Atom-Economical Thiocyanation-Amination of Alkynes with N-Thiocyanato-Dibenzenesulfonimide

Article abstract of DOI:10.1021/acs.joc.0c02780

A highly regioselective protocol for intermolecular thiocyanation-amination of alkynes by N-thiocyano-dibenzenesulfonimide (NTSI) as the SCN and nitrogen sources has been developed. A C-S bond and C-N bond are simultaneously constructed in only one step. The reaction under simple mild conditions features a broad substrate scope, atom economy, high yields (up to 94%), and excellent functional group tolerance.

Full text of DOI:10.1021/acs.joc.0c02780

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Note
Atom-Economical Thiocyanation-Amination of Alkynes with
N‑Thiocyanato-Dibenzenesulfonimide
Haopeng Wu, Chukai Shao, Di Wu, Liang Jiang, Hongquan Yin,* and Fu-Xue Chen*
Cite This: J. Org. Chem. 2021, 86, 5327−5335
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ABSTRACT: A highly regioselective protocol for intermolecular thiocyanation-amination of alkynes by N-thiocyano-
dibenzenesulfonimide (NTSI) as the SCN and nitrogen sources has been developed. A C−S bond and C−N bond are
simultaneously constructed in only one step. The reaction under simple mild conditions features a broad substrate scope, atom
economy, high yields (up to 94%), and excellent functional group tolerance.
constructing a C(sp2)−SCN bond is still limited comparing
n recent decades, the method of synthesizing organic
Ithiocyanates has attracted a lot of attention owing to their with a C(sp3)−SCN bond. As far as we know, there is only one
case of thiocyanation of alkynes,5 in which the C(sp)−SCN
bond is constructed. But the construction of the C(sp2)−SCN
bond has not been achieved by the electrophilic thiocyanation
of alkynes. Thus, the electrophilic thiocyanation of alkynes
would be an effective complement to the method of
constructing alkenyl thiocyanate structures.
ubiquitous presence in natural products like alkaloids1 and
huge application in organic synthesis as precursors.2 Electro-
philic thiocyanation has been proven to be an effective and
remarkable way to synthesize thiocyanates. Our group have
developed some electrophilic thiocyanation reagents3 with
appreciable reactivity which successfully achieved the thiocya-
nation of ketones, aromatic compounds, and olefins (Scheme
1).3,4 However, in most of these reactions that have been
reported, electrophilic thiocyanation reagents are only used as
the source of SCN, while the other part of the reagents is
wasted, which is not satisfying to the requirements of atom
economy. Although alkenyl thiocyanate has versatile trans-
formation capabilities in synthetic chemistry, the method for
At the same time, for the irreplaceable role of amines in
medicinal chemistry and agricultural chemistry, regioselective
introduction of an amino group is an eternal topic for scholars
and engineers,6 and amination of alkynes is an ideal way to
introduce amino groups to organics.7 Bifunctionalization is a
powerful tool to construct various organic compounds, for it
can flexibly introduce various functional groups with high atom
utilization.8 Therefore, it will be very fascinating if the
bifunctionalization of alkynes can be completed using an
electrophilic thiocyanation reagent to simultaneously construct
C(sp2)−SCN and C(sp2)−N bonds. NTSI reported by us3c
and the Chen group4e recently was chosen to develop the
difunctionalization of alkynes because it is an efficient
electrophilic thiocyanato reagent reacting with indoles, ani-
lines, and phenols in a high yield. Obviously, control of
regioselectivity is still an unignorable challenge, and thiocya-
nation on benzene rings is also a competitive reaction.
Scheme 1. Applications of N-SCN Reagents
Received: November 19, 2020
Published: March 11, 2021
https://dx.doi.org/10.1021/acs.joc.0c02780
© 2021 American Chemical Society
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Note
a b
,
Moreover, the product could be easily converted to 2-
aminothiazoles.9
Scheme 2. Scope of Substrates
As far as we know, the distal end of the triple bond of 1-
methoxy-4-(phenylethynyl)benzene has higher electron den-
sity,10 and among the reagents in hand, NTSI has a
considerable reactivity, so we embarked upon our investigation
of the reaction of 1-methoxy-4-(phenylethynyl)benzene (1a)
and NTSI. To our delight, the desired difunctional product
(2a) was facilely obtained in 91% yield at room temperature
(Table 1, entry 1). But slightly reduced results were obtained
Table 1. Optimization of the Difunctionalization Reaction
a
Conditions
b
c
entry variation from the standard conditions yield (%)
ratio Z/E
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
none
91
78
75
88
85
69
32
54
27
67
25
73
23
44
trace
trace
trace
77
7:1
7:1
7:1
7:1
6:1
7:1
8:1
7:1
7:1
7:1
8:1
6:1
7:1
8:1
increasing NTSI to 2.5 equiv
decreasing NTSI to 1.5 equiv
adding Zn(OTf)2 (0.2 equiv)
adding Zn(OTf)2 (3 equiv)
adding Me3SiCl (0.2 equiv)
adding Me3SiCl (3 equiv)
adding Me3SiOTf (0.2 equiv)
adding Me3SiOTf (3 equiv)
adding TfOH (0.2 equiv)
adding TfOH (3 equiv)
CH2ClCH2Cl instead of CH2Cl2
THF instead of CH2Cl2
CH3CN instead of CH2Cl2
DMF instead of CH2Cl2
DMSO instead of CH2Cl2
CH3OH instead of CH2Cl2
0 °C instead of rt
a
Reaction conditions: 1a−x (0.1 mmol, 1.0 equiv), NTSI (0.2 mmol,
b
2.0 equiv), CH2Cl2 (1.0 mL), room temperature, 5 h, Ar. Isolated
yield; Z/E ratios were determined by H NMR analysis.
1
methoxy to hydroxyl (2l), ethoxy (2o−t), phenoxy (2u),
benzyloxy (2v, 2w) and NHBoc (2x). To our delight, all of
them proceeded smoothly with the bifunctionalized products
in good to excellent yields, which greatly broadened the
application value. Furthermore, a heteroaryl substituent was
successfully converted to the corresponding product in 79%
yield (2y).
8:1
a
Reaction conditions: 1a (0.1 mmol, 1.0 equiv), NTSI (0.2 mmol, 2.0
b
c
equiv), solvent (1.0 mL), 5 h, Ar. Isolated yield. Determined by 1H
NMR.
when the loading of NTSI was increased or decreased (Table
1, entries 2 and 3). Considering that the acid (Lewis acid and
Bronsted acid) may have an activating effect on the reagent,
adding acids (catalytic and excessive amount) was carried out,
but giving 2a in lower yields (Table 1, entries 4−11).
Meanwhile, we also screened other solvents such as
CH2ClCH2Cl, THF, CH3CN, DMF, DMSO, and CH3OH
(Table 1, entries 12−17), respectively. But we did not get
better results. And low temperature resulted in a lower
conversion (Table 1, entry 18).
Most of products show the good selectivity of configuration
1
from 2:1 to 20:1 according to H NMR. In order to ascertain
the dominant configuration of this reaction, the structure of 2v
was confirmed by X-ray crystal structure analysis and proved it
to be a Z-isomer (Figure 1). It is easy to infer that other
After obtaining the optimal reaction conditions, the
applicability of the reaction was tested by enlarging the
substrate scope. The reactivity of aryl alkynes is stated in
Scheme 2. First, a series of thiocyanation-amination of alkynes
with electron-withdrawing or electron-donating substituents at
the para position of phenol were obtained in good to excellent
yields (2b−k). m-Substituted (2i) and o-substituted (2j, 2k)
alkynes were also got in moderate yields. Moreover, this
protocol was proved to be unlimited to diphenylacetylene since
substrates like 1m−n were tested and got an acceptable yield.
Encouraged by the above results, we shifted the attention from
Figure 1. X-ray crystal structure of 2v.
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Note
products are also Z-selective or a single Z-isomer (2e, 2l, 2n,
2s) based on the same rule of the chemical shifts of
characteristic hydrogen such as the ortho-hydrogen of sulfonyl.
The X-ray crystallographic study of E-2q, 2n, and 2s was also
carried out to further confirm our inference (see Supporting
Information). It should be noted that the o-substituted alkynes
(2j, 2k, 2t) exhibit significant stereoselectivity (Z/E = 20:1).
Only phenylpropyne (1m) shows more preference to the E-
isomer. On the basis of the crystal structure, the existence of
the π−π stacking interaction between two aromatic rings might
greatly enhance Z-selectivity while 1n might be owing to the
repulsion between the free radical orbital and C−H σ-bonds of
trimethylsilyl.
Scheme 5. Control Experiments
was detected with HRMS (calcd for C16H24NOS [M + H]+:
278.1573, found: 278.1566). All suggested that this reaction
involved a free radical reaction mechanism.
On the basis of the above results and other references,12 the
possible Z-selective reaction mechanism is proposed in Scheme
6. The reaction is initiated by alkynes with NTSI to generate
To compare the order of the reactivity of the NTSI reagent
toward alkyne, alkene, and α-position of ketone, 1za bearing
alkyne and ketone and 1zb bearing alkyne and alkene were
chosen to react with NTSI. Satisfyingly, only 2z was obtained
in undiminished yield (Scheme 3).
Scheme 6. Proposed Reaction Mechanism
Scheme 3. Function Group Tolerance of NTSI towards
Alkyne, Alkene, and Active Protons
ethylenic free radical II, and π−π stacking interaction of the
aromatic rings of the substrate facilitates the conversion from
II to more stable III. The intermediates (II and III)
subsequently delivered the desired product with two isomers.
In summary, with simple and mild reaction conditions, we
successfully constructed C−S and C−N bonds in one step to
generate aminated vinyl thiocyanates by N-thiocyanato-
dibenzenesulfonimide with good yield and great application
prospects. As far as we know, this study provides the first
example of thiocyanation-amination of alkynes by intermo-
lecular bifunctionalization, which is an important supplement
to the limited methods of intermolecular alkyne amination and
constructing alkenyl thiocyanate structures.
In order to prove the practicality of this reaction, a gram-
scale reaction of 1o was carried out with similar yield and
diastereoselectivity (Scheme 4a). Subsequently, the desulfony-
Scheme 4. Gram Scale of Bifunctionalization of Alkyne and
Desulfonylation of 2o
EXPERIMENTAL SECTION
■
General Experimental Information. All reactions were carried
out under an argon atmosphere, unless otherwise stated. All chemicals
were purchased from Acros, Alfa, Aladdin, or InnoChem and used as
they come unless otherwise stated. Thin-layer chromatography
(TLC) was performed on silica gel F254 TLC glass plates and
visualized with UV light. Solvents like petroleum ether (PE) and ethyl
acetate (EA) were used directly in column chromatography. THF was
dried over sodium (diphenyl ketone) and distilled and stored in
lation of 1o was performed, and the amino product (3o) was
obtained in 81% yield (Scheme 4b), which is an important
precursor for the synthesis of thiazole and azirine.9
To elucidate the reaction mechanism, the control experi-
ment was carried out (Scheme 5). The transformation was
greatly inhibited to 23% yield with 2.0 equiv of 2,2,6,6-
tetramethyl-1-piperidinyloxy (TEMPO), whereas 20 mol % of
it gave 85% yield. Further, the trapping experiment was carried
out with butylated hydroxytoluene (BHT) under standard
reaction conditions, and the free radical adduct (C16H23NOS)
1
Schlenk reservoir; CH2Cl2 was distilled over CaH2 before use. H
NMR spectra were recorded on a Bruker Avance400 (400 MHz)
spectrometer or Bruker Avance700 (700 MHz) spectrometer, and all
signals are reported in ppm with the internal chloroform signal at 7.26
ppm or acetone signal at 2.05 ppm as the standard. 13C{1H} NMR
spectra were recorded on a Bruker Avance400 (100 MHz)
spectrometer or Bruker Avance700 (175 MHz) spectrometer, and
all signals are reported in ppm with the internal chloroform signal at
77.0 ppm or acetone signal at 206.4 and 29.7 ppm as the standard.
High resolution mass spectrum (HRMS): AGILENT Q-TOF 6520.
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Note
General Procedure A for Synthesis of 1.11 The corresponding
aryl iodide (1.0 mmol), Pd(PPh3)2Cl2 (1−2 mol %), CuI (1 mol %),
PPh3 (1−2 mol %), and phenylacetylene (1.3 equiv) were added to a
250 mL Schlenk flask with a stir bar under Ar. Then THF (80 mL)
and Et3N (80 mL) were added sequentially. The reaction mixture was
then stirred at room temperature overnight. Then, 60 mL of water
was added and the reaction mixture was extracted with EtOAc (3 ×
15 mL), washed with brine, and dried over MgSO4. After filtration,
the solvent was removed under reduced pressure. The residue was
purified by silica gel column chromatography using PE and EtOAc as
the eluent.
General Procedure B for Synthesis of 2. To a Schlenk tube
containing alkynes was added, alkynes (0.1 mmol, 1.0 equiv) was
added CH2Cl2 (1.0 mL) under an argon atmosphere. Then, NTSI
(0.2 mmol, 2.0 equiv) was added. The reaction was stirred at room
temperature for 5 h. The reaction mixture was purified by column
chromatography on silica gel with petroleum ether/ethyl acetate (8:1,
v/v) to afford the pure desired product.
= 8.0 Hz, 1H), 7.04 (s, 1H), 6.88−6.84 (m, 3H), 4.04 (q, J = 7.2 Hz,
2H), 3.81 (s, J = 7.2 Hz, 3H), 1.42 (t, J = 7.2 Hz, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 159.4, 159.1, 133.1, 129.4, 124.7, 124.1,
116.2, 115.1, 114.6,114.6, 89.3, 88.0, 63.5, 55.3, 14.8 ppm. HRMS
(ESI), m/z: calcd for C17H17O2 [M + H]+: 253.1223, found:
253.1230.
1-((4-Ethoxyphenyl)ethynyl)-2-fluorobenzene (1t). 1t was synthe-
sized following the general procedure A: white solid (204 mg, 85%
yield), eluent PE/EtOAc (49:1, v/v); 1H NMR (400 MHz, CDCl3) δ
7.51−7.46 (m, 3H), 7.30−7.26 (m, 1H), 7.09 (q, J = 8.0 Hz, 2H),
6.86 (d, J = 8.8 Hz, 2H), 4.05 (q, J = 6.8 Hz, 2H), 1.42 (t, J = 6.8 Hz,
3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 162.5 (C−F, 1JC−F
=
3
249.4 Hz), 159.3, 133.3, 129.5 (C−F, JC−F = 7.9 Hz), 123.9 (C−F,
4JC−F = 3.7 Hz), 115.5 (C−F, 2JC−F = 21 Hz), 114.9, 114.5, 112.3 (C−
F, 2JC−F = 15.9 Hz), 94.6 (C−F, 4JC−F = 3.2 Hz), 81.3, 63.6, 14.7 ppm.
HRMS (ESI), m/z: calcd for C16H14FO [M + H]+: 241.1023, found:
241.1031.
1-(Benzyloxy)-4-(phenylethynyl)benzene (1v). 1v was synthesized
Procedure C for Synthesis of 3o. Under an argon atmosphere,
to a mixture of 2o (1.7 mmol, 1.0 equiv) and Mg powder (17.0 mmol,
10 equiv) in THF (30 mL) were added Ti(O-i-Pr)4 (3.4 mmol, 2.0
equiv) and Me3SiCl (5.1 mmol, 3.0 equiv). The resulting mixture was
stirred at 60 °C with a heating mantle. After checking consumption of
the substrate by TLC analysis, the mixture was filtered through a pad
of Celite. The solvent was removed under reduced pressure by an
aspirator; then the reaction mixture was purified by column
chromatography on silica gel with petroleum ether/ethyl acetate
(4:1, v/v) to afford the pure desired product.
Gram-Scale Reaction. Following the general procedure B, to a
glass reaction flask containing 1o (4.5 mmol, 1.0 equiv) was added
CH2Cl2 (35 mL) under an argon atmosphere. Then, NTSI (9.0
mmol, 2.0 equiv) was added. The reaction was stirred at room
temperature for 5 h. The reaction mixture was purified by column
chromatography on silica gel with petroleum ether/ethyl acetate (8:1,
v/v) to afford 2o as a white solid (2.6 g, 83% yield).
following the general procedure A: white solid (253 mg, 89% yield),
eluent PE/EtOAc (49:1, v/v); H NMR (400 MHz, CDCl3) δ 7.50
(dd, J = 7.6, 1.6 Hz, 2H), 7.46 (d, J = 8.8 Hz, 2H), 7.43−7.28 (m,
8H), 6.94 (d, J = 8.4 Hz, 2H), 5.08 (s, 2H) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 158.8, 136.7, 133.1, 131.5, 128.6, 128.3, 128.1, 128.0,
127.5, 123.6, 115.7, 115.0, 89.4, 88.2, 70.1 ppm. HRMS (ESI), m/z:
calcd for C21H17O [M + H]+: 285.1274, found: 285.1280.
1
1-(Benzyloxy)-4-((4-fluorophenyl)ethynyl)benzene (1w). 1w was
synthesized following the general procedure A: white solid (239 mg,
78% yield), eluent PE/EtOAc (49:1, v/v); 1H NMR (400 MHz,
CDCl3) δ 7.49−7.31 (m, 9H), 7.02 (t, J = 8.8 Hz, 2H), 7.94 (d, J =
8.8 Hz, 2H), 5.08 (s, 2H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ
162.4 (C−F, 1JC−F = 247.6 Hz), 158.9, 136.6, 133.3 (C−F, 3JC−F = 8.2
4
Hz), 128.6, 128.1, 127.5, 119.7 (C−F, JC−F = 3.5 Hz), 115.6 (C−F,
2JC−F = 21.9 Hz), 115.5, 115.0, 89.0, 87.1, 70.1 ppm. HRMS (ESI),
m/z: calcd for C21H16FO [M + H]+: 303.1180, found: 303.1190.
N-(4-(Phenylethynyl)phenyl)-O-pivaloylhydroxylamine (1x). 1x
was synthesized following the general procedure A: yellow solid (228
1-Ethoxy-4-((4-fluorophenyl)ethynyl)benzene (1p). 1p was syn-
thesized following the general procedure A: white solid (202 mg, 84%
yield), eluent PE/EtOAc (49:1, v/v); 1H NMR (400 MHz, CDCl3) δ
7.49−7.46 (m, 2H), 7.44 (d, J = 8.8 Hz, 2H), 7.02 (t, J = 8.8 Hz, 2H),
6.86 (d, J = 8.8 Hz, 2H), 4.04 (q, J = 6.8 Hz, 2H), 1.42 (t, J = 6.8 Hz,
1
mg, 78% yield), eluent PE/EtOAc (20:1, v/v); H NMR (400 MHz,
CDCl3) δ 7.52−7.49 (m, 2H), 7.46 (d, J = 8.8 Hz, 2H), 7.36−7.30
(m, 5H), 6.52 (s, 1H), 1.52 (s, 9H) ppm. 13C{1H} NMR (100 MHz,
CDCl3) δ 152.4, 138.5, 132.5, 131.5, 128.3, 128.0, 123.5, 118.1, 117.6,
89.3, 88.6, 80.9, 28.3 ppm. HRMS (ESI), m/z: calcd for C19H20NO2
[M + H]+: 294.1489, found: 294.1497.
3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 162.3 (C−F, 1JC−F
=
3
247.4 Hz), 159.1, 133.3 (C−F, JC−F = 8.1 Hz), 133.0, 119.8 (C−F,
2
4JC−F = 3.5 Hz), 115.6 (C−F, JC−F = 21.9 Hz), 115.0, 114.6, 89.1,
(Z)-N-(1-(4-Methoxyphenyl)-2-phenyl-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2a). 2a was synthesized
following the general procedure B: white solid (51 mg, 91% yield,
86.9, 63.5, 14.7 ppm. HRMS (ESI), m/z: calcd for C16H14FO [M +
H]+: 241.1023, found: 241.1030.
1
1-Ethoxy-4-((4-nitrophenyl)ethynyl)benzene (1q). 1q was synthe-
sized following the general procedure A: yellow solid (221 mg, 83%
yield), eluent PE/EtOAc (49:1, v/v); 1H NMR (400 MHz, CDCl3) δ
8.20 (d, J = 8.8 Hz, 2H), 7.62 (d, J = 8.8 Hz, 2H), 7.48 (d, J = 8.8 Hz,
2H), 6.89 (d, J = 8.8 Hz, 2H), 4.07 (q, J = 7.2 Hz, 2H), 1.43 (t, J = 7.2
Hz, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 159.9, 146.7,
133.4, 132.0, 130.8, 123.6, 114.7, 113.9, 95.3, 86.6, 63.6, 14.7 ppm.
HRMS (ESI), m/z: calcd for C16H14NO3 [M + H]+: 268.0968, found:
268.0971.
mixture of 7:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); H NMR
(400 MHz, CDCl3) δ 7.94 (d, J = 7.6 Hz, 4H), 7.60−7.56 (t, J = 7.6
Hz, 2H), 7.45−7.41 (m, 6H), 7.32−7.31 (m, 3H), 7.08 (d, J = 8.8 Hz,
2H), 6.41 (d, J = 8.8 Hz, 2H), 3.67 (s, 3H) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 159.9, 139.5, 135.5, 135.4, 134.3, 134.1, 133.3, 130.5.
130.0, 129.3, 129.0, 128.8, 127.1, 113.5, 109.4, 55.2 ppm. IR (KBr)
2920, 2848, 2160 (SCN), 1508, 1379, 1259, 1168, 750 cm−1. HRMS
(ESI), m/z: calcd for C28H22KN2O5S3 [M + K]+: 601.0322, found:
601.0316.
1-((4-Ethoxyphenyl)ethynyl)-3-fluorobenzene (1r). 1r was synthe-
sized following the general procedure A: white solid (199 mg, 83%
yield), eluent PE/EtOAc (49:1, v/v); 1H NMR (400 MHz, CDCl3) δ
7.45 (d, J = 8.8 Hz, 2H), 7.31−7.26 (m, 2H), 7.21−7.18 (m, 1H),
7.03−6.97 (m, 1H), 6.86 (d, J = 8.8 Hz, 2H), 4.05 (q, J = 7.2 Hz,
2H), 1.42 (t, J = 7.2 Hz, 3H) ppm. 13C{1H} NMR (100 MHz,
CDCl3) δ 162.5 (C−F, 1JC−F = 244.4 Hz), 159.3, 133.2, 129.8 (C−F,
N-(1-(4-Methoxyphenyl)-2-(4-nitrophenyl)-2-thiocyanatovinyl)-
N-(phenylsulfonyl)benzenesulfonamide (2b). 2b was synthesized
following the general procedure B: yellow solid (52 mg, 85% yield,
mixture of 1.8:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 8.16 (d, J = 8.8 Hz, 2H), 7.94 (d, J =
7.6 Hz, 4H), 7.63−7.58 (m, 4H), 7.44 (t, J = 7.6 Hz, 4H), 7.07 (d, J =
8.8 Hz, 2H), 6.44 (d, J = 9.2 Hz, 2H), 3.69 (s, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 160.7, 147.9, 142.1, 139.2, 138.9, 134.4,
133.6, 131.6, 130.9, 129.2, 129.0, 126.1, 124.3, 113.9, 108.8, 55.4
4
3
3JC−F = 8.7 Hz), 127.3 (C−F, JC−F = 2.9 Hz), 125.6 (C−F, JC−F
=
2
2
9.5 Hz), 118.2 (C−F, JC−F = 22.5 Hz), 115.2 (C−F, JC−F = 21.1
Hz), 114.7, 114.6, 90.5, 86.8 (C−F, 4JC−F = 3.2 Hz), 63.6, 14.7 ppm.
HRMS (ESI), m/z: calcd for C16H14FO [M + H]+: 241.1023, found:
241.1028.
1
ppm. E-isomer: H NMR (400 MHz, CDCl3) δ 7.97 (d, J = 8.8 Hz,
2H), 7.86 (d, J = 8.8 Hz, 2H), 7.63−7.58 (overlap with Z, 2H), 7.49
(d, j = 7.6 Hz, 4H), 7.46−7.42 (overlap with Z, 2H), 7.20 (t, J = 8.0
Hz, 4H), 6.81 (d, J = 8.8 Hz, 2H), 3.85 (s, 3H) ppm. 13C{1H} NMR
(100 MHz, CDCl3) δ 161.3, 148.2, 140.3, 139.0, 138.0, 133.7, 133.1,
131.6, 130.1, 128.8, 128.4, 125.9, 123.9, 114.3, 108.5, 55.6 ppm. IR
(KBr) 2931, 2843, 2160 (SCN), 1508, 1379, 1346, 1261, 1168, 750
1-((4-Ethoxyphenyl)ethynyl)-3-methoxybenzene (1s). 1s was
synthesized following the general procedure A: white solid (199
1
mg, 79% yield), eluent PE/EtOAc (49:1, v/v); H NMR (400 MHz,
CDCl3) δ 7.45 (d, J = 9.2 Hz, 2H), 7.22 (d, J = 8.0 Hz, 1H), 7.10 (d, J
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Note
cm−1. HRMS (ESI), m/z: calcd for C28H21KN3O7S3 [M + K]+:
646.0173, found: 646.0167.
N-(2-(4-Fluorophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2c). 2c was synthesized
following the general procedure B: white solid (46 mg, 79% yield,
mixture of 4:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 4H), 7.61−7.57
N-(2-(4-Cyanophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2g). 2g was synthesized
following the general procedure B: yellow solid (48 mg, 81% yield,
mixture of 2:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 4H), 7.62−7.42
(overlap with E, 10H), 7.05 (d, J = 8.8 Hz, 2H), 6.44 (d, J = 8.8 Hz,
2H), 3.70 (s, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.6,
139.2, 138.9, 138.4, 134.4, 133.5, 132.8, 131.2, 130.8, 129.2, 128.9,
126.2, 118.0, 114.2, 113.8, 108.8, 55.4 ppm. E-isomer: 1H NMR (400
MHz, CDCl3) δ 7.82 (d, J = 8.4 Hz, 2H), 7.62−7.42 (overlap with Z,
10H), 7.24 (t, J = 8.4 Hz, 4H), 6.79 (d, J = 8.8 Hz, 2H), 3.85 (s, 3H)
ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 161.3, 140.2, 138.6, 137.5,
133.8, 133.1, 132.5, 131.2, 130.7, 128.8, 128.4, 125.9, 117.9, 113.7,
113.3, 108.8, 55.5 ppm. IR (KBr) 2924, 2850, 2229, 2160 (SCN),
1602, 1508, 1379, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C29H21KN3O5S3 [M + K]+: 626.0275, found: 626.0280.
(overlap with E, 2H), 7.49−7.42 (overlap with E, 6H), 7.07 (d, J = 8.8
Hz, 2H), 7.01 (t, J = 8.4 Hz, 2H), 6.43 (d, J = 8.8 Hz, 2H), 3.69(s,
3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 163.3 (C−F, 1JC−F
=
250.7 Hz), 160.0, 139.4, 135.8, 134.2, 133.3, 133.0, 132.6 (C−F, 3JC−F
4
= 8.6 Hz), 131.4 (C−F, JC−F = 3.4 Hz), 129.2, 128.8, 126.9, 116.4
2
1
(C−F, JC−F = 22 Hz), 113.6, 109.3, 55.3 ppm. E-isomer: H NMR
(400 MHz, CDCl3) δ 7.72−7.69 (m, 2H), 7.61−7.57 (overlap with Z,
2H), 7.49−7.42 (overlap with Z, 6H), 7.23 (t, J = 8.0 Hz, 4H), 6.91
(t, J = 8.8 Hz, 2H), 6.78 (d, J = 8.8 Hz, 2H), 3.84 (s, 3H) ppm.
13C{1H} NMR (100 MHz, CDCl3) δ 160.9, 139.2, 133.5, 133.1, 132.3
Ethyl-4-(2-(4-methoxyphenyl)-2-(N-(phenylsulfonyl)-
phenylsulfonamido)-1-thiocyanatovinyl)benzoate (2h). 2h was
synthesized following the general procedure B: white solid (48 mg,
76% yield, mixture of 3.2:1 Z:E isomers), eluent PE/EtOAc (8:1, v/
3
2
(C−F, JC−F = 8.6 Hz), 128.3, 116.1 (C−F, JC−F = 21.9 Hz), 114.1,
55.5 ppm. IR (KBr) 2922, 2843, 2160 (SCN), 1508, 1379, 1257,
1168, 750 cm−1. HRMS (ESI), m/z: calcd for C28H25FN3O5S3 [M +
NH4]+: 598.0935, found: 598.0925.
1
v); Z-isomer: H NMR (400 MHz, CDCl3) δ 7.98 (d, J = 8.0 Hz,
2H), 7.94 (d, J = 7.6 Hz, 4H), 7.59 (t, J = 7.6 Hz, 2H), 7.51 (d, J = 8.4
Hz, 2H), 7.44 (t, J = 7.6 Hz, 4H), 7.07 (d, J = 8.8 Hz, 2H), 6.41 (d, J
= 8.8 Hz, 2H), 4.36 (q, J = 7.2 Hz, 2H), 3.69 (s, 3H), 1.38 (t, J = 7.2
Hz, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 165.7, 160.3,
139.4, 139.1, 137.1, 134.2, 133.4, 132.3, 131.5, 130.5, 130.1, 129.2,
N-(1-(4-Methoxyphenyl)-2-thiocyanato-2-(m-tolyl)vinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2d). 2d was synthesized
following the general procedure B: white solid (49 mg, 85% yield,
mixture of 5.6:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 8.0 Hz, 4H), 7.57 (t, J =
7.6 Hz, 2H), 7.43 (t, J = 7.6 Hz, 4H), 7.33 (d, J = 8.0 Hz, 2H), 7.12−
7.08 (m, 4H), 6.41 (d, J = 8.8 Hz, 2H), 3.67 (s, 3H), 2.31 (s, 3H)
ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 159.8, 140.3, 139.5, 134.6,
134.1, 133.2, 132.5, 130.4, 129.8, 129.2, 128.8, 127.4, 113.5, 109.6,
55.2, 21.3 ppm. E-isomer: 1H NMR (400 MHz, CDCl3) δ 7.62−7.55
(overlap with Z, 4H), 7.44−7.41 (overlap with E, 6H), 7.17 (t, J = 8.0
Hz, 4H), 7.03 (d, J = 8.8 Hz, 2H), 6.76 (d, J = 8.8 Hz, 2H), 3.82 (s,
3H), 2.31 (s, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.8,
139.3, 133.1, 132.9, 130.0, 129.7, 128.9, 128.1, 126.8, 114.1, 109.2,
55.5, 21.4 ppm. IR (KBr) 3132, 2922, 2848, 2160 (SCN), 1602, 1508,
1402, 1257, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C29H28N3O5S3 [M + NH4]+: 594.1186, found: 594.1184.
(Z)-N-(2-(4-Ethylphenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2e). 2e was synthesized
following the general procedure B: white solid (41 mg, 71% yield),
eluent PE/EtOAc (8:1, v/v); 1H NMR (400 MHz, CDCl3) δ 7.93 (d,
J = 8.0 Hz, 4H), 7.58 (t, J = 7.2 Hz, 2H), 7.43 (t, J = 8.0 Hz, 4H),
7.35 (d, J = 8.0 Hz, 2H), 7.13 (d, J = 8.4 Hz, 2H), 7.09 (d, J = 8.8 Hz,
2H), 6.41 (d, J = 8.8 Hz, 2H), 3.68 (s, 3H), 2.62 (q, J = 7.6 Hz, 2H),
1.21 (t, J = 7.6 Hz, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ
159.7, 146.4, 139.5, 134.7, 134.6, 134.1, 133.2, 132.6, 130.5, 129.2,
128.8, 128.5, 127.4, 113.4, 109.6, 55.2, 28.7, 14.9 ppm. IR (KBr)
2922, 2850, 2160 (SCN), 1602, 1508, 1379, 1259, 1168, 750 cm−1.
HRMS(ESI), m/z: calcd for C30H26KN2O5S3 [M + K]+: 629.0635,
found: 629.0643.
1
128.9, 126.7, 113.7, 109.0, 61.3, 55.3, 14.3 ppm. E-isomer: H NMR
(400 MHz, CDCl3) δ 7.87(d, J = 8.4 Hz, 2H), 7.77 (d, J = 8.4 Hz,
2H), 7.61−7.57 (overlap with Z, 2H), 7.46−7.40 (overlap with Z,
6H), 7.18 (t, J = 7.6 Hz, 4H), 6.79 (d, J = 7.6 Hz, 2H), 4.43 (q, J = 7.2
Hz, 2H), 3.85 (s, 3H), 1.44 (t, J = 7.2 Hz, 3H) ppm. 13C{1H} NMR
(100 MHz, CDCl3) δ 165.6, 161.1, 139.9, 138.3, 136.0, 133.1, 132.8,
131.8, 130.0, 130.0, 128.8, 128.3, 126.3, 114.2, 108.7, 61.2, 55.5, 14.4
ppm. IR (KBr) 2922, 2848, 2160 (SCN), 1716, 1508, 1379, 1259,
1168, 750 cm−1. HRMS (ESI), m/z: calcd for C31H26KN2O7S3 [M +
K]+: 673.0534, found: 673.0536.
N-(2-(3-Fluorophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2i). 2i was synthesized
following the general procedure B: white solid (45 mg, 78% yield,
mixture of 3.5:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 4H), 7.60−7.56
(t, J = 7.6 Hz, 2H), 7.43 (t, J = 7.6 Hz, 4H), 7.34−7.26 (overlap with
E, 1H), 7.24−7.15 (overlap with E, 2H), 7.09 (d, J = 8.8 Hz, 2H),
7.02−6.98 (m, 1H), 6.43 (d, J = 8.8 Hz, 2H), 3.67 (s, 3H) ppm.
13C{1H} NMR (175 MHz, CDCl3) δ 162.7 (C−F, 1JC−F = 246.9 Hz),
160.2, 139.3, 137.6 (C−F, 3JC−F = 7.9 Hz), 136.8, 134.3, 133.3, 132.4,
130.8 (C−F, 3JC−F = 8.0 Hz), 129.2, 128.9, 126.7, 126.4, 117.4 (C−F,
2
2JC−F = 22.9 Hz), 117.1 (C−F, JC−F = 20.8 Hz), 113.7, 109.1, 55.3
1
ppm. E-isomer: H NMR (400 MHz, CDCl3) δ 7.60−7.56 (overlap
with Z, 3H), 7.48−7.46 (m, 6H), 7.34−7.26 (overlap with Z, 2H),
7.24−7.15 (overlap with Z, 4H), 6.91−6.87 (m, 1H), 6.78 (d, J = 8.8
Hz, 2H), 3.83 (s, 3H) ppm. 13C{1H} NMR (175 MHz, CDCl3) δ
162.4 (C−F, 1JC−F = 246.6 Hz), 161.0, 139.1, 136.2 (C−F, 3JC−F = 7.9
N-(2-(2-Chlorophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2f). 2f was synthesized
following the general procedure B: white solid (43 mg, 72% yield,
mixture of 2.7:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 4H), 7.58 (t, J =
3
Hz), 135.7, 133.6, 133.1, 132.0, 130.5 (C−F, JC−F = 8.1 Hz), 128.8,
128.3, 125.9, 114.2, 108.7, 55.5 ppm. IR (KBr) 2926, 2850, 2160
(SCN), 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI), m/z: calcd
for C28H25FN3O5S3 [M + NH4]+: 598.0935, found: 598.0925.
N-(1-(4-Ethoxyphenyl)-2-(2-fluorophenyl)-2-thiocyanatovinyl)-
N-(phenylsulfonyl)benzenesulfonamide (2j). 2j was synthesized
following the general procedure B: white solid (41 mg, 70% yield,
mixture of 20:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 7.2 Hz, 4H), 7.60 (t, J =
7.6 Hz, 2H), 7.43 (t, J = 7.6 Hz, 4H), 7.38 (d, J = 8.8 Hz, 2H), 7.29
(d, J = 8.4 Hz, 2H), 7.07 (d, J = 8.8 Hz, 2H), 6.43 (d, J = 8.8 Hz, 2H),
3.69 (s, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.1, 139.3,
136.3, 136.0, 134.2, 133.3, 133.0, 132.8, 131.8, 129.4, 129.2, 128.9,
126.8, 113.7, 109.2, 55.3 ppm. E-isomer: 1H NMR (400 MHz,
CDCl3) δ 7.64 (d, J = 8.4 Hz, 2H), 7.60−7.56 (overlap with Z, 2H),
7.50−7.41 (overlap with Z, 6H), 7.23 (t, J = 8.0 Hz, 4H), 7.16 (d, J =
8.4 Hz, 2H), 6.78 (d, J = 8.8 Hz, 2H), 3.83 (s, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 161.0, 139.1, 136.4, 135.4, 133.9, 133.5,
132.4, 132.2, 131.4, 128.8, 128.3, 126.4, 114.1, 108.8, 55.5 ppm. IR
(KBr) 2920, 2848, 2158 (SCN), 1602, 1508, 1379, 1257, 1168, 750
cm−1. HRMS (ESI), m/z: calcd for C28H21ClKN2O5S3 [M + K]+:
634.9933, found: 634.9928.
7.6 Hz, 2H), 7.45 (t, J = 7.6 Hz, 4H), 7.41−7.31 (m, 2H), 7.16 (d, J =
8.8 Hz, 2H), 7.14−7.03 (m, 2H), 6.46 (d, J = 8.8 Hz, 2H), 3.69 (s,
3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.3 (C−F, 1JC−F
=
251.5 Hz), 159.7, 139.4, 138.1, 134.2, 132.5, 132.2 (C−F, 3JC−F = 8.3
4
Hz), 131.9 (C−F, JC−F = 1.6 Hz), 129.3, 128.9, 128.4, 127.0, 124.8
4
2
(C−F, JC−F = 3.6 Hz), 123.5 (C−F, JC−F = 13.7 Hz), 116.4 (C−F,
2JC−F = 20.9 Hz), 113.5, 108.9, 55.3 ppm. IR (KBr) 2920, 2838, 2160
5331
https://dx.doi.org/10.1021/acs.joc.0c02780
J. Org. Chem. 2021, 86, 5327−5335

The Journal of Organic Chemistry
pubs.acs.org/joc
Note
(SCN), 1602, 1508, 1379, 1255, 1168, 752 cm−1. HRMS (ESI), m/z:
calcd for C28H25FN3O5S3 [M + NH4]+: 598.0935, found: 598.0925.
N-(2-(2-Chlorophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2k). 2k was synthesized
following the general procedure B: white solid (39 mg, 65% yield,
mixture of 18:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 8.12 (d, J = 7.6 Hz, 2H), 7.85 (d, J =
7.6 Hz, 2H), 7.65 (t, J = 7.6 Hz, 1H), 7.55−7.51 (m, 3H), 7.42−7.35
(m, 4H), 7.30−7.22 (m, 2H), 7.19 (d, J = 8.8 Hz, 2H), 6.45 (d, J =
8.8 Hz, 2H), 3.67 (s, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ
160.2, 139.8, 138.9, 138.1, 134.4, 134.1, 132.2, 132.1, 131.2, 130.4,
129.6, 129.2, 128.9, 128.7, 127.4, 113.5, 108.7, 55.2 ppm. E-isomer:
13C{1H} NMR (100 MHz, CDCl3) δ 134.4, 134.1, 131.9, 126.8 ppm.
129.0, 128.9, 126.4, 114.5, 109.1, 63.7, 14.8 ppm. IR (KBr) 3120,
3012, 2160 (SCN), 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI),
m/z: calcd for C29H24KN2O5S3 [M + K]+: 615.0479, found: 615.0475.
N-(1-(4-(Benzyloxy)phenyl)-2-(4-fluorophenyl)-2-thiocyanato-
vinyl)-N-(phenylsulfonyl)benzenesulfonamide (2p). 2p was synthe-
sized following the general procedure B: white solid (54 mg, 88%
yield, mixture of 2.6:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-
isomer: 1H NMR (400 MHz, CDCl3) δ 7.91 (d, J = 7.6 Hz, 4H,), 7.53
(t, J = 7.6 Hz, 2H), 7.47−7.35 (overlap with E, 11H), 7.05 (d, J = 8.4
Hz, 2H), 7.01 (t, J = 8.4 Hz, 2H), 6.50 (d, J = 9.2 Hz, 2H), 3.90 (q, J
= 6.8 Hz, 2H), 1.36 (t, J = 6.8 Hz, 3H) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 163.3 (C−F, 1JC−F = 250.6 Hz), 159.1, 139.4, 136.4,
135.8, 134.2, 134.0, 133.3, 132.7, 132.6 (C−F, 3JC−F = 8.6 Hz), 131.4
4
4
(C−F, JC−F = 3.4 Hz), 129.2, 128.8, 128.2 (C−F, JC−F = 2.3 Hz),
IR (KBr) 3132, 2922, 2848, 2158 (SCN), 1508, 1398, 1255, 1168,
750 cm−1. HRMS (ESI), m/z: calcd for C28H21ClKN2O5S3 [M + K]+:
634.9933, found: 634.9937.
2
127.4, 127.1, 116.4 (C−F, JC−F = 22.0 Hz), 114.5, 109.3, 69.8 ppm.
E-isomer: 1H NMR (400 MHz, CDCl3) δ 7.72−7.68(m, 2H), 7.57 (d,
J = 8.8 Hz, 2H), 7.47−7.35 (overlap with Z, 11H), 7.18 (t, J = 8.0 Hz,
4H), 6.90 (t, J = 7.2 Hz, 2H), 6.85 (d, J = 8.8 Hz, 2H), 4.06 (q, J = 6.8
Hz, 2H), 1.46 (t, J = 6.8 Hz, 3H) ppm. 13C{1H} NMR (100 MHz,
CDCl3) δ 160.0, 139.1, 136.5, 134.8, 133.5, 133.0, 132.3 (C−F, 3JC−F
= 8.7 Hz), 130.1, 128.8, 128.7, 128.3, 127.5, 126.7, 116.1 (C−F, 2JC−F
= 21.8 Hz), 115.0, 70.1 ppm. IR(KBr) 2920, 2842, 2160 (SCN),
1600, 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C34H25KFN2O5S3 [M + K]+: 695.0541, found: 695.0539.
(Z)-N-(1-(4-Hydroxyphenyl)-2-phenyl-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2l). 2l was synthesized
following the general procedure B: white solid (31 mg, 58% yield),
eluent PE/EtOAc (8:1, v/v); 1H NMR (400 MHz, CDCl3) δ 7.94 (d,
J = 7.6 Hz, 4H), 7.59(t, J = 7.2 Hz, 2H), 7.44−7.42 (m, 6H), 7.31−
7.29 (m, 3H), 7.04 (d, J = 8.8 Hz, 2H), 6.32 (d, J = 8.8 Hz, 2H), 5.14
(s, 1H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 156.2, 139.4,
135.5, 135.4, 134.5, 134.2, 133.5, 130.5, 130.0, 129.2, 129.0, 128.9,
127.3, 115.0, 109.4 ppm. IR (KBr) 3392, 3064, 2926, 2160 (SCN),
1510, 1379, 1269, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C27H24N3O5S3 [M + NH4]+: 566.0873, found: 566.0876.
N-(1-(4-Methoxyphenyl)-2-thiocyanatoprop-1-en-1-yl)-N-
(phenylsulfonyl)benzenesulfonamide (2m). 2m was synthesized
following the general procedure B: white solid (32 mg, 64% yield,
mixture of 1:1.3 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.90 (d, J = 7.2 Hz, 4H), 7.63−7.58
N-(1-(4-Ethoxyphenyl)-2-(4-nitrophenyl)-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2q). 2q was synthesized
following the general procedure B: yellow solid (53 mg, 87% yield,
mixture of 3:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 8.16 (d, J = 8.8 Hz, 2H), 7.94 (d, J =
7.6 Hz, 4H), 7.63−7.58 (overlap with E, 4H), 7.46−7,42 (overlap
with E, 4H), 7.05 (d, J = 9.2 Hz, 2H), 6.42 (d, J = 9.2 Hz, 2H), 3.90
(q, J = 6.8 Hz, 2H), 1.35 (t, J = 6.8 Hz, 3H) ppm. 13C{1H} NMR
(100 MHz, CDCl3) δ 160.1, 147.9, 142.2, 139.2, 139.0, 134.4, 133.6,
131.6, 130.7, 129.2, 128.9, 126.0, 124.3, 114.4, 108.8, 63.6, 14.6 ppm.
(overlap with E, 2H), 7.49−7.42 (overlap with E, 4H), 7.36 (d, J = 8.8
Hz, 2H), 6.73 (d, J = 8.8 Hz, 2H), 3.80 (s, 3H), 2.39 (s, 3H) ppm.
13C{1H} NMR (100 MHz, CDCl3) δ 160.4, 139.3, 135.0, 134.1,
132.5, 132.3, 129.3, 128.7, 126.5, 113.8, 109.2, 55.3, 22.3 ppm. E-
1
E-isomer: H NMR (400 MHz, CDCl3) δ 7.97 (d, J = 9.2 Hz, 2H),
7.85 (d, J = 8.8 Hz, 2H), 7.63−7.58 (overlap with Z, 2H), 7.49 (d, J =
7.6 Hz, 4H), 7.46−7.42 (overlap with Z, 2H), 7.19 (t, J = 7.6 Hz,
4H), 6.79 (d, J = 8.8 Hz, 2H), 4.07 (q, J = 6.8 Hz, 2H), 1.46 (t, J = 6.8
Hz, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.8, 148.2,
140.3, 139.0, 138.1, 133.7, 133.1, 131.6, 130.1, 128.8, 128.4, 125.7,
123.9, 114.7, 108.4, 63.8, 14.8 ppm. IR(KBr) 2983, 2920, 2850, 2160
(SCN), 1602, 1508, 1379, 1257, 1168, 750 cm−1. HRMS (ESI), m/z:
calcd for C29H23KN3O7S3 [M + K]+: 660.0330, found: 660.0329.
N-(1-(4-Ethoxyphenyl)-2-(3-fluorophenyl)-2-thiocyanatovinyl)-
N-(phenylsulfonyl)benzenesulfonamide (2r). 2r was synthesized
following the general procedure B: white solid (53 mg, 94% yield,
mixture of 4:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.94 (d, J = 7.6 Hz, 4H), 7.59 (t, J =
1
isomer: H NMR (400 MHz, CDCl3) δ 7.87 (d, J = 7.2 Hz, 4H),
7.63−7.58 (overlap with Z, 2H), 7.49−7.42 (overlap with Z, 6H),
6.85 (d, J = 8.8 Hz, 2H), 3.84 (s, 3H), 1.84 (s, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 160.9, 139.2, 134.8, 134.2, 131.9, 132.4,
128.9, 128.8, 126.4, 114.1, 108.8, 55.3, 21.4 ppm. IR (KBr) 3163,
2920, 2848, 2158 (SCN), 1604, 1508, 1379, 1255, 1168, 750 cm−1.
HRMS (ESI), m/z: calcd for C23H24N3O5S3 [M + NH4]+: 518.0873,
found: 518.0864.
(Z)-N-(1-(4-Methoxyphenyl)-2-thiocyanato-2-(trimethylsilyl)-
vinyl)-N-(phenylsulfonyl)benzenesulfonamide (2n). 2n was synthe-
sized following the general procedure B: white solid (34 mg, 64%
1
yield), eluent PE/EtOAc (8:1, v/v); H NMR (400 MHz, CDCl3) δ
7.6 Hz, 2H), 7.44 (t, J = 7.6 Hz, 4H), 7.33−7.28 (overlap with E,
1H), 7.25−7.21 (overlap with E, 1H), 7.17−7.14 (m, 1H), 7.07 (d, J
= 9.2 Hz, 2H), 7.03−6.98 (m, 1H), 6.41 (d, J = 9.2 Hz, 2H), 3.90 (q,
J = 7.2 Hz, 2H), 1.36 (t, J = 7.2 Hz, 3H) ppm. 13C{1H} NMR (100
7.85 (d, J = 7.2 Hz, 4H), 7.63 (t, J = 7.6 Hz, 2H), 7.46 (t, J = 7.6 Hz,
4H), 7.39 (d, J = 8.8 Hz, 2H), 6.77 (d, J = 8.8 Hz, 2H), 3.84 (s, 3H),
0.12 (s, 9H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 160.8, 148.8,
138.5, 134.1, 133.5, 132.5, 128.5, 128.4, 128.0, 112.8, 110.6, 54.6
ppm. IR (KBr) 2920, 2848, 2150 (SCN), 1604, 1506, 1381, 1257,
1170, 750 cm−1. HRMS (ESI), m/z: calcd for C25H30N3O5S3Si [M +
NH4]+: 576.1111, found: 576.1103.
N-(1-(4-Ethoxyphenyl)-2-phenyl-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2o). 2o was synthesized
following the general procedure B: white solid (51 mg, 88% yield,
mixture of 6.7:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.94 (d, J = 7.2 Hz, 4H), 7.58 (t, J =
1
MHz, CDCl3) δ 162.7 (C−F, JC−F = 246.7 Hz), 159.6, 139.4, 137.6
3
4
(C−F, JC−F = 7.9 Hz), 136.9, 134.2, 133.3, 132.3 (C−F, JC−F = 2.4
3
Hz), 130.7 (C−F, JC−F = 8.2 Hz), 129.3, 128.9, 126.5, 126.4 (C−F,
4JC−F = 3.0 Hz), 117.4 (C−F, 2JC−F = 22.9 Hz), 117.0 (C−F, 2JC−F
=
1
21.1 Hz), 114.1, 109.1, 63.5, 14.6 ppm. E-isomer: H NMR (400
MHz, CDCl3) δ 7.61−7.57 (overlap with Z, 3H), 7.49−7.42 (overlap
with Z, 6H), 7.33−7.28 (overlap with Z, 1H), 7.25−7.21 (overlap
with Z, 5H), 6.91−6.87 (m, 1H), 6.77 (d, J = 8.8 Hz, 2H), 4.07 (q, J
= 7.2 Hz, 2H), 1.47 (t, J = 7.2 Hz, 3H) ppm. 13C{1H} NMR (100
7.2 Hz, 2H), 7.46−7.41 (m, 6H), 7.32−7.28 (m, 3H), 7.07 (d, J = 8.8
Hz, 2H), 6.39 (d, J = 8.8 Hz, 2H), 3.89 (q, J = 7.2 Hz, 2H), 1.35 (t, J
= 7.2 Hz, 3H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 159.3,
139.5, 135.6, 135.5, 134.1, 133.3, 130.5. 129.9, 129.3, 129.0, 128.8,
1
MHz, CDCl3) δ 162.4 (C−F, JC−F = 246.4 Hz), 160.4, 139.2, 136.2
3
3
(C−F, JC−F = 8.1 Hz), 135.7, 130.5 (C−F, JC−F = 8.4 Hz), 128.8,
128.3, 126.2, 125.9 (C−F, 4JC−F = 2.9 Hz), 117.4, 114.6, 108.7, 63.7,
14.8 ppm. IR (KBr) 3142, 2987, 2922, 2850, 2160 (SCN), 1602,
1508, 1381, 1259, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C29H27FN3O5S3 [M + NH4]+: 612.1091, found: 612.1085.
1
128.2, 126.9, 113.9, 109.5, 63.4, 14.7 ppm. E-isomer: H NMR (400
MHz, CDCl3) δ 7.75−7.73(m, 2H), 7.60−7.55 (overlap with Z, 2H),
7.45−7.41 (overlap with Z, 2H), 7.37 (d, J = 7.6 Hz, 4H), 7.32−7.28
(overlap with Z, 3H), 7.18 (t, J = 7.6 Hz, 4H), 6.76 (d, J = 8.8 Hz,
2H), 4.05 (q, J = 7.2 Hz, 2H), 1.46 (t, J = 7.2 Hz, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 160.2, 139.1, 133.4, 132.9, 130.2, 130.1,
(Z)-N-(1-(4-Ethoxyphenyl)-2-(3-methoxyphenyl)-2-thiocyanato-
vinyl)-N-(phenylsulfonyl)benzenesulfonamide (2s). 2s was synthe-
sized following the general procedure B: white solid (40 mg, 66%
5332
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J. Org. Chem. 2021, 86, 5327−5335

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Note
1
yield), eluent PE/EtOAc (8:1, v/v); H NMR (400 MHz, CDCl3) δ
2H), 6.85 (d, J = 8.8 Hz, 2H), 5.10 (s, 2H) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 160.0, 139.1, 136.5, 134.8, 133.5, 133.0, 132.3 (C−F,
3JC−F = 8.7 Hz), 130.1, 128.8, 128.7, 128.3, 127.5, 126.7, 116.1 (C−F,
2JC−F = 21.8 Hz), 115.0, 70.1 ppm. IR (KBr) 2920, 2842, 2160
7.94 (d, J = 7.2 Hz, 4H), 7.58 (t, J = 7.6 Hz, 2H), 7.43 (t, J = 7.6 Hz,
4H), 7.21 (t, J = 7.6 Hz, 1H), 7.09 (d, J = 8.8 Hz, 2H), 7.03−7.01 (m,
1H), 6.97−6.96 (m, 1H), 6.85−6.82 (m, 1H), 6.40 (d, J = 8.8 Hz,
2H), 3.89 (q, J = 6.8 Hz, 2H), 3.72 (s, 3H), 1.35 (t, J = 6.8 Hz, 3H)
ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 159.8, 159.3, 139.5, 136.7,
135.7, 134.1, 133.9, 133.1, 130.1, 129.3, 128.8, 127.0, 123.0, 116.0,
115.5, 114.0, 109.4, 63.4, 55.4, 14.7 ppm. IR (KBr) 2920, 2848, 2160
(SCN), 1602, 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI), m/z:
calcd for C30H26KN2O6S3 [M + K]+: 645.0585, found: 645.0581.
N-(2-(2-Fluorophenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2t). 2t was synthesized
following the general procedure B: white solid (44 mg, 74% yield,
mixture of 20:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 7.2 Hz, 4H), 7.59 (t, J =
7.6 Hz, 2H), 7.45 (t, J = 7.6 Hz, 4H), 7.41−7.30 (m, 2H), 7.15 (d, J =
9.2 Hz, 2H), 7.14−7.02 (m, 2H), 6.44 (d, J = 9.2 Hz, 2H), 3.89 (q, J
= 7.2 Hz, 2H), 1.35 (t, J = 7.2 Hz, 3H,) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 159.7 (C−F, 1JC−F = 251.5 Hz), 159.7, 139.4, 138.1,
134.2, 132.5, 132.1 (C−F, JC−F = 8.2 Hz), 131.9 (C−F, JC−F = 1.3
Hz), 129.3, 128.9, 128.2, 126.7, 124.8 (C−F, JC−F = 3.2 Hz), 123.5
(SCN), 1600, 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI), m/z:
calcd for C34H25KFN2O5S3 [M + K]+: 695.0541, found: 695.0539.
N-(2-Phenyl-1-(4-((pivaloyloxy)amino)phenyl)-2-thiocyanato-
vinyl)-N-(phenylsulfonyl)benzenesulfonamide (2x). 2x was synthe-
sized following the general procedure B: white solid (48 mg, 74%
yield, mixture of 8:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-
isomer: 1H NMR (400 MHz, CDCl3) δ 7.94 (d, J = 7.2 Hz, 4H), 7.58
(t, J = 7.6 Hz, 2H), 7.45−7.41 (m, 6H), 7.31−7.29 (m, 3H), 7.06 (d,
J = 8.8 Hz, 2H), 6.88 (d, J = 8.8 Hz, 2H), 6.45 (s, 1H), 1.48 (s, 9H)
ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 152.2, 139.4, 139.0, 135.3,
135.2, 135.2, 134.2, 132.6, 130.4, 130.1, 129.3, 129.1, 128.9, 128.3,
117.3, 109.3, 81.1, 28.3 ppm. IR (KBr) 2926, 2852, 2160 (SCN),
1730, 1604, 1508, 1379, 1259, 1168, 750 cm−1. HRMS (ESI), m/z:
calcd for C32H33N4O6S3 [M + NH4]+: 665.1557, found: 665.1556.
N-(1-(4-Methoxyphenyl)-2-thiocyanato-2-(thiophen-2-yl)vinyl)-
N-(phenylsulfonyl)benzenesulfonamide (2y). 2y was synthesized
following the general procedure B: yellow solid (45 mg, 79% yield,
mixture of 8:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 4H), 7.59 (t, J =
3
4
4
2
2
(C−F, JC−F = 13.8 Hz), 116.5 (C−F, JC−F = 21 Hz), 114.0, 108.9,
63.5, 14.6 ppm. IR (KBr) 2920, 2850, 2158 (SCN), 1602, 1508, 1379,
1255, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for C29H27FN3O5S3
[M + NH4]+: 612.1091, found: 612.1085.
7.6 Hz, 2H), 7.52−7.40 (overlap with E, 5H), 7.26−7.21 (m, 3H),
6.97−6.95 (m, 1H), 6.50 (d, J = 8.8 Hz, 2H), 3.72 (s, 3H) ppm.
13C{1H} NMR (100 MHz, CDCl3) δ 160.3, 139.4, 137.6, 135.5,
N-(1-(4-Phenoxyphenyl)-2-phenyl-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2u). 2u was synthesized
following the general procedure B: white solid (42 mg, 67% yield,
mixture of 4:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.98 (d, J = 8.0 Hz, 4H), 7.61 (t, J =
7.6 Hz, 2H), 7.49−7.40 (overlap with E, 7H), 7.36−7.29 (overlap
with E, 5H), 7.11 (d, J = 8.8 Hz, 2H), 6.91 (d, J = 7.6 Hz, 2H), 6.48
(d, J = 8.8 Hz, 2H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 158.0,
155.7, 139.5, 135.7, 135.3, 135.0, 134.2, 133.3, 130.5, 130.2, 129.9,
129.3, 129.1, 128.9, 128.3, 124.3, 119.7, 117.3, 109.4 ppm. E-isomer:
1H NMR (400 MHz, CDCl3) δ 7.76−7.74 (m, 2H), 7.63−7.59
134.1, 133.3, 132.1, 130.4, 129.2, 128.9, 127.7, 127.2, 126.1, 114.8,
109.4, 55.3 ppm. E-isomer: 1H NMR (400 MHz, CDCl3) δ 8.01 (d, J
= 7.6 Hz, 4H), 7.63 (t, J = 7.2 Hz, 2H), 7.52−7.40 (overlap with Z,
6H), 7.05−7.03 (m, 1H),6.93 (d, J = 8.8 Hz, 2H), 6.71−6.70 (m,
1H), 6.52−6.47 (m, 1H), 3.84 (s, 3H) ppm. 13C{1H} NMR (100
MHz, CDCl3) δ 161.5, 139.4, 138.5, 135.3, 134.4, 132.8, 132.1, 129.4,
129.1, 129.0, 128.2, 127.4, 126.8, 113.7, 109.3, 55.4 ppm. IR (KBr)
2920, 2848, 2160 (SCN), 1602, 1379, 1259, 1168, 750 cm−1. HRMS
(ESI), m/z: calcd for C26H20KN2O5S4 [M + K]+: 606.9887, found:
606.9882.
(overlap with Z, 2H), 7.49−7.40 (overlap with Z, 4H), 7.36−7.29
(overlap with Z, 3H), 7.25−7.12 (m, 5H), 7.15 (d, J = 7.2 Hz, 4H),
7.07 (d, J = 8.0 Hz, 2H), 6.85 (d, J = 8.8 Hz, 2H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 159.2, 155.6, 139.1, 135.0, 134.2, 133.5,
133.5, 133.1, 130.3, 130.1, 130.1, 129.2, 129.0, 128.9, 128.6, 124.5,
120.0, 117.7, 108.8 ppm. IR (KBr) 2922, 2850, 2160 (SCN), 1585,
1504, 1484, 1379, 1274, 1168, 750 cm−1. HRMS (ESI), m/z: calcd for
C33H28N3O5S3 [M + NH4]+: 642.1186, found: 642.1180.
N-(1-(4-(Benzyloxy)phenyl)-2-phenyl-2-thiocyanatovinyl)-N-
(phenylsulfonyl)benzenesulfonamide (2v). 2v was synthesized
following the general procedure B: white solid (40 mg, 63% yield,
mixture of 20:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-isomer:
1H NMR (400 MHz, CDCl3) δ 7.92 (d, J = 7.6 Hz, 4H,), 7.53 (t, J =
7.6 Hz, 2H), 7.45−7.30 (m, 14H), 7.07 (d, J = 8.8 Hz, 2H), 6.47 (d, J
= 8.8 Hz, 2H), 4.93 (s, 2H) ppm. 13C{1H} NMR (100 MHz, CDCl3)
δ 159.0, 139.4, 136.5, 135.4, 134.5, 134.1, 133.3, 132.0, 130.5, 130.0,
129.2, 129.1, 128.8, 128.7, 128.2, 127.4, 127.3, 114.4, 109.4, 69.8
ppm. IR (KBr) 2922, 2850, 2156 (SCN), 1597, 1508, 1458, 1377,
1274, 1166, 750 cm−1. HRMS (ESI), m/z: calcd for C34H26KN2O5S3
[M + K]+: 677.0635, found: 677.0626.
N-(2-(4-Acetylphenyl)-1-(4-methoxyphenyl)-2-thiocyanatovin-
yl)-N-(phenylsulfonyl)benzenesulfonamide (2za). 2za was synthe-
sized following the general procedure B: yellow solid (48 mg, 79%
yield, mixture of 4:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-
isomer: 1H NMR (400 MHz, CDCl3) δ 7.96 (d, J = 7.6 Hz, 4H), 7.92
(d, J = 8.4 Hz, 2H), 7.62 (t, J = 7.6 Hz, 2H), 7.58 (d, J = 7.6 Hz, 2H),
7.47 (t, J = 8.0 Hz, 4H), 7.10 (d, J = 9.2 Hz, 2H), 6.44 (d, J = 9.2 Hz,
2H), 3.71 (s, 3H), 2.60 (s, 3H) ppm. 13C{1H} NMR (100 MHz,
CDCl3) δ 197.2, 160.3, 140.1, 139.3, 137.6, 137.3, 134.3, 133.5, 130.8,
130.4, 129.2, 128.9, 128.3, 126.6, 113.7, 109.1, 55.3, 26.7 ppm. E-
1
isomer: H NMR (400 MHz, CDCl3) δ 7.86−7.79 (m, 4H), 7.63−
7.60 (overlap with Z, 2H), 7.49−7.43 (overlap with Z, 6H), 7.19 (t, J
= 7.6 Hz, 4H), 6.82 (d, J = 8.8 Hz, 2H), 3.87 (s, 3H), 2.60 (s, 3H)
ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 197.0, 161.1, 139.1, 138.5,
137.8, 136.3, 133.1, 132.6, 131.9, 128.9, 128.7, 126.3, 114.2, 108.7,
55.5, 26.7 ppm. IR (KBr) 2921, 2848, 2158 (SCN), 1685, 1603, 1509,
1379, 1260, 1169, 750 cm−1. HRMS (ESI), m/z: calcd for
C30H25N2O6S3 [M + H]+: 605.0869, found: 605.0863.
N-((1E,3E)-1-(4-Methoxyphenyl)-4-phenyl-2-thiocyanatobuta-
1,3-dien-1-yl)-N-(phenylsulfonyl)benzenesulfonamide (2zb). 2zb
was synthesized following the general procedure B: yellow solid (43
mg, 73% yield, mixture of 1:12 Z:E isomers), eluent PE/EtOAc (8:1,
N-(1-(4-(Benzyloxy)phenyl)-2-(4-fluorophenyl)-2-thiocyanato-
vinyl)-N-(phenylsulfonyl)benzenesulfonamide (2w). 2w was synthe-
sized following the general procedure B: white solid (54 mg, 84%
yield, mixture of 2.6:1 Z:E isomers), eluent PE/EtOAc (8:1, v/v); Z-
isomer: 1H NMR (400 MHz, CDCl3) δ 7.91 (d, J = 7.6 Hz, 4H), 7.53
(t, J = 7.6 Hz, 2H), 7.47−7.35 (overlap with E, 11H), 7.05 (d, J = 8.4
Hz, 2H), 7.01 (t, J = 8.4 Hz, 2H), 6.50 (d, J = 9.2 Hz, 2H), 4.95 (s,
1
v/v); E-isomer: H NMR (400 MHz, CDCl3) δ 7.73 (d, J = 7.6 Hz,
4H), 7.46 (d, J = 9.2 Hz, 2H), 7.29 (t, J = 7.6 Hz, 2H), 7.20−7.16 (m,
7H), 7.04 (d, J = 15.6 Hz, 1H), 6.99 (d, J = 6.8 Hz, 2H), 6.73 (d, J =
8.8 Hz, 2H), 6.63 (d, J = 15.6 Hz, 1H), 3.77 (s, 3H) ppm. 13C{1H}
NMR (100 MHz, CDCl3) δ 161.1, 139.7, 139.1, 137.9, 135.3, 133.9,
133.2, 129.4, 129.2, 128.8, 128.7, 128.5, 127.7, 127.3, 123.4, 113.9,
109.3, 55.5 ppm. IR (KBr) 2920, 2842, 2157 (SCN), 1653, 1602,
1506, 1379, 1258, 1170, 752 cm−1. HRMS (ESI), m/z: calcd for
C30H24N2NaO5S3 [M + Na]+: 611.0740, found: 611.0746.
2H) ppm. 13C{1H} NMR (100 MHz, CDCl3) δ 163.3 (C−F, 1JC−F
=
250.6 Hz), 159.1, 139.4, 136.4, 135.8, 134.2, 134.0, 133.3, 132.7,
3
4
132.6 (C−F, JC−F = 8.6 Hz), 131.4 (C−F, JC−F = 3.4 Hz), 129.2,
128.8, 128.2 (C−F, 4JC−F = 2.3 Hz), 127.4, 127.1, 116.4 (C−F, 2JC−F
1
= 22.0 Hz), 114.5, 109.3, 69.8 ppm. E-isomer: H NMR (400 MHz,
(Z)-1-(4-Ethoxyphenyl)-2-phenyl-2-thiocyanatoethen-1-amine
(3o). 3o was synthesized following procedure C: white solid (420 mg,
81% yield), eluent PE/EtOAc (4:1, v/v); 1H NMR (700 MHz,
CDCl3) δ 7.72−7.68 (m, 2H), 7.57 (d, J = 8.8 Hz, 2H), 7.47−7.35
(overlap with Z, 11H), 7.18 (t, J = 8.0 Hz, 4H), 6.90 (t, J = 7.2 Hz,
5333
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J. Org. Chem. 2021, 86, 5327−5335

The Journal of Organic Chemistry
pubs.acs.org/joc
Note
(CD3)2CO) δ 7.39 (d, J = 9.1 Hz, 2H), 7.32−7.25 (m, 5H), 6.80 (d, J
= 9.1 Hz, 2H), 6.43 (s, 2H), 4.04 (q, J = 7.0 Hz, 2H), 1.36 (t, J = 7.0
Hz, 3H) ppm. 13C{1H} NMR (175 MHz, (CD3)2CO)) δ 168.8,
158.4, 145.4, 133.6, 130.0, 129.3, 128.6, 128.2, 126.9, 119.0, 113.7,
63.0, 14.2 ppm. IR (KBr) 3433, 3269, 2158 (SCN), 1606, 1531, 1246,
1178, 758 cm−1. HRMS (ESI), m/z: calcd for C17H17N2OS [M +
H]+: 297.1056, found: 297.1047.
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ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.joc.0c02780.
■
sı
Characterization data, copies of NMR spectra (PDF)
AUTHOR INFORMATION
Corresponding Authors
■
Hongquan Yin − School of Chemistry & Chemical
Engineering, Beijing Institute of Technology (Liangxiang
Campus), Beijing 102488, China; State Key Laboratory of
Medicinal Chemical Biology, NanKai University, Tianjin
300071, China; Email: hqyin77@bit.edu.cn
Fu-Xue Chen − School of Chemistry & Chemical Engineering,
Beijing Institute of Technology (Liangxiang Campus), Beijing
102488, China; orcid.org/0000-0002-9091-2147;
Email: fuxue.chen@bit.edu.cn
Authors
Haopeng Wu − School of Chemistry & Chemical Engineering,
Beijing Institute of Technology (Liangxiang Campus), Beijing
102488, China; orcid.org/0000-0003-3302-4597
Chukai Shao − School of Chemistry & Chemical Engineering,
Beijing Institute of Technology (Liangxiang Campus), Beijing
102488, China
Di Wu − School of Chemistry & Chemical Engineering, Beijing
Institute of Technology (Liangxiang Campus), Beijing
102488, China
Liang Jiang − School of Chemistry & Chemical Engineering,
Beijing Institute of Technology (Liangxiang Campus), Beijing
102488, China
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.joc.0c02780
Notes
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Masson, G. Enamide derivatives: versatile building blocks for highly
functionalized α,β-substituted amines. Synlett 2014, 25, 2842−2867.
(e) Courant, T.; Dagousset, G.; Masson, G. Enamide Derivatives:
Versatile building blocks for total synthesis. Synthesis 2015, 47, 1799−
1826. (f) Pan, X.; Cai, Q.; Ma, D. CuI/N, N-dimethylglycine-
catalyzed coupling of vinyl halides with amides or carbamates. Org.
Lett. 2004, 6, 1809−1812. (g) Lee, J. M.; Ahn, D.-S.; Jung, D. Y.; Lee,
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The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
The financial support from NSFC (21971013) and the State
Key Laboratory of Medicinal Chemical Biology (2018060) is
acknowledged.
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