E.S. Degtyareva et al.
AppliedCatalysisA,General571(2019)170–179
phosphine ligand, they selectively promote formation of either 1,2-bis
(alkylthio)alkenes or 1,4-bis(arylthio)-1,3-dienes. However, the unique
physical and chemical properties of C2H2 strongly distinguish it from
other alkynes, thereby specific optimization of the catalytic system and
reaction conditions is required for C2H2 involvement in the reaction.
In this study, we report an efficient catalytic system to obtain 1,2-bis
(arylthio)ethenes or 1,4-bis(arylthio)-1,3-butadienes from acetylene in
a highly selective manner. Controlled switching of the reaction toward
one particular product is accomplished by specific choice of the ligand.
As a result, two products can be obtained on demand in good to high
yields and with high selectivity. Derivatives from acetylene are valuable
for obtaining new materials and there is a particular practical demand
for selective catalysts efficient in for synthesis of complex structures
from small available molecules (acetylene).
0.18 ml) was added to the second one. Both vessels were closed im-
mediately. The vessel with reagents was placed into a heating block
(t = 60 °C). The reaction was carried out under stirring for 1 h.
2.2. Characterization data
The 1a [41] product was identified according to the published data.
2.2.1. (Z)-1,2-bis(4-tolylthio)ethene (1b)
White solid. 1H NMR (300 MHz, Acetone-d6) δ, ppm: 7.32 (d,
J = 8.2 Hz, 4 H), 7.21 (d, J = 8.1 Hz, 4 H), 6.58 (s, 2 H), 2.32 (s, 6 H).
13C NMR (75 MHz, Acetone-d6) δ, ppm: 137.84, 132.48, 130.86,
130.26, 125.41, 20.97. HRMS (ESI-TOF): m/z calcd for [M + Ag]+
378.9739, found 378.9758 (Δ = 5 ppm).
:
2. Experimental
2.2.2. (Z)-1,2-bis(3-tolylthio)ethene (1c)
Yellow oil. 1H NMR (300 MHz, Acetone-d6) δ, ppm: 7.30 – 7.20 (m,
6 H), 7.15 – 7.07 (m, 2 H), 6.67 (s, 2 H), 2.34 (s, 6 H). 13C NMR
(75 MHz, Acetone-d6) δ, ppm: 140.06, 135.79, 130.32, 130.04, 128.57,
2.1. General procedures
126.88, 125.32, 21.26. HRMS (ESI-TOF): m/z calcd for [M]+
273.0766, found 273.0746 (Δ = 7.3 ppm).
:
Unless noted otherwise, the synthetic work was carried out under
argon atmosphere. All synthetic procedures were designed for solvents
presaturated with acetylene at 0 °C, which is mandatory to reach the
best yields. The disulfides were prepared according to the previously
published procedure [40]. The other reagents were obtained from
Sigma Aldrich and used as supplied (checked by NMR before use). The
solvents were purified according to the published methods. 1H and 13C
chemical shifts are reported relative to the corresponding solvent sig-
nals used as an internal reference.
2.2.3. (Z)-1,2-bis((4-bromophenyl)thio)ethene (1d)
White solid. 1H NMR (300 MHz, CDCl3) δ, ppm: 7.45 (d, J = 8.6 Hz,
4 H), 7.26 (d, J = 8.5 Hz, 4 H), 6.49 (s, 2 H). 13C NMR (75 MHz, CDCl3)
δ, ppm: 134.31, 132.39, 131.12, 125.35, 121.21. HRMS (ESI-TOF): m/z
calcd for [M + Ag]+: 506.7636, found 506.7637 (Δ = 0.2 ppm).
2.2.4. (Z)-1,2-bis((3-bromophenyl)thio)ethene (1e)
2.1.1. General Synthetic Procedure for synthesis of (Z)-1,2-bis(arylthio)
ethene (1)
White solid. 1H NMR (300 MHz, Acetone-d6) δ, ppm: 7.60 (s, 2 H),
7.51 – 7.41 (m, 4 H), 7.35 (t, J = 7.9 Hz, 2 H), 6.84 (s, 2 H). 13C NMR
(75 MHz, Acetone-d6) δ, ppm: 138.37, 131.93, 131.74, 130.75, 128.42,
125.89, 123.53. HRMS (ESI-TOF): m/z calcd for [M + Ag]+: 506.7636,
found 506.7629 (Δ = 1.4 ppm).
Acetylene was bubbled through acetonitrile in a water-ice bath for
30 min. The solid reagents including disulfide (0.2 mmol), Ni(acac)2
(6 × 10−3 mmol, 0.0015 g), and PPh3 (6 × 10-2 mmol, 0.0157 g) were
added into a screw-capped test tube. The test tube with the solid re-
agents was flushed with argon, and the presaturated MeCN (1 ml) was
added. The tube was immediately closed with a screw cap. The reaction
was carried out at 60 °C under stirring for 2 days. After completing the
reaction, the solvent was evaporated on a rotary evaporator and the
product was purified by flash chromatography on silica gel 60 (0.015-
0.040 mm) with hexane/CH2Cl2 gradient elution. After drying under
vacuum, the pure products were obtained.
2.2.5. (Z)-1,2-bis((2-bromophenyl)thio)ethene (1f)
Light oil. 1H NMR (300 MHz, CDCl3) δ, ppm: 7.60 (dd, J = 8.0,
1.4 Hz, 2 H), 7.40 (dd, J = 7.9, 1.7 Hz, 2 H), 7.31 (td, J = 7.6, 1.4 Hz,
2 H), 7.15 – 7.05 (m, 2 H), 6.64 (s, 2 H). 13C NMR (75 MHz, CDCl3) δ,
ppm: 136.53, 133.37, 130.03, 128.12, 126.23, 124.03. HRMS (ESI-
TOF): m/z calcd for [M + Ag]+
(Δ = 0.8 ppm).
:
506.7636, found 506.7640
2.1.2. General synthetic procedure for (Z,Z)-1,4-bis(arylthio)buta-1,3-
diene (2)
2.2.6. (Z)-1,2-bis((4-methoxyphenyl)thio)ethene (1g)
Yellow oil. 1H NMR (300 MHz, Acetone-d6) δ, ppm: 7.38 (d,
J = 8.9 Hz, 4 H), 6.96 (d, J = 8.9 Hz, 4 H), 6.43 (s, 2 H), 3.81 (s, 6 H).
13C NMR (75 MHz, Acetone-d6) δ, ppm: 160.42, 132.81, 126.33,
Acetylene was bubbled through DMF in a water-ice bath for 30 min.
The disulfide (0.2 mmol), Ni(acac)2 (6 × 10−3 mmol, 0.0015 g), and
PPhCy2 (6 × 10-2 mmol, 0.0165 g) were added into a screw-capped
test-tube. The test tube with the solid reagents was flushed with argon,
and the presaturated DMF (3 ml) was added. The test tube was im-
mediately closed with a screw cap connected to an acetylene balloon
via an adapter. The reaction was carried out at 60 °C under stirring for
1 h. After completing the reaction, the solvent was evaporated on a
rotary evaporator and the product was purified by flash chromato-
graphy on silica 60 (0.015-0.040 mm) with hexane/CH2Cl2 gradient
elution. After drying under vacuum, the pure products were obtained as
light yellow solids.
125.63, 115.81, 55.74. HRMS (ESI-TOF): m/z calcd for [M + Ag]+
:
410.9637, found 410.9648 (Δ = 2.7 ppm). CCDC-1864715 contains the
supplementary crystallographic data for this substance. These data can
be obtained free of charge from The Cambridge Crystallographic Data
2.2.7. (Z)-1,2-bis((4-chlorophenyl)thio)ethene (1h)
White solid. 1H NMR (300 MHz, CDCl3) δ, ppm: 7.38 – 7.28 (m,
8 H), 6.50 (s, 2 H). 13C NMR (75 MHz, CDCl3) δ, ppm: 133.64, 133.32,
130.94, 129.47, 125.38. HRMS (ESI-TOF): m/z calcd for [M + Ag]+
418.8646, found 418.8648 (Δ = 0.5 ppm).
:
2.1.3. Synthesis of (Z,Z)-1,4-bis(phenylthio)-1,3-butadiene (2a) using
CaC2
The reaction was carried out in a screw-capped H-type test-tube.
One vessel was charged with Ph2S2 (0.2 mmol, 43.6 mg), Ni(acac)2
(6 × 10−3 mmol, 1.5 mg), and PPhCy2 (6 × 10-2 mmol, 16.4 mg).
Calcium carbide (2.5 mmol, 160.2 mg) and DMF (1 ml) were loaded
into another vessel. Afterwards, DMF presaturated with C2H2 (3 ml)
was quickly added to the first vessel, and distilled water (10 mmol,
2.2.8. (1Z,3Z)-1,4-bis(phenylthio)buta-1,3-diene (2a)
White solid. 1H NMR (300 MHz, CDCl3) δ, ppm: 7.43 – 7.37 (m,
4 H), 7.37 – 7.29 (m, 4 H), 7.30-7.19 (m, 2 H), 6.76 – 6.64 (m, 2 H),
6.45 – 6.33 (m, 2 H). 13C NMR (75 MHz, CDCl3) δ, ppm: 135.69,
129.57, 129.27, 127.13, 126.97, 125.03. HRMS (ESI-TOF) m/z calcd for
[M + Ag]+: 376.9582, found 376.9579 (Δ = 0.8 ppm).
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