Novel stereoselective synthesis of 1-substituted 1,3-dien-2-yl sulfides via Stille coupling reactions of (E)-α-stannylvinyl sulfides with alkenyl iodides

Article abstract of DOI:10.1016/j.jorganchem.2005.10.012

(E)-α-stannylvinyl sulfides are new difunctional reagents which undergo Stille coupling reactions with alkenyl iodides to afford stereoselectively 1-substituted 1,3-dien-2-yl sulfides in good yields.

Full text of DOI:10.1016/j.jorganchem.2005.10.012

Journal of Organometallic Chemistry 691 (2006) 737–740
www.elsevier.com/locate/jorganchem
Novel stereoselective synthesis of 1-substituted 1,3-dien-2-yl sulfides via
Stille coupling reactions of (E)-a-stannylvinyl sulfides with alkenyl iodides
a,
a
b
Ming-Zhong Cai *, Dong Wang , Ping-Ping Wang
a
School of Chemistry and Chemical Engineering, Jiangxi Normal University, Jiangxi Province, Nanchang 330027, PR China
b
Department of Chemistry, Jiujiang College, Jiujiang 332000, PR China
Received 1 June 2005; received in revised form 6 October 2005; accepted 6 October 2005
Available online 10 November 2005
Abstract
(E)-a-stannylvinyl sulfides are new difunctional reagents which undergo Stille coupling reactions with alkenyl iodides to afford stere-
oselectively 1-substituted 1,3-dien-2-yl sulfides in good yields.
Ó 2005 Elsevier B.V. All rights reserved.
Keywords: (E)-a-stannylvinyl sulfide; 1,3-Dienyl sulfides; Difunctional reagent; Stille coupling; Stereoselective synthesis
1. Introduction
intermediates since vinyl sulfides are synthetically equiva-
lent to carbonyls and can be stereospecifically converted
to alkenes by nickel-catalyzed coupling reactions with Grig-
nard reagents [10]. In addition, 1,3-dienyl sulfides play a
very important role in Diels–Alder reactions, where they
impart an added level of reactivity and regioselectivity to
such cycloadditions [11]. Due to their synthetic utility, a
variety of methods have been developed for their prepara-
tion [12]. However, the stereoselective synthesis of polysub-
stituted 1,3-dienyl sulfides has rarely been reported [13].
Liebeskind et al. [14] reported that a-(tributylstannyl)thio-
phene and iodoolefins were successfully Stille-coupled to
afford different products containing sulfur-substituted
1,3-diene structural skeleton. Recently, Jin et al. [15] have
developed a convergent approach for the stereoselective
synthesis of (Z,Z)-2-alkoxy-3-alkyl(aryl)thiobuta-1,3-
dienes via Negishi coupling between a-alkyl(aryl)thio vinyl
zinc chloride and a-bromo vinyl ether. Vinylstannanes are
pivotal intermediates in a wide range of carbon–carbon
bond forming reactions [16]. The Stille coupling reactions
of vinylstannanes with alkenyl iodides provides a conve-
nient route to stereoselective synthesis of 1,3-dienes [17].
Herein, we wish to report that 1-substituted 1,3-dien-2-yl
sulfides could be synthesized by Stille coupling reactions
of (E)-a-stannylvinyl sulfides with alkenyl iodides.
The stereocontrolled synthesis of conjugated dienes is of
considerable interest in organic chemistry since such dienes
are valuable synthetic intermediates and often encountered
in natural compounds, such as insect sex pheromones and
Achillea amide [1]. The synthesis of dienes for use in the
Diels–Alder reaction is still an important challenge in
organic synthesis [2] although other elegant uses of these
compounds have been developed [3]. Conjugated dienes
are usually prepared by utilizing either a Wittig type
approach [4] or coupling reactions of stereodefined vinyl
halides with vinyl organometallic compounds catalyzed
by transition metals [5]. Recently, Whitby et al. [6] reported
the insertion of 1-lithio-1-halobutadiene into organozirco-
nocenes providing a stereocontrolled synthesis of (E,Z)-
1,3-dienes.
The synthesis of 1,3-dienes containing functional groups
is also of considerable interest in recent years. The stereose-
lective synthesis of 1,3-dienylsilanes [7], 1,3-dienyl selenides
[8] and 1,3-dienylstannanes [9] has already been described in
the literatures. 1,3-Dienyl sulfides serve as valuable versatile
*
Corresponding author.
E-mail address: caimzhong@163.com (M.-Z. Cai).
0022-328X/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2005.10.012

738
M.-Z. Cai et al. / Journal of Organometallic Chemistry 691 (2006) 737–740
2. Results and discussion
that 3f has the expected Z-configuration and the cross-cou-
pling reaction of (E)-a-stannylvinyl sulfides with alkenyl
iodides occurs with the configuration retention of both
the starting compounds 1 and the compounds 2.
In conclusion, we have developed a novel route to the
stereoselective synthesis of 1-substituted 1,3-dien-2-yl sul-
fides 3. The method has the advantages of readily available
starting materials, simple procedures, mild reaction condi-
tions and good yields. Investigations into the synthetic
applications of 1-substituted 1,3-dien-2-yl sulfides 3 are
currently in progress.
Palladium-catalyzed hydrostannylation of alkynylsul-
fides provides a simple general route for the synthesis of
(E)-a-stannylvinyl sulfides [18]. (E)-a-stannylvinyl sulfides
are new difunctional group reagents in which two synthet-
ically versatile groups are linked to the same olefinic car-
bon atom and can be considered both as vinylstannanes
and as vinyl sulfides. With a convenient route to the (E)-
a-stannylvinyl sulfides 1 we decided to establish the feasi-
bility of using 1 in Stille coupling reactions with alkenyl
iodides 2. Gratifyingly, when the coupling reactions of 1
with a variety of alkenyl iodides 2 were conducted in
DMF at room temperature using Pd(PPh3)4 and CuI as
co-catalyst (Scheme 1), fairly rapid reactions occurred
affording stereoselectively the desired coupling products 3
in good yields (Table 1).
3. Experimental
1H NMR spectra were recorded on a Bruker AC-P400
(400 MHz) spectrometer with TMS as an internal standard
using CDCl3 as the solvent. 13C NMR (100 MHz) spectra
were recorded on a Bruker AC-P400 (400 MHz) spectrom-
eter using CDCl3 as the solvent. IR spectra were deter-
mined on an FTS-185 instrument as neat films. Mass
spectra were obtained on a Finigan 8239 mass spectrome-
ter. Microanalyses were measured using a Yanaco MT-3
CHN microelemental analyser. All reactions were carried
out in pre-dried glassware (150 °C, 4 h) and cooled under
a stream of dry nitrogen. THF was freshly distilled from
sodium-benzophenone prior to its use. DMF was dried
by distillation over calcium hydride. (E)-a-stannylvinyl sul-
fides 1 were prepared by Pd(PPh3)4-catalyzed hydrostanny-
lation of alkynylsulfides with Bu3SnH in THF according to
the literature procedure [18].
It is well documented that the cross-coupling reaction
(Stille coupling) of vinylstannanes with organic halides in
the presence of a palladium catalyst occurs with retention
of configuration [16a,16d]. The E-configuration of the com-
1
pounds 3a, 3e, 3f, 3i has been proved by their H NMR
spectra which show a doublet at d = 6.08–6.89 with a cou-
pling constant of 14.8–15.6 Hz, and this is also the evidence
of the retention of the E-configuration of the starting com-
pounds 2. In addition, the Z-configuration of the com-
1
pound 3f was confirmed by the NOESY in the H NMR
spectrum. An enhancement of the allylic protons was
observed as the vinylic proton (d = 6.25) of 3f was irradi-
ated. There was no correlation between the vinylic proton
(d = 6.25) and aromatic proton. The correlation between
the vinylic proton (d = 6.25) and another vinylic proton
(d = 6.30) was also observed. The NOE results indicate
3.1. General procedure for the cross-coupling reactions
(E)-a-stannylvinyl sulfide 1 (1.0 mmol) and alkenyl
iodide 2 (1.1 mmol) were dissolved in DMF (10 ml) under
nitrogen at room temperature. Pd(PPh3)4 (0.10 mmol)
and CuI (0.75 mmol) were then added. The mixture was
stirred for 6–8 h at room temperature and monitored by
TLC (SiO2) for the disappearance of the starting (E)-a-
stannylvinyl sulfide 1. The reaction mixture was diluted
with diethyl ether (30 ml), filtered and then treated with
20% aqueous KF (10 ml) for 30 min before being dried
and concentrated. The residue was purified by column
chromatography on silica gel, eluting either with a mixture
of diethyl ether and petroleum or just petroleum.
SAr
R
H
10 mol% Pd(PPh3)4,
0.75 equiv. CuI
H
SAr
I
R
H
H
+
DMF, r.t., 6-8 h
R2
R1
(1.1 equiv.)
SnBu3
R2
R1
2
1
3
Scheme 1.
Table 1
Synthesis of 1-substituted 1,3-dien-2-yl sulfides 3a–i
Entry
R
Ar
R1
R2 Producta Yield
(%)b
3.1.1. (5Z,7E)-6-phenylthio-5,7-dodecadiene (3a)
IR (film): m (cmÀ1) 3059, 2958, 1584, 1478, 1465, 1439,
1378, 961, 737, 689; H NMR (CDCl3): d 7.26–7.08 (m,
1
2
3
4
5
6
7
8
9
a
n-C4H9
CH3OCH2 Ph
Ph
n-C4H9
n-C4H9
CH3OCH2
A(CH2)4A
CH3OCH2
H
H
H
3a
3b
3c
3d
3e
3f
79
73
76
82
69
77
71
83
72
1
n-C4H9
n-C4H9
Ph
n-C4H9
Ph
4-ClC6H4
4-ClC6H4
Ph
4-CH3C6H4 CH3OCH2
Ph A(CH2)4A
4-CH3C6H4 A(CH2)4A
4-ClC6H4 Ph
5H), 6.16 (t, J = 7.2 Hz, 1H), 6.08 (d, J = 14.8 Hz, 1H),
6.01–5.92 (m, 1H), 2.46–2.40 (m, 2H), 2.04–1.97 (m,
2H), 1.41–1.15 (m, 8H), 0.89–0.79 (m, 6H); 13C NMR
(CDCl3): d 141.5, 137.0, 133.4, 130.9, 130.2, 128.7,
127.1, 124.8, 32.0, 31.4, 30.0, 22.4, 22.3, 22.0, 14.0, 13.9;
MS: m/z 275 (M+ + 1, 100), 219 (11.3), 149 (12.5), 109
(3.8); Anal. Calc. for C18H26S: C, 78.83; H, 9.49. Found:
C, 78.59; H, 9.28%.
H
H
3g
3h
3i
n-C4H9
n-C4H9
H
All the products were characterized by IR, 1H NMR, 13C NMR, MS
and elemental analyses.
b
Isolated yield based on the 1 used.

M.-Z. Cai et al. / Journal of Organometallic Chemistry 691 (2006) 737–740
739
3.1.2. (2Z,4E)-1-methoxy-3-phenylthio-2,4-nonadiene (3b)
IR (film): m (cmÀ1) 3058, 2957, 2926, 1643, 1583, 1478,
1440, 1376, 1119, 961, 739, 690; 1H NMR (CDCl3): d
7.26–7.11 (m, 5H), 6.21 (t, J = 6.0 Hz, 1H), 6.11–6.05 (m,
2H), 4.29 (d, J = 6.4 Hz, 2H), 3.34 (s, 3H), 2.06–2.00 (m,
2H), 1.27–1.14 (m, 4H), 0.81 (t, J = 7.2 Hz, 3H); 13C
NMR (CDCl3): d 135.9, 135.7, 133.5, 130.6, 129.3, 128.8,
127.7, 125.4, 70.5, 58.3, 32.0, 31.2, 22.0, 13.9; MS: m/z
262 (M+, 18.9), 249 (39), 233 (21.5), 221 (37), 169 (68),
147 (83), 135 (94), 109 (100); Anal. Calc. for C16H22OS:
C, 73.28; H, 8.40. Found: C, 73.01; H, 8.33%.
3H); 13C NMR (CDCl3): d 144.0, 134.9, 132.9, 132.8,
130.7, 129.5, 128.0, 127.3, 72.4, 57.7, 31.3, 30.1, 22.4,
20.9, 13.9; MS: m/z 277 (M+ + 1, 44), 276 (M+, 7.3), 275
(29), 245 (100), 189 (24), 161 (37), 149 (23), 123 (25), 79
(29); Anal. Calc. for C17H24OS: C, 73.91; H, 8.70. Found:
C, 73.63; H, 8.61%.
3.1.7. (Z)-1-(1-cyclohexenyl)-1-phenylthio-2-phenylethene
(3g)
IR (film): m (cmÀ1) 3057, 3020, 2928, 2856, 1626, 1583,
1
1491, 1477, 1440, 739, 690; H NMR (CDCl3): d 7.59 (d,
J = 7.6 Hz, 2H), 7.34–7.15 (m, 8H), 7.04 (s, 1H), 6.35–
6.31 (m, 1H), 2.31–2.25 (m, 2H), 2.07–2.02 (m, 2H),
1.61–1.56 (m, 2H), 1.49–1.44 (m, 2H); 13C NMR (CDCl3):
d 137.1, 136.3, 132.2, 129.8, 129.6, 128.6, 128.4, 127.9,
127.4, 125.4, 27.6, 26.0, 22.9, 22.1; MS: m/z 292 (M+,
86), 183 (79), 141 (100), 115 (47), 109 (26); Anal. Calc.
for C20H20S: C, 82.19; H, 6.85. Found: C, 82.24; H, 6.63%.
3.1.3. (2E,4Z)-1-methoxy-4-(4-chlorophenylthio)-2,4-
nonadiene (3c)
IR (film): m (cmÀ1) 2957, 2925, 1645, 1598, 1476, 1380,
1092, 1011, 962, 814; 1H NMR (CDCl3): d 7.17 (d,
J = 8.8 Hz, 2H), 7.08 (d, J = 8.8 Hz, 2H), 6.35–6.28 (m,
2H), 6.05–6.01 (m, 1H), 3.92 (d, J = 5.6 Hz, 2H), 3.25 (s,
3H), 2.46–2.40 (m, 2H), 1.41–1.19 (m, 4H), 0.87 (t,
J = 7.2 Hz, 3H); 13C NMR (CDCl3): d 144.9, 135.2,
132.2, 130.8, 130.0, 128.9, 128.3, 128.2, 72.3, 57.9, 31.2,
30.1, 22.4, 13.9; MS: m/z 297 (M+, 11.4), 267 (36), 265
(100), 209 (12.5), 121 (6); Anal. Calc. for C16H21OSCl: C,
64.76; H, 7.08. Found: C, 64.58; H, 6.89%.
3.1.8. (Z)-1-(1-cyclohexenyl)-1-(4-methylphenylthio)-1-
hexene (3h)
IR (film): m (cmÀ1) 3022, 2926, 1632, 1598, 1492, 1448,
1
1087, 802; H NMR (CDCl3): d 7.04–6.98 (m, 4H), 6.26–
6.22 (m, 1H), 6.15 (t, J = 7.6 Hz, 1H), 2.44–2.40 (m, 2H),
2.27 (s, 3H), 2.21–2.17 (m, 2H), 2.05–2.01 (m, 2H), 1.61–
1.57 (m, 2H), 1.51–1.46 (m, 2H), 1.42–1.20 (m, 4H), 0.87
(t, J = 7.2 Hz, 3H); 13C NMR (CDCl3): d 136.2, 135.4,
134.8, 134.5, 134.0, 129.4, 127.8, 127.4, 31.7, 30.3, 27.2,
25.9, 23.0, 22.5, 22.3, 21.0, 14.0; MS: m/z 287 (M+ + 1,
100), 217 (14.1), 161 (8.7); Anal. Calc. for C19H26S: C,
79.72; H, 9.09. Found: C, 79.44; H, 9.01%.
3.1.4. (Z)-1-(1-cyclohexenyl)-1-(4-chlorophenylthio)-1-
hexene (3d)
IR (film): m (cmÀ1) 3019, 2926, 1631, 1574, 1474, 1389,
1092, 1011, 812, 742; 1H NMR (CDCl3): d 7.16 (d,
J = 8.8 Hz, 2H), 7.04 (d, J = 8.8 Hz, 2H), 6.23–6.17 (m,
2H), 2.43–2.39 (m, 2H), 2.21–2.17 (m, 2H), 2.07–2.01
(m, 2H), 1.64–1.58 (m, 2H), 1.52–1.48 (m, 2H), 1.42–1.21
(m, 4H), 0.88 (t, J = 7.2 Hz, 3H); 13C NMR (CDCl3): d
137.0, 136.3, 135.0, 134.1, 130.5, 128.7, 128.3, 128.1, 31.5,
30.4, 28.9, 27.1, 25.9, 22.9, 22.4, 14.0; MS: m/z 307 (M+,
100), 279 (7.4), 237 (17.4), 163 (8.5); Anal. Calc. for
C18H23SCl: C, 70.47; H, 7.50. Found: C, 70.18; H, 7.23%.
3.1.9. (1E,3Z)-1-phenyl-3-(4-chlorophenylthio)-1,3-
octadiene (3i)
IR (film): m (cmÀ1) 3059, 3025, 2956, 2927, 1624, 1594,
1574, 1493, 1475, 1389, 1092, 958, 814, 751, 692; 1H
NMR (CDCl3): d 7.42–7.09 (m, 9H), 6.89 (d, J = 15.6 Hz,
1H), 6.83 (d, J = 15.6 Hz, 1H), 6.42 (t, J = 7.6 Hz, 1H),
2.49–2.44 (m, 2H), 1.45–1.25 (m, 4H), 0.88 (t, J = 7.2 Hz,
3H); 13C NMR (CDCl3): d 145.5, 137.0, 135.4, 130.8,
129.4, 129.0, 128.6, 128.1, 127.6, 126.6, 31.3, 30.4, 22.5,
14.0; MS: m/z 329 (M+, 100), 273 (20.4), 185 (9.6), 129
(13.3); Anal. Calc. for C20H21SCl: C, 73.06; H, 6.39. Found:
C, 72.82; H, 6.16%.
3.1.5. (1Z,3E)-1-phenyl-2-phenylthio-5-methoxy-1,3-
pentadiene (3e)
IR (film): m (cmÀ1) 3057, 2926, 1580, 1478, 1439, 1383,
1
1116, 1039, 977, 746, 687; H NMR (CDCl3): d 7.67 (d,
J = 7.6 Hz, 2H), 7.31–7.06 (m, 9H), 6.46 (d, J = 15.2 Hz,
1H), 6.24–6.20 (m, 1H), 3.95 (d, J = 5.6 Hz, 2H), 3.22 (s,
3H); 13C NMR (CDCl3): d 139.6, 136.0, 133.3, 130.2,
129.9, 129.0, 128.3, 128.2, 127.5, 125.5, 72.3, 57.9; MS:
m/z 282 (M+, 7.8), 251 (100), 142 (17.4); Anal. Calc. for
C18H18OS: C, 76.60; H, 6.38. Found: C, 76.43; H, 6.14%.
Acknowledgments
We thank the National Natural Science Foundation of
China (Project No. 20462002) and the Natural Science
Foundation of Jiangxi Province (Project No. 0420015)
for financial support.
3.1.6. (2E,4Z)-1-methoxy-4-(4-methylphenylthio)-2,4-
nonadiene (3f)
IR (film): m (cmÀ1) 3020, 2924, 1646, 1599, 1492, 1454,
1
1379, 1123, 1087, 962, 804; H NMR (CDCl3): d 7.07 (d,
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2H), 2.27 (s, 3H), 1.41–1.26 (m, 4H), 0.88 (t, J = 7.2 Hz,
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