Iodine-catalyzed addition of methyl thioglycolate to chalcones

Article abstract of DOI:10.1080/10426507.2011.643435

A series of novel -mercapto carbonyl compounds (3a-z), methyl 2-(3-oxo-1,3-diarylpropylthio)acetate, were synthesized and characterized via iodine-catalyzed addition of methyl thioglycolate to chalcones (1a-z). Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Full text of DOI:10.1080/10426507.2011.643435

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Iodine-Catalyzed Addition of Methyl
Thioglycolate to Chalcones
M. Burcu Gürdere a , Hayreddin Gezegen a , Yakup Budak a & Mustafa
Ceylan a
a Department of Chemistry, Faculty of Arts and Sciences ,
Gaziosmanpasa University , Tokat , Turkey
Accepted author version posted online: 04 Jan 2012.Published
online: 07 Jun 2012.
To cite this article: M. Burcu Gürdere , Hayreddin Gezegen , Yakup Budak & Mustafa Ceylan (2012)
Iodine-Catalyzed Addition of Methyl Thioglycolate to Chalcones, Phosphorus, Sulfur, and Silicon and
the Related Elements, 187:8, 889-898, DOI: 10.1080/10426507.2011.643435
To link to this article: http://dx.doi.org/10.1080/10426507.2011.643435
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Phosphorus, Sulfur, and Silicon, 187:889–898, 2012
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426507.2011.643435
IODINE-CATALYZED ADDITION OF METHYL
THIOGLYCOLATE TO CHALCONES
M. Burcu Gu¨rdere, Hayreddin Gezegen, Yakup Budak,
and Mustafa Ceylan
Department of Chemistry, Faculty of Arts and Sciences, Gaziosmanpasa
University, Tokat, Turkey
GRAPHICAL ABSTRACT
Abstract A series of novel β-mercapto carbonyl compounds (3a–z), methyl 2-(3-oxo-1,3-
diarylpropylthio)acetate, were synthesized and characterized via iodine-catalyzed addition of
methyl thioglycolate to chalcones (1a–z).
Supplemental materials are available for this article. Go to the publisher’s online edition of
Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.
Keywords Iodine; chalcones; Michael addition; methyl thioglycolate
INTRODUCTION
The Michael addition is a useful reaction in organic chemistry for the construction
of carbon–carbon and carbon–hetero atom bonds.1–6 The Michael addition provides a
possibility to synthesize many synthetically and biologically important compounds such as
1,5-diketones,7 quinolines,8 β-amino carbonyls,9 β-mercapto carbonyl derivatives,10,11 and
chiral auxiliaries.12
Recently, molecular iodine-catalyzed addition of thiols to α,β-unsaturated carbonyl
compounds has attracted much attention and there are various studies in the literature on
this issue.10,13,14 The catalytic activity of iodine in the Michael addition of indole to enones
and several organic transformations has also been reported.15 In addition, Chu et al.16
and Gao et al.17 have reported the iodine-catalyzed addition of mercaptans (such as PhSH
Received 15 July 2011; accepted 19 November 2011.
Address correspondence to Mustafa Ceylan, Department of Chemistry, Faculty of Arts and Sciences, Gazios-
manpasa University, 60250, Tokat, Turkey. E-mail: mustafac.ceylan@gop.edu.tr
889

¨
M. BURCU GURDERE ET AL.
890
and RSH) to α,β-unsaturated ketones and α,β-unsaturated acids. As can be seen in these
studies, molecular iodine is a powerful catalyst for 1,4-addition to afford products in good
to excellent yields.
Although the conjugate addition of thiols to α,β-unsaturated carbonyl compounds
is a well-known procedure, there is a rare example of addition of methyl thioglycolate18
to chalcones. For this reason, in this paper, novel β-mercapto carbonyl compounds (3a–z)
were synthesized and characterized via iodine-catalyzed addition of methyl thioglycolate
to chalcones (1a–z).
RESULTS AND DISCUSSION
Firstly, the chalcone derivatives 1a–z were synthesized employing the general method
reported in the literature.19,20 Then, the iodine-catalyzed addition of methyl thioglycolate
to chalcones (3a–z) was investigated. The best results were obtained using 10% mol iodine
solution in CH2Cl2 in some experiments performed to determine the amount of iodine. In
1
these experiments, the reactions yields were checked from the H NMR spectra, and the
results are given in Table 1.
Scheme 1 Schematic representation of the synthesized compounds.
Treatment of chalcone derivatives (1a–z) with methyl thioglycolate (2) and a so-
lution of 10% mol iodine in CH2Cl2 at room temperature yielded methyl 2-(3-oxo-1,3-
diarylpropylthio)acetate derivatives (3a–z). Crude products were purified on a silica gel
column eluting with CHCl3/n-hexane (3:7). The isolated yield of the obtained derivatives
(3a–z) was in the range of 68%–97%. The addition reactions were completed in the range
of 0.5 h–3.0 h. While the additions to p-substituted chalcones were completed for 0.5 h,
additions to –OH-substituted chalcones (1b, 1h, and 1v) were completed for 3 h. The results
and physical properties are summarized in Table 2.
The structures of 3a–z were elucidated by means of spectroscopic studies (1H and 13
C
NMR, IR, and elemental analyses). The IR spectra of these compounds revealed two sharp
strong absorption bands between the range of 1735–1708 cm−1 and 1698–1639 cm−1
.
Table 1 Reaction of 1a with 2 utilizing different quantities of iodine
Exp.
I2 (mol%)
Time (h)
3a (%)
1a (%)
1
2
3
4
0
1
5
8
1
1
1
0
99
84
17
0
16
83
99
10
The yields were determined by 1H-NMR.

IODINE-CATALYZED ADDITION OF METHYL THIOGLYCOLATE TO CHALCONES 891
Table 2 Iodine-catalyzed synthesized compounds (3a–z)
Entry
Ar
Arꢁ
Product
Time (h)
Yield (%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
o-Cl-C6H4
o-OH-C6H4
m-OCH3-C6H4
m-Br-C6H4
p-CH3-C6H4
Ph
Ph
Ph
Ph
Ph
p-OCH3-C6H4
p-Cl-C6H4
o-OCH3-C6H4
m-OCH3-C6H4
p-OCH3-C6H4
o-Cl-C6H4
m-Cl-C6H4
p-Cl-C6H4
o-Br-C6H4
m-Br-C6H4
p-Br-C6H4
o-OH-C6H4
2-furyl
Ph
Ph
Ph
Ph
Ph
3a
3b
3c
3d
3e
3f
3g
3h
3i
3j
3k
3l
3m
3n
3o
3p
3q
3r
1.0
3.0
1.0
1.5
0.5
2.0
1.5
3.0
0.5
0.5
0.5
1.0
1.0
1.0
0.5
1.0
2.0
0.5
1.0
1.0
0.5
3.0
1.0
0.5
2.0
1.0
80
74
75
77
81
70
62
68
92
77
86
73
76
83
97
84
88
94
88
73
94
89
68
84
68
73
o-OCH3-C6H4
m-Cl-C6H4
m-OH-C6H4
p-Br-C6H4
p-CH3-C6H4
p-OCH3-C6H4
p-Cl-C6H4
2-furyl
2-furyl
2-furyl
2-furyl
2-furyl
2-furyl
2-furyl
2-furyl
2-furyl
3s
3t
3u
3v
3w
3x
3y
3z
2-furyl
o-OCH3-C6H4
p-Br-C6H4
2-thiophenyl
2-thiophenyl
2-furyl
m-Br-C6H4
p-Br-C6H4
These absorption bands confirm the presence of the ketone and ester carbonyl groups,
respectively. In addition, the 13C-NMR spectrum of 3a–z showed two carbonyl signals at
205.9–194.5 ppm and 171.2–170.4 ppm. In the 1H-NMR spectra, these compounds showed
the AB system due to protons attached to the ketone carbon atom (ArCOCH2) ranging
from 3.10–2.90 ppm. All these data and elemental analyses results confirmed the proposed
structures.
The mechanism of the reaction of methyl thioglycolate with chalcones in the presence
of iodine can be explained as shown Scheme 2. In agreement with this mechanism, iodine
having mild Lewis acidity, activates the carbonyl group of the chalcone and facilitates
conjugate addition of methyl thioglycolate.14
Scheme 2 Proposed reaction mechanism.

¨
892
M. BURCU GURDERE ET AL.
Consequently, a series of novel methyl 2-(3-oxo-1,3-diarylpropylthio)acetate deriva-
tives (3a–z) were prepared by the addition of methyl thioglycolate to chalcones (1a–z) in
the presence of catalytic amount of iodine (10% mol) in CH2Cl2. The present procedure for
the synthesis of methyl 2-(3-oxo-1,3-diarylpropylthio)acetate derivatives has the advantage
of mild reaction conditions, inexpensive catalyst with high yields of products, and simple
experimental work-up procedure.
EXPERIMENTAL
General
Melting points were measured on Electrothermal 9100 apparatus. IR spectrums (KCl
1
disc) were recorded on a Jasco FT/IR-430 spectrometer. H and 13C NMR spectra were
recorded on a Bruker Avance DPX-400 instrument. As internal standards served TMS (δ =
1
0.00) for H NMR and CDCl3 (δ = 77.0) for 13C NMR spectroscopy, J values are given
1
in hertz (Hz). The multiplicities of signals in the H NMR spectra are abbreviated by s
(singlet), d (doublet), t (triplet), q (quartet), m (multiplet), br (broad), and combinations
thereof. Elemental analyses were obtained from a LECO CHNS 932 Elemental Analyzer.
Column chromatography in all cases was performed on silica gel (60-230 mesh, Merck).
General Procedure for the Synthesis of 3a–z
Iodine (10% mole) solution in dichloromethane (1 mL) was added to a solution of
methyl thioglycolate (1.2 mmol) and chalcone (1 mmol) in CH2Cl2 (5 mL) and the mixture
was stirred for 0.5 h–3 h at room temperature. After the completion of the reaction, the
iodine was removed with diluted Na2SO3 (0.06 M) and extracted with CH2Cl2. The organic
layer was dried over Na2SO4 and the solvent was removed under reduced pressure. The
crude product was purified on a silica gel column eluting with CHCl3/n-hexane (3:7) and/or
crystallized in CHCl3/n-hexane (3:7). Selected NMR spectra for 3k and 3x (Figures S1–S4)
are presented in the Supplemental Materials.
Spectral Data
Methyl 2-(3-(2-chlorophenyl)-3-oxo-1-phenylpropylthio) acetate (3a). Viscous
1
oil, yield 80%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.31–7.27 (m, 3H), 7.26–7.14
(m, 3H), 7.12–7.07 (m, 3H), 4.62 (t, J = 7.1 Hz, 1H), 3.58 (s, 3H), 3.52 (br d, J = 7.3
Hz, 2H), 3.05 (d, J = 15.0 Hz, 1H, A part of AB system), 2.96 (d, J = 15.0 Hz, 1H, B
part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 199.5, 170.5, 140.2, 138.9,
132.0, 130.7, 130.4, 129.2, 128.6 (2C), 128.1 (2C), 127.7, 127.0, 52.32, 48.8, 45.0, 32.7.
IR (KCl): 3062, 3029, 2950, 2904, 2840, 1735, 1698, 1589, 1454, 1434, 1278, 1159, 1132,
1070, 1008, 985, 757, 700 cm−1. Anal. Cald. for C18H17ClO3S: C, 61.97; H, 4.91; S, 9.19.
Found: C, 60.68; H, 4.98; S, 9.09.
Methyl 2-(3-(2-hydroxyphenyl)-3-oxo-1-phenylpropylthio) acetate (3b). Viscous
oil, yield 74%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 12.05 (s, 1H, –OH), 7.72 (d, J =
15.0 Hz, 1H), 7.44–7.40 (m, 3H), 7.32 (t, J = 7.4 Hz, 2H), 7.24 (t, J = 7.2 Hz, 1H), 6.92
(d, J = 8.4 Hz, 1H), 6.87 (t, J = 7.6 Hz, 1H), 4.74 (t, J = 7.0 Hz, 1H), 3.65 (s, 3H), 3.60
(d, J = 7.2 Hz, 2H), 3.10 (d, J = 15.2 Hz, 1H, A part of AB system), 3.00 (d, J = 15.2 Hz,
1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 202.3, 170.6, 162.4,

IODINE-CATALYZED ADDITION OF METHYL THIOGLYCOLATE TO CHALCONES 893
140.4, 136.6, 129.8, 128.7 (2C), 128.1 (2C), 127.8, 119.2, 119.1, 118.6, 52.4, 44.4, 44.2,
32.8. IR (KCl): 3058, 3029, 2950, 2906, 2840, 1735, 1639, 1583, 1488, 1446, 1340, 1276,
1207, 1157, 1004, 985, 755, 700 cm−1. Anal. Cald. for C18H18O4S: C, 65.43; H, 5.19; S,
9.70. Found: C, 65.68; H, 5.45; S, 9.59.
Methyl 2-(3-(3-methoxyphenyl)-3-oxo-1-phenylpropylthio) acetate (3c). Viscous
oil, yield 75%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.49 (d, J = 7.6 Hz, 1H), 7.44–7.41
(m, 3H), 7.37–7.30 (m, 3H), 7.28–7.21 (m, 1H), 7.09 (dd, J = 12.4 Hz, J = 2.0 Hz, 1H),
4.74 (t, J = 7.0 Hz, 1H), 3.82 (s, 3H), 3.66 (s, 3H), 3.58 (br d, J = 7.6 Hz, 2H), 3.11 (d,
J = 15.0 Hz, 1H, A part of AB system), 3.01 (d, J = 15.0 Hz, 1H, B part of AB system).
13C-NMR (100 MHz, CDCl3, ppm): δ = 196,2, 170.7, 159.8, 140.8, 137.9, 129.6, 128.6
(2C), 128.1 (2C), 127.6, 120.7, 119.9, 112.2, 55.4, 52.4, 44.8, 44.7, 32.9. IR (KCl): 3089,
3031, 2906, 2834, 1708, 1683, 1596, 1583, 1488, 1454, 1428, 1288, 1261, 1162, 1039, 993,
871, 769, 701, 684 cm−1. Anal. Cald. for C19H20O4S: C, 66.26; H, 5.85; S, 9.31. Found:
C, 66.28; H, 5.45; S, 9.29.
Methyl 2-(3-(3-bromophenyl)-3-oxo-1-phenylpropylthio) acetate (3d). Viscous
oil, yield 77%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.92 (s, 1H), 7.20 (d, J = 8.0 Hz,
1H), 7.55 (d, J = 8.0 Hz, 1H), 7.33 (d, J = 7.6 Hz, 2H), 7.24–7.12 (m, 4H), 4.64 (t, J =
7.0 Hz, 1H), 3.64 (s, 3H), 3.47 (d, J = 7.2 Hz, 2H), 3.48 (d, J = 15.0 Hz, 1H, A part of AB
system), 2.92 (d, J = 15.0 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3,
ppm): δ = 195.0, 170.6, 140.5, 138.2, 136.1, 131.0, 130.3, 128.6 (2C), 128.0 (2C), 127.6,
126.6, 122.9, 52.4, 44.7, 41.1, 32.8. IR (KCl): 3062, 3027, 3002, 2950, 2842, 1731, 1691,
1589, 1565, 1454, 1434, 1419, 1332, 1280, 1197, 1130, 1006, 894, 773, 700, 545 cm−1
.
Anal. Cald. for C18H17BrO3S: C, 54.97; H, 4.36; S, 8.15. Found: C, 54.68; H, 4.45; S, 8.09.
Methyl 2-(3-oxo-3-phenyl-1-p-tolylpropylthio) acetate (3e). Yellow crystal, yield
81%, M.P.: 64 ◦C–66 ◦C. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.90 (d, J = 7.6 Hz, 2H),
7.56–7.48 (m, 1H), 7.42 (t, J = 7.6 Hz, 2H), 7.32 (d, J = 8.0 Hz, 2H, AAꢁ part of AAꢁBBꢁ
system), 7.12 (d, J = 8.0 Hz, 2H, BBꢁ part of AAꢁBBꢁ system), 4.73 (t, J = 7.0 Hz, 1H),
3.65 (s, 3H), 3.57 (d, J = 6.0 Hz, 2H), 3.09 (d, J = 15.2 Hz, 1H, A part of AB system),
3.01 (d, J = 15.2 Hz, 1H, B part of AB system), 2.30 (s, 3H). 13C-NMR (100 MHz, CDCl3,
ppm): δ = 196.4, 170.7, 137.7, 137.2, 136.6, 133.3, 129.3 (2C), 128.6 (2C), 128.1 (2C),
128.0 (2C), 52.3, 44.7, 44.4, 32.8, 21.1. IR (KCl): 3056, 3025, 2950, 2896, 1735, 1685,
1596, 1508, 1448, 1434, 1330, 1280, 1224, 1157, 1132, 1002, 981, 813, 763, 690 cm−1
Anal. Cald. for C19H20O3S: C, 69.48; H, 6.14; S, 9.76. Found: C, 69.18; H, 6.15; S, 9.69.
.
Methyl 2-(1-(2-methoxyphenyl)-3-oxo-3-phenylpropylthio) acetate (3f). Viscous
1
oil, yield 70%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.94 (br d, 2H), 7.58–7.52 (m,
1H), 7.46–7.40 (m, 3H), 7.27–7.20 (m, 1H), 6.95–6.86 (m, 2H), 5.06 (t, J = 6.7 Hz, 1H),
3.84 (s, 3H), 3.66–3.59 (m, 5H), 3.26–3.16 (m, 2H). 13C-NMR (100 MHz, CDCl3, ppm):
δ = 197.0, 170.8, 157.0, 140.4, 136.8, 133.1, 129.1, 128.6 (2C), 128.5, 128.1 (2C), 120.7,
111.0, 55.6, 52.3, 44.2, 39.6, 33.7. IR (KCl): 3064, 3029, 3002, 2950, 2836, 1735, 1685,
1596, 1492, 1448, 1436, 1286, 1247, 1159, 1025, 1002, 983, 755, 690 cm−1. Anal. Cald.
for C19H20O4S: C, 66.26; H, 5.85; S, 9.31. Found: C, 66.08; H, 5.65; S, 9.12.
Methyl 2-(1-(3-chlorophenyl)-3-oxo-3-phenylpropylthio) acetate (3g). Viscous
1
oil, yield 62%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.88 (br d, J = 7.2 Hz, 2H),
7.55–7.48 (m, 2H), 7.41 (t, J = 7.8 Hz, 3H), 7.33–7.29 (m, 1H), 7.25–7.19 (m, 1H), 4.71 (t,
J = 7.0 Hz, 1H), 3.64 (s, 3H), 3.56 (t, J = 6.4 Hz, 2H), 3.11 (d, J = 14.8 Hz, 1H, A part of
AB system), 3.00 (d, J = 14.8 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3,
ppm): δ = 195.8, 170.4, 143.2, 136.4, 134.4, 133.5, 129.8, 128.7 (2C), 128.1, 128.0 (2C),
127.8, 126.6, 52.4, 44.5, 44.1, 32.9. IR (KCl): 3062, 2950, 2902, 2840, 1735, 1685, 1594,

¨
M. BURCU GURDERE ET AL.
894
1575, 1448, 1434, 1353, 1280, 1224, 1159, 1000, 981, 786, 755, 690 cm−1. Anal. Cald. for
C18H17ClO3S: C, 61.97; H, 4.91; S, 9.19. Found: C, 61.68; H, 4.65; S, 9.12.
Methyl 2-(1-(3-hydroxyphenyl)-3-oxo-3-phenylpropylthio) acetate (3h). Viscous
oil, yield 68%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.89 (d, J = 7.6 Hz, 2H), 7.54 (t,
J = 7.4 Hz, 1H), 7.42 (t, J = 7.6 Hz, 2H), 7.15 (t, J = 7.8 Hz, 1H), 6.95 (t, J = 7.4 Hz,
2H), 6.74 (dd, J = 8.0 Hz, J = 1.8 Hz, 1H), 5.75 (br s, 1H, –OH), 4.68 (t, J = 7.2 Hz, 1H),
3.63 (s, 3H), 3.56 (dd, J = 6.8 Hz, J = 3.0 Hz, 2H), 3.12 (d, J = 15.0 Hz, 1H, A part of AB
system), 3.06 (d, J = 15.0 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3,
ppm): δ = 197.1, 171.2, 156.3, 142.3, 136.4, 133.5, 129.8, 128.7 (2C), 128.2 (2C), 120.0,
115.1, 114.9, 52.6, 44.7, 44.6, 33.0. IR (KCl): 3401, 3064, 2952, 2840, 1733, 1685, 1596,
1450, 1436, 1280, 1224, 1157, 1000, 896, 763, 692 cm−1. Anal. Cald. for C18H18O4S: C,
65.43; H, 5.49; S, 9.70. Found: C, 65.28; H, 5.45; S, 9.49.
Methyl 2-(1-(4-bromophenyl)-3-oxo-3-phenylpropylthio) acetate (3i). Viscous
oil, yield 92%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.88 (d, J = 8.4 Hz, 2H), 7.54 (t,
J = 7.4 Hz, 1H), 7.42 (t, J = 7.4 Hz, 4H), 7.30 (d, J = 8.4 Hz, 2H), 4.69 (t, J = 7.0 Hz,
1H), 3.65 (s, 3H), 3.54 (d, J = 7.2 Hz, 2H), 3.09 (d, J = 15.2 Hz, 1H, A part of AB system),
2.97 (d, J = 15.2 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm):
δ = 196.0, 170.5, 140.0, 136.4, 133.5, 131.7 (2C), 129.9 (2C), 128.7 (2C), 128.0 (2C),
121.3, 52.4, 44.5, 44.0, 32.8. IR (KCl): 3060, 3025, 3002, 2950, 2904, 2840, 1735, 1685,
1596, 1579, 1486, 1448, 1434, 1405, 1353, 1280, 1224, 1157, 1132, 1072, 1010, 983, 754,
690 cm−1. Anal. Cald. for C18H17BrO3S: C, 54.97; H, 4.36; S, 8.15. Found: C, 54.68; H,
4.45; S, 8.09.
Methyl 2-(3-oxo-1-phenyl-3-p-tolylpropylthio) acetate (3j). Viscous oil, yield
1
77%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.81 (d, J = 8.0 Hz, 2H), 7.43 (d, J =
7.6 Hz, 2H), 7.31 (t, J = 7.6 Hz, 2H), 7.22 (br d, J = 8.0 Hz, 3H), 4.74 (t, J = 7.0 Hz, 1H),
3.64 (s, 3H), 3.56 (d, J = 7.2 Hz, 2H), 3.10 (d, J = 15.2 Hz, 1H, A part of AB system),
3.01 (d, J = 15.2 Hz, 1H, B part of AB system), 2.38 (s, 3H). 13C-NMR (100 MHz, CDCl3,
ppm): δ = 195.9, 170.6, 144.1, 140.9, 134.1, 129.3 (2C), 128.6 (2C), 128.2 (2C), 128.1
(2C), 127.6, 52.6, 44.8, 44.6, 32.9, 21.7. IR (KCl): 3029, 2952, 2886, 2830, 1739, 1677,
1604, 1558, 1540, 1450, 1419, 1340, 1295, 1182, 1147, 997, 813, 703 cm−1. Anal. Cald.
for C19H20O3S: C, 69.48; H, 6.14; S, 9.76. Found: C, 69.68; H, 6.05; S, 9.52.
Methyl 2-(1,3-bis(◦4-methoxyphenyl)-3-oxopropylthio) acetate (3k). Yellow crys-
◦
1
tal, yield 86%, M.P.: 63 C–65 C. H-NMR (400 MHz, CDCl3, ppm): δ = 7.87 (d, J =
8.8 Hz, 2H, AAꢁ part of AAꢁXXꢁ system), 7.32 (d, J = 8.8 Hz, 2H, AAꢁ part of AAꢁBBꢁ
system), 6.87 (d, J = 8.8 Hz, 2H, BBꢁ part of AAꢁBBꢁ system), 6.81 (d, J = 8.8 Hz, 2H, XXꢁ
part of AAꢁXXꢁ system), 4.69 (t, J = 7.0 Hz, 1H), 3.80 (s, 3H), 3.73 (s, 3H), 3.63 (s, 3H),
3.54–3.43 (m, 2H), 3.07 (d, J = 15.2 Hz, 1H, A part of AB system), 2.98 (d, J = 15.2 Hz,
1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 195.0, 170.8, 163.6,
158.8, 132.7, 130.4 (2C), 129.7, 129.2 (2C), 113.9 (2C), 113.8 (2C), 55.5, 55.2, 52.4, 44.4
(2C), 32.8. IR (KCl): 3012, 2952, 2906, 2884, 2836, 1731, 1670, 1602, 1575, 1508, 1457,
1419, 1336, 1292, 1255, 1230, 1172, 1128, 1024, 981, 817, 792, 539 cm−1. Anal. Cald. for
C20H22O5S: C, 64.15; H, 5.92; S, 8.56. Found: C, 64.08; H, 5.88; S, 8.41.
Methyl 2-(1,3-bis(4-chlorophenyl)-3-oxopropylthio) acetate (3l). Viscous oil,
yield 73%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.73 (br d, J = 8.4 Hz, 2H), 7.29 (br d,
J = 8.4 Hz, 4H), 7.17 (d, J = 8.4 Hz, 2H), 4.62 (t, J = 6.8 Hz, 1H), 3.55 (s, 3H), 3.46 (d,
J = 6.4 Hz, 2H), 3.02 (d, J = 14.8 Hz, 1H, A part of AB system), 2.90 (d, J = 14.8 Hz,
1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 194.8, 170.4, 139.7,
139.3, 134.7, 133.1, 129.5 (2C), 129.4 (2C), 128.9 (2C), 128.8 (2C), 52.4, 44.5, 43.8,

IODINE-CATALYZED ADDITION OF METHYL THIOGLYCOLATE TO CHALCONES 895
32.7. IR (KCl): 3104, 2998, 2952, 2913, 1727, 1683, 1587, 1488, 1432, 1405, 1303, 1280,
1222, 1170, 1155, 1093, 1012, 981, 829, 752, 509 cm−1. Anal. Cald. for C18H16Cl2O3S:
C, 56.40; H, 4.21; S, 8.37. Found: C, 56.23; H, 4.15; S, 8.39.
Methyl 2-(1-(furan-2-yl)-3-(2-methoxyphenyl)-3-oxopropylthio) acetate (3m).
1
Viscous oil, yield 76%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.64 (d, J = 7.3 Hz,
1H), 7.44 (t, J = 7.8 Hz, 1H), 7.32 (s, 1H), 6.97–6.93 (m, 2H), 6.26 (s, 1H), 6.21 (d, J =
3.1 Hz, 1H), 4.75 (t, J = 7.1 Hz, 1H), 3.89 (s, 3H), 3.65 (s, 3H), 3.71 (dd, J = 17.6, 8.0 Hz,
1H), 3.54 (dd, J = 17.6, 6.4 Hz, 1H), 3.16 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ =
197.8, 170.6, 158.7, 152.9, 142.2, 133.9, 130.6, 127.3, 120.7, 111.5, 110.1, 107.7, 55.2,
52.6, 47.0, 41.1, 32.7. IR (KCl): 1742, 1598, 1540, 1234, 1029, 1018, 748, 721 cm−1. Anal.
Cald. for C17H18O5S: C, 61.06; H, 5.43; S, 9.59. Found: C, 61.00; H, 5.39; S, 9.49.
Methyl 2-(1-(furan-2-yl)-3-(3-methoxyphenyl)-3-oxopropylthio) acetate (3n).
1
Viscous oil, yield 83%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.55–7.52 (m, 2H, H10,
H14), 7.48–7.46 (m, 1H), 7.37–7.35 (m, 1H), 7.13–7.10 (m, 1H), 6.29–6.27 (m, 2H), 4.81
(dd, J = 7.8, 6.0 Hz, 1H), 3.84 (s, 3H), 3.72 (s, 3H), 3.73 (dd, J = 17.4, 7.8 Hz, 1H),
3.55 (J = 17.4, 6.3 Hz, 1H), 3.20 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 195.8,
170.6, 159.8, 152.4, 142.3, 137.8, 129.5, 120.7, 120.0, 112.2, 110.2, 108.0, 55.4, 52.5,
42.0, 37.7, 32,8. IR (KCl): 1754, 1640, 1551, 1223, 1017, 1001, 786, 729 cm−1. Anal.
Cald. for C17H18O5S: C, 61.06; H, 5.43; S, 9.59. Found: C, 59.87; H, 5.38; S, 9.55.
Methyl 2-(1-(furan-2-yl)-3-(4-methoxyphenyl)-3-oxopropylthio) acetate (3o).
Viscous oil, yield 97%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.93 (d, J = 8.8 Hz 2H,
AAꢁ), 7.34 (s, 1H), 6.93 (d, J = 8.8 Hz 2H, XXꢁ), 6.28–6.26 (m, 2H), 4.81 (t, J = 7.4
Hz, 1H), 3.87 (s, 3H), 3.69 (s, 3H), 3.68 (dd, J = 17.2, 7.9 Hz, 1H), 3.50 (dd, J = 17.2,
6.3 Hz, 1H), 3.20 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 194.5, 170.7, 163.7,
152.6, 142.3, 130.4, 129.5 (2C), 113.8 (2C), 110.2, 107.9, 55.4, 52.5, 41.4, 37.9, 32.8. IR
(KCl): 1719, 1643, 1587, 1208, 1075, 1028, 740, 723 cm−1. Anal. Cald. for C17H18O5S:
C, 61.06; H, 5.43; S, 9.59. Found: C, 59.90; H, 5.42; S, 9.44.
Methyl 2-(3-(2-chlorophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3p). Vis-
cous oil, yield 84%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.43–7.31 (m, 5H), 6.29–6.25
(m, 2H), 4.73 (t, J = 7.3 Hz, 1H), 3.76 (s, 3H), 3.69 (dd, J = 17.3, 7.8 Hz, 1H), 3.54 (J =
17.3, 6.9 Hz, 1H), 3.18 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 199.1, 170.5,
152.1, 142.4, 139.1, 138.6, 132.0, 130.0, 129.2, 126.8, 110.2, 106.1, 52.4, 41.1, 38.0, 32.7.
IR (KCl): 1723, 1638, 1581, 1218, 1023, 989, 792, 733 cm−1. Anal. Cald. for C16H15ClO4S:
C, 56.72; H, 4.46; S, 9.46. Found: C, 56.68; H, 4.45; S, 9.39.
Methyl 2-(3-(3-chlorophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3q). Vis-
cous oil, yield 88%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.89 (t, J = 1.8 Hz 1H), 7.82
(dt, J = 8.1, 1.5 Hz, 1H), 7.53 (dq, J = 8.0, 1.0 Hz, 1H), 7.37–7.34 (m, 2H), 6.29–6.27
(m, 2H), 4.79 (dd, J = 7.7, 6.5 Hz, 1H), 3.68 (dd, J = 17.5, 7.8 Hz, 1H), 3.69 (s, 3H), 3.53
(dd, J = 17.5, 6.4 Hz, 1H), 3.19 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 194.8,
170.6, 152.1, 142.4, 137.9, 135.0, 133.3, 130.0, 128.2, 126.2, 110.3, 108.1, 52.6, 42.0, 37.6,
32.8. IR (KCl): 1734, 1644, 1601, 1552, 1213, 1030, 1008, 763, 748 cm−1. Anal. Cald. for
C16H15ClO4S: C, 56.72; H, 4.46; S, 9.46. Found: C, 56.60; H, 4.39; S, 9.42.
Methyl 2-(3-(4-chlorophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3r). Vis-
cous oil, yield 94%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.89 (d, J = 8.4 Hz 2H, AAꢁ),
7.43 (d, J = 8.4 Hz 2H, XXꢁ), 7.34 (s, 1H), 6.29–6.27 (m, 2H), 4.79 (t, J = 7.4 Hz, 1H),
3.71 (dd, J = 17.4, 7.9 Hz, 1H), 3.69 (s, 3H), 3.53 (dd, J = 17.4, 6.3 Hz, 1H), 3.19 (s, 2H).
13C-NMR (100 MHz, CDCl3, ppm): δ = 194.9, 170.6, 152.2, 142.4, 139.9, 134.7, 129.5
(2C), 129.0 (2C), 110.3, 108.1, 52.5, 41.8, 37.6, 32.8. IR (KCl): 1765, 1702, 1649, 1534,

¨
M. BURCU GURDERE ET AL.
896
1216, 1014, 1001, 795, 767 cm−1. Anal. Cald. for C16H15ClO4S: C, 56.72; H, 4.46; S, 9.46.
Found: C, 56.68; H, 4.39; S, 9.40.
Methyl 2-(3-(2-bromophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3s). Vis-
cous oil, yield 88%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.57–7.25 (m, 4H), 7.32 (s,
1H), 6.26 (d, J = 9.4, 2H), 4.71(t, J = 7.4 Hz, 1H), 3.74 (s, 3H), 3.78–3.70 (dd, J = 17.5,
7.8 Hz, 1H), 3.56–3.49 (dd, J = 17.5, 6.4 Hz, 1H), 3.16 (s, 2H). 13C-NMR (100 MHz,
CDCl3, ppm): δ = 199.8, 170.4, 151.9, 142.4, 140.8, 133.7, 131.8, 128.8, 127.4, 118.2,
110.2, 108.2, 52.5, 45.8, 41.1, 32.7. IR (KCl): 1723, 1600, 1546, 1220, 1041, 1118, 791,
722 cm−1. Anal. Cald. for C16H15BrO4S: C, 50.14; H, 3.94; S, 8.37. Found: C, 49.95; H,
3.97; S, 8.11.
Methyl 2-(3-(3-bromophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3t). Vis-
1
cous oil, yield 73%. H-NMR (400 MHz, CDCl3, ppm): δ = 8.07 (t, J = 1.7 Hz, 1H),
7.87–7.85 (m, 1H), 7.70–7.67 (m, 1H), 7.36–7.32 (m, 2H), 6.29–6.27 (m, 2H), 4.80 (dd,
J = 7.6, 6.5 Hz, 1H), 3.70 (s, 3H), 3.74 (dd, J = 17.5, 7.8 Hz, 1H), 3.53 (dd, J = 17.5,
6.4 Hz, 1H), 3.19 (s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 195.4, 170.6, 152.1,
142.4, 138.1, 135.4, 128.6, 127.6, 124.3, 122.1, 110.3, 108.1, 52.6, 42.0, 37.6, 32.8. IR
(KCl): 1707, 1614, 1598, 1232, 1065, 1118, 795, 718 cm−1. Anal. Cald. for C16H15BrO4S:
C, 50.14; H, 3.94; S, 8.37. Found: C, 49.90; H, 3.62; S, 8.30.
Methyl 2-(3-(4-bromophenyl)-1-(furan-2-yl)-3-oxopropylthio) acetate (3u). Vis-
cous oil, yield 94%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.77 (d, J = 8.6 Hz 2H, AAꢁ),
7.55 (d, J = 8.6 Hz 2H, XXꢁ), 7.32–7.31 (m, 1H), 6.26–6.24 (m, 2H), 4.77 (t, J = 8.6 Hz,
1H), 3.66 (dd, J = 17.4, 7.8 Hz, 1H), 3.6 (s, 3H), 3.50 (dd, J = 17.4, 6.4 Hz, 1H), 3.16
(s, 2H). 13C-NMR (100 MHz, CDCl3, ppm): δ = 195.0, 170.6, 152.2, 142.4, 135.1, 131.9
(2C), 129.6 (2C), 127.8, 110.3, 108.0, 52.5, 41.8, 37.6, 32.7. IR (KCl): 1726, 1645, 1551,
1229, 1018, 1002, 780, 733 cm−1. Anal. Cald. for C16H15BrO4S: C, 50.14; H, 3.94; S, 8.37.
Found: C, 49.97; H, 3.86; S, 8.34.
Methyl 2-(1-(furan-2-yl)-3-(2-hydroxyphenyl)-3-oxopropylthio) acetate (3v).
1
Viscous oil, yield 89%. H-NMR (400 MHz, CDCl3, ppm): δ = 7.52–7.49 (m, 1H),
7.45–7.39 (m, 2H), 7.27–7.23 (m, 2H), 6.29–6.25 (m, 2H), 5.31 (dd, J = 9.2, 6.9 Hz, 1H),
3.8 (J = 17.8, 9.3 Hz, 1H), 3.76 (J = 17.8, 6.9 Hz, 1H), 2.96 (s, 3H). 13C-NMR (100 MHz,
CDCl3, ppm): δ = 205.9, 156.1, 153.7, 146.4, 143.0, 130.3, 124.8, 124.7, 117.2, 116.4,
110.5, 106.8, 44.2, 39.7, 29.5, 28.4. IR (KCl): 1718, 1604, 1558, 1218, 1037, 1008, 769,
748 cm−1. Anal. Cald. for C16H16O5S: C, 59.99; H, 5.03; S, 10.01. Found: C, 59.82; H,
5.02; S, 9.97.
Methyl 2-(3-(furan-2-yl)-1-(2-methoxyphenyl)-3-oxopropylthio) acetate (3w).
Yellow crystals, yield 68%, M.P.: 196 ◦C–198 ◦C. 1H-NMR (400 MHz, CDCl3, ppm): δ =
7.54 (s, 1H), 7.35 (d, J = 7.2 Hz, 1H), 7.19–7.15 (m, 2H), 6.88 (t, J = 7.4 Hz, 1H), 6.82 (d,
J = 8.0 Hz, 1H), 6.47 (br d, J = 2.0 Hz, 1H), 5.01 (t, J = 7.4 Hz, 1H), 3.80 (s, 3H), 3.58
(s, 3H), 3.50 (dd, J = 16.4 Hz, J = 7.8 Hz, 1H, A part of AB system 1), 3.37 (dd, J = 16.4
Hz, J = 7.0 Hz, 1H, B part of AB system 1), 3.20 (d, J = 7.8 Hz, 1H, A part of AB system
2), 3.16 (d, J = 7.8 Hz, 1H, A part of AB system 2). 13C-NMR (100 MHz, CDCl3, ppm):
δ = 186.0, 170.7, 157.0, 152.6, 146.6, 128.8, 128.6, 128.4, 120.6, 117.5, 112.3, 111.0,
55.6, 52.3, 43.8, 39.4, 33.6. IR (KCl): 3064, 3031, 2983, 2946, 2883, 2834, 1733, 1683,
1590, 1558, 1508, 1386, 1288, 1245, 1160, 1122, 1058, 1004, 921, 881, 759, 703 cm−1
Anal. Cald. for C17H18O5S: C, 61.06; H, 5.43; S, 9.59. Found: C, 61.03; H, 5.45; S, 9.52.
.
Methyl 2-(1-(4-bromophenyl)-3-(furan-2-yl)-3-oxopropylthio) acetate (3x). Vis-
cous oil, yield 84%. 1H-NMR (400 MHz, CDCl3, ppm): δ = 7.61 (s, 1H), 7.41 (d, J = 8.4
Hz, 2H, AAꢁ part of AAꢁBBꢁ system), 7.29 (d, J = 8.4 Hz, 2H, BBꢁ part of AAꢁBBꢁ system),

IODINE-CATALYZED ADDITION OF METHYL THIOGLYCOLATE TO CHALCONES 897
7.16 (d, J = 3.6 Hz, 1H), 6.50 (t, J = 1.8 Hz, 1H), 4.66 (t, J = 7.4 Hz, 1H), 3.65 (s, 3H),
3.38 (d, J = 7.2 Hz, 2H), 3.51 (d, J = 13.6 Hz, 1H, A part of AB system), 2.96 (d, J =
13.6 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 185.1, 170.4,
152.3, 146.7, 139.6, 131.7 (2C), 129.8 (2C), 121.4, 117.6, 112.5, 52.5, 44.2, 43.9, 32.8. IR
(KCl): 3131, 3062, 3023, 2994, 2950, 2848, 1735, 1673, 1567, 1486, 1467, 1434, 1396,
1278, 1159, 1072, 1010, 987, 883, 763, 719, 593 cm−1. Anal. Cald. for C16H15BrO4S: C,
50.14; H, 3.94; S, 8.37. Found: C, 50.18; H, 3.90; S, 8.25.
Methyl 2-(3-(3-bromophenyl)-3-oxo-1-(thiophen-2-yl)propylthio) acetate (3y).
1
Brown crystals, yield 68%, M.P.: 58 ◦C–60 ◦C. H-NMR (400 MHz, CDCl3, ppm):
δ = 7.97 (s, 1H), 7.77 (d, J = 7.6 Hz, 1H), 7.58 (d, J = 7.2 Hz, 1H), 7.26–7.14 (m,
2H), 7.02–6.98 (m, 1H), 6.83 (d, J = 3.6 Hz, 1H), 5.01 (t, J = 7.4 Hz, 1H), 3.62 (s, 3H),
3.55–3.53 (m, 2H), 3.15 (d, J = 15.4 Hz, 1H, A part of AB system), 3.08 (d, J = 15.4 Hz,
1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 194.5, 170.5, 144.8,
138.1, 136.2, 131.1, 130.3, 126.7, 126.6, 126.5, 125.2, 123.1, 52.5, 45.8, 39.9, 32.9. IR
(KCl): 3095, 3066, 2950, 2902, 1733, 1685, 1592, 1560, 1417, 1282, 1207, 1039, 970,
796, 709, 671 cm−1. Anal. Cald. for C16H15BrO3S2: C, 48.12; H, 3.79; S, 16.06. Found: C,
48.18; H, 3.71; S, 16.14.
Methyl 2-(3-(4-bromophenyl)-3-oxo-1-(t◦hiophen-2-yl)propylthio) acetate (3z).
◦
1
Brown crystals, yield 73%, M.P.: 127 C–129 C. H-NMR (400 MHz, CDCl3, ppm):
δ = 7.67 (d, J = 7.4 Hz, 2H, AAꢁ part of AAꢁBBꢁ system), 7.45 (d, J = 7.4 Hz, 2H, BBꢁ
part of AAꢁBBꢁ system), 7.10 (d, J = 4.4 Hz, 1H), 6.94 (s, 1H), 6.78 (s, 1H), 4.96 (t, J =
6.8 Hz, 1H), 3.57 (s, 3H), 3.49 (s, 2H), 3.10 (d, J = 7.2 Hz, 1H, A part of AB system), 3.04
(d, J = 7.2 Hz, 1H, B part of AB system). 13C-NMR (100 MHz, CDCl3, ppm): δ = 194.9,
170.4, 144.8, 131.9 (2C), 131.8, 129.9, 129.6 (2C), 128.5, 126.5, 125.2, 52.4, 45.6, 39.9,
32.9. IR (KCl): 3102, 3081, 3068, 2992, 2950, 1733, 1683, 1650, 1585, 1560, 1396, 1328,
1278, 1070, 1029, 1006, 971, 819, 709 cm−1. Anal. Cald. for C16H15BrO3S2: C, 48.12; H,
3.79; S, 16.06. Found: C, 48.08; H, 3.65; S, 16.02.
ACKNOWLEDGMENT
The authors are indebted to the Technical Research Council of Turkey (Grant
TUBITAK-106T103) for the financial support provided for this work.
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