Highly regio- and stereocontrolled synthesis of vinyl sulfides via transition-metal-catalyzed hydrothiolation of alkynes with thiols

Article abstract of DOI:10.1021/ja983949i

Regio- and stereoselectivity in the hydrothiolation of alkynes with thiols in the presence of a variety of transition-metal catalysts is investigated in detail. Among the catalysts employed, RhCl(PPh₃)₃ exhibits excellent catalytic ability toward the anti-Markovnikov addition of thiols (ArSH) to alkynes (RC≡CH), which affords the corresponding vinylic sulfides (trans-RCH=CHSAr) regio- and stereoselectively. The reaction may proceed by the formation of hydrorhodium sulfide species (H-[Rh]-SAr) and probably via the subsequent hydrorhodation of alkynes to provide vinylrhodium intermediates (RCH=CH-[Rh]-SAr). In contrast, PdCl₂(PhCN)₂-catalyzed hydrothiolation of aromatic alkynes (ArC≡CH) takes place to give the corresponding Markovnikov adducts (R(ArS)C=CH₂) with excellent regioselectivity, probably via thiopalladation of alkynes by palladium sulfide species (ArS-[Pd]-Cl), which may be formed by ligand-exchange reaction between PdCl₂(PhCN)₂ and ArSH. Furthermore, in the case of alkynes bearing propargylic protons (R'CH₂C≡CH), a sequential addition/isomerization reaction occurs to provide the internal vinylic sulfides (R'CH=C(SAr)CH₃) regioselectively. From the same starting materials (alkyne and thiol), therefore, the regioselectivity of hydrothiolation can be attained simply by changing the catalysts, i.e., RhCl(PPh₃)₃ and PdCl₂(PhCN)₂.

Full text of DOI:10.1021/ja983949i

5108
J. Am. Chem. Soc. 1999, 121, 5108-5114
Highly Regio- and Stereocontrolled Synthesis of Vinyl Sulfides via
Transition-Metal-Catalyzed Hydrothiolation of Alkynes with Thiols
Akiya Ogawa,* Takuma Ikeda, Kouichi Kimura, and Toshikazu Hirao*
Contribution from the Department of Applied Chemistry, Faculty of Engineering, Osaka UniVersity,
Suita, Osaka 565-0871, Japan
ReceiVed NoVember 16, 1998
Abstract: Regio- and stereoselectivity in the hydrothiolation of alkynes with thiols in the presence of a variety
of transition-metal catalysts is investigated in detail. Among the catalysts employed, RhCl(PPh3)3 exhibits
excellent catalytic ability toward the anti-Markovnikov addition of thiols (ArSH) to alkynes (RCtCH), which
affords the corresponding vinylic sulfides (trans-RCHdCHSAr) regio- and stereoselectively. The reaction
may proceed by the formation of hydrorhodium sulfide species (H-[Rh]-SAr) and probably via the subsequent
hydrorhodation of alkynes to provide vinylrhodium intermediates (RCHdCH-[Rh]-SAr). In contrast, PdCl2-
(PhCN)2-catalyzed hydrothiolation of aromatic alkynes (ArCtCH) takes place to give the corresponding
Markovnikov adducts (R(ArS)CdCH2) with excellent regioselectivity, probably via thiopalladation of alkynes
by palladium sulfide species (ArS-[Pd]-Cl), which may be formed by ligand-exchange reaction between
PdCl2(PhCN)2 and ArSH. Furthermore, in the case of alkynes bearing propargylic protons (R′CH2CtCH), a
sequential addition/isomerization reaction occurs to provide the internal vinylic sulfides (R′CHdC(SAr)CH3)
regioselectively. From the same starting materials (alkyne and thiol), therefore, the regioselectivity of
hydrothiolation can be attained simply by changing the catalysts, i.e., RhCl(PPh3)3 and PdCl2(PhCN)2.
Introduction
important synthetic intermediates.3 It is well-known that thiols
add to alkynes under radical conditions to afford anti-Mark-
ovnikov-type vinylic sulfides with excellent regioselectivity,
usually as a stereoisomeric mixture (eq 1).4 In contrast to this,
Although organic thiols have been widely employed as the
sources of ligands for various transition metals,1 the transition-
metal-catalyzed reactions using them as substrates have been
scarcely developed.2 This is partly due to the widespread belief
that organic sulfur compounds often bind strongly to the
catalysts, thus poisoning them and making catalytic reactions
ineffective. The addition of thiols to alkynes is one of the most
straightforward methods of obtaining vinylic sulfides, which are
(1) (a) Linford, L.; Raubenheimer, H. G. In AdVances in Organometallic
Chemistry; Stone, F. G. A., West, R., Eds.; Academic Press: San Diego,
CA, 1991; Vol. 32, p 1. (b) Stiefel, E. I.; Matsumoto, K., Eds. Transition
Metal Sulfur Chemistry: Biological and Industrial Significance; ACS Symp.
Ser. 653; American Chemical Society: Washington, DC, 1996. (c) Rakowski
Dubois, M. Chem. ReV. 1989, 89, 1.
we have recently revealed that the addition of thiols to terminal
alkynes in the presence of a catalytic amount of palladium(II)
acetate (Pd(OAc)2) proceeds with a different regioselectivity
to afford the corresponding Markovnikov adducts in high yields
(eq 1).5
(2) (a) Holmquist, H. E.; Carnahan, J. E. J. Org. Chem. 1960, 25, 2240.
(b) Talley, J. J.; Colley, A. M. J. Organomet. Chem. 1981, 215, C38. (c)
McKervey, M. A.; Ratananukul, P. Tetrahedron Lett. 1982, 23, 2509. (d)
Dzhemilev, U. M.; Kunakova, R. V.; Gaisin, R. L. IzV. Akad. Nauk SSSR,
Ser. Khim. 1984, 11, 2655. (e) Shim, S. C.; Antebi, S.; Alper, H. Tetrahedron
Lett. 1985, 26, 1935. (f) Antebi, S.; Alper, H. Tetrahedron Lett. 1985, 26,
2609. (g) Shim, S. C.; Antebi, S.; Alper, H. J. Org. Chem. 1985, 50, 147.
(h) Antebi, S.; Alper, H. Organometallics 1986, 5, 596. (i) Antebi, S.; Alper,
H. Can. J. Chem. 1986, 64, 2010. (j) Iqbal, J.; Pandey, A.; Shukla, A.;
Srivastava, R. R.; Tripathi, S. Tetrahedron 1990, 46, 6423. (k) Goux, C.;
Lhoste, P.; Sinou, D. Tetrahedron Lett. 1992, 33, 8099. (l) Ogawa, A.;
Sonoda, N. J. Synth. Org. Chem. Jpn. 1993, 51, 815. (m) Ba¨ckvall, J.-E.;
Ericsson, A. J. Org. Chem. 1994, 59, 5850. (n) Ogawa, A.; Takeba, M.;
Kawakami, J.; Ryu, I.; Kambe, N.; Sonoda, N. J. Am. Chem. Soc. 1995,
117, 7564. (o) Ogawa, A.; Kawakami, J.; Sonoda, N.; Hirao, T. J. Org.
Chem. 1996, 61, 4161. (p) Ogawa, A.; Kawakami, J.; Mihara, M.; Ikeda,
T.; Sonoda, N. Hirao, T. J. Am. Chem. Soc. 1997, 119, 12380. (q) Xiao,
W.-J.; Alper, H. J. Org. Chem. 1997, 62, 3422. (r) Xiao, W.-J.; Vasapollo,
G.; Alper, H. J. Org. Chem. 1998, 63, 2609. (s) Ogawa, A.; Kawabe, K.;
Kawakami, J.; Mihara, M.; Hirao, T. Organometallics 1998, 17, 3111.
The mechanistic pathway given in Scheme 1 is proposed, on
the basis of the following facts: (i) the stoichiometric reaction
(3) For the synthetic utility of vinyl sulfides, see, for example: (a) Ager,
D. J. Chem. Soc. ReV. 1982, 11, 493. (b) Takeda, T.; Furukawa, H.; Fujimori,
M.; Suzuki, K.; Fujiwara, T. Bull. Chem. Soc. Jpn. 1984, 57, 1863. (c)
Gro¨bel, B.-T.; Seebach, D. Synthesis 1977, 357. (d) Trost, B. M.; Lavoie,
A. C. J. Am. Chem. Soc. 1983, 105, 5075. (e) Magnus, P.; Quagliato, D. J.
Org. Chem. 1985, 50, 1621. (f) De Lucchi, O.; Pasquato, L. Tetrahedron
1988, 44, 6755. (g) Pettit, G. R.; van Tamelen, E. E. Org. React. 1962, 12,
356. (h) Boar, R. B.; Hawkins, D. W.; McGhie, J. F.; Barton, D. H. R. J.
Chem. Soc., Perkin Trans. 1 1973, 654. (i) Trost, B. M.; Ornstein, P. L.
Tetrahedron Lett. 1981, 22, 3463. (j) Wenkert, E.; Ferreira, T. W. J. Chem.
Soc., Chem. Commun. 1982, 840. (k) Hojo, M.; Tanimoto, S. J. Chem.
Soc., Chem. Commun. 1990, 1284. (l) Hojo, M.; Harada, H.; Yoshizawa,
J.; Hosomi, A. J. Org. Chem. 1993, 58, 6541.
10.1021/ja983949i CCC: $18.00 © 1999 American Chemical Society
Published on Web 05/18/1999

Regio- and Stereocontrolled Synthesis of Vinyl Sulfides
J. Am. Chem. Soc., Vol. 121, No. 22, 1999 5109
Table 1. Transition-Metal-Catalyzed Addition of PhSH to
Scheme 1. Possible Pathway for Pd(OAc)2-Catalyzed
Hydrothiolation
1-Octynea
yield, %b
entry no.
catalyst
Pd(OAc)2
PdCl2(PhCN)2
PdCl2(MeCN)2
Pd(PPh3)4
2a
3a [E/Z]
4a [E/Z]
1c
2
3
85
1
2
trace
66 [56/44]
trace
0
58 [64/36] 23 [51/49]
16 [91/9]
4
17
2
5
Pt(PPh3)2(CH2dCH2) 19 38 [63/37] 17 [50/50]
6d
7
Pt(PPh3)2(CH2dCH2) 41 10 [76/24]
5 [40/60]
16 [76/24]
RhH(CO)(PPh3)3
RhH(CO)(PPh3)3
RhH(CO)(PPh3)3
RhCl(PPh3)3
49
0
8d
9e
10
11f
19 26 [61/39] 14 [89/11]
2
29
0
58 [67/33]
7 [43/57]
50 [100/0]
65 [48/52]
0
0
of Pd(OAc)2 with benzenethiol (2 equiv) provides palladium
sulfide species ([Pd(SPh)2]n) and AcOH (2 equiv); (ii) a catalytic
hydrothiolation of alkynes with PhSH can proceed using the
palladium sulfide species as the catalyst. A possible catalytic
pathway involves the ligand-exchange reaction between Pd-
(OAc)2 and PhSH to generate palladium sulfide species ([Pd-
(SPh)2]n) with concomitant formation of acetic acid, followed
by regioselective thiopalladation of alkynes to give the corre-
sponding vinylic palladium intermediate. The subsequent pro-
tonation of the vinylic palladium species with PhSH provides
the Markovnikov-type vinylic sulfide with regeneration of the
palladium sulfide catalyst. Thus, the radical reaction and the
Pd(OAc)2-catalyzed reaction are complementary to each other
for the regioselective synthesis of vinylic sulfides from the same
starting materials, i.e., alkynes and thiols.
a Reaction conditions: 1-octyne (1 mmol), PhSH (1 mmol), catalyst
(5 mol %), benzene (0.5 mL), 80 °C, 20 h. b Determined by 1H NMR.
c Catalyst (2 mol %), THF (0.5 mL), 40 °C. d Catalyst (3 mol %).
e Catalyst (0.5 mol %). f In the absence of catalysts.
As mentioned already, Pd(OAc)2 effects the Markovnikov
addition of PhSH to 1a (entry 1). On the other hand, some other
divalent palladium complexes, especially PdCl2(PhCN)2, ex-
hibited excellent catalytic activity for the sequential Markovni-
kov addition and double-bond isomerization to afford the
corresponding internal vinylic sulfides (3a) selectively (entries
2 and 3). In contrast, palladium(0) and platinum(0) catalysts
did not indicate the product selectivity at all (entries 4-6). In
the case of the former catalyst, 10-15% of Vic-bis(phenylthio)-
1-octene was also obtained. In the case of the latter catalyst,
the product selectivity was dependent on amounts of the catalyst
employed: the double-bond isomerization of 2a to 3a was
depressed by decreasing the catalyst (entry 6). As reported
previously,2n RhH(CO)(PPh3)3 is an excellent catalyst for the
regioselective thioformylation of alkynes with benzenethiol in
the presence of carbon monoxide (eq 3). In contrast to our
In this paper, we wish to report that, when PdCl2(PhCN)2 is
used as a catalyst, a novel Markovnikov addition and double-
bond isomerization reaction of benzenethiol with terminal
alkynes is found to take place sequentially, which provides a
useful tool for preparing internal vinylic sulfides (3) (eq 2). More
interestingly, switching the catalyst simply from Pd(OAc)2 to
RhCl(PPh3)3 leads to a sharp reversal of regioselectivity in the
addition of PhSH to alkynes, providing anti-Markovnikov-type
vinylic sulfides (4) with the trans configuration (eq 2).
expectation that the catalyst may exhibit the excellent regiose-
lectivity in the hydrothiolation, however, the addition of PhSH
to 1a in the presence of this rhodium catalyst provided both
Markovnikov and anti-Markovnikov adducts (2a, 3a, and 4a,
respectively), where the formation ratio of 2a vs 3a depended
on the amounts of the catalyst employed (entries 7-9).
Similarly, Wilkinson catalyst (RhCl(PPh3)3) also gave rise
to both Markovnikov and anti-Markovnikov adducts (2a and
4a), but the fact that the stereochemistry of 4a was only E is
noteworthy (entry 10). In the absence of catalyst, the reaction
of PhSH with 1-octyne in refluxing benzene afforded the
corresponding anti-Markovnikov adduct as a stereoisomeric
mixture (entry 11). In contrast to this, the use of PdCl2(PhCN)2
or Pd(OAc)2 led to a sharp reversal of regioselectivity of the
hydrothiolation, whereas the RhCl(PPh3)3-catalyzed hydrothi-
olation proceeded with excellent stereoselectivity.
Results and Discussion
Influence of Catalysts on the Hydrothiolation of 1-Octyne
with Benzenethiol. The reaction of benzenethiol with 1-octyne
(1a) was examined in the presence of several transition-metal
catalysts, and the results are summarized in Table 1.
(4) (a) Peach, M. E. In The Chemistry of the Thiol Group; Patai, S.,
Ed.; Wiley: London, 1974; Vol. 2. (b) Ichinose, Y.; Wakamatsu, K.; Nozaki,
K.; Birbaum, J.-L.; Oshima, K.; Utimoto, K. Chem. Lett. 1987, 1647. (c)
Benati, L.; Capella, L.; Montevecchi, P. C.; Spagnolo, P. J. Chem. Soc.,
Perkin Trans. 1 1995, 1035. (d) Griesbaum, K. Angew. Chem., Int. Ed.
Engl. 1970, 9, 273 and references therein.
(5) (a) Kuniyasu, H.; Ogawa, A.; Sato, K.; Ryu, I.; Kambe, N.; Sonoda,
N. J. Am. Chem. Soc. 1992, 114, 5902. Also, see: (b) Kuniyasu, H.; Ogawa,
A.; Sato, K.; Ryu, I.; Sonoda, N. Tetrahedron Lett. 1992, 33, 5525. (c)
Ogawa, A.; Kudo, A.; Hirao. T. Tetrahedron Lett. 1998, 39, 5213, and refs
2l,m,o.
PdCl2(PhCN)2-Catalyzed Sequential Addition/Isomeriza-
tion Reaction of Benzenethiol with Terminal Alkynes. Table

5110 J. Am. Chem. Soc., Vol. 121, No. 22, 1999
Ogawa et al.
Table 2. PdCl2(PhCN)2-Catalyzed Sequential Addition/
Scheme 2. Possible Pathway for PdCl2(PhCN)2-Catalyzed
Hydrothiolation
Isomerization Reactionsa
the elemental analysis of which suggests the formation of the
palladium sulfide complex A, as depicted in eq 5 (see also the
Experimental Section). The reaction of benzenethiol with
a Reactionconditions: alkyne(1mmol),PhSH(1mmol),PdCl2(PhCN)2
(5 mol %), benzene (0.5 mL), 80 °C, 20 h. b E/Z ratio was determined
1
by H NMR.
2 represents the sequential addition/isomerization reactions of
terminal alkynes in the presence of PdCl2(PhCN)2. 5-Methyl-
1-hexyne (1b) and benzylacetylene (1c) were selectively
converted to 2-(phenylthio)-5-methyl-2-hexene (3b) and 2-(phe-
nylthio)-2-methylstyrene (3c), respectively, in good yields
(entries 2 and 3). Similar conditions can be employed with an
alkyne (1d) bearing a cyano group, giving the corresponding
internal vinylic sulfide (3d) regioselectively (entry 4). However,
hydrothiolation of propargyldimethylamine (1e) provided only
Markovnikov adduct (2e) regioselectively in 69% yield; this
indicates that the presence of a basic amino group inhibits the
double-bond isomerization entirely (entry 5). On the other hand,
alkynes bearing no propargylic protons, such as phenylacetylene
(1f), underwent regioselective hydrothiolation to provide Mark-
ovnikov adduct (2f) in good yield (entry 6). In the case of an
inner alkyne (1g), hydrothiolation proceeded to give three
regioisomeric adducts (2g, 3g, and 4g), as shown in eq 4.
1-octyne (1a) in the presence of the complex A as a catalyst
afforded the corresponding addition/isomerization product 3a
in 42% yield (eq 6). In addition, treatment of the Markovnikov
adduct 2a in the presence of a catalytic amount of complex A
resulted in the double-bond isomerization to give 3a in almost
quantitative yield (eq 7).6 These observations suggest that the
complex A is an excellent catalyst for the double-bond isomer-
ization reaction and also exhibits a moderate catalytic activity
toward the Markovnikov addition reaction of thiols to alkynes.
Scheme 2 illustrates a possible reaction pathway for the PdCl2-
(PhCN)2-catalyzed hydrothiolation of alkynes, which includes
the following: (i) the ligand-exchange reaction of PdCl2(PhCN)2
with PhSH forms Pd(SPh)ClLn, which adds to alkyne 1,
providing vinylic palladium intermediate B; (ii) protonation of
B with PhSH leads to the Markovnikov type adduct C; (iii)
double-bond isomerization of C to 3 takes place via cationic
intermediate D6 and allylpalladium intermediate E.
RhCl(PPh3)3-Catalyzed anti-Markovnikov Addition of
Thiols to Alkynes. As mentioned in Table 1, the RhCl(PPh3)3-
To get some information about this sequential addition/
isomerization reaction, the stoichiometric reaction of PdCl2-
(PhCN)2 with 2 equiv of PhSH in benzene at room temperature
was conducted. The reaction provided a reddish brown solid,
(6) (a) Sen, A.; Lai, T.-W. Inorg. Chem. 1981, 20, 4036. (b) Sen, A.;
Lai, T.-W. Inorg. Chem. 1984, 23, 3257.

Regio- and Stereocontrolled Synthesis of Vinyl Sulfides
J. Am. Chem. Soc., Vol. 121, No. 22, 1999 5111
Table 3. RhCl(PPh3)3-Catalyzed Regio- and Stereoselective
Table 4. RhCl(PPh3)3-Catalyzed Regio- and Stereoselective
Addition of PhSH to 1-Octynea
Addition of PhSH to Acetylenesa
yield, %b
temp,
°C (amt, mol %)
additive
2a
3a
4a
[E/Z]
entry no. solvent
1
PhH
PhH
PhH
PhCH3
THF
PhCF3
CH2Cl2
(CH2Cl)2
DMF
CH3CN
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
80
80
40
110
67
40
40
40
100
40
78
25
29
15
19
17
9
0
11
0
4
15
7
0
4
16
23
9
3
4
0
0
0
50 [100/0]
65 [99/1]
54 [100/0]
20 [98/2]
2c
3
4
5
6
7
8
9
10
11
12d
13e
14
15
16
17
18f
19
20g
60 [100/0]
49 [100/0]
76 [100/0]
58 [100/0]
39 [100/0]
40 [96/4]
58 [100/0]
69 [100/0]
80 [100/0]
53 [100/0]
60 [100/0]
63 [100/0]
31 [100/0]
69 [100/0]
73 [100/0]
5
22
11
0
2
0
0
0
36
34
25
25 PPh3 (30)
25 PPh3 (10)
25 P(tol-o)3 (30) 21
25 PBun3 (30)
19
26
0
0
0
0
25
25 galvinoxyl (3)
25
no reacn
a Reaction conditions: 1-octyne (1 mmol), PhSH (1.1 mmol),
1
RhCl(PPh3)3 (5 mol %), solvent (0.5 mL), 20 h. b Determined by H
NMR. c Catalyst (10 mol %). d (PhS)2 was formed as a byproduct.
e PhSH was added dropwise. f o-CH3-C6H4SH was used in place of
PhSH. g In the absence of RhCl(PPh3)3 catalyst.
catalyzed hydrothiolation of 1-octyne (1a) with PhSH provided
(E)-1-(phenylthio)-1-octene (4a) along with its regioisomer (2a)
(see Table 1, entry 10). Thus, we next investigated in detail the
RhCl(PPh3)3-catalyzed hydrothiolation under various reaction
conditions (Table 3). The influence of the solvents on the RhCl-
(PPh3)3-catalyzed hydrothiolation was examined (entries 1-11),
and, among the solvents employed (PhH, PhMe, THF, BTF,7
CH2Cl2, (CH2Cl)2, DMF, MeCN, EtOH), the use of EtOH
realized the highest product selectivity of (E)-4a (entry 11).
When the hydrothiolation was conducted in EtOH at a lower
temperature, a better selectivity of (E)-4a was observed (entry
12). In this reaction, however, (PhS)2 (ca. 20%) was formed as
a byproduct. The dropwise addition of PhSH is expected to
depress the formation of (PhS)2. Thus, the best result was
obtained when a slight excess of PhSH was added dropwise at
25 °C over 1 h to the solution of 1-octyne and RhCl(PPh3)3 (5
mol %) in EtOH (entry 13). Moreover, the influence of the
bulkiness of ligands and thiols on the selectivity of the
hydrothiolation was investigated. Although the addition of
phosphines to the catalytic system decreased the selectivity of
the hydrothiolation (entries 14 and 15), the use of more bulky
phosphine did not improve the regioselectivity (entries 16 and
17). Similarly, the use of o-methylbenzenethiol in place of PhSH
also decreased the selectivity (entry 18). To rule out the
possibility that a radical mechanism contributes to this anti-
Markovnikov addition process, the rhodium-catalyzed reaction
of PhSH to alkynes was examined in the presence of a radical
inhibitor such as galvinoxyl (entry 19). The reaction proceeded
smoothly to provide the anti-Markovnikov adduct regio- and
stereoselectively. In the absence of the rhodium catalyst, the
reaction of PhSH with alkynes in EtOH resulted in only recovery
of the starting materials (entry 20). These observations clearly
indicate that the present anti-Markovnikov addition process
proceeds as a catalytic reaction of RhCl(PPh3)3.
a Reaction conditions: alkyne (1 mmol), PhSH (1.1 mmol), RhCl(P-
Ph3)3 (1-3 mol %), EtOH (1 mL), 20 h. b Isolated yield based on the
thiol used. c Thiol was added dropwise over 1 h. d p-MeO-C6H4SH was
used. e p-Cl-C6H4SH was used.
Table 4 represents the results of the RhCl(PPh3)3-catalyzed
addition of ArSH to a series of alkynes. The procedure can be
applied to both aromatic and aliphatic alkynes. Similarly,
arenethiols bearing p-methoxy and p-chloro groups add to
alkynes regio- and stereoselectively (entries 5 and 6). In contrast,
the hydrothiolation with alkanethiols such as cyclohexanethiol
did not proceed at all under the same conditions, and most of
the starting materials were recovered unchanged. Inner alkynes
such as 1n and 1o underwent stereoselective hydrothiolation,
and in particular, excellent regioselectivity was also observed
in the hydrothiolation of 1o (entries 11 and 12). Functionalities
such as fluoro, chloro, hydroxy, methoxy, and olefinic groups
tolerate the reaction conditions (entries 3, 5, 6, and 8-10). In
all cases listed in Table 4, the addition proceeded with excellent
regio- and stereoselectivity to provide only the E isomer of the
anti-Markovnikov adduct 4.
(7) Ogawa, A.; Curran, D. P. J. Org. Chem. 1997, 62, 450.

5112 J. Am. Chem. Soc., Vol. 121, No. 22, 1999
Ogawa et al.
Scheme 3. Possible Pathway for RhCl(PPh3)3-Catalyzed
Hydrothiolation
place by employing PdCl2(PhCN)2 as a catalyst. From the same
starting materials (alkyne and thiol), therefore, isomeric vinylic
sulfides can be synthesized with excellent selectivity simply by
switching the catalysts, i.e., PdCl2(PhCN)2 and RhCl(PPh3)3.
This paper again demonstrates the utility of transition-metal
catalysts in the synthetic reactions of sulfur compounds.
Experimental Section
General Methods. 1H NMR spectra were recorded on Varian
MERCURY 300 (300 MHz), JEOL JNM-AL400 (400 MHz), and JEOL
JNM-GSX-400 (400 MHz) spectrometers using CDCl3 as the solvent
with Me4Si as the internal standard. 13C NMR spectra were taken on
Varian MERCURY 300 (75 MHz) and JEOL JNM-AL400 (100 MHz)
spectrometers using CDCl3 as the solvent. Chemical shifts in 13C NMR
spectra were measured relative to CDCl3 and converted to δMe Si values
4
by using δCDCl 76.9 ppm. IR spectra were determined on a Perkin-
3
Elmer Model 1600 spectrometer. Melting points were determined on a
Yanagimoto micro melting point apparatus. Mass spectra were obtained
on a JEOL JMS-DX303 in the analytical section of our department.
Elemental analyses were also performed there. The number-average
molecular weights (Mn) and weight-average molecular weights (Mw)
of the complex A (obtained by the reaction of PdCl2(PhCN)2 with PhSH
(2 equiv)) were determined using gel permeation chromatography
(GPC). The GPC equipment (HLC-8020 system, Tosoh, Tokyo, Japan)
consisted of an RI detector and Tosoh TSKgel R3000 and R5000.
Calibration was carried out using narrow weight distribution PEG
To explore the reaction pathway for this RhCl(PPh3)3-
catalyzed hydrothiolation, the stoichiometric reaction of RhCl-
(PPh3)3 with benzenethiol was examined. The equimolar reaction
of RhCl(PPh3)3 with PhSH at 20 °C in dichloromethane under
an argon atmosphere afforded a yellow solid, which could be
identified unambiguously as trans-HRhCl(SPh)(PPh3)2 (F),
reported in the literature8 (eq 8). The catalytic reaction of
1-dodecyne (1j) with benzenethiol in the presence of 3 mol %
of complex F afforded the anti-Markovnikov adduct 4j in good
yield (eq 9).
standards (Tosoh), ranging from ca. 2 × 102 to 9.9 × 105 g mol-1
.
The eluent used was N,N-dimethylformamide (DMF; HPLC grade), at
a flow rate of 0.5 mL min-1
.
All materials were obtained from commercial suppliers and purified
by distillation or recrystallization.
General Procedure for the PdCl2(PhCN)2-Catalyzed Hydrothi-
olation of Alkynes with Thiols. In a 20 mL two-necked glass flask
equipped with a condenser and a magnetic stirring bar under an argon
atmosphere were placed PdCl2(PhCN)2 (5 mol %, 0.0192 g), benzene
(0.5 mL), alkyne (1.0 mmol: 1a, 0.110 g, 0.148 mL; 1b, 0.0962 g,
0.132 mL; 1c, 0.116 g, 0.124 mL; 1d, 0.0931 g, 0.105 mL; 1e, 0.0831
g, 0.105 mL; 1f, 0.102 g, 0.110 mL; 1g, 0.144 g, 0.155 mL), and
benzenethiol (1.0 mmol, 0.110 g, 0.103 mL). The reaction was
conducted with magnetic stirring for 20 h at 80 °C. After the reaction
was complete, the resulting mixture was filtered through Celite and
concentrated in vacuo. Purification was performed by a recycling
preparative HPLC (Japan Analytical Industry Co. Ltd., Model LC-908),
equipped with JAIGEL-1H and -2H columns (GPC, using CHCl3 as
an eluent) or by preparative TLC (silica gel, hexane as an eluent).
To gain further insight into the mechanistic pathway, the
RhCl(PPh3)3-catalyzed hydrothiolation of 1-dodecyne (1j) with
1
2-(Phenylthio)-2-octene (3a): yellow liquid. H NMR (300 MHz,
1
PhSH was monitored by H NMR spectra. The reaction of
CDCl3): (E isomer) δ 0.89 (t, J ) 6.6 Hz, 3 H), 1.27-1.53 (m, 6 H),
1.90 (s, 3 H), 2.31 (q, J ) 6.8 Hz, 2 H), 5.83 (t, J ) 6.9 Hz, 1 H),
7.16-7.35 (m, 5 H); (Z isomer) δ 0.90 (t, J ) 6.9 Hz, 3 H), 1.27-
1.53 (m, 6 H), 1.87 (s, 3 H), 2.12 (q, J ) 7.2 Hz, 2 H), 5.90 (t, J ) 7.2
Hz, 1 H), 7.16-7.35 (m, 5 H). 13C NMR (75 MHz, CDCl3): (E isomer)
δ 14.2, 22.6, 24.5, 29.2, 30.0, 31.6, 126.0, 128.3, 128.7, 129.9, 135.0,
136.0; (Z isomer) δ 14.2, 18.2, 22.6, 29.0, 29.4, 31.6, 126.1, 128.0,
128.7, 129.8, 135.5, 136.75. IR (NaCl): 3058, 2922, 2854, 1584, 1475,
1439, 741, 692 cm-1. MS (EI): m/z 220 (M+, 82.0). Anal. Calcd for
C14H20S: C, 76.30; H, 9.15; S, 14.55. Found: C, 76.05; H, 9.09; S,
14.33.
complex F with an equimolar amount of 1j at room temperature
led to the disappearance of both Rh-H (δ -16.4) and acetylenic
H, and instead, a new doublet peak appeared at δ 5.1 (probably
as the vinylic proton). The new peak did not disappear after
standing for 20 h at room temperature, but the addition of PhSH
(1 equiv) to the solution led to the formation of vinylic sulfide
(4j) after standing for 6 h. Thus, a possible catalytic cycle for
this hydrothiolation of alkynes is shown in Scheme 3. Formation
of H-[Rh]-SPh (F) occurred via the oxidative addition of
PhSH to RhClLn, followed by the stereoselective insertion of
alkynes into the Rh-H bond to form the trans-vinylrhodium
intermediate G. The subsequent reductive elimination of the
anti-Markovnikov adduct, in the presence of excess PhSH,
regenerates the catalyst F.
In conclusion, we have developed a highly selective anti-
Markovnikov addition of benzenethiol to alkynes catalyzed by
RhCl(PPh3)3, which is complementary to the previously reported
Pd(OAc)2-catalyzed Markovnikov addition of benzenethiol to
acetylenes. Also, a useful sequential addition/isomerization
reaction of benzenethiol with terminal alkynes is found to take
1
2-(Phenylthio)-5-methyl-2-hexene (3b): yellow liquid. H NMR
(300 MHz, CDCl3): (E isomer) δ 0.93 (t, J ) 6.6 Hz, 6 H), 1.70 (septet,
J ) 6.9 Hz, 1 H), 1.92 (q like, J ) 1.5 Hz, 3 H), 2.23 (tq, J ) 1.2, 7.2
Hz, 2 H), 5.84 (tq, J ) 1.5, 6.9 Hz, 1 H), 7.16-7.33 (m, 5 H); (Z
isomer) δ 0.93 (t, J ) 6.6 Hz, 6 H), 1.70 (septet, J ) 6.9 Hz, 1 H),
1.87 (quint like, J ) 0.6 Hz, 3 H), 2.02 (t, J ) 7.1 Hz, 2 H), 5.90 (tq,
J ) 1.5, 7.2 Hz, 1 H), 7.16-7.33 (m, 5 H). 13C NMR (75 MHz,
CDCl3): (E isomer) δ 22.5, 24.6, 28.8, 39.1, 126.0, 128.7, 129.1, 130.0,
134.7, 135.0; (Z isomer) δ 18.3, 22.5, 28.7, 38.5, 126.2, 128.8, 129.9,
135.3, 135.4. IR (NaCl) 3070, 2954, 1583, 1476, 1438, 1382, 1067,
1025, 741, 692 cm-1. MS (EI): m/z 206 (M+, 72.4). Anal. Calcd for
C13H18S: C, 75.67; H, 8.79; S, 15.53. Found: C, 75.55; H, 8.80; S,
15.36.
(8) Singer, H.; Wilkinson. G. J. Chem. Soc. A 1968, 2516.

Regio- and Stereocontrolled Synthesis of Vinyl Sulfides
J. Am. Chem. Soc., Vol. 121, No. 22, 1999 5113
2-(Phenylthio)-2-methylstyrene (3c): yellow liquid. 1H NMR (300
MHz, CDCl3): (E isomer) δ 2.13 (s, 3 H), 6.68 (s, 1 H), 7.19-7.56
(m, 10 H); (Z isomer) δ 2.03 (s, 3 H), 6.71 (s, 1 H), 7.19-7.56 (m, 10
H). 13C NMR (75 MHz, CDCl3): (E isomer) δ 19.7, 126.7, 127.3, 128.2,
128.6, 129.0, 130.7, 132.0, 133.7, 133.8, 137.0; (Z isomer) δ 25.8,
126.9, 127.1, 127.9, 128.8, 129.0, 130.8, 133.7, 136.7. IR (NaCl): 3056,
2914, 1582, 1475, 1439, 1099, 1025, 746, 693 cm-1. MS (EI): m/z
226 (M+, 100.0). Anal. Calcd for C15H14S: C, 79.60; H, 6.23; S, 14.17.
Found: C, 79.32; H, 6.13; S, 14.11.
m/z 220 (M+, 91.0). Anal. Calcd for C14H20S: C, 76.30; H, 9.15; S,
14.55. Found: C, 76.29; H, 9.10; S, 14.44.
(E)-2-(Phenylthio)styrene (4f): colorless liquid. 1H NMR (300
MHz, CDCl3): δ 6.73 (d, J ) 15.3 Hz, 1 H), 6.86 (d, J ) 15.3 Hz, 1
H), 7.17-7.44 (m, 10 H). 13C NMR (75 MHz, CDCl3): δ 123.3, 125.9,
126.8, 127.5, 128.6, 129.0, 129.7, 131.7, 135.1, 136.4;. IR (NaCl):
3059, 3030, 1583, 1479, 1442, 1086, 946, 742, 693 cm-1. MS (EI):
m/z 212 (M+, 100.0). Anal. Calcd for C14H12S: C, 79.20; H, 5.70; S,
15.10. Found: C, 79.21; H, 5.74; S, 15.25.
1
2-(Phenylthio)-5-cyano-2-pentene (3d): yellow liquid. H NMR
(E)-2-(Phenylthio)-p-methylstyrene (4h): white solid; mp 46.2-
1
(400 MHz, CDCl3): (E isomer) δ 1.92 (s, 3 H), 2.41 (t, J ) 6.4 Hz, 2
H), 2.47 (q, J ) 6.8 Hz, 2 H), 5.63 (t, J ) 7.6 Hz, 1 H), 7.24-7.38
(m, 5 H); (Z isomer) δ 1.92 (s, 3 H), 2.44 (t, J ) 7.2 Hz, 2 H), 2.68
(q, J ) 6.8 Hz, 2 H), 5.80 (t, J ) 6.8 Hz, 1 H), 7.24-7.43 (m, 5 H).
13C NMR (100 MHz, CDCl3): (E isomer) δ 17.4, 18.1, 25.2, 118.9,
126.9, 127.2, 128.9, 131.6, 133.3, 134.2; (Z isomer) δ 17.4, 24.4, 25.7,
119.1, 126.8, 128.9, 129.1, 130.9, 133.2, 133.7. IR (NaCl): 3060, 2920,
2246, 1582, 1476, 1437, 1022, 747, 695 cm-1. MS (EI): m/z 203 (M+,
100.0). Anal. Calcd for C12H13NS: C, 70.90; H, 6.45; N, 6.89; S, 15.77.
Found: C, 70.62; H, 6.36; N, 6.93; S, 15.59.
47.0 °C. H NMR (300 MHz, CDCl3): δ 2.38 (s, 3 H), 6.76 (d, J )
15.3 Hz, 1 H), 6.86 (d, J ) 15.3 Hz, 1 H), 7.16 (d, J ) 8.4 Hz, 2 H),
7.27-7.45 (m, 7 H). 13C NMR (75 MHz, CDCl3): δ 21.3, 121.8, 125.9,
126.7, 129.0, 129.3, 129.4, 132.3, 133.7, 135.5, 137.5. IR (KBr): 3018,
1580, 1509, 1477, 1436, 958, 790, 734, 689 cm-1. MS (EI): m/z 226
(M+, 100.0). Anal. Calcd for C15H14S: C, 79.60; H, 6.23; S, 14.16.
Found: C, 79.41; H, 5.93; S, 14.11.
(E)-2-(Phenylthio)-p-fluorostyrene (4i): colorless liquid. 1H NMR
(300 MHz, CDCl3): δ 6.73 (d, J ) 15.3 Hz, 1 H), 6.84 (d, J ) 15.3
Hz, 1 H), 7.05 (t like, J ) 8.7 Hz, 2 H), 7.27-7.47 (m, 7 H). 13C
NMR (75 MHz, CDCl3): δ 115.5 (d, JC-F ) 21.6 Hz), 123.0, 126.9,
127.4 (d, JC-F ) 8.0 Hz), 129.1, 129.7, 130.5, 132.6, 134.9, 162.0 (d,
JC-F ) 255.0 Hz). IR (NaCl): 3062, 1601, 1580, 1507, 1478, 1229,
1158, 949, 840, 741, 691 cm-1. MS (EI): m/z 230 (M+, 100.0). Anal.
Calcd for C14H11FS: C, 73.01; H, 4.81. Found: C, 72.79; H, 4.86.
(E)-1-(Phenylthio)-1-dodecene (4j): colorless liquid. 1H NMR (300
MHz, CDCl3): δ 0.88 (t, J ) 6.6 Hz, 3 H), 1.20-1.39 (m, 14 H), 1.40
(br quint, J ) 6.9 Hz, 2 H), 2.15 (t, J ) 6.6 Hz, 2 H), 6.00 (td, J )
6.6, 15.0 Hz, 1 H), 6.13 (td, J ) 0.9, 15.3 Hz, 1 H), 7.16-7.33 (m, 5
H). 13C NMR (75 MHz, CDCl3): δ 14.3, 22.8, 29.1, 29.2, 29.4, 29.5,
29.7, 32.0, 33.2, 120.5, 125.9, 128.2, 128.8, 136.6, 137.8. IR (NaCl):
Stoichiometric Reaction of PdCl2(PhCN)2 with PhSH. In a 20
mL two-necked glass flask with a magnetic stirring bar under an argon
atmosphere were placed PdCl2(PhCN)2 (0.1 mmol, 0.0384 g) and
benzene (1 mL). Benzenethiol (0.2 mmol, 0.0220 g, 0.0205 mL) was
added to the solution at room temperature, and the resulting mixture
was stirred for 1 h. The resulting reddish brown precipitates were
separated by filtration. After removal of the solvent, the 1H NMR
spectrum of the filtrate was measured, which indicated the formation
of 2 equiv of PhCN. The reddish brown precipitates were rinsed with
benzene several times and then dried under reduced pressure to yield
the complex A almost quantitatively. Complex A (reddish brown
solid): mp >300 °C. IR (KBr): 3049, 1573, 1472, 1435, 1297, 1064,
1021, 998, 734, 682 cm-1. Anal. Calcd for [PdCl(SPh)(PhSH)]: C,
39.90; H, 3.07. Found: C, 39.85; H, 2.82. Complex A was insoluble
in most organic solvents such as benzene, toluene, Et2O, THF, CH2-
Cl2, CHCl3, MeCN, acetone, DMSO, MeOH, EtOH, etc. Although A
was slightly soluble in DMF (ca. 3 mM), the concentration was too
dilute to measure its NMR spectra using d6-DMF as a solvent. Thus,
the 1H and 13C NMR spectra of the solid state form of A were measured
(see the Supporting Information). Mass spectral analysis of A was
unsuccessful because the appropriate matrix could not be found, due
to the insolubility of A in most organic solvents. By using a dilute
solution of A in DMF, however, its molecular weight could be assumed
by using GPC (see General Methods). The number-average molecular
weight (Mn) was 409 (Mw/Mn ) 1.21), which indicates the possibility
that A may be monomeric or dimeric but does not have a polymeric
(or oligomeric) structure.
3082, 2925, 2853, 1584, 1478, 1439, 1090, 1025, 949, 738, 690 cm-1
.
MS (EI): m/z ) 276 (M+, 100.0). Anal. Calcd for C18H28S: C, 78.20;
H, 10.21; S, 11.59. Found: C, 78.23; H, 10.21; S, 11.31.
(E)-1-(p-(Methoxyphenyl)thio)-1-dodecene (4j′): colorless liquid.
1H NMR (300 MHz, CDCl3):δ 0.88 (t, J ) 7.2 Hz, 3 H), 1.24-1.44
(m, 16 H), 2.10 (q, J ) 7.2 Hz, 2 H), 3.79 (s, 3 H), 5.80 (dt, J ) 14.7,
7.2 Hz, 1 H), 6.06 (dt, J ) 15.0, 1.2 Hz, 1 H), 6.86 (d, J ) 9.0 Hz, 2
H), 7.30 (d, J ) 9.0 Hz, 2 H). 13C NMR (75 MHz, CDCl3): δ 14.3,
22.8, 29.2, 29.4, 29.5, 29.7, 32.0, 33.1, 55.4, 114.3, 114.6, 122.6, 131.8,
134.5, 158.7. IR (NaCl): 3047, 2927, 2853, 1593, 1493, 1462, 1287,
1245, 1176, 1101, 946, 825, 722, 639 cm-1. MS (EI): m/z 306 (M+,
100.0). Anal. Calcd for C19H30OS: C, 74.46; H, 9.87; S, 10.46.
Found: C, 74.31; H, 9.64; S, 10.61.
(E)-1-(p-(Chlorophenyl)thio)-1-dodecene (4j′′): colorless liquid.
1H NMR (300 MHz, CDCl3): δ 0.88 (t, J ) 6.0 Hz, 3 H), 1.21-1.37
(m, 14 H), 1.43 (br quint, J ) 6.9 Hz, 2 H), 2.16 (dt, J ) 7.2, 5.7 Hz,
2 H), 6.01 (dt, J ) 6.3, 14.7 Hz, 1 H), 6.08 (d, J ) 14.7 Hz, 1 H),
7.18-7.27 (m, 4 H). 13C NMR (75 MHz, CDCl3): δ 14.2, 22.8, 29.0,
29.2, 29.4, 29.5, 29.6, 29.7, 32.0, 33.2, 119.9, 128.9, 129.4, 129.6, 131.0,
138.8. IR (NaCl): 2924, 2852, 1475, 1094, 1012, 949, 814 cm-1. MS
(EI): m/z 310 (M+, 100.0). Anal. Calcd for C18H27ClS: C, 69.53; H,
8.75. Found: C, 69.34; H, 8.59.
(E)-1-(Phenylthio)-5-methyl-1-hexene (4b): colorless liquid. 1H
NMR (300 MHz, CDCl3): δ 0.90 (d, J ) 8.4 Hz, 6 H), 1.32 (dt, J )
7.0, 8.7 Hz, 2 H), 1.59 (septet, J ) 6.6 Hz, 1 H), 2.17 (ddt, J ) 7.8,
6.6, 1.2 Hz, 2 H), 5.99 (dt, J ) 6.6, 15.0 Hz, 1 H), 6.14 (dt, J ) 1.2,
15.0 Hz, 1 H), 7.15-7.33 (m, 5 H). 13C NMR (75 MHz, CDCl3): δ
22.5, 27.6, 31.1, 38.2, 120.3, 125.9, 128.2, 128.8, 136.6, 137.9. IR
(NaCl): 3026, 2955, 2868, 1584, 1478, 1439, 1384, 1368, 1090, 1025,
946, 819, 738, 690 cm-1. MS (EI): m/z 206 (M+, 100.0). Anal. Calcd
for C13H18S: C, 75.67; H, 8.79; S, 15.53. Found: C, 75.29; H, 8.78;
S, 15.09.
(E)-1-(Phenylthio)-5-chloro-1-pentene (4l): colorless liquid. 1H
NMR (300 MHz, CDCl3): δ 1.91 (quint, J ) 6.6 Hz, 2 H), 2.34 (ddt,
J ) 0.9, 6.9, 7.2 Hz, 2 H), 3.57 (t, J ) 6.3 Hz, 2 H), 5.90 (dt, J ) 7.2,
15.0 Hz, 1 H), 6.23 (dt, J ) 1.2, 15.0 Hz, 1 H), 7.18-7.34 (m, 5 H).
13C NMR (75 MHz, CDCl3): δ 30.2, 31.8, 44.2, 123.0, 126.3, 130.6,
131.9, 133.9, 135.8. IR (NaCl): 3020, 2958, 1716, 1583, 1478, 1440,
950, 711, 691 cm-1. MS (EI): m/z 212 (M+, 84.0). Anal. Calcd for
C11H13ClS: C, 62.11; H, 6.16. Found: C, 62.32; H, 6.11.
General Procedure for the RhCl(PPh3)3-Catalyzed Hydrothiola-
tion of Alkynes with Thiols. In a 20 mL two-necked glass flask with
a magnetic stirring bar under an argon atmosphere were placed RhCl-
(PPh3)3 (3 mol %, 0.0278 g), EtOH (1 mL), and alkyne (1.0 mmol:
1a, 0.110 g, 0.148 mL; 1b, 0.0962 g, 0.132 mL; 1f, 0.102 g, 0.110
mL; 1h, 0.116 g, 0.123 mL; 1i, 0.120 g, 0.115 mL; 1j, 0.163 g, 0.214
mL; 1k, 0.0841 g, 0.0931 mL; 1l, 0.103 g, 0.106 mL; 1m, 0.106 g,
0.118 mL; 1n, 0.110 g, 0.148 mL; 1o, 0.116 g, 0.125 mL), and then
thiol (1.1 mmol, neat: PhSH, 0.121 g, 0.113 mL; p-MeOC6H4SH, 0.154
g, 0.135 mL; p-ClC6H4SH, 0.159 g; o-MeC6H4SH, 0.137 g, 0.130 mL)
was added dropwise to the solution over 1 h at room temperature (25
°C). The reaction was continued with magnetic stirring for 20 h at room
temperature. After the reaction was complete, the solvent was removed
in vacuo. Purification was performed by a recycling preparative HPLC
(Japan Analytical Industry Co. Ltd., Model LC-908), equipped with
JAIGEL-1H and -2H columns (GPC, using CHCl3 as an eluent) or by
preparative TLC (silica gel, hexane as an eluent).
1
(E)-1-(Phenylthio)-1-octene (4a): colorless liquid. H NMR (300
MHz, CDCl3): δ 0.89 (t, J ) 6.9 Hz, 3 H), 1.20-1.37 (m, 6 H), 1.42
(br quint, J ) 7.5 Hz, 2 H), 2.15 (dt, J ) 6.6, 7.5 Hz, 2 H), 6.00 (dt,
J ) 6.6, 15.0 Hz, 1 H), 6.13 (dt, J ) 1.2, 14.7 Hz, 1 H), 7.14-7.35
(m, 5 H). 13C NMR (75 MHz, CDCl3): δ 14.2, 22.7, 28.9, 29.1, 31.7,
33.2, 120.5, 125.9, 126.0, 128.3, 128.8, 137.8. IR (NaCl): 3059, 2927,
2854, 1583, 1478, 1439, 1090, 1025, 949, 738, 690 cm-1. MS (EI):

5114 J. Am. Chem. Soc., Vol. 121, No. 22, 1999
Ogawa et al.
(E)-1-(Phenylthio)-2-(1′-cyclohexenyl)ethene (4m): yellow liquid.
1H NMR (300 MHz, CDCl3): δ 1.52-1.75 (m, 4 H), 2.15 (m, 4 H),
5.76 (br t, J ) 3.3 Hz, 1 H), 6.21 (d, J ) 15.6 Hz, 1 H), 6.46 (d, J )
15.3 Hz, 1 H), 7.19-7.37 (m, 5 H). 13C NMR (75 MHz, CDCl3): δ
22.4, 22.5, 24.6, 26.0, 117.6, 126.2, 128.8, 128.9, 130.1, 134.9, 137.4.
IR (NaCl): 3024, 2929, 2860, 1673, 1580, 1476, 1439, 950, 741, 694
cm-1. MS (EI): m/z 216 (M+, 100.0). Anal. Calcd for C14H16S: C,
77.73; H, 7.45; S, 14.82. Found: C, 77.21; H, 7.27; S, 14.26.
2864, 1614, 1582, 1475, 1439, 1376, 1099, 1024, 917, 745, 693 cm-1
.
MS (EI): m/z 226 (M+, 100.0). Anal. Calcd for C15H14S: C, 79.60; H,
6.23; S, 14.17. Found: C, 79.33; H, 6.02; S, 14.17.
Acknowledgment. This research was supported in part by
a Grant-in-Aid for Scientific Research on Priority Areas (No.
09239102) from the Ministry of Education, Science and Culture
of Japan. We are grateful to Dr. Koh Kidena for help in
1
(E)-4-(Phenylthio)-4-octene (4n): colorless liquid. H NMR (300
1
measurement of H and 13C NMR of complex A in the solid
MHz, CDCl3): δ 0.87 (t, J ) 7.5 Hz, 3 H), 0.94 (t, J ) 7.2 Hz, 3 H),
1.40-1.56 (m, 4 H), 2.09-2.20 (m, 4 H), 5.87 (t, J ) 7.5 Hz, 1 H),
7.17-7.33 (m, 5 H). 13C NMR (75 MHz, CDCl3): δ 13.8, 14.0, 21.8,
22.8, 31.3, 33.1, 126.0, 128.7, 129.7, 133.4, 135.9, 137.2. IR (NaCl):
3071, 2960, 2870, 1583, 1476, 1439, 1378, 1233, 1151, 1087, 1025,
898, 740, 691 cm-1. MS (EI): m/z 220 (M+, 100.0). Anal. Calcd for
C14H20S: C, 76.30; H, 9.15; S, 14.55. Found: C, 76.17; H, 9.07; S,
14.44.
state. Thanks are due to the Instrumental Analysis Center,
Faculty of Engineering, Osaka University, for assistance in
obtaining NMR spectra with the JEOL JNM-GSX-400 instru-
ment, mass spectra with the JEOL JMS-DX303 instrument, and
elemental analyses.
Supporting Information Available: 1H and 13C NMR
spectra of complex A in the solid state. This material is available
free of charge via the Internet at http://pubs.acs.org.
(E)-2-(Phenylthio)-2-methylstyrene (4o): colorless liquid. 1H NMR
(300 MHz, CDCl3): δ 2.14 (s, 3 H), 6.68 (s, 1 H), 7.22-7.47 (m, 10
H). 13C NMR (75 MHz, CDCl3): δ 19.7, 126.7, 127.3, 128.2, 128.6,
129.0, 130.6, 132.0, 133.7, 138.8, 137.0. IR (NaCl): 3058, 3022, 2932,
JA983949I