Visible-light-induced decarboxylative sulfonylation of cinnamic acids with sodium sulfinates by using Merrifield resin supported Rose Bengal as a catalyst

Article abstract of DOI:10.1039/c9ob00790c

A visible-light-induced decarboxylative sulfonylation of cinnamic acids with sodium sulfinates for the synthesis of vinyl sulfones was developed. The reaction proceeded smoothly in the presence of Merrifield resin supported Rose Bengal ammonium salt as a

Full text of DOI:10.1039/c9ob00790c

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Takeharu Haino et al.
Solvent-induced emission of organogels based on tris(phenylisoxazolyl)
benzene
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DOI: 10.1039/C9OB00790C
Organic & Biomolecular Chemistry
ARTICLE
Visible-light-induced decarboxylative sulfonylation of cinnamic
acids with sodium sulfinates by using Merrifield resin supported
Rose Bengal as catalyst
Received 00th xxxx 2019
Accepted 00th xxxx 2019
DOI: 10.1039/x0xx00000x
Pinhua Li*a,b and Guan-Wu Wang*a
www.rsc.org/
A visible-light-induced decarboxylative sulfonylation of cinnamic acids with sodium sulfinates for the synthesis of vinyl
sulfones were developed. The reaction underwent smoothly in the presence of Merrifield resin supported Rose Bengal
ammonium salt as a photocatalyst, tert-butyl hydroperoxide (70% in water) as an oxidant in aqueous DMSO solution at
room temperature under green LED (530−535 nm) irradiation in air atmosphere, generating the desired products in good
yields. Notably, the supported catalyst can easily be separated from the reaction mixture by filtration and can be recycled
at least six times without a significant loss of activity.
copper/air catalytic system for the regioselective sulfonation of
alkene in 2014,9 and König also realized the sulfonation of alkene
with sodium sulfonates through visible light photoredox catalysis.10
Despite those established methodologies are efficient, limitations
or drawbacks still remain, such as the use of transition metals,
strong oxidants or harsh reaction conditions. Accordingly, the
development of more practical and alternative route to prepare
vinyl sulfones is still highly desirable.
Introduction
Vinyl sulfones are valuable synthetic intermediates and constitute a
significant component in natural products and in drug discovery.1 In
the past few years, the synthesis of vinyl sulfones has received
much attention and a lot of synthetic routes have been established.
The classic vinyl sulfone preparations are based on the Knoevenagel
condensation and the Horner–Emmons reaction.2 Recently,
decarboxylative sulfonylation of cinnamic acids with sodium
arylsulfonates or aromatic sulfonylhydrazides are one of the most
attractive methods for the preparation of vinyl sulfones (Scheme 1a
and 1b). For the elegant examples, Guo reported the synthesis of
vinyl sulfones by a Cu(II)-catalyzed decarboxylative sulfonylation of
cinnamic acids with sodium sulfonates in 2014,3 and Tan’s group
realized this transformation by a Pd catalyst.4 Moreover, the I2,
PhI(OAc)2 or bases or electrolysis could also promote this
decarboxylative sulfonylation with satisfactory results.5 In addition,
Previous works:
(a) CuO (20 mol%), KI (1.5 eq.), DMSO, 100 o
(b) Pd(OAc)2 (10 mol%), Ag2CO3 (2.0 eq.),
C
O
DMF, 75 o
C
O
S
OH
(c) CuClO4 (20 mol%), TBHP (3.0 eq.),
CH3CN, 110 o
(d) K2CO3 (50 mol%), DMSO, 100 o
(e) I2 (1.0 eq.), K2CO3 (1.0 eq.), H2O, 60o
(f) PhI(OAc)2 (2.0 eq.), DMF, 100 o
(g) I2 (2.0 eq.), TBHP (2.0 eq.), toluene, 90 o
(a)
C
Ar
O
+
C
ArSO2Na
C
C
C
(h) n-Bu4NClO4/AcOH/CH3CN/H2O, Electrolysis
O
Singh
sulfonylation of cinnamic acids with sulfonyl hydrazides in 2015,6
and Cai realized visible-light-induced decarboxylative
sulfonylation of cinnamic acids with sulfonyl hydrazides using eosin
as
photoredox catalyst,7 and Huang demonstrated an
electrochemical decarboxylative sulfonylation of cinnamic acids
with aromatic sulfonylhydrazides in 2017.8 It is note that the
sulfonylation of alkenes with sodium sulfonates or aromatic
sulfonylhydrazides have also been developed. Jiang reported a
developed
an
I2/TBHP-promoted
decarboxylative
O
S
OH
(a) I2 (0.4 eq.), TBHP (2.5 eq.), DBU (1.5 eq.), rt
(b)
(b) t-BuOLi/n-Bu4NBF4/DMSO, Electrolysis
Ar
+
O
(c) Eosin (1 mol%), KI (1.0 eq.), Cs2CO3 (3.0 eq),
hv, rt
a
ArSO2NHNH2
This work:
Y
a
O
O
S
Merrifield resin supported
Rose Bengal ammonium salt (5 mol%)
OH
Ar
(c)
O
+
TBHP (2 eq.), DMSO/H2O (4:1)
green LED, rt
ArSO2Na
Scheme 1. The strategies for Synthesis of vinyl sulfones
As a continuation of our interest in visible-light photochemistry11
and inspired by the recent studies of decarboxylative sulfonylation
of cinnamic acids with sodium sulfonates, we would like to realize
this transformation by visible light photoredox catalysis.
Fortunately, we have achieved this assumed process, the
decarboxylative sulfonylation of cinnamic acids with sodium
a. Department of Chemistry, University of Science and Technology of China, Hefei,
Anhui 230026, P. R. China, E-mail: pphuali@126.com; gwang@ustc.edu.cn.
b. Department of Chemistry, Huaibei Normal University, Huaibei, Anhui 235000, P R
China
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 2019
Org. Chem. Front., 2019, 00, 1-7 | 1
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sulfinates underwent smoothly in the presence of Rose Bengal trace amount of 3a was detected without a photocatVaielywsAtr(tiTclaebOlenlin1e,
DOI: 10.1039/C9OB00790C
sodium salt (5 mol%) as a photocatalyst, tert-butyl hydroperoxide entries 2 and 3). A slightly improved yield of 3a was achieved when
(70% in water) as an oxidant in aqueous DMSO solution at room Table 1 Optimization of the reaction conditionsa
O
temperature under green LED (530−535 nm) irradiation in air
atmosphere. In continuing our efforts to develop economical and
ecofriendly synthetic protocols for organic transformations from
the view of sustainable chemistry,12 a very convenient method for
immobilization of Rose Bengal ammonium salt on Merrifield resin
by overall ion-exchange process has been developed. To our
pleasure, the supported catalyst exhibits high photo-catalytic
activity for the decarboxylative sulfonylation of cinnamic acids with
sodium sulfinates (Scheme 1c). More importantly, the supported
catalyst could be recovered and reused well at least six times
without significant loss of catalytic activity.
The Merrifield resin immobilized Rose Bengal ammonium salt
was easily prepared from the commercially available Merrifield
resin (loading 1.0 mmol/g active Cl, from GL Biochem Shanghai Ltd.)
according to Scheme 2. At first, Merrifield resin reacted with
triethylamine in toluene under reflux condition for 12 h to generate
the benzyltriethylammonium chloride functionalized Merrifield
resin. Then, the resin supported Rose Bengal ammonium salt was
obtained by simply dissolving Rose Bengal sodium salt in the
mixture of DMSO and water (1:1, V/V), and treating it with the
above quaternary ammonium salt functionalized Merrifield resin,
with a loading of 0.025 mmol of RB per gram determined via
spectrophotometric method, and there was no noticeable level of
Rose Bengal leaching in the solution. For a better understanding of
the morphologies of the supported catalysts, SEM photographs
were taken at different synthesis stages. It is clearly visible that the
particles were on the order of micrometer in size, and the relative
smooth surface of the starting polymer changed after
immobilization of the RB catalyst. The recovered catalyst after being
reused five times was also characterized by SEM, and displayed
rather rough surfaces in comparison with the fresh catalyst (Fig. S2,
See supporting information). It means that the mechanical strength
of the Merrifield resin is not good enough, and the surface of the
resin is damaged after long-term stirring.
O
S
Photocatalyst
SO2Na
Oxidant ( 2.0 equiv)
OH
+
O
3 W green LED, rt
Solvent
1a
2a
3a
Yield of 3a
Solvent
Entry Photocatalyst
Oxidant
(%)b
1
2
Eosin Y-Na2
Eosin Y-Na2
–
TBHP
TBHP
TBHP
TBHP
TBHP
DTBP
O2
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO
65
NRc
3
Trace
4
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Rose Bengal
Supported RB
Supported RB
Supported RB
Supported RB
Supported RB
Supported RB
Supported RB
71
5
61d
6
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
CH3CN/H2O
DMF/H2O
41
7
Trace
Trace
Trace
Trace
Trace
Trace
Trace
Trace
76e
8
H2O2
9
K2S2O8
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
10
11
12
13
14
15
16
17
18
19
20
21
THF/H2O
EtOH/H2O
Acetone/ H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
DMSO/H2O
75f
49g, 75h
40i, 70j
50k, 73l
55m, 70n
55o, 72p
aReaction conditions: 1a (0.25 mmol), 2a (0.50 mmol), photocatalyst (5.0
mol%), oxidant (0.50 mmol, 2.0 equiv.), solvent (2.5 mL, VDMSO/VH2O = 4:1) at
room temperature under LED irradiation (3.0 W) in air for 12 h. blsolated
yield. cIn dark. danhydrous DMSO (2.5 mL) was used. eMerrifield resin
immobilized Rose Bengal ammonium salt was added (0.5 g, contain RB
0.0125 mmol). fNitrogen atmosphere. gMerrifield resin immobilized Rose
Bengal ammonium salt was added (0.25 g, contain RB 0.00625 mmol).
hMerrifield resin immobilized Rose Bengal ammonium salt was added (1.0 g,
RB Na2:
Cl
NEt3
Cl
Cl
Cl
Na
Toluene, reflux
NEt3
Cl
contain RB 0.025 mmol). iTBHP (0.25 mmol, 1.0 equiv.) was used. TBHP
j
Cl
COO
(0.75 mmol, 3.0 equiv.) was added. kSodium benzenesulfinate (2a, 0.30
I
I
RB Na2
RB
+
NaCl
l
DMSO/H2O
mmol) was added. Sodium benzenesulfinate (2a, 0.75 mmol) was added.
NEt3
O
O
O
mDMSO/H2O (V/V = 4:1). nDMSO/H2O (V/V = 5:1). oFor 8 h. pFor 16 h. NR = no
reaction.
Merrifield resin supported RB catalyst
I
I
Na
Scheme 2 Preparation of the Merrifield resin supported Rose Bengal
catalyst.
Rose Bengal sodium salt was used as the photocatalyst (Table 1,
entry 4). However, there was only 61% yield of 3a was obtained
when the reaction was performed in anhydrous DMSO (Table 1,
entry 5). The oxidants screening showed that di-tert-butyl peroxide
(DTBP) exhibited inferior reactivity, generating 3a in 41% yields
(Table 1, entry 6), but oxygen, hydrogen peroxide (30% in water)
and potassium persulfate were failed (Table 1, entries 7−9). The
solvent also plays an important role in the reaction and the aqueous
DMSO solution is the best of choice among the tested solvents.
When the model reaction was carried out in the aqueous solution
of CH3CN, DMF, THF, CH3CH2OH and acetone (The volume ratio of
organic solvent to H2O was 4:1), only a trace amount of 3a was
detected (Table 1, entries 10−14). It was pleasing to find that when
Firstly, a model reaction of cinnamic acid (1a, 0.25 mmol) and
sodium benzenesulfinate (2a, 0.50 mmol) was chosen to optimize
the reaction conditions, as shown in Table 1. When the model
reaction was performed in the presence of eosin
Y as a
photocatalyst, tert-butyl hydroperoxide (TBHP, 70% in water) as an
oxidant in aqueous DMSO solution at room temperature under
green LED (530−535 nm) irradiation in air atmosphere, the
corresponding product (E)-(2-(phenylsulfonyl)vinyl)benzene (3a)
was obtained in 65% yield (Table 1, entry 1). In the absence of
visible-light irradiation, no desired product was formed, and only a
2 | Org. Chem. Front., 2019, 00, 1-7
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the Merrifield resin immobilized Rose Bengal ammonium salt was Moreover, m- and o-substituted cinnamic acids with an electron-
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used as the photocatalyst, 76% yield of the desired product 3a was donating or electron-withdrawing group,DsOuIc:h10.a10s39m/C-m9OeBth0y0l7,90mC-
obtained (Table 1, entry 15). Moreover, When the model reaction chloro, o-methyl and o-chloro) on the benzene rings could also be
was conducted under nitrogen atmosphere, the desired product applied to the reaction with 2a and afforded the desired products
was obtained in a comparable yield (Table 1, entry 16). Further (3i−3l) in 63−75% yields, and no obvious steric effect was observed.
investigation on the loading of supported catalyst and oxidant, It is worth mentioning that this strategy could also be used to the
molar ratio of 1a to 2a, volume ratio of DMSO to H2O, as well as reactions of (E)-3-(3,4-dichlorophenyl)acrylic acid and (E)-3-(1-
reaction time was also optimized and presented in Table 1 (entries naphthyl)acrylic acid with 2a or 2b, affording 3m and 3n in 60% and
17−21). After all, the optimized reaction conditions are consisted of 80% yields, respectively. It should be noted that (E)-3-(2-
the supported photocatalyst (5.0 mol%) and TBHP (2.0 equiv) in thienyl)acrylic acid and 3-pyridineacrylic acid were proved to be the
aqueous DMSO solution at room temperature under green LED amenable substrates to afford the desired product 3o and 3p in
irradiation (530–535 nm, 3 W) for 12 h.
62% and 68% yields. Unfortunately, when crotonic acid was used as
substrate, the decarboxylative sulfonylation reaction was failed,
and no any product was obtained.
O
S
O
SO2Na
Supported RB (5 mol%)
OH
+
R1
R
O
Next, the scope of sodium arylsulfinates were also investigated
under optimized reaction conditions, and the results are presented
in Scheme 4. It was observed that a variety of sodium arylsulfinates
are valid substrates for this reaction. The reaction could tolerate a
number of sodium arylsulfinates with an electron-rich substitute
such as Me, t-Bu and OMe at the para-position of the phenyl rings,
affording the desired products 3r−3t in 64−74% yields. Meanwhile,
sodium arylsulfinates with an electron-poor substitute such as Cl, Br
and NO2 at the para-position of the phenyl rings, providing the
corresponding products 3u−3w in 41−71% yields. In addition,
sodium toluene-3-sulphinate was also converted to the
corresponding product 3x in 72% yield. However, the ortho-
substitute sodium benzenesulfinate afforded the products 3y and
3z in lower yields. It should be noted that sodium 3,5-
dichlorophenylsulfinate and sodium 2-naphthalenesulfinate were
also compatible in this reaction, afford the desired product 3aa and
3ab in 52% and 55% yields, respectively. In order to further extend
the scope of the reaction, sodium alkyl sulfinate, such as sodium n-
butylsulfinate, was also employed in this transformation, however,
no desired product 3ac was isolated.
TBHP (2 eq.), DMSO/H2O
Green LED (530-535 nm)
Air, rt, 12 h
R2
R2
3
1
2
, R = CH3 or H
O
S
O
S
O
S
O
O
O
MeO
CH3
Me
3a
3b
3e
3c
,65%
, 76%
, 79%
O
S
O
S
O
S
O
O
O
F
Br
Cl
3d
, 72%
3f
, 70%
, 74%
O
O
S
O
S
Me
S
O
O
O
F3C
Cl
NC
3i
, 75%
3g
, 76%
3h
, 74%
O
S
O
S
O
S
O
O
O
Cl
3l
Me
, 66%
3j
, 72%
3k
, 63%
O
S
O
S
O
S
O
O
O
S
Cl
CH3
CH3
Cl
N
3n
3o
,62%
, 80%
3m
, 61%
O
O
S
O
O
S
SO2Na
S
Supported RB (5 mol%)
OH
+
R
H3C
CH3
O
O
R
TBHP (2 eq.), DMSO/H2O
O
Green LED (530-535 nm)
Air, rt, 12 h
CH3
1a
2
3
3q
,0%
3p
, 68%
Scheme 3. The scope of cinnamic acids [Reaction conditions: 1 (0.25 mmol),
2a or 2b (0.50 mmol), Merrifield resin immobilized Rose Bengal ammonium
salt (0.5 g, contain RB 0.0125 mmol), TBHP (0.50 mmol, 2.0 equiv.),
DMSO/H2O (2.5 mL, V/V = 4:1) at room temperature under green LED
irradiation (530−535 nm, 3 W) for 12 h; isolated yield of the product.]
O
O
O
S
S
S
O
O
O
tBu
OMe
Me
3t
, 64%
3r
3s
, 72%
, 74%
O
S
O
S
O
S
To explore the generality of this decarboxylative sulfonylation
reaction, different substituted cinnamic acids reacted with sodium
benzenesulfinate (2a) or sodium toluene-4-sulphinate (2b) under
the optimized conditions. The results are listed in Scheme 3. In
general, a variety of cinnamic acids were attempted to react with 2a
or 2b, and a broad tolerance of the reaction towards substituents
on the aromatic rings was observed. When cinnamic acids with an
electron-donating group, such as Me, OCH3 on the para-position of
benzene rings reacted smoothly with 2a or 2b to generate the
corresponding products (3b and 3c) in 79% and 65% yields,
respectively. When the cinnamic acids having an electron-
withdrawing group including fluoro, chloro, bromo, trifluoromethyl
and cyano groups on the phenyl rings reacted all with 2a efficiently
to deliver the corresponding products (3d−3h) in 72−76% yields.
O
O
O
NO2
Br
Cl
3w
, 41%
3u
3v
, 71%
, 70%
O
S
O
S
Br
O
S
Me
Me
O
O
O
3x
, 72%
3y
, 54%
3z
, 51%
O
S
O
S
O
S
Cl
Me
O
O
O
Cl
3ac
, 0%
3aa
3ab
, 55%
, 52%
Scheme 4. The scope of sodium sulfinates [Reaction conditions: 1a (0.25
mmol), 2 (0.50 mmol), Merrifield resin immobilized Rose Bengal ammonium
salt (0.5 g, contain RB 0.0125 mmol), TBHP (0.50 mmol, 2.0 equiv.),
This journal is © The Royal Society of Chemistry 2019
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DMSO/H2O (2.5 mL, V/V = 4:1) at room temperature under green LED
irradiation (530−535 nm, 3 W) for 12 h; isolated yield of the product.]
arylsulfinates for the preparation of vinyl sulfones.ViTewheArtriceleaOctniloinne
underwent smoothly in the presence of MDerOrIi:fi1e0ld.10r3e9s/iCn9sOuBp0p0o7r9t0eCd
Rose Bengal ammonium salt as
a photocatalyst, tert-butyl
To further illustrate the utility of the developed methodology, a
gram-scale experiment was conducted. The reaction of cinnamic
acid (1a, 5.0 mmol) and sodium toluene-4-sulphinate (2b, 10.0
mmol) could be performed on 5 mmol scale, providing the desired
product 3a in 62% yield (0.8 g).
hydroperoxide (70% in water) as an oxidant in aqueous DMSO
solution at room temperature under green LED (530−535 nm)
irradiation in air atmosphere, generating the desired products in
good yields. Notably, the supported catalyst can be recycled at least
six times without a significant loss of activity. The supported
catalyst can be easily separated from the reaction mixture by simple
filtration and its further applications in organic synthesis is
underway in our laboratory.
To understand this transformation, a free radical-inhibiting
experiment and analytical survey were conducted. When the model
reaction was carried out in the presence of a radical scavenger
2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO, 2.0 equiv.) under the
standard conditions, the decarboxylative sulfonylation was
completely inhibited, suggesting that a radical process might be
involved in the reaction. Additionally, the electron paramagnetic
resonance (EPR) spectra were recorded using 5,5-dimethyl-
pyrroline-N-oxide (DMPO) for capturing OH•, and the result
indicated that OH• was formed and consumed in the reaction.
Based on the preliminary study and the related reports,13 a possible
mechanism is proposed in Scheme 5. Initially, a tert-butoxyl radical
is produced by a SET from the reaction of excited state of Rose
Bengal* with tert-butyl hydroperoxide (TBHP). Then, a single
electron oxidation of sodium benzenesulfinate (2a) by tert-butoxyl
radical to give the corresponding sulfonyl radical (I) and t-BuONa.
Subsequently, the addition of sulfonyl radical (I) to cinnamic acid
(1a) to afford an important intermediate (II), which reacts with RB+
via SET to afford the desired product 3a along with the release of
CO2 as the sole by-product and the regeneration of RB.
Experimental section
General remarks
1
The H NMR and 13C NMR spectra were recorded on a 400 MHz
Bruker FT-NMR spectrometer (400 MHz and 100 MHz, respectively).
All chemical shifts are given as δ value (ppm) with reference to
tetramethylsilane (TMS) as an internal standard. The peak patterns
are indicated as follows: s, singlet; d, doublet; t, triplet; m,
multiplet; q, quartet. The coupling constants, J, are reported in
Hertz (Hz). High resolution mass spectroscopy data of the product
were collected on an Agilent Technologies 6540 UHD Accurate-
Mass Q-TOF LC/MS (ESI). CHN analysis was performed using a Vario
EL III elementar. Scanning electron micrographs (SEM) were
obtained using a FESEM-SU8220 scanning electron microscope. All
the solvents and commercially available reagents were purchased
from commercial suppliers. Products were purified by flash
chromatography on 200–300 mesh silica gels, SiO2.
tBuO OH
tBuONa
PhSO2Na
RB*
Typical procedure for the decarboxylative sulfonylation of
cinnamic acid with sodium arylsulfinates.
O
OH
Detected
by EPR!
I
( )
PhS
O
RB
RB+
tBuO
Ph
A 10 mL reaction vessel equipped with a magnetic stirrer bar was
charged with cinnamic acid (1a, 0.25 mmol), sodium
benzenesulfinate (2a, 0.50 mmol), Merrifield resin supported Rose
Bengal ammonium salt (5.0 mol%, 0.5 g, contain RB 0.0125 mmol),
TBHP (70% in water, 0.50 mmol, 2.0 equiv.) and DMSO/H2O (2.5 mL,
V/V = 4:1). The reaction vessel was irradiated under green LED
irradiation (530−535 nm, 3 W) at room temperature for 12 h. After
completion of the reaction, the mixture was transferred to the
separating funnel, diluted with ethyl acetate and washed with
water. The aqueous phase was extracted three times with ethyl
acetate and the combined organic layers were dried over
anhydrous Na2SO4, filtered and concentrated in vacuum to yield the
crude product, which was further purified by flash chromatography
(silica gel, petroleum ether/ethyl acetate) to give the desired
product (E)-(2-(phenylsulfonyl)vinyl)benzene (3a) in 76% yield.
O
O
OH
Ph
Ph
OH
CO2
O
S
1a
O
O
II
( )
O
S
Ph
Ph
RB = Supported RB catalyst
3a
Scheme 5. The proposed mechanism
Finally, the viability of recovering and reusing the Merrifield resin
supported Rose Bengal ammonium salt as a photocatalyst for the
visible-light-induced decarboxylative sulfonylation of cinnamic acid
(1a) with sodium toluene-4-sulphinate (2b) was examined. It was
found that the catalyst could be reused at least six times without a
noticeable loss of catalytic activity with minimal levels of Rose
Bengal leaching (See supporting information for detail). The
supported catalyst could be collected and reused by filtration and
the separated catalyst was washed with DMSO, ethyl acetate and
diethyl ether, respectively. After being dried in air, it can be reused
directly without any further treatment.
Characterization data for all products
O
S
O
(E)-(2-(Phenylsulfonyl)vinyl)benzene (3a)[7]: White solid. 1H NMR
(400 MHz, CDCl3) δ: 7.95 (d, J = 8.0 Hz, 2H), 7.68 (d, J = 14.8 Hz, 1H),
7.62−7.59 (m, 1H), 7.55−7.52 (m, 2H), 7.48−7.46 (m, 2H), 7.41−7.35
Conclusions
In conclusion, we have developed
a
visible-light-induced
decarboxylative sulfonylation of cinnamic acids with sodium
4 | Org. Chem. Front., 2019, 00, 1-7
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(m, 3H), 6.88 (d, J = 15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 133.6, 132.5 (q, J = 32.5 Hz), 130.1, 129.4, 128.7, 127.7, 126.0 (q, J =
View Article Online
DOI: 10.1039/C9OB00790C
142.4, 140.6, 133.3, 132.2, 131.1, 129.2, 129.0, 128.5, 127.5, 127.2.
3.7 Hz), 123.6 (q, J = 270.7 Hz).
O
O
S
S
O
O
Me
NC
(E)-4-(2-(Phenylsulfonyl)vinyl)benzonitrile (3h)[14]: White solid. 1H
NMR (400 MHz, CDCl3) δ: 7.96 (d, J = 7.6 Hz, 2H), 7.70−7.65 (m, 4H),
7.61−7.56 (m, 4H), 7.01 (d, J = 7.6 Hz, 1H). 13C NMR (100 MHz,
CDCl3) δ: 139.7, 136.5, 133.8, 132.7, 131.0, 129.5, 128.9, 127.8,
117.9, 114.2.
(E)−1-Methyl-4-(2-(phenylsulfonyl)vinyl)benzene (3b)[7]
:
White
1
solid. H NMR (400 MHz, CDCl3) δ: 7.95−7.93 (m, 2H), 7.66 (d, J =
15.2 Hz, 1H), 7.63−7.58 (m, 1H), 7.55−7.51 (m, 2H), 7.37 (d, J = 8.0
Hz, 2H), 7.18 (d, J = 8.0 Hz, 2H), 6.82 (d, J = 14.8 Hz, 1H), 2.36 (s, 3H).
13C NMR (100 MHz, CDCl3) δ: 142.5, 141.8, 141.0, 133.2, 129.7,
129.6, 129.2, 128.5, 127.5, 126.1, 21.4.
O
Me
S
O
S
O
O
(E)-1-Methyl-3-(2-(phenylsulfonyl)vinyl)benzene (3i)[5f]
:
White
MeO
CH3
(E)-1-methoxy-4-(2-tosylvinyl)benzene (3c)[6]: White solid. 1H NMR
(400 MHz, CDCl3) δ: 7.82 (d, J = 8.0 Hz, 2H), 7.60 (d, J = 15.6 Hz, 1H),
7.42 (d, J = 8.4 Hz, 2H), 7.33 (d, J = 8.4 Hz, 2H), 6.89 (d, J = 8.4 Hz,
2H), 6.70 (d, J = 15.6 Hz, 1H), 3.83 (s, 3H), 2.42 (s, 3H). 13C NMR (100
MHz, CDCl3) δ: 162.0, 144.1, 141.7, 138.2, 130.3, 129.9, 127.5,
125.1, 124.8, 114.5, 55.4, 21.5.
solid. 1H NMR (400 MHz, CDCl3) δ: 7.97−7.94 (m, 2H), 7.67−7.59 (m,
2H), 7.56−7.52 (m, 2H), 7.29−7.25 (m, 3H), 7.23−7.21 (m, 1H), 6.85
(d, J = 15.6 Hz, 1H), 2.34 (s, 3H). 13C NMR (100 MHz, CDCl3) δ: 142.6,
140.8, 138.8, 133.2, 132.3, 132.0, 129.3, 129.1, 128.9, 127.6, 127.0,
125.8, 21.2.
O
Cl
S
O
O
S
O
(E)-1-Chloro-3-(2-(phenylsulfonyl)vinyl)benzene (3j)[7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 7.96−7.94 (m, 2H), 7.65−7.59 (m, 2H),
7.57−7.53 (m, 2H), 7.44 (s, 1H), 7.37−7.29 (m, 3H), 6.90 (d, J = 15.6
Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 140.6, 140.3, 135.0, 134.1,
133.5, 130.9, 130.2, 129.3, 128.9, 128.1, 127.6, 126.7.
F
(E)-1-Fluoro-4-(2-(phenylsulfonyl)vinyl)benzene (3d)[7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 7.96−7.94 (m, 2H), 7.67−7.60 (m, 2H),
7.57−7.53 (m, 2H), 7.50−7.47 (m, 2H), 7.10−7.05 (m, 2H), 6.81 (d, J =
15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 164.3 (d, J = 251.3 Hz),
141.1, 140.7, 133.4, 130.6 (d, J = 8.5 Hz), 129.3, 128.6 (d, J = 3.2 Hz),
127.6, 127.1 (d, J = 2.4 Hz), 116.3 (d, J = 21.7 Hz).
O
S
O
O
Me
S
(E)-1-Methyl-2-(2-(phenylsulfonyl)vinyl)benzene (3k)[7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 7.99−7.94 (m, 3H), 7.64−7.60 (m, 1H),
7.57−7.53 (m, 2H), 7.43 (d, J = 7.6 Hz, 1H), 7.31−7.26 (m, 1H),
7.22−7.16 (m, 2H), 6.79 (d, J = 15.6 Hz, 1H), 2.45 (s, 3H). 13C NMR
(100 MHz, CDCl3) δ: 140.7, 140.1, 138.1, 133.3, 131.2, 131.0, 130.9,
129.3, 128.2, 127.6, 126.8, 126.4, 19.7.
O
Cl
(E)-1-Chloro-4-(2-(phenylsulfonyl)vinyl)benzene (3e)[7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 7.96−7.94 (m, 2H), 7.65−7.61 (m, 2H),
7.57−7.54 (m, 2H), 7.43−7.41 (m, 2H), 7.37−7.35 (m, 2H), 6.85 (d, J =
15.6 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 140.9, 140.5, 137.2,
133.5, 130.9, 129.7, 129.4, 128.0, 127.7.
O
S
O
O
S
Cl
O
(E)-1-Chloro-2-(2-(phenylsulfonyl)vinyl)benzene (3l) [7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 8.07 (d, J = 15.2 Hz, 1H), 7.97 (d, J = 7.6
Hz, 2H), 7.65−7.61 (m, 1H), 7.58−7.54 (m, 2H), 7.50 (dd, J1 = 7.6 Hz,
J2 = 1.6 Hz, 1H), 7.42−7.40 (m, 1H), 7.33 (td, J1 = 15.2 Hz, J2 = 1.6 Hz,
1H), 7.28−7.24 (m, 1H), 6.92 (d, J = 15.6 Hz, 1H). 13C NMR (100 MHz,
CDCl3) δ: 140.3, 138.3, 135.2, 133.5, 131.9, 130.6, 130.3, 130.0,
129.3, 128.2, 127.7, 127.2.
Br
(E)-1-Bromo-4-(2-(phenylsulfonyl)vinyl)benzene (3f)[7]: White solid.
1H NMR (400 MHz, CDCl3) δ: 7.96−7.94 (m, 2H), 7.64−7.60 (m, 2H),
7.57−7.54 (m, 2H), 7.52 (d, J = 8.8 Hz, 2H), 7.34 (d, J = 8.4 Hz, 2H),
6.87 (d, J = 15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 141.0, 140.5,
133.5, 132.3, 131.3, 129.9, 129.4, 128.1, 127.7, 125.6.
O
S
O
O
S
F3C
O
(E)-1-(2-(Phenylsulfonyl)vinyl)-4-(trifluoromethyl)benzene (3g)[7]
:
Cl
Cl
White solid. 1H NMR (400 MHz, CDCl3) δ: 7.98−7.96 (m, 2H), 7.71 (d,
J = 15.2 Hz, 1H), 7.67−7.63 (m, 3H), 7.61−7.55 (m, 4H), 7.00 (d, J =
15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 140.3, 140.1, 135.7,
(E)-1,2-dichloro-4-(2-(phenylsulfonyl)vinyl)benzene (3m)[7]: White
solid. 1H NMR (400 MHz, CDCl3) δ: 7.95 (d, J = 7.6 Hz, 2H),
7.66−7.62 (m, 1H), 7.60−7.58 (m, 4H), 7.46 (d, J = 8.0 Hz, 1H), 7.31
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(d, J = 8.0 Hz, 1H), 6.89 (d, J = 15.6 Hz, 1H). 13C NMR (100 MHz, Hz, 1H), 7.48−7.45 (m, 2H), 7.40−7.36 (m, 3H), 7.01−6.99 (m, 2H),
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13
DOI: 10.1039/C9OB00790C
CDCl3) δ: 140.1, 139.5, 135.2, 133.6, 133.4, 132.3, 131.0, 130.0, 6.86 (d, J = 15.2 Hz, 1H), 3.86 (s, 3H). C NMR (100 MHz, CDCl3) δ:
129.4, 129.3, 127.7, 127.5.
163.5, 141.3, 132.4, 132.1, 130.9, 129.8, 129.0, 128.4, 127.9, 114.5,
55.6.
O
S
O
S
O
CH3
O
(E)-1-(2-tosylvinyl)naphthalene (3n)[15]: White solid. 1H NMR (400
MHz, CDCl3) δ: 8.48 (d, J = 15.2 Hz, 1H), 8.13 (d, J = 8.0 Hz, 1H),
7.89−7.83 (m, 4H), 7.62 (d, J = 7.2 Hz, 1H), 7.59−7.55 (m, 1H),
7.54−7.50 (m, 1H), 7.43−7.39 (m, 1H), 7.34 (d, J = 8.0 Hz, 2H), 6.95
(d, J = 15.2 Hz, 1H), 2.41 (s, 3H). 13C NMR (100 MHz, CDCl3) δ: 144.3,
138.8, 137.6, 133.5, 131.3, 131.2, 129.9 (double), 129.4, 128.7,
127.7, 127.2, 126.4, 125.5, 125.2, 122.9, 21.5.
Br
(E)-1-Bromo-4-(styrylsulfonyl)benzene (3u)[7]: White solid. H NMR
1
(400 MHz, CDCl3) δ: 7.81 (d, J = 8.8 Hz, 2H), 7.71−7.66 (m, 3H),
7.49−7.47 (m, 2H), 7.42−7.37 (m, 3H), 6.85 (d, J = 15.2 Hz, 1H). 13C
NMR (100 MHz, CDCl3) δ: 143.0, 139.8, 132.6, 132.1, 131.4, 129.2,
129.1, 128.6, 126.8.
O
S
O
S
O
Cl
O
1
(E)-1-Chloro-4-(styrylsulfonyl)benzene (3v)[7]: White solid. H NMR
S
CH3
(400 MHz, CDCl3) δ: 7.88 (d, J = 8.8 Hz, 2H), 7.69 (d, J = 15.2 Hz, 1H),
7.52−7.50 (m, 2H), 7.49−7.47 (m, 2H), 7.42−7.37 (m, 3H), 6.85 (d, J =
15.6 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 143.0, 140.0, 139.3,
132.1, 131.3, 129.6, 129.1(double), 128.6, 126.9.
(E)-2-(2-tosylvinyl)thiophene (3o)[5b]: White solid. 1H NMR (400
MHz, CDCl3) δ: 7.81 (d, J = 8.4 Hz, 2H), 7.76 (d, J = 15.2 Hz, 1H), 7.42
(d, J = 5.2 Hz, 1H), 7.34 (d, J = 8.0 Hz, 2H), 7.29 (d, J = 3.6 Hz, 1H),
7.07−7.05 (m, 1H), 6.63 (d, J = 15.2 Hz, 1H), 2.43 (s, 3H). 13C NMR
(100 MHz, CDCl3) δ: 144.3, 137.9, 137.0, 134.6, 132.2, 129.9, 129.8,
128.3, 127.6, 125.8, 21.6.
O
S
O
NO2
O
S
(E)-1-Nitro-4-(styrylsulfonyl)benzene (3w)[7]: Yellow solid. H NMR
1
O
(400 MHz, CDCl3) δ: 8.39 (d, J = 8.8 Hz, 2H), 8.15 (d, J = 9.2 Hz, 2H),
7.78 (d, J = 15.2 Hz, 1H), 7.52−7.50 (m, 2H), 7.48−7.40 (m, 3H), 6.86
(d, J = 15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 150.5, 146.6,
145.0, 131.9, 129.2, 129.0, 128.8, 125.7, 124.5.
N
CH3
(E)-3-(2-tosylvinyl)pyridine (3p)[14]: White solid. 1H NMR (400 MHz,
CDCl3) δ: 8.72−8.63 (m, 2H), 7.84 (br, 3H), 7.66 (d, J = 14.0 Hz, 1H),
7.36 (br, 3H), 6.97 (d, J = 14.0 Hz, 1H), 2.44 (s, 3H). 13C NMR (100
MHz, CDCl3) δ: 151.6, 149.9, 144.7, 138.1, 137.0, 134.7, 130.0,
129.9, 128.3, 127.8, 123.8, 21.5.
O
S
Me
O
O
1
(E)-1-Methyl-3-(styrylsulfonyl)benzene (3x)[16]: Pale solid. H NMR
(400 MHz, CDCl3) δ: 7.76−7.74 (m, 2H), 7.67 (d, J = 15.2 Hz, 1H),
7.48−7.46 (m, 2H), 7.42−7.41 (m, 2H), 7.39−7.37 (m, 3H), 6.88 (d, J =
15.2 Hz, 1H), 2.42 (s, 3H). 13C NMR (100 MHz, CDCl3) δ: 142.1, 140.5,
139.5, 134.1, 132.3, 131.0, 129.1, 128.9, 128.4, 127.8, 127.4, 124.7,
21.2.
S
O
Me
(E)-1-Methyl-4-(styrylsulfonyl)benzene (3r)[7]: White solid. 1H NMR
(400 MHz, CDCl3) δ: 7.83 (d, J = 8.4 Hz, 2H), 7.65 (d, J = 15.2 Hz, 1H),
7.46−7.44 (m, 2H), 7.37−7.36 (m, 3H), 7.34−7.32 (m, 2H), 6.87 (d, J =
15.2 Hz, 1H), 2.41 (s, 3H). 13C NMR (100 MHz, CDCl3) δ: 144.2, 141.7,
137.6, 132.3, 130.9, 129.8, 128.9, 128.4, 127.6, 127.5, 21.4.
O
S
Me
O
O
S
1
(E)-1-methyl-2-(styrylsulfonyl)benzene (3y)[7]: White solid. H NMR
(400 MHz, CDCl3) δ: 8.11 (dd, J1 = 8.0 Hz, J2 = 1.2 Hz, 1H), 7.68 (d, J =
15.6 Hz, 1H), 7.51−7.48 (m, 3H), 7.41−7.39 (m, 4H), 7.30 (d, J = 7.6
Hz, 1H), 6.85 (d, J = 15.6 Hz, 1H), 2.64 (s, 3H). 13C NMR (100 MHz,
CDCl3) δ: 142.8, 138.3, 138.0, 133.6, 132.6, 132.3, 131.2, 129.4,
129.1, 128.5, 126.7, 124.7, 20.3.
O
tBu
(E)-1-(tert-Butyl)-4-(styrylsulfonyl)benzene (3s)[7]: White solid. 1H
NMR (400 MHz, CDCl3) δ: 7.87 (d, J = 8.8 Hz, 2H), 7.67 (d, J = 15.6
Hz, 1H), 7.56−7.54 (m, 2H), 7.48−7.46 (m, 2H), 7.40−7.36 (m, 3H),
6.87 (d, J = 15.6 Hz, 1H), 1.33 (s, 9H). 13C NMR (100 MHz, CDCl3) δ:
157.3, 141.9, 137.6, 132.4, 131.0, 129.0, 128.4, 127.7, 127.5, 126.3,
35.1, 31.0.
O
S
Br
O
O
S
(E)-1-Bromo-2-(styrylsulfonyl)benzene (3z)[17]: Pale solid. 1H NMR
(400 MHz, CDCl3) δ: 8.26 (dd, J1 = 7.6 Hz, J2 = 1.6 Hz, 1H), 7.78 (d, J =
15.6 Hz, 1H), 7.72 (dd, J1 = 7.6 Hz, J2 = 1.2 Hz, 1H), 7.54−7.50 (m,
3H), 7.46−7.43 (m, 1H), 7.42−7.37 (m, 3H), 7.11 (d, J = 15.2 Hz, 1H).
O
OMe
(E)-1-Methoxy-4-(styrylsulfonyl)benzene (3t)[7]: White solid. 1H
NMR (400 MHz, CDCl3) δ: 7.87 (d, J = 8.8 Hz, 2H), 7.63 (d, J = 15.2
6 | Org. Chem. Front., 2019, 00, 1-7
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13C NMR (100 MHz, CDCl3) δ: 145.3, 139.8, 135.4, 134.4, 132.3,
131.3, 131.0, 129.0, 128.6, 128.0, 125.0, 120.9.
1073; (b) D. A. R. Happer, B. E. Steenson, Synthesis, 1980, 806;
(c) I. C. Popoff, J. L. Dever, G. R. LeaderD, OJ.I:O1r0g.1.0C3h9e/Cm9.O, 1B9060979, 03C4,
1128.
View Article Online
O
3. Q. Jiang, B. Xu, A. Zhao, Y. Zhao, Y. Li, N. He and C. Guo, J. Org.
Chem., 2014, 79, 7372.
S
Cl
O
4. R. Guo, Q. Gui, D. Wang and Z. Tan, Catal. Lett., 2014, 144, 1377.
5. (a) Y. Xu, X. Tang, W. Hu, W. Wu and H. Jiang, Green Chem.,
2014, 16, 3720; (b) B. V. Rokade and K. R. Prabhu, J. Org. Chem.,
2014, 79, 8110; (c) J. Gao, J. Lai and G. Yuan, RSC Adv., 2015, 5,
66723; (d) P. Katrun, S. Hlekhlai, J. Meesin, M. Pohmakotr, V.
Reutrakul, T. Jaipetch, D. Soorukram and C. Kuhakarn, Org.
Biomol. Chem., 2015, 13, 4785; (e) J. Chen, J. Mao, Y. Zheng, D.
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5059; (f) P. Qian, M. Bi, J. Su, Z. Zha and Z. Wang, J. Org. Chem.,
2016, 81, 4876.
Cl
(E)-1,3-Dichloro-5-(styrylsulfonyl)benzene (3aa): White solid. 1H
NMR (400 MHz, CDCl3) δ: 7.82 (d, J = 2.0 Hz, 2H), 7.72 (d, J = 15.2
Hz, 1H), 7.57−7.56 (m, 1H), 7.52−7.50 (m, 2H), 7.45−7.39 (m, 3H),
6.84 (d, J = 15.2 Hz, 1H). 13C NMR (100 MHz, CDCl3) δ: 144.4, 143.8,
136.3, 133.3, 131.9, 131.7, 129.2, 128.8, 126.0, 125.9. HRMS (EI):
Calcd. for C14H10Cl2NaO2S: 334.9671, found: 334.9671.
O
S
O
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(E)-2-(Styrylsulfonyl)naphthalene (3ab)[7]: White solid. 1H NMR
(400 MHz, CDCl3) δ: 8.55 (d, J = 1.2 Hz, 1H), 8.00−7.97 (m, 2H),
7.92−7.87 (m, 2H), 7.74 (d, J = 15.2 Hz, 1H), 7.67−7.59 (m, 2H),
7.50−7.47 (m, 2H), 7.41−7.36 (m, 3H), 6.92 (d, J = 15.2 Hz, 1H). 13
C
NMR (100 MHz, CDCl3) δ: 142.5, 137.5, 135.1, 132.4, 132.3, 131.2,
129.6, 129.4, 129.2 (double), 129.1, 128.6, 127.9, 127.6, 127.4,
122.5.
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2015, 357, 2050.
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51, 7520; (b) X. Zhu, M.-Y. Han, P. Li and L. Wang, Org. Chem.
Front., 2017, 4, 1640; (c) Y. Zhang, W. Chen, X. Jia, L. Wang and
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Conflicts of interest
There are no conflicts to declare.
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Acknowledgements
We gratefully acknowledge the National Natural Science
Foundation of China (21772062), the Young Talent Key Project of
Anhui Province (170808J02) and the Scientific Research Project of
Anhui Provincial Education Department (KJ2015TD002) for financial
support.
Notes and reference
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T. Pathak and B. Ganguly, Org. Lett., 2014, 16, 2100; (e) J. K.
Laha, Chem. Nat. Compd., 2010, 46, 254; (f) R. Ettari, E. Nizi, M.
E. D. Francesco, M.-A. Dude, G. Pradel, R. Vičík, T. Schirmeister,
N. Micale, S. Grasso and M. Zappalà, J. Med. Chem., 2008, 51,
988; (g) M. V. R. Reddy, P. Venkatapuram, M. R. Mallireddigari,
V. R. Pallela, S. C. Cosenza, K. A. Robell, B. Akula, B. S. Hoffman
and E. P. Reddy, J. Med. Chem., 2011, 54, 6254; (h) X. Ning, Y.
Guo, X. Wang, X. Ma, C. Tian, X. Shi, R. Zhu, C. Cheng, Y. Du, Z.
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