Calcium carbide as a convenient acetylene source in the synthesis of unsaturated sulfides, promising functionalized monomers

Article abstract of DOI:10.1016/j.mencom.2015.11.004

Calcium carbide was studied as a useful solid-state reagent to incorporate acetylene unit into synthetic procedures. Atom-economic thiol-yne click reaction was successfully performed with single and double additions. Heterocyclic thiols and aliphatic dithiols reacted with acetylene generated in situ from calcium carbide to afford corresponding vinyl sulfides and bis(thiovinyl)ethers in good to high yields.

Full text of DOI:10.1016/j.mencom.2015.11.004

Mendeleev
Communications
Mendeleev Commun., 2015, 25, 415–416
Calcium carbide as a convenient acetylene source in the synthesis
of unsaturated sulfides, promising functionalized monomers
Konstantin S. Rodygin,a Anton A. Kostina and Valentine P. Ananikov*a,b
a St. Petersburg State University, 119034 St. Petersburg, Russian Federation
b N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian
Federation. Fax: +7 499 135 5328; e-mail: val@ioc.ac.ru
DOI: 10.1016/j.mencom.2015.11.004
Calcium carbide was studied as a useful solid-state reagent to incorporate acetylene unit into synthetic procedures. Atom-economic
thiol-yne click reaction was successfully performed with single and double additions. Heterocyclic thiols and aliphatic dithiols reacted
with acetylene generated in situ from calcium carbide to afford corresponding vinyl sulfides and bis(thiovinyl)ethers in good to high
yields.
Acetylene is an outstanding building block in modern organic
chemistry with a variety of transformations already known,
including direct access to build molecular complexity with atomic
precision.1 Nevertheless, in spite of outstanding chemical poten-
tial, application of gaseous acetylene in everyday laboratory
practice is not an easy option since it requires a special dedicated
equipment and safety precautions.
Recently, we have shown that calcium carbide can be utilized
as a good acetylene source to access aliphatic and aromatic vinyl
sulfides2 (Scheme 1, A). These compounds are demanded in
organic synthesis as reagents in cycloaddition,3 Heck reaction,4
hydrosilylation,5 diimide reduction6 and asymmetric oxidation.7
For practical applications, vinyl thioethers are promising mono-
mers to produce functionalized polymers (Scheme 1, B). An
advantage of S-containing polymers concerns high refractive index
and applications in optoelectronics.8 Vinyl sulfides containing
a single sulfur atom allow one to obtain linear polymers and
copolymers (Scheme 1, B). The use of heterocyclic thiols (when
R is hetaryl) should provide a good option to construct highly
functionalized materials.
ethers is significantly less developed.9,10 Synthetic approaches to
heterocyclic containing thiovinyl ethers are also rather limited.9
In the present work, we demonstrate that vinyl monomers
containing heterocyclic moiety as well as bis(thiovinyl) deriva-
tives can be prepared by reaction of the corresponding thiols or
dithiols with calcium carbide. The reaction proceeds under mild
conditions and does not require a special laboratory set-up.
Usage of calcium carbide instead of gaseous acetylene simplifies
the procedure and avoids the need of dedicated high-pressure
equipment. Equally important, calcium carbide is an inexpensive
starting material convenient for storing, weighing and handling.
Optimization has shown that the reaction proceeded smoothly
in DMF or DMSO in the presence of a strong base and controlled
amount of water. Important solvent parameters include solvation
of calcium carbide, solubility of acetylene, optimal reaction tem-
perature and miscibility with water. In the case of heterocyclic
substrates DMSO is superior to DMF for the better solubility
of the reaction components. The amount of added water was an
important option for successful transformation. In the studied
reactions an optimal reagents ratios of CaC2 :H2O:thiol = 2:4:1
and CaC2 :H2O:dithiol = 4:8:1 were found.†
B
Thiol-yne click reaction proceeded sequentially in the case of
dithiols (Scheme 2, A). With stoichiometric amount of calcium
carbide a mixture of products was formed, including mono-
vinylated thiols, bisvinylated ethers and disulfides. Application of
an excess of calcium carbide increased the selectivity and provided
formation of only one product. Both thiol atoms were clicked to
acetylene unit via the atom-economic hydrothiolation reaction.
Products 1–3 with varying chain length (n = 4, 5 and 9) were
obtained in high isolated yields of 89–93% (Scheme 2, A).‡
+
x
y
R'
SR
R'
SR
RSH
A
linear
CaC2
This work HS(CH2)nCH2SH
x
y
S
R'
S
C
n
+
n
†
R'
Synthesis of vinyl sulfides. Potassium hydroxide (1.5 mmol), thiol
R'
S
S
(1 mmol)/dithiol (0.5 mmol), and water (4 mmol) were added to a reaction
tube (8 ml, Duran glass) with 1 ml of DMSO (DMF in the case of dithiols;
DMSO and DMF were stored under molecular sieves). Freshly powdered
calcium carbide (2 mmol) was added; the tube was sealed and placed in
100°C bath with vigorous stirring for 3 h. After heating the mixture was
diluted with 10% aqueous solution of KOH (10 ml), extracted with diethyl
ether (4×10 ml), organic layers were combined, washed with brine, dried over
Na2SO4, and concentrated in vacuo to yield a crude product.Thetemperature
during solvent evaporation should be controlled to avoid product loss due to
the volatility of some vinyl sulfides. The crude material was further purified
by column chromatography on silica gel (hexane and diethyl ether/hexane).
For further purification, if required, the products can be distilled in vacuo.
x
y
cross-linked
Scheme 1
Valuable opportunity may be opened by application of bis-
vinyl derivatives containing two sulfur atoms. Employment of these
monomers in the field of materials science facilitates formation
of cross-linked copolymers (Scheme 1, C).
On the moment a plethora of protocols for the synthesis of vinyl
sulfides were reported,9 whereas preparation of bis(thiovinyl)-
© 2015 Mendeleev Communications. Published by ELSEVIER B.V.
on behalf of the N. D. Zelinsky Institute of Organic Chemistry of the
Russian Academy of Sciences.
– 415 –

Mendeleev Commun., 2015, 25, 415–416
A
Mechanistic studies were supported by the Russian Science
H2O (4 equiv.),
KOH (1.5 equiv.)
DMF, 100 °C, 3 h
Foundation (grant no. 14-50-00126). Authors acknowledge Centre
for Magnetic Resonance, Centre for Chemical Analysis and Mate-
rials Research (St. Petersburg State University). This work was
partially supported by the Russian Foundation for Basic Research
(grant no. 15-33-20536). A.A.K. acknowledges St. Petersburg State
University for postdoctoral fellowship (no. 0.50.1186.2014).
S
n S
CaC2
+
n SH
HS
1 (n = 4), 89%
2 (n = 5), 91%
3 (n = 9), 93%
0.5 equiv.
2 equiv.
B
H2O (4 equiv.),
KOH (1.5 equiv.)
CaC2
+
HetSH
HetS
DMSO, 100 °C, 3 h
4–6
1 equiv.
2 equiv.
References
1 (a) V. P. Ananikov, L. L. Khemchyan, Yu. V. Ivanova, V. I. Bukhtiyarov,
A. M. Sorokin, I. P. Prosvirin, S. Z. Vatsadze, A. V. Medved’ko, V. N.
Nuriev, A. D. Dilman, V. V. Levin, I. V. Koptyug, K. V. Kovtunov,
V. V. Zhivonitko, V. A. Likholobov, A. V. Romanenko, P. A. Simonov,
V. G. Nenajdenko, O. I. Shmatova, V. M. Muzalevskiy, M. S. Nechaev,
A. F. Asachenko, O. S. Morozov, P. B. Dzhevakov, S. N. Osipov,
D. V. Vorobyeva, M. A. Topchiy, M. A. Zotova, S. A. Ponomarenko,
O. V. Borshchev,Yu. N. Luponosov, A. A. Rempel, A. A. Valeeva, A.Yu.
Stakheev, O.V. Turova, I. S. Mashkovsky, S.V. Sysolyatin,V.V. Malykhin,
G. A. Bukhtiyarova, A. O. Terent’ev and I. B. Krylov, Russ. Chem. Rev.,
2014, 83, 885; (b) V. P. Ananikov, ACS Catal., 2015, 5, 1964.
2 K. S. Rodygin and V. P. Ananikov, Green Chem., 2015, DOI: 10.1039/
C5GC01552A.
3 (a) W. H. Pearson, I. Y. Lee, Y. Mi and P. Stoy, J. Org. Chem., 2004, 69,
9109; (b) V. V. Kouznetsov, Tetrahedron, 2009, 65, 2721; (c) A. K. Shaikh,
A. J.A. Cobb and G.Varvounis, Org. Lett., 2012, 14, 584; (d) J. P. Dittami,
X. Y. Nie, H. Nie, H. Ramanathan, C. Buntel, S. Rigatti, J. Bordner, D. L.
Decosta and P. Williard, J. Org. Chem., 1992, 57, 1151; (e) J. H. Rigby,
J.-M. Sage and J. Raggon, J. Org. Chem., 1982, 47, 4815; (f) J. H.
Rigby and J.-M. Sage, J. Org. Chem., 1983, 48, 3591; (g) R. Brückner
and R. Huisgen, Tetrahedron Lett., 1990, 31, 2561.
N
N
N
4 Het =
5 Het =
6 Het =
N
N
N
H
H
Me
58%
91%
89%
Scheme 2
The presence of nitrogen atoms is required for several mate-
rials science applications. To explore the possibility of preparing
N-functionalized monomers we have subjected imidazole and
benzimidazole thiols to the S-vinylation (Scheme 2, B) and
obtained the target sulfides 4–6 in good (58%) to high (89–91%)
yields.‡
To summarize, we have developed an efficient procedure for
the preparation of bis(thiovinyl) derivatives and nitrogen func-
tionalized vinyl sulfides starting from inexpensive calcium carbide
and thiols under simple experimental conditions.
4 B. M. Trost and Y. Tanigawa, J. Am. Chem. Soc., 1979, 101, 4743.
5 B. Kopping, C. Chatgilialoglu, M. Zehnder and B. Giese, J. Org. Chem.,
1992, 57, 3994.
‡
Elemental analysis was carried out using a Euro EA3028-HT apparatus.
HRMS were recorded on a Bruker maXis Q-TOF instrument.
1
1,4-Bis(vinylthio)butane 1. H NMR (400 MHz, CDCl3) d: 1.78 (m,
6 R. M. Moriarty, R. K. Vaid and M. P. Duncan, Synth. Commun., 1987,
4H), 2.72 (m, 4H), 5.11 (d, 2H, J 16.7 Hz), 5.20 (d, 2H, J 10.3 Hz), 6.35
(dd, 1H, J 16.7 Hz, J 10.3 Hz). 13C NMR (100.6 MHz, CDCl3) d: 28.2,
31.0, 111.0, 132.3. MS, m/z (%): 115 (33), 86 (100), 85 (29), 73 (78),
55 (36), 45 (51). Found (%): C, 54.89; H, 8.06. Calc. for C8H14S2 (%):
C, 55.12; H, 8.09.
17, 703.
7 (a) F. A. Davis, R. T. Reddy, W. Han and P. J. Carroll, J. Am. Chem. Soc.,
1992, 114, 1428; (b) G. Glahsl and R. Herrmann, J. Chem. Soc., Perkin
Trans. 1, 1988, 1753; (c) G. E. O’Mahony, A. Ford and A. R. Maguire,
J. Sulfur Chem., 2013, 34, 301.
1
1,5-Bis(vinylthio)pentane 2. H NMR (400 MHz, CDCl3) d: 1.53 (m,
8 (a)J.-G. LiuandM. Ueda, J. Mater. Chem., 2009, 19, 8907;(b)K. Nakabayashi,
Yo. Abiko and H. Mori, Macromol., 2013, 46, 5998; (c) Yo. Abiko,
A. Matsumura, K. Nakabayashi and H. Mori, Polymer, 2014, 55, 6025;
(d) A. Kausar, S. Zulfiqar and M. I. Sarwar, Polym. Rev., 2014, 54, 185.
2H), 1.68 (q, 4H, J 7.4 Hz), 2.70 (t, 4H, J 7.3 Hz), 5.10 (d, 2H, J 16.7 Hz),
5.19 (d, 2H, J 10.2 Hz), 6.35 (dd, 2H, J 16.7 Hz, J 10.2 Hz). 13C NMR
(100.6 MHz, CDCl3) d: 28.1, 28.8, 31.3, 110.8, 132.5. MS, m/z (%): 87
(40), 86 (100), 73 (59), 69 (55), 67 (28), 45 (50), 41 (63). Found (%):
C, 57.27; H, 8.50. Calc. for C9H16S2 (%): C, 57.39; H, 8.56.
1,9-Bis(vinylthio)nonane 3. 1H NMR (400 MHz, CDCl3) d: 1.30 (br.m,
6H), 1.39 (br.m, 4H), 1.64 (q, 4H, J 7.4–7.6 Hz), 2.69 (t, 4H, J 7.3 Hz),
5.10 (d, 2H, J 16.7 Hz), 5.18 (d, 2H, J 10.2 Hz), 6.36 (dd, 2H, J 16.7 Hz,
J 10.2 Hz). 13C NMR (100.6 MHz, CDCl3) d: 29.0, 29.1, 29.3, 29.5,
31.5, 110.5, 132.7. MS, m/z (%): 101 (43), 87 (100), 81 (55), 85 (59), 73
(59), 69 (50), 55 (98). Found (%): C, 63.55; H, 9.84. Calc. for C13H24S2 (%):
C, 63.87; H, 9.90.
2-(Vinylthio)imidazole 4. 1H NMR (400 MHz, CDCl3) d: 5.31 (d, 1H,
J 16.7 Hz), 5.37 (d, 1H, J 9.6 Hz), 6.54 (dd, 1H, J 16.7 Hz, J 9.6 Hz), 7.16
(br.s, 2H). 13C NMR (100.6 MHz, CDCl3) d: 116.2, 124.7 (br.s), 129.7,
137.3. MS, m/z (%): 126 (42), 125 (100), 100 (37), 73 (24), 72 (65), 71
(25), 45 (39), 41 (39), 40 (21). Found (%): C, 47.45; H, 4.75; N, 22.15.
Calc. for C5H6N2S (%): C, 47.59; H, 4.79; N, 22.20.
9 (a) N. K. Gusarova, N. A. Chernysheva, S. V.Yas’ko and B. A. Trofimov,
Russ. Chem. Bull., Int. Ed., 2013, 62, 438 (Izv. Akad. Nauk, Ser. Khim.,
2013, 439); (b) B. A. Trofimov, N. K. Gusarova, A. S. Atavin, S. V.
Amosova, A. V. Gusarov, N. I. Kazantseva and G. A. Kalabin, Zh. Org.
Khim., 1973, 9, 8 (in Russian); (c) A. C. Fernandes and C. C. Romão,
Tetrahedron, 2006, 62, 9650; (d) B. W.Yoo, M. S. Song and M. C. Park,
Synth. Commun., 2007, 37, 3089; (e) E. Abele, O. Dzenitis, K. Rubina
and E. Lukevics, Chem. Heterocycl. Compd. (Engl. Transl.), 2002, 38,
682 (Khim. Geterotsikl. Soedin., 2002, 776); (f) M. L. Conte, S. Pacifico,
A. Chambery, A. Marra and A. Dondoni, J. Org. Chem., 2010, 75, 4644;
(g) A. Kondoh, K. Takami, H. Yorimitsu and K. Oshima, J. Org. Chem.,
2005, 70, 6468; (h) I. P. Beletskaya and V. P. Ananikov, Chem. Rev., 2011,
111, 1596; (i) V. P. Ananikov, N. V. Orlov and I. P. Beletskaya, Russ.
Chem. Bull., Int. Ed., 2005, 54, 576 (Izv. Akad. Nauk, Ser. Khim., 2005,
569); (j) Y. Okimoto, S. Sakaguchi and Ya. Ishii, J. Am. Chem. Soc.,
2002, 124, 1590.
2-Vinylthio-1-methylimidazole 5. 1H NMR (400 MHz, CDCl3) d: 3.66
(s, 3H), 5.14 (d, 1H, J 16.6 Hz), 5.34 (d, 1H, J 9.6 Hz), 6.47 (dd, 1H,
J 16.6 Hz, J 9.6 Hz), 7.02 (s, 1H), 7.12 (s, 1H). 13C NMR (100.6 MHz,
CDCl3) d: 34.6, 115.0, 123.4, 129.6, 130.2, 138.2. MS, m/z (%): 140 (42),
139 (100), 114 (19), 81 (25), 72 (39), 54 (15), 42 (40). MS [ESI-(+MS)],
m/z: 141.0483 [M+H]+ (calc. for C6H8N2S, m/z: 141.0481).
10 N. P. Petukhova, E. N. Prilezhaeva and V. N. Voropaev, Bull. Acad. Sci.
USSR, Div. Chem. Sci., 1972, 21, 911 (Izv. Akad. Nauk SSSR, Ser. Khim.,
1972, 954).
2-(Vinylthio)benzimidazole 6. 1H NMR (400 MHz, CDCl3) d: 5.38 (dd,
1H, J 9.2 Hz, J 1.2 Hz), 5.68 (dd, 1H, J 16.2 Hz, J 1.2 Hz), 7.22–7.29 (m,
3H), 7.46 (dd, 1H, J 16.2 Hz, J 9.2 Hz), 7.50–7.55 (m, 1H). 13C NMR
(100.6 MHz, CDCl3) d: 107.2, 110.4, 110.9, 123.4, 124.1, 129.8, 131.0,
168.3. MS, m/z (%): 176 (52), 175 (100), 150 (23), 122 (19), 118 (22),
91 (17), 90 (16), 63 (21). Found (%): C, 61.16; H, 4.54; N, 15.77. Calc.
for C9H8N2S (%): C, 61.34; H, 4.58; N, 15.90.
Received: 15th September 2015; Com. 15/4733
– 416 –