A concise synthesis of (alkynyl)(trifluoromethyl)sulfanes via a bismuth(iii)-promoted reaction of trimethyl(alkynyl)silane with trifluoromethanesulfanylamide

Article abstract of DOI:10.1039/c4ob01451k

A bismuth(iii)-promoted reaction of trimethyl(alkynyl)silanes with trifluoromethanesulfanylamide is developed, giving rise to (alkynyl)(trifluoromethyl)sulfanes in good yields.

Full text of DOI:10.1039/c4ob01451k

Organic &
Biomolecular Chemistry
View Article Online
View Journal
PAPER
A concise synthesis of (alkynyl)(trifluoromethyl)-
sulfanes via a bismuth(III)-promoted reaction of
trimethyl(alkynyl)silane with trifluoromethane-
sulfanylamide†
Cite this: DOI: 10.1039/c4ob01451k
Jie Shenga and Jie Wu*a,b
Received 10th July 2014,
Accepted 6th August 2014
DOI: 10.1039/c4ob01451k
A
bismuth(III)-promoted reaction of trimethyl(alkynyl)silanes with trifluoromethanesulfanylamide is
www.rsc.org/obc
developed, giving rise to (alkynyl)(trifluoromethyl)sulfanes in good yields.
1. Introduction
In the last decade, we have focused on the synthesis of natural
product-like compounds with privileged structures.1 The sub-
sequent construction and screening of related libraries result
in the discovery of some hits for several biological assays. With
an expectation to improve the corresponding biological activi-
ties and find more active compounds, we have been interested
in the introduction of the fluoro atom into small molecules.2
So far, some approaches have been appeared for the incorpor-
ation of fluoro-containing groups into organic compounds,3,4
such as the (trifluoromethyl)thio moiety (SCF3). Due to the
high hydrophobicity of the (trifluoromethyl)thio moiety,5
methods for nucleophilic trifluoromethylthiolation and elec-
trophilic trifluoromethylthiolation have been developed.6–8
Among the reagents reported for trifluoromethylthiolation,
much attention has been paid to trifluoromethanesulfanyl-
amide, which was recognized as an equivalent of the trifluoro-
methanesulfanyl cation (CF3S+). Its good reactivity for the
formation of the C–SCF3 bond has been demonstrated.7a
Recently, we reported the formation of (trifluoromethyl)thio-
substituted indoles, benzofurans, and benzothiophenes using
trifluoromethanesulfanylamide as the source of the trifluoro-
methanesulfanyl cation.2a–c During the reaction process, the
presence of bismuth(III) chloride was crucial for the successful
transformation.
Scheme 1 Proposed route for the synthesis of CF3S-containing
heterocycles.
the subsequent biological evaluation, we conceived that tri-
fluoromethylthiolation would be a good vehicle to generate the
(trifluoromethyl)thio-containing heterocycles. Prompted by
our interest in the [3 + 2] cycloaddition of isoquinoline-
N-oxide9 or isoquinolinium-2-ylamide,10 we envisioned that
(alkynyl)(trifluoromethyl)sulfanes would be a good choice as
the reaction partner (Scheme 1). However, examples for access
to (arylethynyl)(trifluoromethyl)sulfanes remain rare.6a,b,8a,b
Therefore, we initiated a program to consider to produce
(alkynyl)(trifluoromethyl)sulfanes.
2. Results and discussion
Initially, the reaction of ethynylbenzene with trifluoromethane-
sulfanylamide was investigated. Although bismuth(III) chloride
was demonstrated as the most efficient one in several transfor-
mations,2a–c different Lewis acids including bismuth(III) chlor-
ide were examined. However, all reactions failed to give rise to
the expected product (Scheme 2, eqn (1)). We reasoned that
the addition of a base would be beneficial for the generation
of the alkyne anion, which would facilitate the subsequent
nucleophilic attack of the trifluoromethanesulfanyl cation.
However, it would deactivate the role of the Lewis acid if a
base was added in the reaction system. Therefore, we shifted
our focus to trimethyl(alkynyl)silanes. We hypothesized that
As mentioned above, we have generated some libraries with
privileged scaffolds.1 In order to get more active molecules in
aDepartment of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433,
China. E-mail: jie_wu@fudan.edu.cn; Fax: +8621 6564 1740; Tel: +86 21 6510 2412
bState Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic
Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China
†Electronic supplementary information (ESI) available: Experimental procedure,
characterization data, and 1H and 13C NMR spectra of compounds 3. See DOI:
10.1039/c4ob01451k
This journal is © The Royal Society of Chemistry 2014
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
decreased to 1.0 equiv. (Table 1, entry 2). Interestingly, ((3-
methoxyphenyl)ethynyl)(trifluoromethyl)sulfane 3a was pro-
duced in 88% yield when 2.0 equiv. of bismuth(III) chloride
were added in the reaction (Table 1, entry 3). No reaction
occurred in a control experiment without the addition of
bismuth(III) chloride (Table 1, entry 4). The reaction was
further screened at different temperatures (Table 1, entries
5–8). A similar yield was observed when the reaction took place
at 100 °C, while inferior results were obtained when the reac-
tion temperature was lowered. We next examined the trans-
formation in various solvents (Table 1, entries 9–14). Only a
trace amount of the product was detected when toluene was
used as the solvent. Compound 3a could be afforded in 73%
yield when the reaction occurred in MeCN. The results were
poor when other solvents were utilized. The efficiency was
affected when the reaction was performed under an air atmos-
phere (Table 1, entry 15). Compared to the result obtained in
DCE, the yield from a mixed solvent (DCE–MeCN = 1 : 1) was
inferior, leading to compound 3a in 75% yield (Table 1, entry
16). Only a trace amount of the product was detected when
BiCl3 was changed to FeCl3, CuCl2, or TsOH (Table 1, entries
17, 18 and 20). No desired product was detected when ZnF2
was employed as the Lewis acid (Table 1, entry 19). A trace
amount of the product was observed when TMS in the
substrates was replaced by other leaving groups, such as TES,
TBS, and TIPS (data not shown in Table 1).
Scheme 2 Generation of (alkynyl)(trifluoromethyl)sulfanes.
the presence of bismuth(III) chloride would activate trifluoro-
methanesulfanylamide 2 to afford trifluoromethanesulfanyl
cations and chloride, which would react with trimethyl-
(alkynyl)silane 1 leading to the desired (alkynyl)(trifluoro-
methyl)sulfane 3 (Scheme 2, eqn (2)). With this consideration
in hand, we started to explore the possibility of this
transformation.
At the beginning, the reaction of ((3-methoxyphenyl)-
ethynyl)trimethylsilane 1a with trifluoromethanesulfanyl-
amide 2 promoted by bismuth(III) chloride was selected as the
model. The reaction was initially performed in dichloroethane
(DCE) at 80 °C in the presence of bismuth(III) chloride (1.5
equiv.). To our delight, the corresponding product 3a was
obtained and isolated in 36% yield (Table 1, entry 1). The yield
was lower when the amount of bismuth(III) chloride was
Table 2 Synthesis of (alkynyl)(trifluoromethyl)sulfanes via a bismuth(III)-
promoted reaction of trimethyl(alkynyl)silane with trifluoromethane-
sulfanylamidea
Table 1 Initial studies for the bismuth(III)-promoted reaction of ((3-
methoxyphenyl)ethynyl)trimethylsilane 1a with trifluoromethanesulfa-
nylamide 2
Entry [Bi]
Solvent
T (°C) Yielda (%)
1
2
3
4
5
6
7
8
BiCl3 (1.5 equiv.)
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
80
80
80
80
36
29
88
NR
Trace
62
66
87
ND
ND
Trace
73
ND
ND
62
BiCl3 (1.0 equiv.)
BiCl3 (2.0 equiv.)
—
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
BiCl3 (2.0 equiv.)
FeCl3 (2.0 equiv.)
rt
40
60
100
80
80
80
80
80
80
80
80
80
80
80
80
9
DMA
10
11
12
13
14
15b
16
17
18
19
20
DMSO
Toluene
CH3CN
THF
DMF
DCE
DCE–CH3CN (1 : 1)
DCE
75
Trace
Trace
ND
Trace
CuCl2 (2.0 equiv.) DCE
ZnF2 (2.0 equiv.)
TsOH (2.0 equiv.)
DCE
DCE
a Isolated yield based on ((3-methoxyphenyl)ethynyl)trimethylsilane 1a.
b Under an air atmosphere.
a Isolated yield based on trimethyl(arylethynyl)silane 1.
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2014

View Article Online
Organic & Biomolecular Chemistry
Paper
and bismuth(III) chloride (0.4 mmol, 126.2 mg) in DCE
(2.0 mL). The mixture was stirred at 80 °C for 8–12 hours. After
completion of the reaction as indicated by TLC, the reaction
mixture was filtered with silica gel and washed with CH2Cl2
(3 × 5.0 mL). The mixture was concentrated in vacuo and the
residue was purified by column chromatography on silica gel
to provide the product 3.
Scheme 3 Reaction of 1,4-bis((trimethylsilyl)ethynyl)benzene 1m with
trifluoromethanesulfanylamide 2.
(2-(3-Methoxyphenyl)ethynyl)(trifluoromethyl)sulfane (3a).
1
Yellow oil; H NMR (400 MHz, CDCl3) δ 3.87 (s, 3H), 6.93–7.00
(m, 2H), 7.09 (d, J = 7.6 Hz, 1H), 7.25 (t, J = 8.0 Hz, 1H);
13C NMR (100 MHz, CDCl3) δ 55.3, 66.5, 101.2, 116.4, 116.8,
122.4, 124.7, 128.1 (q, J = 310.3 Hz), 129.6, 159.3; 19F NMR
After establishing the optimized conditions (2.0 equiv. of
bismuth(III) chloride, DCE, 80 °C), we next explored the scope
generality of this bismuth(III)-promoted reaction of trimethyl-
(alkynyl)silanes with trifluoromethanesulfanylamide. The
results are presented in Table 2. It was found that all reactions
worked well to furnish the desired products in good yields. Tri-
methyl(alkynyl)silanes with different substitutions on the aro-
matic ring were all good partners. Different functional groups
including halo, methoxy, methyl, methylthio, carbonyl (ester or
ketone), and nitro were compatible under the standard con-
ditions. For instance, 1-(4-(((trifluoromethyl)thio)ethynyl)phenyl)-
ethanone 3j was formed in 90% yield. Additionally, trimethyl-
(thiophen-2-ylethynyl)silane reacted with trifluoromethanesul-
fanylamide well, providing the desired product 3k in 72% yield.
The reaction of 1,4-bis((trimethylsilyl)ethynyl)benzene 1m
with trifluoromethanesulfanylamide 2 was examined as well
(Scheme 3). As expected, the corresponding 1,4-bis(((trifluoro-
methyl)thio)ethynyl)benzene 3m was formed in 65% yield.
Reactions of alkyl-substituted silanes were explored under
the standard conditions subsequently. However, no desired
product was formed.
(378 MHz, CDCl3)
δ −44.00 (s); HRMS (ESI) calcd for
C10H8F3OS: 233.0242 (M + H+), found: 233.0248.
(2-(4-Chlorophenyl)ethynyl)(trifluoromethyl)sulfane (3b).
1
Yellow oil; H NMR (400 MHz, CDCl3) δ 7.33 (dd, J1 = 6.8 Hz,
J2 = 1.8 Hz, 2H), 7.43 (dd, J1 = 6.8 Hz, J2 = 1.8 Hz, 2H);
13C NMR (100 MHz, CDCl3) δ 67.9, 100.1, 120.0, 128.0 (q, J =
311.0 Hz), 128.9, 133.4, 136.0; 19F NMR (378 MHz, CDCl3)
δ −43.86 (s); HRMS (ESI) calcd for C9H5ClF3S: 236.9747
(M + H+), found: 236.9758.
(2-(4-Bromophenyl)ethynyl)(trifluoromethyl)sulfane (3c).
1
Yellow oil; H NMR (400 MHz, CDCl3) δ 7.35 (dt, J1 = 8.8 Hz,
J2 = 2.0 Hz, 2H), 7.49 (dt, J1 = 8.8 Hz, J2 = 2.0 Hz, 2H); 13C NMR
(100 MHz, CDCl3) δ 68.1, 100.2, 120.4, 124.3, 127.9 (q, J = 311.0
Hz), 131.8, 133.5; 19F NMR (378 MHz, CDCl3) δ −43.83 (s);
HRMS (ESI) calcd for C9H5BrF3S: 280.9242 (M + H+), found:
280.9240.
(2-(4-Fluorophenyl)ethynyl)(trifluoromethyl)sulfane (3d).
Brown oil; 1H NMR (400 MHz, CDCl3) δ 7.03–7.07 (m, 2H),
7.48–7.51 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 66.7, 100.2,
2
111.8, 115.9 (d, JCF = 22.6 Hz), 128.1 (q, J = 310.8 Hz), 134.52
3
1
(d, JCF = 8.6 Hz), 163.4 (d, JCF = 251.6 Hz); 19F NMR
(378 MHz, CDCl3) δ −44.03 (s), −108.37 (s); HRMS (ESI) calcd
for C9H5F4S: 221.0043 (M + H+), found: 221.0057.
3. Conclusion
(2-p-Tolylethynyl)(trifluoromethyl)sulfane (3e). Yellow oil;
1H NMR (400 MHz, CDCl3) δ 2.37 (s, 3H), 7.16 (d, J = 8.0 Hz,
2H), 7.40 (d, J = 8.0 Hz, 2H); 13C NMR (100 MHz, CDCl3)
δ 21.6, 65.8, 101.6, 118.5, 128.2 (q, J = 310.8 Hz), 129.3, 132.3,
140.3; 19F NMR (378 MHz, CDCl3) δ −44.26 (s); HRMS (ESI)
calcd for C10H8F3S: 217.0293 (M + H+), found: 217.0281.
(2-o-Tolylethynyl)(trifluoromethyl)sulfane (3f). Brown oil;
1H NMR (400 MHz, CDCl3) δ 2.45 (s, 3H), 7.17 (t, J = 7.5 Hz,
1H), 7.23 (d, J = 7.6 Hz, 1H), 7.29 (td, J = 7.6, 1.2 Hz, 1H), 7.45
(d, J = 7.6 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 20.5, 70.1,
100.4, 121.4, 125.7, 128.2 (q, J = 303.9 Hz), 129.7, 132.3, 141.3;
19F NMR (378 MHz, CDCl3) δ −44.32 (s); HRMS (ESI) calcd for
C10H8F3S: 217.0293, found: 217.0295.
In conclusion, we have described
a concise synthesis
of (alkynyl)(trifluoromethyl)sulfanes through a bismuth(III)-
promoted reaction of trimethyl(alkynyl)silanes with tri-
fluoromethanesulfanylamide. The transformation proceeds
smoothly under mild conditions affording the corresponding
products in good yields. The presence of bismuth(III) chloride
shows its efficiency once again for the introduction of the (tri-
fluoromethyl)thio moiety into small molecules. Currently,
synthesis of CF3S-containing heterocycles using (alkynyl)-
(trifluoromethyl)sulfanes as the starting materials is ongoing
in our laboratory.
(2-Phenylethynyl)(trifluoromethyl)sulfane (3g). Brown oil;
1H NMR (400 MHz, CDCl3) δ 7.36–7.39 (m, 2H), 7.42–7.43
(m, 1H), 7.50–7.52 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 66.7,
101.3, 121.5, 128.0 (q, J = 294.8 Hz), 128.5, 129.7, 132.2;
19F NMR (378 MHz, CDCl3) δ −44.08 (s); HRMS (ESI) calcd for
C9H6F3S: 203.0137 (M + H+), found: 203.0131.
4. Experimental section
General procedure for the synthesis of (alkynyl)-
(trifluoromethyl)sulfanes via a bismuth(III)-promoted
reaction of trimethyl(alkynyl)silane with
trifluoromethanesulfanylamide
Trifluoromethanesulfanylamide 2 (0.3 mmol, 58.0 mg) was
1-(Methylthio)-2-(2-(trifluoromethylthio)ethynyl)benzene
added to a solution of trimethyl(alkynyl)silane 1 (0.2 mmol) (3h). Brown oil; 1H NMR (400 MHz, CDCl3) δ 2.49 (s, 3H), 7.11
This journal is © The Royal Society of Chemistry 2014
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
(td, J1 = 7.6 Hz, J2 = 0.7 Hz, 1H), 7.18 (d, J = 8.0 Hz, 1H),
7.33–7.37 (m, 1H), 7.45 (dd, J1 = 7.6 Hz, J2 = 1.0 Hz, 1H);
13C NMR (100 MHz, CDCl3) δ 15.1, 73.0, 98.7, 119.7, 124.3,
124.4, 128.0 (q, J = 311.0 Hz), 130.1, 133.1, 143.1; 19F NMR
Chem. Commun., 2014, 50, 5494; (d) Q. Xiao, J. Sheng,
Q. Ding and J. Wu, Eur. J. Org. Chem., 2014, 217;
(e) X. Wang, G. Qiu, L. Zhang and J. Wu, Tetrahedron Lett.,
2014, 55, 962.
(378 MHz, CDCl3)
δ
−43.86 (s); HRMS (ESI) calcd for
3 (a) R. Filler and Y. Kobayashi, in Biomedicinal Aspects of Flu-
orine Chemistry, Elsevier, Amsterdam, 1982; (b) Fluorine in
Bioorganic Chemistry, ed. J. T. Welch and S. Eswarakrish-
man, Wiley, New York, 1991.
C10H8F3S2: 249.0014 (M + H+), found: 249.0028.
Ethyl 4-(2-(trifluoromethylthio)ethynyl)benzoate (3i). Yellow
1
oil; H NMR (400 MHz, CDCl3) δ 1.40 (t, J = 7.1 Hz, 3H), 4.39
(q, J = 7.1 Hz, 2H), 7.54 (d, J = 8.4 Hz, 2H), 8.02 (d, J = 8.4 Hz,
2H); 13C NMR (100 MHz, CDCl3) δ 14.3, 61.3, 69.9, 100.5,
125.9, 127.9 (q, J = 293.9 Hz), 129.5, 131.1, 131.6, 165.7;
19F NMR (378 MHz, CDCl3) δ −43.62 (s); HRMS (ESI) calcd for
C12H10F3O2S: 275.0348 (M + H+), found: 275.0342.
4 For some reviews, see: (a) V. A. Petrov, in Fluorinated Hetero-
cyclic Compounds: Synthesis, Chemistry, and Applications,
John Wiley & Sons, Inc., Hoboken, NJ, 2009; (b) E. V. Nosova,
G. N. Lipunova, V. N. Charushin and O. N. Chupakhin,
J. Fluorine Chem., 2010, 131, 1267; (c) S. Zhu, Y. Wang,
W. Peng, L. Song and G. Jin, Curr. Org. Chem., 2002, 6,
1057; (d) M. J. Silvester, Aldrichimica Acta, 1991, 24, 31.
For some selective examples, see: (e) P. Kwiatkowski,
T. D. Beeson, J. C. Conrad and D. W. C. MacMillan, J. Am.
Chem. Soc., 2011, 133, 1738; (f) Y. Kishi, H. Nagura, S. Inagi
and T. Fuchigami, Chem. Commun., 2008, 3876;
(g) S. Fustero, S. Catalan, M. Sanchez-Rosello, A. Simon-
Fuentes and C. del Pozo, Org. Lett., 2010, 12, 3484; (h) T. Xu
and G. Liu, Org. Lett., 2012, 14, 5416; (i) X.-F. Wu,
H. Neumann and M. Beller, Chem. – Asian J., 2012, 7, 1744.
5 Bioorganic and Medicinal Chemistry of Fluorine, ed.
J.-P. Begue and D. Bonnet-Delpon, Wiley, Hoboken, 2008.
6 For selected examples, see: (a) C. Chen, L. Chu and
F.-L. Qing, J. Am. Chem. Soc., 2012, 134, 12454; (b) X. Shao,
X. Wang, T. Yang, L. Lu and Q. Shen, Angew. Chem., Int.
Ed., 2013, 52, 3457; (c) F. Baert, J. Colomb and T. Billard,
Angew. Chem., Int. Ed., 2012, 51, 10382; (d) G. Teverovskiy,
D. S. Surry and S. L. Buchwald, Angew. Chem., Int. Ed.,
2011, 50, 7312; (e) C.-P. Zhang and D. A. Vicic, J. Am. Chem.
Soc., 2012, 134, 183; (f) Z. Weng, W. He, C. Chen, R. Lee,
D. Tan, Z. Lai, D. Kong, Y. Yuan and K.-W. Huang, Angew.
Chem., Int. Ed., 2013, 52, 1548; (g) C. Chen, Y. Xie, L. Chu,
R.-W. Wang, X. Zhang and F.-L. Qing, Angew. Chem., Int.
Ed., 2012, 51, 2492; (h) C.-P. Zhang and D. A. Vicic, Chem. –
Asian J., 2012, 7, 1756; (i) L. D. Tran, I. Popov and
O. Daugulis, J. Am. Chem. Soc., 2012, 134, 18240;
(j) D. C. Remy, K. E. Rittle, C. A. Hunt and M. B. Freedman,
J. Org. Chem., 1976, 41, 1644; (k) D. J. Adams, A. Goddard,
J. H. Clark and D. J. Macquarrie, Chem. Commun., 2000, 987;
(l) O. A. Tomashenko and V. V. Grushin, Chem. Rev., 2011,
111, 4475; (m) K. P. Wang, S. Y. Yun, P. Mamidipalli and
D. Lee, Chem. Sci., 2013, 4, 3205; (n) M. Rueping,
N. Tolstoluzhsky and P. Nikolaienko, Chem. – Eur. J.,
2013, 19, 14043; (o) Y. D. Yang, A. Azuma, E. Tokunaga,
M. Yamasaki, M. Shiro and N. Shibata, J. Am. Chem. Soc.,
2013, 135, 8782.
1-(4-(2-(Trifluoromethylthio)ethynyl)phenyl)ethanone (3j).
1
Brown oil; H NMR (400 MHz, CDCl3) δ 2.60 (s, 3H), 7.55 (d,
J = 8.0 Hz, 2H), 7.92 (d, J = 8.2 Hz, 2H); 13C NMR (100 MHz,
CDCl3) δ 26.6, 70.4, 100.4, 127.9 (q, J = 311.2 Hz), 128.2, 128.3,
131.8, 137.2, 197.1; 19F NMR (378 MHz, CDCl3) δ −43.59 (s);
HRMS (ESI) calcd for C11H8F3OS: 245.0242 (M + H+), found:
245.0236.
2-(2-(Trifluoromethylthio)ethynyl)thiophene (3k). Yellow oil;
1H NMR (400 MHz, CDCl3) δ 7.00–7.04 (m, 1H), 7.27–7.30
(m, 1H), 7.38–7.42 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 71.4,
99.5, 123.4, 126.7, 127.9 (q, J = 314.9 Hz), 127.7, 130.3;
19F NMR (378 MHz, CDCl3) δ −44.18 (s); HRMS (ESI) calcd for
C7H4F3S2: 208.9701 (M + H+), found: 208.9707.
(2-(4-Methoxy-3-nitrophenyl)ethynyl)(trifluoromethyl)sulfane
1
(3l). Yellow oil; H NMR (400 MHz, CDCl3) δ 3.98 (s, 3H), 7.04
(d, J = 8.7 Hz, 1H), 7.64 (dd, J1 = 8.7 Hz, J2 = 2.1 Hz, 1H), 7.97
(d, J = 2.1 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 55.7, 78.0,
81.0, 113.5, 114.6, 128.8 (q, J = 313.3 Hz), 129.3, 131.7, 137.6,
153.0; 19F NMR (378 MHz, CDCl3) δ −43.69 (s); HRMS (ESI)
calcd for C10H7F3NO3S: 278.0093 (M + H+), found: 278.0085.
1,4-Bis(2-(trifluoromethylthio)ethynyl)benzene (3m). White
solid; 1H NMR (400 MHz, CDCl3) δ 7.46 (s, 4H); 13C NMR
(100 MHz, CDCl3) δ 69.6, 100.4, 122.6, 127.9 (q, J = 312.5 Hz),
131.9; 19F NMR (378 MHz, CDCl3) δ −43.71 (s); HRMS (ESI)
calcd for C12H5F6S2: 326.9731 (M + H+), found: 326.9745.
Acknowledgements
Financial support from the National Natural Science
Foundation of China (no. 21032007, 21172038) is gratefully
acknowledged.
Notes and references
1 For reviews, see: (a) Y. Luo, X. Pan, X. Yu and J. Wu, Chem.
Soc. Rev., 2014, 43, 834; (b) G. Qiu, Q. Ding and J. Wu,
Chem. Soc. Rev., 2013, 42, 5257; (c) H. Wang, Y. Kuang and
J. Wu, Asian J. Org. Chem., 2012, 1, 302.
2 (a) J. Sheng, S. Li and J. Wu, Chem. Commun., 2014, 50,
578; (b) Q. Xiao, J. Sheng, Z. Chen and J. Wu, Chem.
Commun., 2013, 49, 8647; (c) J. Sheng, C. Fan and J. Wu,
7 (a) A. Tlili and T. Billard, Angew. Chem., Int. Ed., 2013, 52,
6818; (b) Y. Yang, X. Jiang and F.-L. Qing, J. Org. Chem.,
2012, 77, 7538; (c) A. Ferry, T. Billard, E. Bacqué and
B. R. Langlois, J. Fluorine Chem., 2012, 134, 160;
(d) A. Ferry, T. Billard, B. R. Langlois and E. Bacqué, J. Org.
Chem., 2008, 73, 9362; (e) A. Ferry, T. Billard, B. R. Langlois
and E. Bacqué, Angew. Chem., Int. Ed., 2009, 48, 8551;
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2014

View Article Online
Organic & Biomolecular Chemistry
Paper
(f) T. Bootwicha, X. Liu, R. Pluta, I. Atodiresei and
M. Rueping, Angew. Chem., Int. Ed., 2013, 52, 12856;
(g) J. Liu, L. Chu and F.-L. Qing, Org. Lett., 2013, 15, 894;
(h) W. A. Sheppard, J. Org. Chem., 1964, 29, 895;
(b) G. Liu, H. Liu, S. Pu and J. Wu, RSC Adv., 2013, 3,
10666; (c) Q. Xiao, J. Sheng, Q. Ding and J. Wu, Eur. J. Org.
Chem., 2014, 217; (d) Q. Xiao, S. Ye and J. Wu, Org. Lett.,
2012, 14, 3430.
(i) S. Alazet, L. Zimmer and T. Billard, Angew. Chem., Int. 10 For selected examples, see: (a) Z. Chen, X. Yang and J. Wu,
Ed., 2013, 52, 10814; ( j) D. Enders, C. Grondal and
M. R. M. Hüttl, Angew. Chem., Int. Ed., 2007, 46, 1570;
(k) X. Wang, T. Yang, X. Cheng and Q. Shen, Angew. Chem.,
Int. Ed., 2013, 52, 12860; (l) Q. H. Deng, C. Rettenmeier,
H. Wadepohl and L. H. Gade, Chem. – Eur. J., 2014, 20, 93;
(m) S. Munavalli, D. K. Rohrbaugh, D. I. Rossman, F. J. Berg,
G. W. Wagner and H. D. Durst, Synth. Commun., 2000, 30, 2847.
8 (a) R. Pluta, P. Nikolaienko and M. Rueping, Angew. Chem.,
Int. Ed., 2014, 53, 1650; (b) C. Xu, B. Ma and Q. Shen,
Angew. Chem., Int. Ed., 2014, 53, DOI: 10.1002/
anie.201403983; (c) M. Rueping, X. Liu, T. Bootwicha,
R. Pluta and C. Merkens, Chem. Commun., 2014, 50, 2508.
9 For selected examples, see: (a) J. Sheng, C. Fan, Y. Ding,
X. Fan and J. Wu, Chem. Commun., 2014, 50, 4188;
Chem. Commun., 2009, 3469; (b) S. Li, Y. Luo and J. Wu,
Org. Lett., 2011, 13, 4312; (c) S. Ye, X. Yang and J. Wu,
Chem. Commun., 2010, 46, 5238; (d) Z. Chen and J. Wu,
Org. Lett., 2010, 12, 4856; (e) Z. Chen, X. Yu and J. Wu,
Chem. Commun., 2010, 46, 6356; (f) Z. Chen, L. Gao, S. Ye,
Q. Ding and J. Wu, Chem. Commun., 2012, 48, 3975;
(g) X. Yu, S. Ye and J. Wu, Adv. Synth. Catal., 2010, 352,
2050; (h) X. Yu, Z. Chen, X. Yang and J. Wu, J. Comb.
Chem., 2010, 12, 374; (i) S. Li and J. Wu, Org. Lett., 2011,
13, 712; ( j) Q. Xiao, J. Sheng, Q. Ding and J. Wu, Adv.
Synth. Catal., 2013, 355, 2321; (k) Z. Chen, Q. Ding, X. Yu
and J. Wu, Adv. Synth. Catal., 2009, 351, 1692; (l) G. Liu,
H. Liu, G. Qiu, S. Pu and J. Wu, Chem. Commun., 2012, 48,
7049.
This journal is © The Royal Society of Chemistry 2014
Org. Biomol. Chem.