 (m, 2 H), 7.64–7.68 (m, 1 H), 7.90–7.92 (m, 2 H) ppm. 13C
3J(H,H) = 6.88, 10.31, 17.19 Hz, 1 H], 7.20–7.28 (m, 4 H), 7.51–
7.57 (m, 2 H), 7.63–7.68 (m, 1 H), 7.85–7.90 (m, 2 H) ppm. 13C
Eur. J. Org. Chem. 2009, 3732–3740
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
3737

A. Wojtasiewicz, B. Lewandowski, M. Judka, M. Makosza
˛
FULL PAPER
NMR (100 MHz, CDCl3): δ = 35.12, 71.49, 78.65, 80.33, 117.79,
3
5.33 (m, 1 H), 5.89 [ddd, J(H,H) = 6.8, 10.3, 17.1 Hz, 1 H], 5.94
127.18, 128.55, 128.72, 129.41, 133.69, 134.11, 136.38, 138.06,
[dd, 3J(H,H) = 6.1, 15.8 Hz, 1 H], 6.43 [dd, 3J(H,H) = 0.9, 15.8 Hz,
139.07 ppm. IR (KBr): ν = 3083, 3068, 2939, 2885, 1599, 1582, 1 H], 7.20–7.4 (m, 3 H), 7.26–7.29 (m, 2 H), 7.53–7.57 (m, 2 H),
˜
1493, 1446, 1412, 1313, 1303, 1295, 1287, 1148, 1085, 1054, 1012,
7.60–7.65 (m, 1 H), 7.91–7.96 (m, 2 H) ppm. 13C NMR (125 MHz,
CDCl3): δ = 34.29, 69.60, 78.61, 79.67, 117.56, 126.57, 127.06,
986, 930, 919, 844, 815, 758, 724, 688, 619, 603, 592, 554, 512 cm–1.
MS (EI, 70 eV): m/z (%) = 206 (78), 151 (9), 139 (100), 115 (22), 127.97, 128.49, 128.65, 129.40, 131.71, 134.07, 135.96, 136.62,
77 (22), 67 (44), 51 (8), 41 (10). HRMS (ESI): calcd. for
C18H17ClNaO3S 371.0479; found 371.0476.
138.35 ppm. IR (film CH Cl ): ν = 3061, 3028, 2934, 1725, 1495,
˜
2 2
1447, 1305, 1149, 1086, 967, 929, 847, 752, 723, 690, 604, 554 cm–1.
HRMS (ESI): calcd. for C20H20NaO3 363.1025; found 363.1020.
2-(p-Methoxyphenyl)-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6d):
trans-6d: M.p. 70–71 °C (EtOH). 1H NMR (400 MHz, CDCl3): δ
3-Phenylsulfonyl-2-(2-thienyl)-5-vinyltetrahydrofuran (6f): trans-6f:
3
3
1
3
= 2.07 [dt, J(H,H) = 10.20, 13.80 Hz, 1 H], 2.64 [ddd, J(H,H) =
Oil. H NMR (400 MHz, CDCl3): δ = 2.14 [dt, J(H,H) = 10.04,
13.89 Hz, 1 H], 2.70 [ddd, 3J(H,H) = 3.02, 5.78, 13.89 Hz, 1 H],
3.75 [ddd, 3J(H,H) = 3.02, 5.50, 10.04 Hz, 1 H], 4.60–4.67 (m, 1
2.71, 5.65, 13.80 Hz, 1 H], 3.65 [ddd, 3J(H,H) = 2.71, 5.65,
10.20 Hz, 1 H], 3.76 (s, 3 H), 4.60–4.67 (m, 1 H), 5.24 [dt, J(H,H)
3
3
3
3
= 1.24, 10.40 Hz, 1 H], 5.26 [d, J(H,H) = 5.65 Hz, 1 H], 5.40 [dt,
H), 5.22 [dt, J(H,H) = 1.24, 10.45 Hz, 1 H], 5.39 [dt, J(H,H) =
1.24, 17.19 Hz, 1 H], 5.54 [d, J(H,H) = 5.50 Hz, 1 H], 5.90 [ddd,
3J(H,H) = 1.24, 17.18 Hz, 1 H], 5.93 [ddd, J(H,H) = 6.61, 10.40,
3
3
17.18 Hz, 1 H], 6.71–6.80 (m, 2 H), 7.00–7.08 (m, 2 H), 7.48–7.59 3J(H,H) = 6.60, 10.45, 17.19 Hz, 1 H], 6.59 [dt, 3J(H,H) = 1.24,
(m, 2 H), 7.59–7.69 (m, 1 H), 7.83–7.90 (m, 2 H) ppm. 13C NMR
(100 MHz, CDCl3): δ = 34.32, 55.24, 71.09, 79.86, 80.27, 113.82, 3J(H,H) = 1.24, 5.09 Hz, 1 H], 7.51–7.57 (m, 2 H), 7.63–7.68 (m,
117.73, 127.31, 128.59, 129.37, 132.05, 133.95, 136.24, 138.19,
1 H), 7.85–7.90 (m, 2 H) ppm. 13C NMR (100 MHz, CDCl3): δ =
159.38 ppm. IR (KBr): ν = 3035, 2997, 2945, 2874, 2836, 1616, 33.89, 71.28, 76.64, 80.54, 117.88, 124.74, 125.36, 126.70, 128.59,
3.58 Hz, 1 H], 6.80 [dd, 3J(H,H) = 3.58, 5.09 Hz, 1 H], 7.16 [dd,
˜
1589, 1517, 1466, 1446, 1438, 1375, 1308, 1301, 1249, 1183, 1144,
1113, 1084, 1044, 1032, 1004, 988, 926, 866, 834, 788, 750, 719,
129.42, 134.10, 136.06, 137.93, 143.34 ppm. IR (KBr): ν = 3065,
˜
2977, 2929, 2873, 1584, 1479, 1447, 1306, 1206, 1148, 1119, 1084,
688, 635, 606, 562, 555, 518 cm–1. MS (EI, 70 eV): m/z (%) = 344 1056, 1037, 998, 939, 872, 857, 844, 782, 754, 717, 705, 691, 638,
(Ͻ1) [M]+, 202 (78), 147 (13), 135 (100), 77 (10), 67 (11). HRMS
(EI): calcd. for C19H20O4S 344.1082; found 344.1090. C19H20O4S
(344.43): calcd. C 66.26, H 5.85, S 9.31; found C 66.36, H 5.79, S
9.41.
607, 594, 557, 504 cm–1. MS (EI, 70 eV): m/z (%) = 178 (56), 123
(18), 111 (100), 97 (11), 77 (12), 67 (29), 45 (8), 39 (8). HRMS
(ESI): calcd. for C16H16NaO3S2 343.0433; found 343.0424.
1
3
cis-6f: Oil. H NMR (400 MHz, CDCl3): δ = 2.37 [dt, J(H,H) =
1
cis-6d: Oil. H NMR (400 MHz, CDCl3): δ = 2.28–2.47 (m, 2 H), 9.07, 13.06 Hz, 1 H], 2.45–2.53 (m, 1 H), 3.99 [ddd, 3J(H,H) = 5.91,
3.77 (s, 3 H), 3.89 [ddd, 3J(H,H) = 6.18, 8.70, 14.95 Hz, 1 H], 4.57–
9.07, 14.44 Hz, 1 H], 4.60–4.67 (m, 1 H), 5.21 [dt, J(H,H) = 1.24,
3
3
3
4.66 (m, 1 H), 5.20 [dt, J(H,H) = 1.24, 10.31 Hz, 1 H], 5.30 [dt,
10.31 Hz, 1 H], 5.31 [dt, J(H,H) = 1.24, 17.19 Hz, 1 H], 5.68 [d,
3
3J(H,H) = 1.24, 17.19 Hz, 1 H], 5.44 [d, J(H,H) = 6.18 Hz, 1 H], 3J(H,H) = 5.91 Hz, 1 H], 5.89 [ddd, 3J(H,H) = 6.87, 10.31,
3
3
5.91 [ddd, J(H,H) = 6.87, 10.31, 17.19 Hz, 1 H], 6.75–6.84 (m, 2
17.19 Hz, 1 H], 6.75 [dt, J(H,H) = 1.24, 3.58 Hz, 1 H], 6.85 [dd,
H), 7.10–7.19 (m, 2 H), 7.46–7.55 (m, 2 H), 7.59–7.66 (m, 1 H), 3J(H,H) = 3.58, 5.08 Hz, 1 H], 7.18 [dd, J(H,H) = 1.24, 5.08 Hz,
3
7.83–7.89 (m, 2 H) ppm. 13C NMR (100 MHz, CDCl3): δ = 34.79, 1 H], 7.50–7.56 (m, 2 H), 7.61–7.67 (m, 1 H), 7.86–7.90 (m, 2
55.27, 71.26, 79.21, 79.94, 113.94, 117.47, 127.15, 128.57, 129.29,
132.25, 133.92, 136.76, 138.20, 159.33 ppm. IR (film, CH Cl ): ν =
H) ppm. 13C NMR (100 MHz, CDCl3): δ = 33.89, 71.53, 76.25,
79.97, 117.89, 125.10, 125.41, 126.92, 128.58, 129.37, 134.07,
˜
2
2
3065, 2935, 2838, 1612, 1585, 1513, 1447, 1305, 1250, 1176, 1149,
1086, 1070, 1032, 927, 836, 756, 720, 689, 608 cm–1. MS (EI,
70 eV): m/z (%) = 202 (33), 147 (10), 135 (100), 121 (9), 115 (8), 103
(9), 91 (11), 77 (28), 67 (15). HRMS (ESI): calcd. for C19H20NaO4S
367.0975; found 367.0974.
136.16, 138.00, 143.97 ppm. IR (KBr): ν = 3070, 2934, 2872, 1447,
˜
1305, 1150, 1086, 1038, 927, 852, 758, 722, 689, 597, 556 cm–1.
HRMS (ESI): calcd. for C16H16NaO3S2 343.0433; found 343.0416.
3-Phenylsulfonyl-2-(3-pyridyl)-5-vinyltetrahydrofuran (6g): trans-6g:
M.p. 98 °C (EtOH). 1H NMR (400 MHz, CDCl3): δ = 2.06 [dt,
3-(Phenylsulfonyl)-2-styryl-5-vinyltetrahydrofuran (6e): trans-6e: Oil. 3J(H,H) = 10.17, 13.89 Hz, 1 H], 2.65 [ddd, J(H,H) = 2.75, 5.64,
3
1H NMR (400 MHz, CDCl3): δ = 2.05 [ddd, 3J(H,H) = 10.03,
13.89 Hz, 1 H], 3.66 [ddd, 3J(H,H) = 2.75, 5.77, 10.17 Hz, 1 H],
3
3
10.03, 13.61 Hz, 1 H], 2.68 [ddd, J(H,H) = 3.72, 6.05, 13.61 Hz, 1
4.64–4.72 (m, 1 H), 5.27 [dt, J(H,H) = 1.23, 10.45 Hz, 1 H], 5.36
3
3
3
H], 3.58 [ddd, J(H,H) = 3.72, 6.73, 10.03 Hz, 1 H], 4.50–4.57 (m,
[d, J(H,H) = 5.77 Hz, 1 H], 5.42 [dt, J(H,H) = 1.23, 17.18 Hz, 1
H], 5.92 [ddd, 3J(H,H) = 6.60, 10.45, 17.18 Hz, 1 H], 7.20 [dd,
3J(H,H) = 0.41, 4.81 Hz, 1 H], 7.53–7.59 (m, 3 H), 7.65–7.70 (m,
3
3
1 H), 4.82 [dt, J(H,H) = 1.10, 6.73 Hz, 1 H], 5.22 [dt, J(H,H) =
3
1.24, 10.45 Hz, 1 H], 5.37 [dt, J(H,H) = 1.24, 17.19 Hz, 1 H], 5.86
[ddd, J(H,H) = 6.60, 10.45, 17.19 Hz, 1 H], 5.93 [dd, J(H,H) = 1 H), 7.86–7.91 (m, 2 H), 8.35 [d, 3J(H,H) = 1.93 Hz, 1 H], 8.49
3
3
6.73, 15.81 Hz, 1 H], 6.33 [d, J(H,H) = 15.81 Hz, 1 H], 7.17–7.30 [dd, 3J(H,H) = 1.38, 4.81 Hz, 1 H] ppm. 13C NMR (100 MHz,
3
(m, 5 H), 7.53–7.59 (m, 2 H), 7.60–7.66 (m, 1 H), 7.88–7.96 (m, 2
H) ppm. 13C NMR (100 MHz, CDCl3): δ = 33.87, 68.82, 79.42,
80.02, 117.86, 126.55, 126.60, 128.00, 128.45, 128.65, 129.43,
CDCl3): δ = 34.36, 70.96, 78.01, 80.65, 118.16, 123.30, 128.57,
129.58, 133.80, 134.32, 135.58, 135.70, 137.88, 147.78, 149.53 ppm.
IR (KBr): ν = 3065, 3016, 2961, 2893, 1591, 1576, 1480, 1447, 1424,
˜
132.61, 134.08, 135.85, 136.33, 138.18 ppm. IR (KBr): ν = 3058,
1361, 1339, 1324, 1303, 1145, 1085, 1062, 1024, 1005, 938, 816,
781, 750, 722, 690, 626, 571, 536, 521 cm–1. MS (EI, 70 eV): m/z
(%) = 316 (Ͻ1) [M]+, 173 (100), 158 (11), 145 (10), 118 (28), 106
(91), 91 (10), 77 (18), 67 (39), 51 (9), 41(8). HRMS (ESI): calcd.
˜
2955, 2886, 1599, 1583, 1496, 1477, 1443, 1370, 1301, 1145, 1084,
1051, 973, 965, 931, 873, 846, 778, 748, 717, 689, 630, 602, 577,
549 cm–1. MS (EI, 70 eV): m/z (%) = 198 (100), 143 (14), 131 (49),
115 (16), 91 (14), 77 (11), 67 (11). HRMS (ESI): calcd. for for C17H17NO3S 316.1002; found 316.0991. C17H17NO3S (315.39):
C20H20NaO3S 363.1025; found 363.1020.
calcd. C 64.74, H 5.43, N 4.44, S 10.17; found C 64.61, H 5.41, N
4.33, S 10.29.
1
3
cis-6e: Oil. H NMR (500 MHz, CDCl3): δ = 2.31 [dt, J(H,H) =
9.3, 12.9 Hz, 1 H], 2.42 [ddd, 3J(H,H) = 5.8, 8.3, 12.9 Hz, 1 H],
3.69 [ddd, 3J(H,H) = 6.8, 8.3, 9.3 Hz, 1 H], 4.50–4.56 (m, 1 H),
1
cis-6g: Oil. H NMR (500 MHz, CDCl3): δ = 2.34–2.45 (m, 2 H),
3
3.87 [dt, J(H,H) = 6.5, 8.8 Hz, 1 H], 4.60–4.66 (m, 1 H), 5.24 [dt,
4.98–5.02 (m, 1 H), 5.20 [dt, 3J(H,H) = 0.9, 10.3 Hz, 1 H], 5.28– 3J(H,H) = 1.0, 10.3 Hz, 1 H], 5.33 [dt, J(H,H) = 1.0, 17.1 Hz, 1
3
3738
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2009, 3732–3740

Reactions of Carbanions of 1-Chloro-5-(phenylsulfonyl)pent-2-enes
H], 5.54 [d, 3J(H,H) = 6.5 Hz, 1 H], 5.93 [ddd, 3J(H,H) = 6.8, 10.3,
116.75, 129.01, 129.33, 133.88, 138.24, 138.30 ppm. IR (film,
17.1 Hz, 1 H], 7.23–7.25 (m, 1 H), 7.52–7.57 (m, 2 H), 7.63–7.69 CH Cl ): ν = 2959, 2906, 1479, 1447, 1365, 1307, 1149, 1086, 1029,
˜
2
2
(m, 2 H), 7.86–7.90 (m, 2 H), 8.51 (br. s, 2 H) ppm. 13C NMR
997, 930, 758, 719, 690, 597, 551 cm–1. HRMS (ESI): calcd. for
(125 MHz, CDCl3): δ = 35.15, 71.24, 77.48, 80.56, 117.98, 123.51, C16H22NaO3S 317.1182; found 317.1187.
128.52, 128.60, 129.51, 134.27, 136.20, 136.28, 138.04, 147.37,
2-Benzoyl-3-phenyl-4-(phenylsulfonyl)-1-vinylcyclopentane
(7a):
148.96 ppm.. IR (film, CH Cl ): ν = 3062, 2935, 1580, 1479, 1447,
˜
1
2
2
M.p. 191 °C (EtOH). H NMR (500 MHz, CDCl3): δ = 2.23–2.31
1429, 1305, 1150, 1086, 1071, 1024, 929, 757, 723, 689, 600,
562 cm–1. HRMS (EI): calcd. for C17H17NO3S 316.1002; found
316.1014.
3
(m, 1 H), 2.79 [ddd, J(H,H) = 3.5, 7.6, 14.00 Hz, 1 H], 3.16–3.24
3
(m, 1 H), 3.72–3.78 (m, 1 H), 3.92–3.97 (m, 2 H), 4.92 [d, J(H,H)
= 10.3 Hz, 1 H], 5.00 [d, 3J(H,H) = 17.1 Hz, 1 H], 5.69 [ddd,
3J(H,H) = 7.6, 10.3, 17.1 Hz, 1 H], 6.86–6.90 (m, 2 H), 6.99–7.03
(m, 3 H), 7.22–7.27 (m, 2 H), 7.33–7.36 (m, 2 H), 7.38–7.42 (m, 1
H), 7.44–7.48 (m, 1 H), 7.51–7.55 (m, 2 H), 7.74–7.78 (m, 2
H) ppm. 13C NMR (125 MHz, CDCl3): δ = 33.01, 48.30, 51.64,
61.23, 68.99, 116.51, 126.91, 127.06, 128.18, 128.26, 128.56, 128.65,
128.92, 132.95, 133.45, 137.49, 137.99, 140.13, 199.74 ppm. IR
2-(2-Furyl)-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6h): trans-6h:
M.p. 96–97 °C (EtOH). 1H NMR (500 MHz, CDCl3): δ = 2.21
3
[ddd, J(H,H) = 10.33, 10.33, 13.69 Hz, 1 H], 2.76 [ddd, 3J(H,H)
= 4.12, 6.34, 13.69 Hz, 1 H], 4.03 [ddd, 3J(H,H) = 4.12, 6.45,
10.33 Hz, 1 H], 4.56–4.62 (m, 1 H), 5.19 [dt, 3J(H,H) = 1.14,
3
3
10.39 Hz, 1 H], 5.21 [d, J(H,H) = 6.45 Hz, 1 H], 5.33 [dt, J(H,H)
3
(KBr): ν = 3069, 1661, 1596, 1580, 1446, 1303, 1243, 1218, 1142,
˜
= 1.14, 17.18 Hz, 1 H], 5.87 [ddd, J(H,H) = 6.46, 10.39, 17.18 Hz,
3
3
1085, 1002, 922, 841, 789, 768, 758, 731, 720, 698, 687, 591, 560,
537 cm–1. HRMS (ESI): calcd. for C26H24NaO3S 439.1338; found
439.1334. C26H24O3S (416.54): calcd. C 74.97, H 5.81, S 7.70;
found C 74.84, H 5.93, S 7.94.
1 H], 6.06 [d, J(H,H) = 3.27 Hz, 1 H], 6.16 [dd, J(H,H) = 1.80,
3.27 Hz, 1 H], 7.23 [d, 3J(H,H) = 1.80 Hz, 1 H], 7.47–7.51 (m, 2 H),
7.57–7.63 (m, 1 H), 7.81–7.85 (m, 2 H) ppm. 13C NMR (125 MHz,
CDCl3): δ = 33.64, 66.95, 74.13, 80.35, 109.17, 110.34, 117.87,
128.40, 129.25, 133.91, 136.35, 137.98, 142.88, 150.50 ppm. IR
2,2-Dicyano-3-phenyl-4-(phenylsulfonyl)-1-vinylcyclopentane
(7b):
(film, CH Cl ): ν = 3066, 2985, 2885, 1504, 1447, 1307, 1251, 1149,
1
˜
2
2
M.p. 117–119 °C (EtOH). H NMR (500 MHz, CDCl3): δ = 2.65–
1086, 1047, 923, 884, 750, 721, 689, 600, 565 cm–1. HRMS (ESI):
calcd. for C16H16NaO4S 327.0662; found 327.0675. C16H16O4S
(304.37): calcd. C 63.14, H 5.30, S 10.53; found C 62.92, H 5.17, S
10.75.
3
2.72 (m, 1 H), 2.74–2.81 (m, 1 H), 3.41 [dt, J(H,H) = 7.0, 7.8 Hz,
3
3
1 H], 4.07 [d, J(H,H) = 10.0 Hz, 1 H], 4.16 [ddd, J(H,H) = 8.0,
3
10.0, 17.6 Hz, 1 H], 5.50 [d, J(H,H) = 7.0 Hz, 1 H], 5.53 (s, 1 H),
6.04–6.12 (m, 1 H), 7.05–7.09 (m, 2 H), 7.16–7.30 (m, 5 H), 7.42–
7.46 (m, 1 H), 7.61–7.64 (m, 2 H) ppm. 13C NMR (125 MHz,
CDCl3): δ = 30.23, 48.92, 51.44, 54.87, 65.45, 112.75, 113.41,
122.43, 128.07, 128.38, 129.02, 129.10, 129.29, 132.18, 132.55,
1
3
cis-6h: Oil. H NMR (500 MHz, CDCl3): δ = 2.36 [dt, J(H,H) =
3
9.36, 12.91 Hz, 1 H], 2.54 [ddd, J(H,H) = 5.69, 8.36, 12.91 Hz, 1
H], 4.19 [ddd, 3J(H,H) = 6.38, 8.36, 9.36 Hz, 1 H], 4.59–4.65 (m, 1
3
3
134.08, 137.32 ppm. IR (KBr): ν = 3013, 2992, 2956, 2252, 1447,
˜
H), 5.19 [dt, J(H,H) = 1.15, 10.35 Hz, 1 H], 5.30 [dt, J(H,H) =
3
1308, 1146, 1084, 990, 941, 751, 719, 704, 683, 603, 582, 551, 498,
426 cm–1. HRMS (ESI): calcd. for C21H18N2NaO2S 385.0981;
found 385.0989. C21H18N2O2S (362.45): C 69.59, H 5.01, N 7.73,
S 8.85; found C 69.61, H 5.12, N 7.72, S 8.78.
1.15, 17.17 Hz, 1 H], 5.36 [d, J(H,H) = 6.38 Hz, 1 H], 5.86 [ddd,
3J(H,H) = 6.85, 10.35, 17.17 Hz, 1 H], 6.09 [d, 3J(H,H) = 3.28 Hz,
3
3
1 H], 6.19 [dd, J(H,H) = 1.84, 3.28 Hz, 1 H], 7.25 [d, J(H,H) =
1.84 Hz, 1 H], 7.47–7.53 (m, 2 H), 7.58–7.63 (m, 1 H), 7.83–7.86
(m, 2 H) ppm. 13C NMR (125 MHz, CDCl3): δ = 33.92, 67.45,
73.49, 80.10, 108.77, 110.40, 117.81, 128.46, 129.25, 133.92, 136.29,
Ethyl 1-Benzoyl-2-phenyl-3-(phenylsulfonyl)-5-vinylcyclopentanecar-
boxylate (7c): LDA (0.55 mmol, 0.34 mL, 1.6  solution in THF,
heptane and ethylbenzene) was added dropwise to a solution of
(E)-1-chloro-5-(phenylsulfonyl)pent-2-ene (1; 122 mg, 0.5 mmol)
and ethyl 2-benzoyl-3-phenylacrylate (210 mg, 0.75 mmol) in THF
(10 mL) at –70 °C under argon. After 30 min the mixture was
warmed to room temperature and after an additional 22.5 h an aq.
solution of NH4Cl was added, the mixture was extracted with
CH2Cl2 (3ϫ50 mL), and the extracts were washed with brine and
dried with MgSO4. Products were isolated and purified by column
chromatography using hexane/ethyl acetate as eluent; yield 70%,
trans/cis = 62:38.
138.09, 142.88, 151.67 ppm. IR (film, CH Cl ): ν = 3121, 3067,
˜
2
2
2988, 2884, 1585, 1504, 1447, 1306, 1248, 1150, 1086, 1014, 933,
917, 884, 749, 723, 689, 603, 562 cm–1. HRMS (ESI): calcd. for
C16H16NaO4S 327.0662; found 327.0661.
2-tert-Butyl-3-(phenylsulfonyl)-5-vinyltetrahydrofuran (6i): trans-6i:
1
M.p. 121–122 °C (EtOH). H NMR (400 MHz, CDCl3): δ = 0.80
3
(s, 9 H), 1.75 [ddd, J(H,H) = 9.4, 11.2, 14.0 Hz, 1 H], 2.45 [ddd,
3J(H,H) = 0.8, 5.0, 14.0 Hz, 1 H], 3.46 [ddd, 3J(H,H) = 0.8, 3.6,
3
9.4 Hz, 1 H], 4.20 [d, J(H,H) = 3.6 Hz, 1 H], 4.49–4.56 (m, 1 H),
3
3
5.15 [ddd, J(H,H) = 1.1, 1.6, 10.4 Hz, 1 H], 5.33 [ddd, J(H,H) =
3
1
1.1, 1.6, 17.2 Hz, 1 H], 5.78 [ddd, J(H,H) = 6.7, 10.4, 17.2 Hz, 1
trans-7c: M.p. 104–105 °C (EtOH). H NMR (500 MHz, CDCl3):
3
H], 7.57–7.63 (m, 2 H), 7.66–7.71 (m, 1 H), 7.92–7.96 (m, 2
H) ppm. 13C NMR (100 MHz, CDCl3): δ = 25.44, 34.53, 35.10,
66.22, 79.84, 85.49, 117.08, 128.97, 129.41, 133.99, 136.63,
δ = 0.58 [t, J(H,H) = 7.2 Hz, 3 H], 2.66–2.82 (m, 2 H), 3.40–3.47
(m, 1 H), 3.52–3.57 (m, 1 H), 3.76–3.84 (m, 1 H), 4.34–4.41 (m, 2
3
H), 4.96–5.03 (m, 2 H), 6.01 [ddd, J(H,H) = 7.9, 10.3, 17.9 Hz, 1
138.18 ppm. IR (KBr): ν = 2967, 2883, 1478, 1468, 1449, 1410,
˜
H], 6.88–6.98 (m, 5 H), 7.10–7.14 (m, 2 H), 7.20–7.24 (m, 2 H),
7.26–7.37 (m, 4 H), 7.63–7.66 (m, 2 H) ppm. 13C NMR (125 MHz,
CDCl3): δ = 12.99, 30.03, 51.14, 54.68, 60.58, 66.01, 73.22, 118.11,
127.15, 127.30, 127.76, 128.54, 128.67, 129.19, 129.47, 132.15,
133.25, 135.38, 138.30, 136.53, 138.05, 169.79, 194.93 ppm. IR
1304, 1284, 1183, 1149, 1126, 1085, 1050, 1025, 1004, 932, 788,
762, 722, 697, 634, 563, 547 cm–1. HRMS (ESI): calcd. for
C16H22NaO3S 317.1182; found 317.1171. C16H22O3S (294.42):
calcd. C 65.27, H 7.53, S 10.89; found C 65.25, H 7.34, S 10.71.
(KBr): ν = 3059, 2985, 2898, 1716, 1668, 1597, 1579, 1447, 1305,
˜
cis-6i: Oil. 1H NMR (500 MHz, CDCl3): δ = 0.85 (s, 9 H), 2.23–
2.30 (m, 1 H), 2.32–2.40 (m, 1 H), 3.65 [ddd, J(H,H) = 3.8, 5.8,
1274, 1246, 1224, 1145, 1084, 748, 700, 688, 594, 567, 541 cm–1.
HRMS (ESI): calcd. for C29H28NaO5S 511.1550; found 511.1530.
C29H28O5S (488.60): calcd. C 71.29, H 5.78, S 6.56; found C 71.43,
H 5.63, S 6.43.
3
3
3
9.6 Hz, 1 H], 4.28 [d, J(H,H) = 3.8 Hz, 1 H], 4.51 [q, J(H,H) =
3
7.4 Hz, 1 H], 5.07–5.11 (m, 1 H), 5.16 [dt, J(H,H) = 1.1, 17.2 Hz,
3
1 H], 5.82 [ddd, J(H,H) = 7.4, 10.1, 17.2 Hz, 1 H], 7.54–7.61 (m,
2 H), 7.64–7.69 (m, 1 H), 7.91–7.95 (m, 2 H) ppm. 13C NMR
cis-7c: M.p. 171–172 °C (EtOH). 1H NMR (500 MHz, CDCl3): δ
3
(125 MHz, CDCl3): δ = 25.99, 34.88, 36.08, 66.16, 81.58, 87.01, = 0.37 [t, J(H,H) = 7.2 Hz, 3 H], 2.46 [ddd, 3J(H,H) = 4.2, 7.2,
Eur. J. Org. Chem. 2009, 3732–3740
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
3739

A. Wojtasiewicz, B. Lewandowski, M. Judka, M. Makosza
˛
FULL PAPER
14.3 Hz, 1 H], 3.09 [ddd, J(H,H) = 8.1, 10.2, 14.3 Hz, 1 H], 3.23–
3
[6] M. Ma˛kosza, M. Judka, Synthesis 2003, 6, 820–822.
[7] M. Ma˛kosza, A. Wojtasiewicz, Phosphorus, Sulfur Silicon Re-
lat. Elem. 2009, 184, 857–864.
3
3.30 (m, 1 H), 3.68–3.78 (m, 2 H), 4.19 [ddd, J(H,H) = 7.2, 10.4,
10.6 Hz, 1 H], 4.76–4.82 (m, 3 H), 5.70 [dt, 3J(H,H) = 10.2,
16.7 Hz, 1 H], 6.93–7.05 (m, 5 H), 7.19–7.24 (m, 2 H), 7.30–7.39
(m, 3 H), 7.42–7.46 (m, 1 H), 7.58–7.62 (m, 2 H), 7.67–7.71 (m, 2
H) ppm. 13C NMR (125 MHz, CDCl3): δ = 12.64, 32.55, 49.24,
51.20, 61.00, 66.44, 73.57, 117.60, 126.98, 127.61, 128.06, 128.40,
128.50, 128.61, 132.51, 133.14, 136.32, 136.37, 136.64, 138.42,
´
[8] A. Brandt, M. Sniezek, A. Wojtasiewicz, M. Ma˛kosza, unpub-
˙
lished results.
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7423; b) R. M. Magid, Tetrahedron 1980, 36, 1901–1930.
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[11] P. Bonete, C. Najera, Tetrahedron 1996, 52, 4111–4122.
171.98, 192.60 ppm. IR (KBr): ν = 3078, 2985, 2952, 1721, 1678,
[12]
J.-P. Depres, A. E. Greene, J. Org. Chem. 1984, 49, 928–931.
˜
[13] H. Kim, W. J. Choi, J. Jung, S. Kim, D. Kim, J. Am. Chem.
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1583, 1449, 1290, 1255, 1238, 1215, 1143, 1084, 998, 931, 753, 735,
693, 593, 580, 546 cm–1. HRMS (ESI): calcd. for C29H28NaO5S
511.1550; found 511.1564. C29H28O5S (488.60): calcd. C 71.29, H
5.78, S 6.56; found C 71.30, H 5.76, S 6.34.
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Georg Thieme, Stuttgart, 1996, pp. 29–40; b) S. Gronert, K.
Azizian, M. A. Friedman, J. Am. Chem. Soc. 1998, 120, 3220–
3226; c) U. Habusha, E. Rozental, S. Hoz, J. Am. Chem. Soc.
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2000, 12, 1773–1774.
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Int. Ed. 2004, 53, 1846–1858.
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Received: March 13, 2009
Published Online: June 17, 2009
3740
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2009, 3732–3740