Visible-Light-Mediated Organocatalyzed Thiol-Ene Reaction Initiated by a Proton-Coupled Electron Transfer

Article abstract of DOI:10.1021/acs.joc.9b01331

A convenient method for performing a thiol-ene reaction is described. The reaction is performed under blue-light irradiation and catalyzed by photoactive Lewis basic molecules such as acridine orange or naphthalene-fused N-acylbenzimidazole. It is believed that the process is initiated by a proton-coupled electron transfer process within the complex between the thiol and the Lewis basic catalyst.

Full text of DOI:10.1021/acs.joc.9b01331

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Note
Visible Light-Mediated Organocatalyzed Thiol-Ene
Reaction Initiated by Proton-Coupled Electron Transfer
Vitalij V. Levin, and Alexander D. Dilman
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.9b01331 • Publication Date (Web): 26 May 2019
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Page 1 of 23
The Journal of Organic Chemistry
Visible Light-Mediated Organocatalyzed Thiol-Ene Reaction
Initiated by Proton-Coupled Electron Transfer
Vitalij V. Levin, Alexander D. Dilman*
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N. D. Zelinsky Institute of Organic Chemistry, 119991 Moscow, Leninsky prosp. 47, Russian Federation
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h
Cat. (0.5%),

RS
RSH
+
Y
Y
N
*
PCET
N
RS
H
RS
N
H
+
ABSTRACT: A convenient method for performing thiol-ene reaction is described. The reaction is
performed under blue light irradiation and catalyzed by photoactive Lewis basic molecules such as
acridine orange or naphthalene-fused N-acylbenzimidazole. It is believed that the process is initiated by
a proton-coupled electron transfer within the complex between the thiol and the Lewis basic catalyst.
Thiol-ene reaction has emerged as a powerful tool for stitching together two molecules.1 This
process has been exploited in many fields such as polymer and materials sciences,2 biological
applications,3 and others.4 While thiols and alkenes are typically unreactive towards each other, their
interaction can be triggered by various initiators leading to a radical addition reaction. This atom-
economic process is tolerant to a variety of functional groups, and, owing to its potential efficiency it
can also be considered as a click-reaction.5 Herein we report a convenient protocol for performing thiol-
ene reaction featuring mild conditions, use of small amounts (less than 1%) of readily accessible non-
metal catalyst, a close to stoichiometric ratio of coupling components, and visible light as initiator.6,7
Photocatalytic versions of thiol-ene reaction have previously been reported based on application of
precious metal photocatalysts,8 metal oxides as light absorbing systems,9 as well as acridinium salts10
and benzophenone or 2,2-dimethoxyphenyl acetophenone.11,12 A key initiating step in these reactions is
the hydrogen atom abstraction from the thiol to generate S-centered radical, which subsequently enters
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into a chain process.13 For this purpose, an additive such as bromotrichloromethane to generate an
activator species, is used (Scheme 1).
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Scheme 1. Generation of thiyl radicals.
9
h, activator
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RSH
RS
Previous work:
activator = Cl3C , R2N , redox
This work:
LB
Y
h, PCET
RSH
LB
RS
+
H
RS
H
LB
RS
RS
RS
H
LB
Y
H
LB
RSH
Y
In this work, the thiyl radical is generated via proton-coupled electron transfer (PCET). Indeed, a
simultaneous exchange of a proton and an electron is frequently encountered in biological processes,
and is increasingly used in synthetic transformations.14,15 As a catalyst we propose to use a photoactive
Lewis basic species capable of binding to acidic thiol (Scheme 1). Under irradiation, the PCET step can
take place, which can be realized via different pathways (vide infra), resulting in generation of thiyl
radical. The latter can be involved in a typical chain mechanism involving H-atom transfer between the
C-centered radical and thiol (left part). Alternatively, the alkyl radical can abstract hydrogen atom from
a highly reactive radical originating from PCET (right part). In this step, the radical chain is terminated
along with the regeneration of Lewis basic photocatalyst.
tert-Butylthiol (1a) and allylacetate (2a) were selected as model substrates and their coupling was
evaluated (Table 1). A small excess of thiol (1.2 equiv) was used throughout this work, which facilitates
product isolation. Reactions were performed in cyclohexane under argon atmosphere for one hour by
irradiation with blue light, and conversion of the alkene was determined by GC analysis. There was no
reaction without catalyst, but addition of 0.5 mol% of readily accessible benzimidazole-based
compound 416 caused noticeable conversion of the alkene (entries 1 and 2). With more basic catalyst,
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The Journal of Organic Chemistry
acridine orange (5), the reaction was faster, leading to virtually complete conversion after 5 hours (entry
4). Experiments with more acidic thiols such as benzylthiol, methyl thioglycolate and thioacetic acid
showed that these reactions proceed faster, and even catalyst 4 can be applied (entries 5-9). When the
reaction was performed in the air atmosphere, there was no deleterious effect to the product yield, while
sufloxide by-products were not detected by GC-MS analysis.17 At the same time, household lamp as a
light source in combination with catalyst 4 was notably less efficient compared to 400 LED (see entry
7).
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Table 1. Optimization studies.
LB (0.5%)
OAc
RS
OAc
RSH
+
cyclohexane
1
(1.2 equiv)
2a
3a
b
, R = t-Bu
, R = Bn
blue LED, rt, 1 h
c
d
, R = MeO2CCH2
, R = Ac
O
N
Me2N
N
NMe2
N
5
4
#
Thiol
LB
-
Product
3a
Conv. of 2a, %a
1
t-BuSH (1a)
t-BuSH (1a)
t-BuSH (1a)
t-BuSH (1a)
BnSH (1b)
BnSH (1b)
BnSH (1b)
< 1
2
4
3a
17
3
5
3a
67
4b
5
5
3a
98 (86c)
99 (91c)
46
5
3b
6
4
3b
7d
8
4
3b
39
MeO2CCH2SH (1c)
AcSH (1d)
4
3c
100 (97c)
100 (95c)
9
4
3d
a Determined by GC. b Reaction time 5 h. c Yield of 3. d Irradiation with household lamp, 15W CFL.
Using photocatalysts 4 and 5, a series of thiols were combined with alkenes (Table 2). The reaction
has wide scope with respect to both components affording, typically, high yields of products. Indeed,
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aliphatic and aromatic thiols, as well as those bearing unprotected hydroxy or amino groups, worked
well in this process. At the same time, terminal and internal alkenes can be used leading to the product
with regioselectivity characteristic for radical addition. The alkene component may contain hydroxyl,
ester, aldehyde, keto, and acetal groups. Difluorinated alkenes, which are readily available from
aldehydes via Wittig olefination,18 also afforded corresponding products in good yields (entries 5, 19,
20). Electron-rich alkenes such as dihydropyrane and N-vinylimidazole also were successfully
employed (entries 11 and 13). Notably, cinnamyl chloride, bearing a reactive C-Cl bond, gave the
desired addition product (entry 25). Concerning thio-component, thioacids were most reactive, affording
addition product even with tetrasubstituted double bond (entry 31). Though most reactions were
complete within few hours, for some examples longer time was required. For substrates having more
acidic S-H fragment such as thioacids, catalyst 4 was successfully used, whereas acridine orange 5
worked well for less acidic aliphatic thiols. The disadvantage of acridine orange is that at longer
reaction times (> 6 h), it can lose its activity as reflected by noticeable rate retardation.
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The Journal of Organic Chemistry
Table 2. Photocatalyzed thiol-ene reaction.
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4
R1S
R2
LB (0.5%)
R4
R1SH
R4
R2
+
cyclohexane
blue LED, rt
R3
R3
5
6
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#
1
2
Product
LB Time, Yield,
#
Product
LB Time, Yield,
h
3
%
h
1
%
S
Ph
3e
3f
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5
85
17
18
3u
3v
4
5
99
MeO2C
MeO2C
S
S
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S
Ph
2
96
92
24
1
92
98
NH2
S
3a
3g
4
0.25
19
3w
5
MeO2C
S
Ph
Ph
F
F
Cl
HO
S
C6F5
Ph
4
5
3h
3i
5
4
1.5
48
98
92
20
21
3x
3y
3z
4
4
4
18
18
98
98
F
F
MeO2C
MeO2C
S
S
S
S
Ph
C6F5
F
F
O
Ph
Ph
S
OH
Ph
6
7
3j
5
5
5
1
90
99
22
23
0.5
1
98
98
S
S
OH
3k
3za 4
3zb 4
3zc 4
O
O
S
S
Ph
Ph
Ph
OEt
8
9
3l
5
2
1
92
98
24
25
1
97
92
OEt
S
S
O
Cl
O
Ph
3m 5
15
S
OH
Ph
Ph
Ph
Ph
Ph
10
11
12
13
3n
3o
3p
3q
4
5
5
5
18
18
2
90
74
58
88
26
3zd 4
3ze 4
18
2
90
91
77
90
O
O
S
O
O
S
S
S
O
27b
28
S
N
O
O
N
O
3zf
4
18
15
S
Ph
MeO2C
O
S
29a
3zg 4
3zh 4
N
1
N
Ph
Ph
S
O
O
O
S
S
S
Ph
14
15
3r
3s
5
4
3
4
99
97
30
31
2
99
77
Ph
Ph
Ph
S
3zi
3zj
4
4
12
HO
Ph
16
3t
5
1
98
32
2
82
Cl
S
MeO2C
a CH2Cl2 was used as solvent. b EtOAc was used as solvent.
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Mode of action of the Lewis basic photocatalysts deserves additional comments. PCET process for
the generation of thiyl radicals can be realized via different pathways18 (Scheme 2). Consecutive proton
transfer (PT) and electron transfer (ET) steps (top and bottom paths), as well as concerted proton-
electron transfer (CPET) should be considered. In general, given that the reaction proceeds efficiently in
non-polar solvent (cyclohexane), the formation of charged species seems unfavorable. In the literature,
for an analogous system involving light mediated PCET process between acridine orange and a phenol,
the CPET mechanism was suggested based on transient absorption spectroscopy measurements.19
Correspondingly, the concerted pathway is likely in case of thiols. On the other hand, the mechanism
may depend on particular thiol/catalyst combination. Indeed, it was noted that reactions proceed faster
with more acidic thiols. This observation suggests some thiol/catalyst interaction, which would precede
the electron transfer step.20,21
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Scheme 2. PCET process.
RS
H
LB
h
PT
ET
ET
PT
RSH
+
CPET
RS
H LB
RS
H LB
h
LB
h
RSH LB
We proposed that the presence of additional Lewis basic species capable of binding to the thiol in
competition with the photocatalyst may influence on the reaction efficiency. Indeed, when pyridine (2
equiv) was present in the mixture of benzylthiol 1b with allylacetate 2a in the presence of catalyst 4,
only 23% conversion of 2a was noted compared to 46% without pyridine under otherwise identical
conditions (30 min reaction time).
To obtain some insights on the interaction of catalysts 4 and 5 with thiols, their combinations were
evaluated spectroscopically. Thus, chemical shifts of 4 in 1H NMR spectrum (in CDCl3) and its UV-vis
absorption spectrum (in CH2Cl2) were unaffected by addition of excess of strongly acidic thioacetic
acid. However, AcSH caused quenching of fluorescence of 4 (Stern-Volmer analysis) thereby
supporting the interaction of the catalyst's excited state with the thiol. A combination of more basic
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The Journal of Organic Chemistry
catalyst 5 with less acidic benzylthiol 1b in cyclohexane behaved similarly (no change in NMR, and
UV-vis, observation of Stern-Volmer fluorescence quenching). However, in more polar acetonitrile,
gradual addition of large excess of the thiol to 5 led to notable change in its absorption spectrum (see
Supporting Information for details). The difference in spectra in cyclohexane and acetonitrile may be
associated with the propensity of formation of protonated form of 5 (5·H+) in more polar solvent, and,
therefore, another mechanism involving oxidation of the thiol by 5·H+ may be operative in this case.
However, when a typical reaction of benzylthiol 1b with allylacetate 2a mediated by 5 was performed in
acetonitrile, the reaction proceeded notably slower compared to that in cyclohexane. This means that the
oxidation of the thiol by 5·H+ cannot be the dominating reaction pathway.
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The chain character of the process was supported by the measurement of the quantum yield for the
reaction of benzylthiol 1b with allylacetate 2a, which gave the value of 6.22 However, the light is
necessary to maintain this reaction, since in a light/dark sequence, there was a significant retardation in
the dark periods (see Supporting Information). This points to the chain interruption via H-atom transfer
from highly reactive H-LB radical species to the alkyl radical23 (see Scheme 1).
In summary, a convenient protocol for the visible light-promoted thiol-ene click reaction is
described. The method has wide substrate scope, and prescribes the use of close to stoichiometric ratio
of thiol and alkene. The Lewis basic nature of the photocatalyst is believed to be the key issue
responsible for the reaction efficiency.
EXPERIMENTAL SECTION
General Methods: Column chromatography was carried out employing silica gel (230‐400 mesh).
Precoated silica gel plates F‐254 were used for thin‐layer analytical chromatography visualizing with
UV and/or acidic aq. KMnO4 solution. High resolution mass spectra (HRMS) were measured using
electrospray ionization (ESI) and time‐of‐flight (TOF) mass analyzer (Bruker MicrOTOF II). The
measurements were done in a positive ion mode (interface capillary voltage –4500 V) or in a negative
ion mode (3200 V); mass range from m/z 50 to m/z 3000. For NMR measurements, Bruker AM300
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spectrometer was used. Fluorescence and absorption spectra were recorded on a Fluorat-02-Panorama
spectrofluorometer (Lumex Instruments). For irradiation, a strip of light emitting diodes
(SMD2835‐120LED 1M‐Blue, 12V, 24W/m, 465 nm) was used. Reactions were performed in DURAN
culture tubes (Roth cat. # K248.1, outside diameter 12 mm). Chemicals were purchased from Acros.
(2,2-Difluoroethenyl)benzene,24 4-phenyl-2-methylbut-1-ene,25 1-phenylbut-3-en-1-ol,26 and N-
allylphthalimide27 were prepared according to literature procedures.
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1,8-Naphthoylene-1',2'-benzimidazole (4).28 Naphthalic anhydride (4.0 g, 20 mmol) and o-
phenylenediamine (2.38 g, 22 mmol) were mixed in 15 mL of propionic acid. The mixture was heated
by a hot plate to 135 °C (the temperature was measured by a thermometer immersed in the reaction
mixture) and was stirred at this temperature for 30 min. The heating bath was removed, the stirring was
discontinued, and the mixture was allowed to cool to room temperature, and was kept overnight to effect
crystallization. The crystals were filtered, washed twice with acetic acid and twice with methyl tert-
butyl ether, and dried. The obtained crystals were successively recrystallized from toluene and 2-
ethoxyethanol. Yield 4.38 g (80%). Mp 192–193°C. 1H NMR (300 MHz, CDCl3) δ: 7.43–7.54 (m, 2H),
7.70–7.80 (m, 2H), 7.83–7.91 (m, 1H), 8.07 (d, 1H, J = 8.2 Hz), 8.21 (d, 1H, J = 8.1 Hz), 8.49–8.57 (m,
1H), 8.72 (d, 1H, J = 7.2 Hz), 8.77 (d, 1H, J = 7.2 Hz). 13C{1H} NMR (75 MHz, CDCl3) δ: 160.6 149.3,
143.9, 135.3, 132.2, 132.0, 131.8, 131.6, 127.4, 127.1, 127.0, 126.9, 125.8, 125.5, 123.2, 120.6, 120.1,
116.0.
Thiol-ene reaction (General procedure). In a screw-cap tube, alkene (1.5 mmol) and thiol (1.8 mmol)
were mixed under argon in 2 mL of degassed solvent (for all compounds 3 except 3g,ze,zg, solvent -
cyclohexane; for 3g,zg, solvent - CH2Cl2; for 3ze, solvent - EtOAc). Photocatalyst 4 or 5 (0.0075 mmol,
0.5%) was added. The tube was sealed and then stirred with irradiation by a strip of blue LED for the
time indicated in Table 2. During irradiation the mixture was cooled with room temperature water (for
the reaction set-up, see Supporting information). For all compounds 3 except 3g,ze,zg, the reaction
mixture was transferred to a silica gel column, which was eluted with hexanes/EtOAc. For compounds
3g,zg, the reaction mixture was evaporated under vacuum, and the residue was purified by
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The Journal of Organic Chemistry
chromatography on silica gel with hexanes/EtOAc. For compound 3ze, the reaction mixture was eluted
with EtOAc through a silica gel pad, evaporated, and the residue was recrystallized from n-
heptane/EtOAc (2/1).
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4
5
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7
8
9
3-(tert-Butylthio)propyl acetate (3a). Yield 245 mg (86%). Colorless oil. Chromatography:
hexanes/EtOAc, 15/1. Rf 0.22 (hexanes/EtOAc, 15/1). 1H NMR (300 MHz, CDCl3) δ: 1.29 (s, 9H), 1.83
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(quint, 2H, J = 6.7 Hz), 1.99 (s, 3H), 2.52 (t, 2H, J = 6.3 Hz), 4.09 (t, 2H, J = 7.4 Hz, 2H). C{1H}
NMR (75 MHz, CDCl3) δ: 20.9, 24.7, 29.0, 30.9, 42.0, 63.3, 170.8. HRMS (ESI): Calcd for
C9H18NaO2S (M+Na) 213.0920; found 213.0929.
3-(Benzylthio)propyl acetate (3b).29 Yield 306 mg (91%). Colorless oil. Chromatography: gradient
1
elution hexanes/EtOAc, 15 /1→10/1. Rf 0.24 (hexanes/EtOAc, 10/1). H NMR (300 MHz, CDCl3) δ:
1.88 (quint, 2H, J = 7.0 Hz), 2.04 (s, 3H), 2.49 (t, 2H, J = 7.3 Hz), 3.73 (s, 2H), 4.13 (t, 2H, J = 6.4 Hz),
7.22–7.36 (m, 5H). 13C{1H} NMR (75 MHz, CDCl3) δ: 20.9, 27.6, 28.3, 36.2, 63.1, 127.0, 128.5, 128.9,
138.3, 171.0.
Methyl 2-[(3-acetoxypropyl)thio]acetate (3c). Yield 300 mg (97%). Colorless oil. Chromatography:
hexanes/EtOAc, 4/1. Rf 0.23 (hexanes/EtOAc, 4/1). 1H NMR (300 MHz, CDCl3) δ: 1.85 (quint, 2H, J =
6.5 Hz), 1.97 (s, 3H), 2.62 (t, 2H, J = 7.3 Hz), 3.15 (s, 2H), 3.65 (s, 3H), 4.07 (t, 2H, J = 6.3 Hz).
13C{1H} NMR (75 MHz, CDCl3) δ: 20.8, 28.0, 28.9, 33.2, 52.2, 62.7, 170.6, 170.7. HRMS (ESI): Calcd
for C8H14NaO4S (M+Na) 229.0505; found 229.0500.
3-(Acetylthio)propyl acetate (3d). Yield 251 mg (95%). Colorless oil. Chromatography:
hexanes/EtOAc, 5/1. Rf 0. 31 (hexanes/EtOAc, 5/1). 1H NMR (300 MHz, CDCl3) δ: 1.84 (quint, 2H, J =
7.0 Hz), 1.99 (s, 3H), 2.26 (s, 3H), 2.87 (t, 2H, J = 7.2 Hz), 4.04 (t, 2H, J = 6.2 Hz). 13C{1H} NMR (75
MHz, CDCl3) δ: 20.8, 25.6, 28.6, 30.5, 62.7, 170.8, 195.3. HRMS (ESI): Calcd for C7H12NaO3S
(M+Na) 199.0399; found 199.0405.
Methyl 2-[(2,4,4-trimethylpentyl)thio]acetate (3e). Yield 337 mg (85%). Colorless oil.
Chromatography: hexanes/EtOAc, 15/1. Rf 0.28 (hexanes/EtOAc, 15/1). 1H NMR (300 MHz, CDCl3) δ:
0.89 (s, 9H), 1.01 (d, 3H, J = 6.6 Hz). 1.09 (dd, 1H, J = 13.9; 6.6 Hz), 1.35 (dd, 1H, J = 13,9; 3.7 Hz),
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1.65–1.80 (m, 1H), 2.44 (dd, 1H, J = 12.3; 8.1 Hz), 2.61 (dd, 1H, J = 12.3; 5.9 Hz), 3.19 (s, 2H), 3.71 (s,
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3H). C{1H} NMR (75 MHz, CDCl3) δ: 22.1, 29.3, 29.9, 31.0, 33.8, 42.4, 50.2, 52.2, 171.0. HRMS
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(ESI): Calcd for C11H22NaO2S (M+Na) 241.1233; found 241.1235
Methyl 2-(cyclohexylthio)acetate (3f).30 Yield 721 mg (96%). Colorless oil. Chromatography:
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hexanes/EtOAc, 12/1. Rf 0.33 (hexanes/EtOAc, 10/1). H NMR (300 MHz, CDCl3) δ: 1.20–1.40 (m,
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5H), 1.56–1.66 (m, 1H), 1.70–1.84 (m, 2H), 1.91–2.05 (m, 2H), 2.73–2.86 (m, 1H), 3.26 (s, 2H), 3.73
(s, 3H). 13C{1H} NMR (75MHz, CDCl3) δ: 25.8, 26.0, 31.8, 33.1, 44.0, 52.4, 171.3.
Methyl 2-[(4-phenylbutyl)thio]acetate (3g). Yield 392 mg (92%). Colorless oil. Chromatography:
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hexanes/EtOAc, 10/1. Rf 0.26 (hexanes/EtOAc, 10/1). H NMR (300 MHz, CDCl3) δ: 1.61–1.82 (m,
4H), 2.66 (t, 2H, J = 7.3 Hz), 2.69 (t, 2H, J = 7.2 Hz), 3.23 (s, 2H), 3.75 (s, 3H). 7.17–7.24 (m, 3H),
7.27–7.35 (m, 2H). 13C{1H} NMR (75 MHz, CDCl3) δ: 28.5, 30.4, 32.6, 33.5, 35.4, 52.3, 125.8, 128.3,
128.4, 142.1, 171.0. HRMS (ESI): Calcd for C13H18NaO2S (M+Na) 261.0920; found 261.0919.
Methyl 2-{[3-(2-hydroxyphenyl)propyl]thio}acetate (3h). Yield 353 mg (98%). Colorless oil.
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Chromatography: hexanes/EtOAc, 3/1. Rf 0.28 (hexanes/EtOAc, 3/1). H NMR (300 MHz, CDCl3) δ:
1.95 (quint, 2H, J = 7.5 Hz), 2.69 (t, 2H, J = 7.3 Hz), 2.75 (t, 2H, J = 7.5 Hz), 3.27 (s, 2H), 3.74 (s, 3H),
6.22 (s, 1H), 6.82 (dd, 1H, J = 8.1; 1.1 Hz), 6.86 (td, 1H, J = 7.5; 1.3 Hz), 7.08 (td, 1H, J = 7.7; 1.8 Hz),
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7.12 (dd, 1H, J = 7.5; 1.5 Hz). C{1H} NMR (75 MHz, CDCl3) δ: 28.8, 28.9, 32.4, 33.5, 52.6, 115.5,
120.6, 127.4, 127.5, 130.4, 154.0, 171.7. HRMS (ESI): Calcd for C12H16NaO3S (M+Na) 263.0712;
found 263.0707 .
Methyl 2-[(1,1-difluoro-2-phenylethyl)thio]acetate (3i). Yield 339 mg (92%). Colorless oil.
Chromatography: hexanes/EtOAc, 10/1. Rf 0.28 (hexanes/EtOAc, 10/1). 1H NMR (300 MHz, CDCl3) δ:
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3.47 (t, 2H, J = 14.8 Hz), 3.61 (s, 2H), 3.76 (s, 3H), 7.30 – 7.41 (m, 5H). C{1H} NMR (75 MHz,
CDCl3) δ: 29.9 (t, J = 4.4 Hz), 45.2 (t, J = 23.7 Hz), 52.7, 128.0, 128.6, 129.3 (t, J = 279.7 Hz), 130.5,
131.5 (t, J = 3.6 Hz), 169.5. 19F NMR (282 MHz, CDCl3) δ: -73.9 (t, J = 14.8 Hz). HRMS (ESI): Calcd
for C11H12F2NaO2S (M+Na) 269.0418; found 269.0427.
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3-(Benzylthio)propan-1-ol (3j).8a Yield 246 mg (90%). Colorless oil. Chromatography:
hexanes/EtOAc, 3/1. Rf 0.15 (hexanes/EtOAc, 3/1). 1H NMR (300 MHz, CDCl3) δ: 1.81 (quint, 2H, J =
6.6 Hz), 2.10 (br s, 1H), 2.55 (t, 2H, J = 7.1 Hz), 3.70 (t, 2H, J = 6.1 Hz), 3.74 (s, 2H), 7.22–7.36 (m,
5H). 13C{1H} NMR (75MHz, CDCl3) δ: 28.0, 31.6, 36.3, 61.6, 127.0, 128.5, 128.9, 138.4.
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4-(Benzylthio)pentan-1-ol (3k). Yield 312 mg (99%). Colorless oil. Chromatography: gradient elution
hexanes/EtOAc, 3 /1→2/1. Rf 0.24 (hexanes/EtOAc, 2/1). 1H NMR (300 MHz, CDCl3) δ: 1.36–1.66 (m,
4H), 2.20 (s, 1H), 2.44 (t, 2H, J = 6.9 Hz), 3.60 (t, 2H, J = 6.6 Hz), 3.72 (s, 2H), 7.21–7.35 (m, 5H).
13C{1H} NMR (75 MHz, CDCl3) δ: 25.0, 29.0, 31.3, 32.2, 36.4, 62.5, 126.9, 128.5, 128.9, 138.6. HRMS
(ESI): Calcd for C12H18NaOS (M+Na) 233.0971; found 233.0961
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Benzyl(3,3-diethoxypropyl)sulfane (3l). Yield 350 mg (92%). Colorless oil. Chromatography:
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hexanes/EtOAc, 15/1. Rf 0.23 (hexanes/EtOAc, 15/1). H NMR (300 MHz, CDCl3) δ: 1.20 (t, 6H, J =
7.3 Hz), 1.84–1.92 (m, 2H), 2.49 (t, 2H, J = 7.3 Hz), 3.48 (dq, 2H, J = 9.5; 7.3 Hz), 3.64 (dq, 2H, J =
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9.5; 7.3 Hz), 3.72 (s, 2H), 4.58 (t, 1H, J = 5.4 Hz), 7.21–7.30 (m, 1H), 7.30–7.34 (m, 4H). C{1H}
NMR (75 MHz, CDCl3) δ: 15.3, 26.5, 33.4, 36.3, 61.5, 101.7, 126.9, 128.4, 128.9, 138.4. HRMS (ESI):
Calcd for C14H22NaO2S (M+Na) 277.1233; found 277.1232.
6-(Benzylthio)hexan-2-one (3m). Yield 326 mg (98%). Color less oil. Chromatography:
hexanes/EtOAc, 5/1. Rf 0.26 (hexanes/EtOAc, 5/1). 1H NMR (300 MHz, CDCl3) δ: 1.48–1.68 (m, 4H),
2.10 (s, 3H), 2.38 (t, 2H, J = 6.6 Hz), 2.40 (t, 2H, J = 6.6 Hz), 7.20–7.27 (m, 1H), 7.28–7.32 (m, 4H).
13C{1H} NMR (75 MHz, CDCl3) δ: 22.9, 28.6, 29.9, 31.0, 36.2, 43.1, 126.9, 128.4, 128.9, 138.5, 208.5.
HRMS (ESI): Calcd for C13H18NaOS (M+Na) 245.0971; found 245.0980.
4-[3-(Benzylthio)propoxy]benzaldehyde (3n). Yield 387 mg (90%). Colorless oil. Chromatography:
hexanes/EtOAc, 5/1. Rf 0.29 (hexanes/EtOAc, 4/1). 1H NMR (300 MHz, CDCl3) δ: 2.05 (quint, 2H, J =
6.6 Hz), 2.63 (t, 2H, J = 7.1 Hz), 3.74 (s, 2H), 4.10 (t, 2H, J = 6.1 Hz), 6.97 (d, 2H, J = 8.8 Hz), 7.21 –
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7.36 (m, 5H), 7.83 (d, 2H, J = 8.8 Hz), 9.89 (s, 1H). C{1H} NMR (75 MHz, CDCl3) δ: 27.6, 28.6,
36.3, 66.5, 114.7, 127.0, 128.5, 128.8, 130.0, 131.9, 138.2, 163.8, 190.6. HRMS (ESI): Calcd for
C17H18NaO2S (M+Na) 309.0920; found 309.0922.
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3-(Benzylthio)tetrahydro-2H-pyran (3o). Yield 282 mg (74%). Colorless oil. Chromatography:
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hexanes/EtOAc, 10/1. Rf 0.24 (hexanes/EtOAc, 10/1). H NMR (300 MHz, CDCl3) δ: 1.40–1.55 (m,
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1H), 1.60–1.72 (m, 2H), 1.99–2.09 (m, 1H), 2.74 (ddt, 1H, J = 15.0; 14.3; 4.0 Hz), 3.27 (dd, 1H, J =
11.2; 10.1 Hz), 3.34–3.44 (m, 1H), 3.76 (s, 2H), 3.85 (dm, 1H, J = 11.4 Hz), 3.95 (ddd, 1H, J = 11.4;
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4.2; 2.0 Hz), 7.23–7.36 (m, 5H). C{1H} NMR (75 MHz, CDCl3) δ: 26.3, 30.3, 35.2, 40.7, 68.0, 72.5,
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127.1, 128.6, 128.8, 138.6. HRMS (ESI): Calcd for C12H16NaOS (M+Na) 231.0814; found 231.0820.
2-[2-(Benzylthio)ethyl]pyridine (3p). Yield 179 mg (52%). Yellowish oil. Chromatography:
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hexanes/EtOAc, 2/1. Rf 0.2 (hexanes/EtOAc, 2/1). H NMR (300 MHz, CDCl3) δ: 2.87 (t, 2H, J = 7.3
Hz), 3.05 (t, 2H, J = 7.3 Hz), 3.73 (s, 2H), 7.10–7.16 (m, 2H), 7.21–7.36 (m, 5H), 7.60 (td, 1H, J = 7.7;
1.8 Hz), 8.55 (dd, 1H, J =5.2; 1.9 Hz). 13C{1H} NMR (75 MHz, CDCl3) δ: 31.0, 36.4, 38.0, 121.3,
123.0, 126.8, 128.4, 128.7, 136.2, 138.3, 149.3, 159.9. HRMS (ESI): Calcd for C14H16NS (M+H)
230.0998; found 230.0993.
1-[2-(Benzylthio)ethyl]-1H-imidazole (3q). Yield 288 mg (88%). Colorless oil. Chromatography:
hexanes/i-PrOH, 3/1. Rf 0.17 (hexanes/i-PrOH, 3/1). 1H NMR (300 MHz, CDCl3) δ: 2.63 (t, 2H, J = 6.9
Hz), 3.51 (s, 2H), 3.87 (t, 2H, J = 6.9 Hz), 6.91 (s, 1H), 6.99 (s, 1H), 7.16–7.31 (m, 5H), 7.36 (s, 1H).
13C{1H} NMR (75 MHz, CDCl3) δ: 31.9, 36.2, 46.6, 118.6, 127.1, 128.4, 128.6, 129.2, 136.9, 137.5.
HRMS (ESI): Calcd for C12H15N2S (M+H) 219.0950; found 219.0959.
tert-Butyl(4-phenylbutyl)sulfane (3r).31 Yield 330 mg (99%). Colorless oil. Chromatography:
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hexanes/EtOAc, 15/1. Rf 0.50 (hexanes/EtOAc, 15/1). H NMR (300 MHz, CDCl3) δ: 1.37 (s, 9H),
1.62–1.73 (m, 2H), 1.73–1.86 (m, 2H), 2.60 (t, 2H, J = 7.2 Hz), 2.69 (t, 2H, J = 7.4 Hz), 7.19–7.26 (m,
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3H) 7.28–7.36 (m, 2H). C{1H} NMR (75 MHz, CDCl3) δ: 28.3, 29.6, 31.1, 35.7, 41.9, 125.8, 128.8,
142.4.
2-[(4-Phenylbutyl)thio]ethan-1-ol (3s). Yield 306 mg (97%). Colorless oil. Chromatography:
hexanes/EtOAc, 3/1. Rf 0.20 (hexanes/EtOAc, 3/1). 1H NMR (300 MHz, CDCl3) δ: 1.59–1.84 (m, 4H),
2.57 (t, 2H, J = 7.1 Hz), 2.61–2.70 (m, 2H), 2.72 (t, 2H, J = 6.1 Hz), 3.72 (t, 2H, J = 6.3 Hz), 7.17–7.26
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(m, 3H), 7.27–7.36 (m, 2H). 13C{1H} NMR (75 MHz, CDCl3) δ: 29.3, 30.5, 31.6, 35.2, 35.5, 60.5,
125.8, 128.4, 128.4, 142.1. HRMS (ESI): Calcd for C12H18NaOS (M+Na) 233.0971; found 233.0978.
Methyl 3-[(cyclohexylmethyl)thio]propanoate (3t). Yield 318 mg (98%). Colorless oil.
Chromatography: hexanes/EtOAc, 15/1. Rf 0.20 (hexanes/EtOAc, 15/1). 1H NMR (300 MHz, CDCl3) δ:
0.83–0.99 (m, 2H), 1.05–1.29 (m, 3H), 1.36–1.51 (m, 1H), 1.51–1.75 (m, 3H), 1.76–1.87 (m, 2H), 2.40
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(d, 2H, J = 6.9 Hz), 2.58 (t, 2H, J = 7.2 Hz), 2.74 (t, 2H, J = 7.2 Hz), 3.68 (s, 3H). C{1H} NMR (75
MHz, CDCl3) δ: 26.1, 26.4, 27.6, 32.8, 34.8, 37.8, 39.9, 51.7, 172.5. HRMS (ESI): Calcd for
C11H20NaO2S (M+Na) 239.1076; found 239.1070.
Phenethyl(p-tolyl)sulfane (3u).32 Yield 339 mg (99%). Colorless oil. Chromatography:
hexanes/EtOAc, 20/1. Rf 0.44 (hexanes/EtOAc, 20/1). 1H NMR (300 MHz, CDCl3) δ: 2.42 (s, 3H). 2.99
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(dd, 2H, J = 9.4, 6.3 Hz), 3.21 (dd, 2H, J = 9.0, 6.3 Hz), 7.16–7.42 (m, 9H). C{1H} NMR (75MHz,
CDCl3) δ: 21.1, 35.9, 36.0, 126.5, 128.6, 128.7, 129.9, 130.2, 132.7, 136.2, 140.4.
2-(Phenethylthio)aniline (3v).33 Yield 316 mg (92%). Colorless oil. Chromatography: gradient elution
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hexanes/EtOAc, 12 /1→10/1. Rf 0.2 (hexanes/EtOAc, 10/1). H NMR (300 MHz, CDCl3) δ: 2.89–2.96
(m, 2H), 3.04–3.11 (m, 2H), 4.33 (br s, 2H), 6.74–6.82 (m, 2H), 7.16–7.39 (m, 6H), 7.48 (dd, 1H, J =
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8.1; 1.6 Hz). C{1H} NMR (75MHz, CDCl3) δ: 35.8, 115.0, 117.8, 118.7, 126.4, 128.5, 128.6, 129.7,
135.9, 140.4, 148.3.
(4-Chlorophenyl)(1,1-difluoro-2-phenylethyl)sulfane (3w).13 Yield 418 mg (98%). Colorless crystals.
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Mp 70–71°C. Chromatography: hexanes/CH2Cl2, 25/1. Rf 0.20 (hexanes/CH2Cl2, 25/1). H NMR (300
MHz, CDCl3) δ: 3.49 (t, 2H, J = 14.8 Hz), 7.30–7.45 (m, 7H), 7.55 (d, 2H, J = 8.5 Hz). 13C{1H} NMR
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(75MHz, CDCl3) δ: 45.3 (t, J = 24.1 Hz), 125.5, 128.0, 128.6, 129.4, 130.6, 131.9, 136.4, 137.5. F
NMR (282 MHz, CDCl3) δ: –72.1 (t, J = 14.8 Hz).
(1,1-Difluoro-2-phenylethyl)(perfluorophenyl)sulfane (3x).13 Yield 485 mg (95%). Colorless crystals.
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Mp 51–52°C. Chromatography: hexanes/EtOAc, 20/1. Rf 0.41 (hexanes/EtOAc, 20/1). H NMR (300
MHz, CDCl3) δ: 3.55 (t, 2H, J = 14.7 Hz), 7.35–7.42 (m, 5H). 13C{1H} NMR (75MHz, CDCl3) δ: 45.2
(t, J = 23.1 Hz), 101.3 (t, J = 20.9 Hz), 128.3, 128.4 (t, J = 285.2 Hz), 128.8, 130.6, 137.90 (dm, J =
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256.4 Hz), 143.6 (dm, J = 258.9 Hz), 148.9 (dm, J = 250.4 Hz). 19F NMR (282 MHz, CDCl3) δ: –161.1
(m, 2F), –148.6 (tt, 1F, J = 4.8, 20.6 Hz), –129.8 (dm, J = 20.6 Hz), –70.0 (tt, 2F, J = 14.7; 5.3 Hz).
Cyclohexyl(perfluorophenyl)sulfane (3y).34 Yield 415 mg (98%). Colorless crystals. Mp 54–55 °C.
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Hz). C{1H} NMR (75 MHz, CDCl3) δ: 25.5, 25.9, 33.4, 47.6 (q, J = 1.7 Hz), 137.7 (dm, J = 254.9
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Hz), 141.3 (dm, J = 269.0 Hz), 148.0 (dm, J = 247.5 Hz). F NMR (282 MHz, CDCl3) δ: –161.4 (m,
2F), –152.8 (t, 1F, J = 20.1 Hz), –131.5 (d, 2F, J = 23.6 Hz). HRMS (ESI): Calcd for C12H11F5AgS
(M+Ag) 388.9547; found 388.9547.
S-(4-Phenylbutyl) ethanethioate (3z).35 Yield 306 mg (98%). Colorless oil. Chromatography:
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hexanes/EtOAc,15 /1. Rf 0.36 (hexanes/EtOAc, 15/1). H NMR (300 MHz, CDCl3) δ: 1.59–1.81 (m,
4H), 2.36 (s, 3H), 2.67 (t, 2H, J = 7.1 Hz), 2.94 (t, 2H, J = 6.1 Hz), 7.17–7.26 (m, 3H), 7.27–7.36 (m,
3H). 13C{1H} NMR (75MHz, CDCl3) δ: 29.0, 29.2, 30.6, 30.7, 35.5, 125.9, 128.4, 128.5, 142.1, 195.9.
S-(2-Methyl-4-phenylbutyl) ethanethioate (3za). Yield 394 mg (98%). Colorless oil.
Chromatography: hexanes/EtOAc, 20/1. Rf 0.27 (hexanes/EtOAc, 20/1). 1H NMR (300 MHz, CDCl3) δ:
1.06 (d, 3H, J = 6.6 Hz), 1.48–1.64 (m, 1H), 1.70–1.84 (m, 2H), 2.37 (s, 3H), 2.58–2.78 (m, 2H), 2.86
(dd, 1H, J = 13.6; 7.3 Hz), 3.03 (dd, 1H, J = 13.6; 5.1 Hz), 7.19–7.25 (m, 3H), 7.29–7.36 (m, 2H).
13C{1H} NMR (75 MHz, CDCl3) δ: 19.2, 30.7, 33.0, 33.3, 35.9, 37.8, 125.8, 128.4, 142.3, 195.8. HRMS
(ESI): Calcd for C13H18NaOS (M+Na) 245.0971; found 245.0975.
S-Cyclohexyl ethanethioate (3zb).36 Yield 230 mg (97%). Colorless oil. Chromatography:
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hexanes/EtOAc, 30/1. Rf 0.24 (hexanes/EtOAc, 30/1). H NMR (300 MHz, CDCl3) δ: 1.15–1.50 (m,
5H), 1.51–1.71 (m, 3H), 1.83–1.96 (m, 2H), 2.27 (s, 3H), 3.42–3.55 (m, 1H). C{1H} NMR (75MHz,
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CDCl3) δ: 25.6, 26.0, 30.8, 33.1, 42.5, 195.7.
S-(1-Chloro-3-phenylpropan-2-yl) ethanethioate (3zc). Yield 315 mg (%). Colorless oil.
Chromatography: hexanes/EtOAc, 20/1. Rf 0.28 (hexanes/EtOAc, 20/1). 1H NMR (300 MHz, CDCl3) δ:
2.35 (s, 3H), 3.01 (dd, 1H, J = 13.9; 6.8 Hz), 3.19 (dd, 1H, J = 13.9; 7.3 Hz), 3.63 (dd, 1H, J = 11.2; 6.2
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Hz), 3.71 (dd, 1H, J = 11.2; 3.9 Hz), 4.02–4.12 (m, 1H), 7.26–7.40 (m, 5H). C{1H} NMR (75 MHz,
CDCl3) δ: 30.7, 37.1, 46.6, 127.0, 128.6, 129.3, 137.4, 194.5. HRMS (ESI): Calcd for C11H13ClNaOS
(M+Na) 251.0268; found 251.0264.
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S-(4-Hydroxy-4-phenylbutyl) ethanethioate (3zd). Yield 302 mg (90%). Colorless oil.
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Chromatography: gradient elution hexanes/EtOAc, 4/1→3/1. Rf 0.34 (hexanes/EtOAc, 2/1). H NMR
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(300 MHz, CDCl3) δ: 1.49–1.88 (m, 4H), 2.29 (s, 3H), 2.75 (s, 1H), 2.87 (t, 2H, J = 7.0 Hz), 4.63 (t, 1H,
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J = 5.5 Hz), 7.22–7.37 (m, 5H). C{1H} NMR (75 MHz, CDCl3) δ: 25.898, 28.923, 30.607, 37.911,
73.810, 125.9, 127.5, 128.5, 144.6, 196.2. HRMS (ESI): Calcd for C12H16NaO2S (M+Na) 247.0763;
found 247.0757.
S-[3-(1,3-Dioxoisoindolin-2-yl)propyl]ethanethioate (3ze).37 Yield 359 mg (91%). Yellowish crystals.
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Mp 86–87 °C. H NMR (300 MHz, CDCl3) δ: 1.93 (quint, 2H, J = 7.3 Hz), 1.99 (s, 3H), 2.28 (s, 3H),
2.86 (t, 2H, J = 7.3 Hz), 3.71 (t, 2H, J = 6.9 Hz), 7.68 (dd, 2H, J = 5.5; 3.1 Hz), 7.79 (dd, 2H, J = 5.5;
3.1 Hz). 13C{1H} NMR (75MHz, CDCl3) δ: 26.5, 28.7, 30.7, 37.0, 123.3, 132.1, 134.1, 168.4, 195.3.
Methyl 2-(acetylthio)-3-phenylpropanoate (3zf). Yield 275 mg (77%). Colorless oil.
Chromatography: hexanes/EtOAc, 10/1. Rf 0.25 (hexanes/EtOAc, 10/1). 1H NMR (300 MHz, CDCl3) δ:
2.32 (s, 3H), 3.04 (dd, 1H, J = 13.8; 7.3 Hz), 3.27 (dd, 1H, J = 13.8; 8.1 Hz), 3.67 (s, 3H), 4.47 (dd, 1H,
J = 8.1, 7.3 Hz). 13C{1H} NMR (75 MHz, CDCl3) δ: 30.2, 38.0, 47.1, 52.6, 127.1, 128.5, 129.1, 137.2,
171.4, 193.4. HRMS (ESI): Calcd for C12H14NaO3S (M+Na) 261.0556; found 261.0561.
S-(1,2-Diphenylethyl) ethanethioate (3zg). Yield 346 mg (90%). Colorless oil. Chromatography:
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gradient elution hexanes/EtOAc, 20/1→15/1. Rf 0.37 (hexanes/EtOAc, 15/1). H NMR (300 MHz,
CDCl3) δ: 2.33 (s, 3H), 3.30 (dd, 1H, J = 13.7; 8.4 Hz), 3.33 (dd, 1H, J = 13.7; 7.1 Hz), 4.92 (dd, 1H, J
= 8.4; 7.1 Hz), 7.14 – 7.39 (m, 10H). 13C{1H} NMR (75 MHz, CDCl3) δ: 30.6, 42.9, 49.7, 126.6, 127.5,
128.0, 128.3, 128.6, 129.4, 138.4, 141.0, 194.5. HRMS (ESI): Calcd for C16H16NaOS (M+Na)
279.0814; found 279.0824.
S-(3,3-Dimethylbutyl) benzothioate (3zh). Yield 330 mg (99%). Colorless oil. Chromatography:
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hexanes/EtOAc, 25/1. Rf 0.43 (hexanes/EtOAc, 25/1). H NMR (300 MHz, CDCl3) δ: 1.00 (s, 9H),
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1.54–1.62 (m, 2H), 3.01–3.09 (m, 2H), 7.40–7.47 (m, 2H), 7.55 (tt, 1H, J = 7.4; 1.4 Hz), 7.96–8.01 (m,
2H). 13C{1H} NMR (75 MHz, CDCl3) δ: 25.0, 29.1, 31.1, 43.7, 127.2, 128.6, 133.2, 137.3, 192.0.
HRMS (ESI): Calcd for C13H19OS (M+H) 223.1151; found 223.1160.
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S-(2,3-Dimethylbutan-2-yl) benzothioate (3zi). Yield 257 mg (77%). Colorless oil. Chromatography:
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hexanes/EtOAc, 30/1. Rf 0.37 (hexanes/EtOAc, 30/1). H NMR (300 MHz, CDCl3) δ: 1.05 (d, 6H, J =
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6.9 Hz), 1.60 (s, 6H), 2.33 (sept, 1H, J = 6.9 Hz), 7.39–7.46 (m, 2H), 7.54 (tt, 1H, J = 7.3; 2.1 Hz),
7.93–7.98 (m, 2H). 13C{1H} NMR (75 MHz, CDCl3) δ: 18.1, 24.6, 36.5, 56.5, 127.0, 128.5, 132.8,
138.7, 192.8. HRMS (ESI): Calcd for C13H18NaOS (M+Na) 245.0971; found 245.0979.
S-(3-Chloro-2-methylpropyl) benzothioate (3zj). Yield 280 mg (82%). Colorless oil.
Chromatography: hexanes/EtOAc, 25/1. Rf 0.29 (hexanes/EtOAc, 25/1). 1H NMR (300 MHz, CDCl3) δ:
1.17 (d, 3H, J = 6.8 Hz), 2.14–2.29 (m, 1H), 3.15 (dd, 1H, J = 13.6, 6.4 Hz), 3.21 (dd, 1H, J = 13.6, 6.7
Hz), 3.58 (dd, 1H, J = 11.0, 5.2 Hz), 3.61 (dd, 1H, J = 11.0, 5.5 Hz), 7.43–7.50 (m, 2H), 7.59 (tt, 1H, J
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= 7.4; 1.4 Hz), 7.99–8.02 (m, 2H). C{1H} NMR (75 MHz, CDCl3) δ: 17.4, 32.6, 35.9, 49.5, 127.8,
128.7, 133.5, 136.9, 191.3. HRMS (ESI): Calcd for C11H13ClNaOS (M+Na) 251.0268; found 251.0268.
ASSOCIATED CONTENT
Supporting Information
Stern-Volmer plots, UV-vis measurements, quantum yield determination protocol, copies of NMR
spectra for all compounds (PDF). The Supporting Information is available free of charge on the ACS
Publications website.
AUTHOR INFORMATION
Corresponding Author
* E-mail: adil25@mail.ru
Author Contributions
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The manuscript was written through contributions of all authors. / All authors have given approval to
the final version of the manuscript.
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REFERENCES
7
8
9
(1) (a) Hoyle, C. E.; Bowman, C. N. Thiol-ene click chemistry. Angew. Chem. Int. Ed. 2010, 49,
1540–1573. (b) Sinha, A. K.; Equbal, D. Thiol-Ene Reaction: Synthetic Aspects and Mechanistic
Studies of an Anti-Markovnikov-Selective Hydrothiolation of Olefins. Asian J. Org. Chem. 2019,
8, 32–47. (c) Wimmer, A.; König, B. Photocatalytic formation of carbon-sulfur bonds. Beilstein J.
Org. Chem. 2018, 14, 54–83. (d) Glass, R. S. Sulfur Radicals and Their Application. Top. Curr.
Chem. 2018, 376, 22.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(2) (a) Lowe, A. B. Thiol-Ene “Click” Reactions and Recent Applications in Polymer and Materials
Synthesis. Polym. Chem. 2010, 1, 17–36. (b) Lowe, A. B. Thiol-Ene “Click” Reactions and
Recent Applications in Polymer and Materials Synthesis: a First Update. Polym. Chem. 2014, 5,
4820–4870. (c) Hoyle, C. E.; Lee, T. Y.; Roper, T. Thiol-Enes: Chemistry of the Past with
Promise for the Future. J. Polym. Sci. A 2004, 42, 5301–5338.
(3) (a) Sun, S.; Oliveira, B. L.; Jimenez-Oses, G.; Bernardes, G. J. L. Radical-Mediated Thiol-Ene
Strategy: Photoactivation of Thiol-Containing Drugs in Cancer Cells. Angew. Chem. Int. Ed.
2018, 57, 15832–15835. (b) Dondoni, A.; Marra, A. Recent Applications of Thiol-Ene Coupling
as a Click Process for Glycoconjugation. Chem. Soc. Rev. 2012, 41, 573–586.
(4) For selected recent reports on diverse applications of thiol-ene reaction, see: (a) Sinha, J.;
Fairbanks, B. D.; Song, H. B.; Bowman, C. N. Phosphate-Based Cross-Linked Polymers from
Iodo-ene Photopolymerization: Tuning Surface Wettability through Thiol-ene Chemistry. ACS
Macro Lett. 2019, 8, 213–217. (b) Lee, K.; Lee, J.; Choi, S.; Char, K.; Choi, J. W. Thiol-Ene
Click Reaction for Fine Polarity Tuning of Polymeric Binders in Solution-Processed All-Solid-
State Batteries. ACS Energy Lett. 2019, 4, 94–101. (c) Svejdal, R. R.; Dickinson, E. R.; Sticker,
D.; Kutter, J. P.; Rand, K. D. Thiol-ene Microfluidic Chip for Performing Hydrogen/Deuterium
Exchange of Proteins at Subsecond Time Scales. Anal. Chem. 2019, 91, 1309–1317. (d) Jia, P.;
ACS Paragon Plus Environment

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Ma, Y.; Xia, H.; Zheng, M.; Feng, G.; Hu, L.; Zhang, M.; Zhou, Y. Clean Synthesis of Epoxidized
Tung Oil Derivatives via Phase Transfer Catalyst and Thiol-ene Reaction: A Detailed Study. ACS
Sustainable Chem. Eng. 2018, 6, 13983–13994. (e) Zandi Shafagh, R.; Vastesson, A.; Guo, W.;
van der Wijngaart, W.; Haraldsson, T. E-Beam Nanostructuring and Direct Click
Biofunctionalization of Thiol-Ene Resist. ACS Nano 2018, 12, 9940–9946. (f) Grim, J. C.; Brown,
T. E.; Aguado, B. A.; Chapnick, D. A.; Viert, A. L.; Liu, X.; Anseth, K. S. A Reversible and
Repeatable Thiol–Ene Bioconjugation for Dynamic Patterning of Signaling Proteins in
Hydrogels. ACS Cent. Sci. 2018, 4, 909–916. (g) Sycks, D. G.; Wu, T.; Park, H. S.; Gall, K.
Tough, Stable Spiroacetal Thiol-Ene Resin for 3D Printing. J. Appl. Polym. Sci. 2018, 135, 46259.
(h) Povie, G.; Tran, A.-T.; Bonnaffe, D.; Habegger, J.; Hu, Z.; Le Narvor, C.; Renaud, P.
Repairing the Thiol-Ene Coupling Reaction. Angew. Chem. Int. Ed. 2014, 53, 3894–3898.
(5) Kolb, H. C.; Finn, M. G.; Sharpless, K. B. Click Chemistry: Diverse Chemical Function from a
Few Good Reactions. Angew. Chem. Int. Ed. 2001, 40, 2004–2021.
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
27
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30
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33
34
35
36
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38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(6) For reviews on organic photocatalysis, see: (a) Romero, N. A.; Nicewicz, D. A. Organic
Photoredox Catalysis. Chem. Rev. 2016, 116, 10075–10166. (b) Du, Y.; Pearson, R. M.; Lim, C.-
H.; Sartor, S. M.; Ryan, M. D.; Yang, H.; Damrauer, N. H.; Miyake, G. M. Strongly Reducing,
Visible-Light Organic Photoredox Catalysts as Sustainable Alternatives to Precious Metals. Chem.
Eur. J. 2017, 23, 10962–10968. (c) Joshi-Pangu, A.; Levesque, F.; Roth, H. G.; Oliver, S. F.;
Campeau, L.-C.; Nicewicz, D.; DiRocco, D. A. Acridinium-Based Photocatalysts: A Sustainable
Option in Photoredox Catalysis. J. Org. Chem. 2016, 81, 7244–7249. (d) Hari, D. P.; Konig, B.
Synthetic Applications of eosin Y in Photoredox Catalysis. Chem. Commun. 2014, 50, 6688–
6699.
(7) For reviews on visible light promoted reactions, see: (a) Marzo, L.; Pagire, S. K.; Reiser, O.;
König, B. Visible-Light Photocatalysis: Does It Make a Difference in Organic Synthesis? Angew.
Chem. Int. Ed. 2018, 57, 10034–10072. (b) Staveness, D.; Bosque, I.; Stephenson, C. R. J. Free
Radical Chemistry Enabled by Visible Light-Induced Electron Transfer. Acc. Chem. Res. 2016,
ACS Paragon Plus Environment

Page 19 of 23
The Journal of Organic Chemistry
49, 2295–2306. (c) Ghosh, I.; Marzo, L.; Das, A.; Shaikh, R.; König, B. Visible Light Mediated
Photoredox Catalytic Arylation Reactions. Acc. Chem. Res. 2016, 49, 1566–1577. (d) Strieth-
Kalthoff, F.; James, M. J.; Teders, M.; Pitzer, L.; Glorius, F. Energy Transfer Catalysis Mediated
by Visible Light: Principles, Applications, Directions. Chem. Soc. Rev. 2018, 47, 7190–7202.
1
2
3
4
5
6
7
8
9
(8) (a) Tyson, E. L.; Ament, M. S.; Yoon, T. P. Transition Metal Photoredox Catalysis of Radical
Thiol-Ene Reactions. J. Org. Chem. 2013, 78, 2046–2050. (b) Keylor, M. H.; Park, J. E.;
Wallentin, C.-J.; Stephenson, C. R. J. Photocatalytic Initiation of Thiol-Ene Reactions: Synthesis
of Thiomorpholin-3-ones. Tetrahedron 2014, 70, 4264–4269. (c) Xu, J.; Boyer, C. Visible Light
Photocatalytic Thiol-Ene Reaction: An Elegant Approach for Fast Polymer Postfunctionalization
and Step-Growth Polymerization. Macromolecules 2015, 48, 520–529. (d) Liu, H.; Chung, H.
Visible-Light Induced Thiol-Ene Reaction on Natural Lignin. ACS Sustainable Chem. Eng. 2017,
5, 9160–9168.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(9) (a) Bhat, V. T.; Duspara, P. A.; Seo, S.; Abu Bakar, N. S. B.; Greaney, M. F. Visible light
Promoted Thiol-Ene Reactions Using Titanium Dioxide. Chem. Commun. 2015, 51, 4383–4385.
(b) Fadeyi, O. O.; Mousseau, J. J.; Feng, Y.; Allais, C.; Nuhant, P.; Chen, M. Z.; Pierce, B.;
Robinson, R. Visible-Light-Driven Photocatalytic Initiation of Radical Thiol-Ene Reactions Using
Bismuth Oxide. Org. Lett. 2015, 17, 5756–5759.
(10) (a) Zhao, G.; Kaur, S.; Wang, T. Visible-Light-Mediated Thiol-Ene Reactions through Organic
Photoredox Catalysis. Org. Lett. 2017, 19, 3291–3294. (b) Kaur, S.; Zhao, G.; Busch, E.; Wang,
T. Metal-free photocatalytic thiol-ene/thiol-yne reactions. Org. Biomol. Chem. 2019, 17, 1955–
1961.
(11) (a) Singh, M.; Yadav, A. K.; Yadav, L. D. S.; Singh, R. K. P. Tetrahedron Lett. 2017, 58, 2206–
2208. (b) Limnios, D.; Kokotos, C. G. Photoinitiated Thiol-Ene “Click” Reaction: An
Organocatalytic Alternative. Adv. Synth. Catal. 2017, 359, 323–328. (c) Healy, J.; Rasmussen, T.;
Miller, S.; Booth, I. R.; Conway, S. J. The Photochemical Thiol-Ene Reaction as a Versatile
ACS Paragon Plus Environment

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Page 20 of 23
Method for the Synthesis of Glutathione S-Conjugates Targeting the Bacterial Potassium Efflux
System Kef. Org. Chem. Front. 2016, 3, 439–446.
1
2
3
4
5
6
7
8
9
(12) For light-mediated organocatalyzed thiol-yne reaction applied to aromatic thiols, see: Zalesskiy, S.
S.; Shlapakov, N. S.; Ananikov, V. P. Visible Light Mediated Metal-Free Thiol-Yne Click
Reaction. Chem. Sci. 2016, 7, 6740–6745.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
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34
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36
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38
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40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(13) For Generation of S-Centered Radicals from Disulfides, see: Ashirbaev, S. S.; Levin, V. V.;
Struchkova, M. I.; Dilman, A. D. Addition of Thiols to gem-Difluoroalkenes under
Photoactivation Conditions. Fluorine Notes 2017, 115, 6.
(14) (a) Gentry, E. C.; Knowles, R. R. Synthetic Applications of Proton-Coupled Electron Transfer.
Acc. Chem. Res. 2016, 49, 1546–1556. (b) Weinberg, D. R.; Gagliardi, C. J.; Hull, J. F.; Murphy,
C. F.; Kent, C. A.; Westlake, B. C.; Paul, A.; Ess, D. H.; McCafferty, D. G.; Meyer, T. J. Proton-
Coupled Electron Transfer. Chem. Rev. 2012, 112, 4016–4093.
(15) For various mechanisms of PCET, as well as terminology issues, see: Warren, J. J.; Tronic, T. A.;
Mayer, J. M. Thermochemistry of Proton-Coupled Electron Transfer Reagents and its
Implications. Chem. Rev. 2010, 111, 6961–7001.
(16) For the synthesis and photophysical properties of catalyst 4, see: Mamada, M.; Perez-Bolivar, C.;
Kumaki, D.; Esipenko, N. A.; Tokito, S.; Anzenbacher Jr, P. Benzimidazole Derivatives:
Synthesis, Physical Properties, and n-Type Semiconducting Properties. Chem. Eur. J. 2014, 20,
11835–11846.
(17) In the presence of oxygen, sulfoxides may form as a result of thiol-ene reaction, see: (a) Guerrero-
Corella, A.; Martinez-Gualda, A. M.; Ahmadi, F.; Ming, E.; Fraile, A.; Aleman, J. Thiol-
ene/Oxidation Tandem Reaction under Visible Light Photocatalysis: Synthesis of Alkyl
Sulfoxides. Chem. Commun. 2017, 53, 10463–10466. (b) Cui, H.; Wei, W.; Yang, D.; Zhang, Y.;
Zhao, H.; Wang, L.; Wang, H. Visible-Light-Induced Selective Synthesis of Sulfoxides from
Alkenes and Thiols Using Air as the Oxidant. Green Chem. 2017, 19, 3520–3524.
ACS Paragon Plus Environment

Page 21 of 23
The Journal of Organic Chemistry
(18) Zheng, J.; Cai, J.; Lin, J.-H.; Guo, Y.; Xiao, J.-C. Synthesis and Decarboxylative Wittig Reaction
of Difluoromethylene Phosphobetaine. Chem. Commun. 2013, 49, 7513–7515.
(19) Eisenhart, T. T.; Dempsey, J. L. Photo-induced Proton-Coupled Electron Transfer Reactions of
Acridine Orange: Comprehensive Spectral and Kinetics Analysis. J. Am. Chem. Soc. 2014, 136,
12221–12224.
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
27
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29
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32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(20) For hydrogen bonding between acridine orange and phenols, see: Karmakar, A.; Banerjee, S.;
Singh, B.; Mandal, N. C. Study of Hydrogen Bonding Interaction of Acridine Orange with
Different Acceptor Molecules by Spectroscopic, Theoretical, and Antimicrobial Studies. J. Mol.
Struct. 2019, 1177, 418–429.
(21) For spectroscopic observation of thiol/amine interaction, see: Yamabe, T.; Akagi, K.; Hashimoto,
T.; Nagata, S.; Fukui, K. Hydrogen Bonding Type Charge Transfer Interaction between Thiols
and amines. J. Chem. Soc. Faraday Trans. 1977, 73, 1860–1869.
(22) Cismesia, M. A.; Yoon, T. P. Characterizing Chain Processes in Visible Light Photoredox
Catalysis. Chem. Sci. 2015, 6, 5426–5434.
(23) For kinetic treatment of thiol-ene reaction, see: Sy Piecco, K. W. E.; Aboelenen, A. M.; Pyle, J.
R.; Vicente, J. R.; Gautam, D.; Chen, J. Kinetic Model under Light-Limited Condition for
Photoinitiated Thiol-Ene Coupling Reactions. ACS Omega 2018, 3, 14327–14332.
(24) Sakaguchi, H.; Uetake, Y.; Ohashi, M.; Niwa, T.; Ogoshi, S.; Hosoya, T. Copper-Catalyzed
Regioselective Monodefluoroborylation of Polyfluoroalkenes en Route to Diverse Fluoroalkenes.
J. Am. Chem. Soc. 2017, 139, 12855–12862.
(25) Waser, J.; Nambu, H.; Carreira, E. M. Cobalt-Catalyzed Hydroazidation of Olefins: Convenient
Access to Alkyl Azides. J. Am. Chem. Soc,. 2005, 127, 8294–8295.
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 22 of 23
(26) Ning, X.-S.; Wang, M.-M.; Yao, C.-Z.; Chen, X.-M.; Kang, Y.-B. tert-Butyl Nitrite: Organic
Redox Cocatalyst for Aerobic Aldehyde-Selective Wacker-Tsuji Oxidation. Org. Lett. 2016, 18,
2700–2703.
1
2
3
4
5
6
7
8
9
(27) Kakaei, S.; Chen, N.; Xu, J. Expeditious Synthesis of 1-Substituted Taurines with Diverse
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
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33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Functionalized Side-Chains. Tetrahedron 2013, 69, 302–309.
(28) Podsiadly, R.; Kolinska, J.; Sokolowska, J. Study of Free Radical Polymerisation with Dye
Photoinitiators Containing a Naphthoylenebenzimidazolone Skeleton. Color. Techn. 2008, 124,
79–85.
(29) Bhat, V. T.; Duspara, P. A.; Seo, S.; Abu Bakar, N. S. B.; Greaney, M. F. Visible Light Promoted
Thiol-Ene Reactions using Titanium Dioxide. Chem. Commun. 2015, 51, 4383–4385.
(30) Zhang, X.; Wu, J.; Liu, Y.; Xie, Y.; Liu, C.; Wang, J.; Zhao, G. Facile Synthetic Approaches to 1-
Thiocyclopropanecarboxylates. Phosphorus, Sulfur Relat. Elem. 2017, 192, 799–811.
(31) Schweitzer-Chaput, B.; Boess, E.; Klussmann, M. Acid-Catalyzed Activation of Peroxyketals:
Tunable Radical Initiation at Ambient Temperature and Below. Org. Lett. 2016, 18, 4944–4947.
(32) Chun, S.; Chung, J.; Park, J. E.; Chung, Y. K. Hydrothiolation of Alkenes and Alkynes Catalyzed
by 3,4-Dimethyl-5-vinylthiazolium iodide and Poly(3,4-dimethyl-5-vinylthiazolium) iodide.
ChemCatChem 2016, 8, 2476–2481.
(33) Duan, Z.; Ranjit, S.; Zhang, P.; Liu, X. Synthesis of Aryl Sulfides by Decarboxylative C-S Cross-
Couplings. Chem. Eur. J. 2009, 15, 3666–3669.
(34) Leong, T. S.; Peach, M. E. Some Addition Reactions of Pentafluorothiophenol and
Pentafluorobenzenesulfenyl Chloride. J. Fluorine Chem. 1975, 6, 145–159.
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(35) Kanehara, M.; Oumi, Y.; Sano, T.; Teranishi, T. Syntheses of the Novel Acidic and Basic Ligands
and Superlattice Formation from Gold Nanoparticles through Interparticle Acid-Base Interaction.
Bull. Chem. Soc. Jpn. 2004, 77, 1589–1597.
1
2
3
4
5
6
7
8
9
(36) Kucinski, K.; Hreczycho, G. S-Acetylation of Thiols Mediated by Triflic Acid: A Novel Route to
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Thioesters. Org. Proc. Res. Dev. 2018, 22, 489–493.
(37) Ding, F.; Guy, A. T.; Greimel, P.; Hirabayashi, Y.; Kamiguchi, H.; Ito, Y. Squaryl Group
Modified Phosphoglycolipid Analogs as Potential Modulators of GPR55. Chem. Commun. 2018,
54, 8470–8473.
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