Metal-free sulfonylation of quinones with sulfonyl hydrazides in water: Facile access to mono-sulfonylated hydroquinones

Article abstract of DOI:10.1016/j.tet.2017.03.066

This paper describes a simple and practical protocol for the direct synthesis of monosulfonylated hydroquinones through a transition-metal-free cross-coupling between quinones and sulfonyl hydrazides in water. The procedure tolerates a variety of quinones

Full text of DOI:10.1016/j.tet.2017.03.066

Accepted Manuscript
Metal-free sulfonylation of quinones with sulfonyl hydrazides in water: Facile access
to mono-sulfonylated hydroquinones
Bin Li, Yaqin Li, Linqian Yu, Xiaoyu Wu, Wanguo Wei
PII:
S0040-4020(17)30317-4
10.1016/j.tet.2017.03.066
TET 28572
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 6 February 2017
Revised Date: 21 March 2017
Accepted Date: 23 March 2017
Please cite this article as: Li B, Li Y, Yu L, Wu X, Wei W, Metal-free sulfonylation of quinones with
sulfonyl hydrazides in water: Facile access to mono-sulfonylated hydroquinones, Tetrahedron (2017),
doi: 10.1016/j.tet.2017.03.066.
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Metal-Free Sulfonylation of Quinones with
Sulfonyl Hydrazides in Water: Facile Access
to Mono-Sulfonylated Hydroquinones
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Bin Li, Yaqin Li, Linqian Yu, Xiaoyu Wu*, and Wanguo Wei*

1
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Tetrahedron
journal homepage: www.elsevier.com
Metal-Free Sulfonylation of Quinones with Sulfonyl Hydrazides in Water: Facile
Access to Mono-Sulfonylated Hydroquinones
Bin Li a, Yaqin Li a, Linqian Yu b, Xiaoyu Wu a, , and Wanguo Wei b,
aDepartment of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
bShanghai Advanced Research Institute, Chinese Academy of Sciences, 99 Haike Road, Shanghai 201210, China
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
This paper describes a simple and practical protocol for the direct synthesis of monosulfonylated
hydroquinones through a transition-metal-free cross-coupling between quinones and sulfonyl
hydrazides in water. The procedure tolerates a variety of quinones and widely available sulfonyl
hydrazides.
Available online
2017 Elsevier Ltd. All rights reserved
.
Keywords:
Metal-free
Quinone
Sulfonylation
Phenol
Hydroquinone
1. Introduction
Benzoquinone and hydroquinone derivatives are important
structural motifs that are widely used in many fields, such as
color chemistry, antioxidant, dyes, cosmetics, pesticides,
photography, electrochemicals, and medicinal chemistry.1 In
addition, the sulfonyl derivatives of hydroquinones are a
component of molecular framework of many biologically active
compounds and possess a variety of biological properties,
including antitumor,2 HIV transcriptase inhibition,3 and
immunemodulation properties.4 For example, 2-tosylbenzene-1,4-
diol and 2-tosylnaphthalene-1,4-diol are potent inhibitors of β-
Ketoacyl-ACP-synthase III (FabH),5 a key condensing enzyme
for bacterial fatty acid biosynthesis. Alkylmercapto-2,3-
dimethoxy-1,4-benzoquinones are inhibitors of coenzyme Q
systems.6 Aminopyridine-based sulfones are potent c-jun-N-
terminal kinase-1 (JNK-1) inhibitors.7 Chalcone derivatives have
marked cytotoxic activity,8 and pyridine-based derivatives are
Figure 1. Selected biologically active sulfone-containing hydroquinones.
As a consequence, extensive efforts have been devoted to the
discovery of efficient and environmentally friendly methods for
the synthesis of sulfonylated quinones or hydroquinones. The
most common route involves the conjugate addition of alkyl- or
arylsulfinic acids/salts to benzoquinones under acidic or basic
conditions,11 or in ionic liquid solvents.12 Alternative routes
involve the conjugate addition of thiols to quinones to provide
alkyl/aryl thioquinones, followed by oxidation.13 Recently, wang
et al. reported the transition metal-catalyzed C-H sulfonylation of
quinones with sulfonyl chloride to produce sulfonyl quinones.14
With the rapidly development of new methodologies for direct C-
H functionalization in recent years, direct sulfonylation of C-H
bond represents remarkable approach for efficient sulfone
synthesis,15 which avoids the use of awful smell of thioalcohols
selective thyroid receptor
β
agonists.9 Furthermore, 4-(3-
aryloxyaryl)quinoline sulfones are also potent liver X receptor
agonists.10
———
Corresponding authors. e-mail: wuxy@shu.edu.cn (X. Wu), weiwg@sari.ac.cn (W. Wei).

2
Tetrahedron
and thiophenols. Meanwhile, various sulfonylation reagents,
14
H2O
50 oC
6
24
ACCEPTED MANUSCRIPT KOAc
such as sulfonyl hydrazides,16 N-(thiophenyl) succinimide,17
sodium sulfonates,18 sodium sulfinates19 and arylsulfonyl
chlorides20 have been shown to be effective to C-sulfonylation.
As part of our ongoing efforts to explore sulfonyl hydrazides as
cost-effective and easy to handle agents to introduce C-S bond,
we report herein a direct synthesis of mono-sulfonyl substituted
hydroquinones through a metal-free sulfonylation of quinones
with sulfonyl hydrazides in water.
a
Reaction conditions: benzoquinone 1a (0.5 mmol, 1.0 equiv.), p-
tolylsulfonyl hydrazide 2a (0.75 mmol, 1.5 equiv.), additive (1.0 equiv.),
solvent (5.0 mL), 50 oC, 6 h. b Isolated yields.
With the optimized reaction conditions in hand, we began to
investigate the scope and limitations of this reaction. As shown in
Table 2, a variety of 1,4-benzoquinones, bearing either electron-
donating groups (R1 = OMe), electron neutral (R1 = H, Me) or
weak electron-withdrawing groups (R1 = Cl) on the quinone ring,
reacted smoothly with various sulfonyl hydrazides (RSO2NHNH2)
affording the corresponding mono-sulfonylated hydroquinones
3a-p in moderate to excellent yields (Table 2). In contrast,
sterically enhanced alkyl substituents such as 2,6-di-tert-butyl
group on the benzoquinone ring affected the reactivity
remarkably, and 2,6-di-tert-butylbenzoquinone 1c did not react
with any of the sulfonyl hydrazides investigated here. Quinone
bearing a strong electron-withdrawing group (-CF3) were not
applicable, and no reaction occurred.
2. Results/Discussion
Our initial investigation began with 1,4-benzoquinone (1a)
with p-toluenesulfonyl hydrazide (2a) as the standard substrates
to screen conditions for the metal-free cross-coupling under
ambient atmosphere (Table 1). To our delight, the model reaction
proceeded smoothly, and gave full conversion within 12 h at
room temperature in variety of common organic solvents.
However, solvent evaluation revealed that use of organic solvents
including toluene, methanol, tetrahydrofuran, acetonitrile, 1,2-
dichloroethane and 1,4-dioxane gave moderate results, with
yields ranging from 32% to 54% (Table 1, entries 1-6).
Intriguingly, H2O was found to be superior to common organic
solvents in this transformation, and the reaction proceeded
smoothly and completed in 12 hours at room temperature,
providing 2-tosylbenzene-1,4-diol (3a) in 64% yield (entry 7).
The structure of 3a was unambiguously determined by single
crystal X-ray crystallographic analyses (see the Supporting
Information for details). Moreover, when the reaction
Table 2. Scope of benzoquinones and sulfonyl hydrazides
O
OH
R1
HO
O
O
S
H2O
R1
S
R2
+
R2
NH
NH2
50 oC, 6 h
O
O
O
1a-e
2a-g, h
3a-p
Entry
Quinone 1
Hydrazide 2
Product
3, Yield
o
temperature was raised up to 50 C or even higher, the reaction
proceeded faster with slightly improved yield (entries 8-9, 68%).
Additives such as Li2CO3 gave comparable result (entry 10, 60%).
Further screening of various organic and inorganic additives such
as Et3N, and KOAc was found to show no improvement in the
reaction rate and isolated yield (entries 11-14, 24-40%).
Table 1. Screening of conditions
Entrya
Solvent
Toluene
MeOH
THF
Additive Temp
Time (h)
Yield (%)b
1
None
None
None
None
None
None
None
None
None
Li2CO3
Et3N
rt
12
12
12
12
12
12
12
6
40
54
42
38
36
32
64
68
68
60
32
40
38
2
rt
3
rt
4
CH3CN
DCE
rt
5
rt
6
Dioxane
H2O
rt
7
rt
8
H2O
50 oC
80 oC
50 oC
50 oC
50 oC
50 oC
9
H2O
6
10
11
12
13
H2O
6
H2O
6
H2O
Na2CO3
PivOH
6
H2O
6

3
a
rings, providing the corresponding 2-arylsulfonyl-naphthalene-
Reaction conditions: 1,4-benzoquinone 1 (0.5AmCmoCl, E1.P0 TeqEuiDv.), MANUSCRIPT
o
b
1,4-diol 5a-g in excellent yields. Moreover, various alkylsulfonyl
hydrazides, such as methyl or n-butyl sulfonyl hydrazides were
also tolerable, providing the corresponding 2-alkylsulfonyl-
naphthalene-1,4-diols 5h-i (Table 3, entries 8-9) in high yields.
sulfonyl hydrazide 2 (0.75 mmol, 1.5 equiv.), H2O (5.0 mL), 50 C, 6 h.
Isolated yields.
Table 3. Scope of 1,4-naphthoquinone 4 and sulfonyl
hydrazides
Finally, we showed that 2-tosylnaphthalene-1,4-diol 5a, a
PfFabH inhibitor, generated from naphthalene-1,4-dione 4, could
be oxidized with MnO2 in CH3CN at room temperature to
provide 2-tosylnaphthalene-1,4-dione 6 in excellent yield. Weak
oxidants such as H2O2 or TBHP were unable to oxidize phenol 5a
to quinone owing to the strong withdrawing sulfonyl group.
While C-H sulfonylation of naphthalene-1,4-dione 4 with n-
Entrya
Hydrazide 2
Product
5, Yieldb
butylsulfonyl
hydrazide
in
water
provided
2-
(butylsulfonyl)naphthalene-1,4-diol 5i in excellent yield. The two
hydroxyl groups in 5i could be alkylated selectively with allyl
bromide in the presence of K2CO3 in acetone to give 7, and
further alkylation of the remaining 1-phenol group with methyl
iodide, giving hydroquinone ether 8 in good yield (Scheme 1).
O
OH
O
S
S
NH2
Me
N
H
1
O
5a, 82%
O
2a
Me
OH
OH
O
S
O
S
NH2
N
H
5b, 96%
5c, 87%
2
3
O
O
O
OH
O
2b
Me
Me
b
c
a
O
S
O
S
OH
OH
O
S
O
S
O
OH
O
O
O
OMe
NH2
N
H
4
5a
6
O
O
2d
d
MeO
OH
OH
OH
OR3
OR4
O
S
O
S
e
f
NH2
Cl
O
S
O
S
N
H
4
5
6
O
O
5d, 95%
5e, 90%
5f, 89%
Me
Me
2g
Cl
F3C
O2N
OH
O
O
OH
OH
5i
7:
R
3 = Ally, R2 = H
8: R4 = Ally, R2 = Me
O
S
O
S
NH2
CF3
N
H
Scheme 1. Reagents and conditions: a) p-TsNHNH2, H2O, 50 oC, 6 h, 82%; b)
MnO2, CH3CN, rt, 80%; c) NaBH4, CH3OH, rt; d) n-C4H9SO2NHNH2, H2O, rt,
55%; e) Allyl bromide, K2CO3, rt, 60%; f) MeI, K2CO3, acetone, rt, 84%.
O
O
2i
OH
OH
O
S
O
S
Based on the results described above and previous reports,21
a
NH2
NO2
N
H
O
O
plausible mechanism was proposed (Scheme 2). Initially,
sulfonyl hydrazide 2 is converted to a sulfinyl anion 9, which can
resonate with the sulfur-centered anion 10 in the presence of
water, with the generation of hydronium ions and the release of
nitrogen. Then, conjugate addition of sulfinyl sulfur to 1,4-
benzoquinone 10 provided the sulfonylated hydroquinones 3.
Water may activate the sulfinyl as wells as 1,4-benzoquinone
through hydrogen bond formation and thereby promotes the
Michael addition.
2e
OH
OH
O
S
O
S
NH2
N
H
7
8
5g, 94%
5h, 75%
O
Br
O
Br
2c
OH
OH
O
S
O
S
Me
NH2
NH
O
Me
O
2f
OH
OH
O
S
O
S
Me
NH2
NH
9
5i,
55%
Me
O
O
2h
OH
a
Reaction conditions: 1,4-naphthoquinone 4 (0.5 mmol, 1.0 equiv.),
o
b
sulfonyl hydrazide 2 (0.75 mmol, 1.5 equiv.), H2O (5.0 mL), 50 C, 6 h.
Isolated yields.
Given that 1,4-naphthoquinols are important derivatives for
various applications,4 we further expanded our optimized method
in this aspect. We applied a variety of substituted sulfonyl
hydrazides as sulfonylation reagents in this reaction. Remarkably,
the reaction proceeded smoothly under the standard reaction
conditions, leading to the desired products in good to excellent
yields (Table 3, 5a-i, 55-96%). The reaction tolerates a variety of
aryl sulfonyl hydrazides, including these bearing electron-rich
(Table 3, entry 1, entry 3), electron-neutral (Table 3, entry 2), or
electron-withdrawing (Table 3, entries 4-7) groups on the aryl
Scheme 2. Plausible reaction mechanism.
3. Conclusions
In conclusion, we have reported a very simple and practical
protocol for C-H sulfonylation of quinones or benzoquinones

4
Tetrahedron
ACCEPTED MANUSCRIPT
with hydrazides to provide mono-sulfonylated hydroquinones
= 163.65, 149.90, 148.40, 132.76, 129.96, 126.51, 122.46,
in moderate to excellent yields. The reaction tolerates a variety of
quinones and readily available sulfonyl hydrazides. Significantly,
this method provides a new, simple and direct approach to access
structurally diverse mono-sulfonylate hydroquinones possessing
probable pharmaceutical properties, in an environmentally-
friendly manner.
118.15, 113.74, 113.62, 54.83 ppm. IR (KBr): 3265, 2433, 1593,
1496, 1367, 1285, 1268, 1139, 1091, 1029, 819, 718, 587 cm-1.
HRMS (ESI): calcd for C13H12NaO5S [M + Na]+ 303.0303; found
303.0300.
4.2.5. 2-((4-Nitrophenyl)sulfonyl)benzene-1,4-diol (3e). White
o
1
solid (112 mg, 82% yield), mp 212-213 C. H NMR (500 MHz,
CD3OD): δ = 8.38 (d, J = 8.7 Hz, 2H), 8.19 (d, J = 8.7 Hz, 2H),
7.43 (d, J = 2.8 Hz, 1H), 6.98 (dd, J = 8.7, 2.8 Hz, 1H), 6.75 (d, J
= 8.8 Hz, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ = 150.42,
150.10, 148.84, 147.01, 129.31, 124.97, 123.53, 123.51, 118.16,
114.02 ppm. IR (KBr): 3258, 3111, 2427, 1526, 1351, 1292,
1145, 741, 617 cm-1. HRMS (ESI): calcd for C12H10NO6S [M +
H]+ 296.0229; found 296.0224.
4. Experimental Section
4.1. General Methods
All reagents were purchased from commercial suppliers and
used without further purification. Flash chromatography was
carried out with silica gel (200-300 mesh). Analytical TLC was
performed with silica gel GF254 plates, and the products were
visualized by UV detection. 1H and 13C NMR (500 MHz and 126
MHz, respectively) spectra were recorded in CDCl3 or CD3OD.
Chemical shifts (δ) are reported in ppm using TMS as internal
standard, and spin-spin coupling constants (J) are given in Hz. IR
spectra were recorded on a Nicolet iS5 infrared spectrometer.
HRMS spectra were recorded on Agilent Techologies 6230 TOF
LC/MS spectrometer.
4.2.6. 2-(Methylsulfonyl)benzene-1,4-diol (3f). White solid (42
mg, 45% yield), mp 213-214 oC. 1H NMR (500 MHz, CD3OD): δ
= 7.23 (d, J = 3.0 Hz, 1H), 6.97 (dd, J = 8.8, 3.0 Hz, 1H), 6.87 (d,
J = 8.8 Hz, 1H), 3.24 (s, 3H) ppm. 13C NMR (126 MHz,
CD3OD): δ = 149.90, 148.48, 125.84, 122.43, 117.86, 113.52,
41.53 ppm. IR (KBr): 3354, 1499, 1448, 1286, 1140, 965, 828,
761, 502 cm-1. HRMS (ESI): calcd for C7H8NaO4S [M + Na]+
211.0041; found 211.0035.
4.2. General procedure for the reaction of 1,4-quinones with
sulfonyl hydrazides
4.2.7. 2,5-Dimethyl-3-(phenylsulfonyl)benzene-1,4-diol (3g).
o
1
White solid (78 mg, 56% yield), mp 159-160 C. H NMR (500
MHz, CD3OD): δ = 7.85 (dd, J = 5.3, 3.4 Hz, 2H), 7.70-7.65 (m,
1H), 7.59 (dd, J = 10.6, 4.9 Hz, 2H), 6.94 (s, 1H), 2.21 (s, 3H),
2.11 (s, 3H) ppm. 13C NMR (126 MHz, CD3OD): δ = 149.28,
147.89, 142.30, 133.36, 129.03, 126.11, 125.76, 123.97, 120.69,
119.86, 14.93, 11.33 ppm. IR (KBr): 3450, 3286, 2556, 2450,
1472, 1279, 1249, 1132, 1074, 1013, 716, 603 cm-1. HRMS
(ESI): calcd for C14H14NaO4S [M + Na]+ 301.0510; found
301.0505.
A mixture of 1,4-quinone 1 (0.50 mmol, 1.0 equiv.), sulfonyl
hydrazide 2 (0.75 mmol, 1.5 equiv.) in H2O (5.0 mL) was stirred
at 50 oC for 6 h. Upon the completion of the reaction, the mixture
was extracted with ethyl acetate (3 x 20 mL). The combined
organic layers were dried over Na2SO4, filtered, and evaporated
under reduced pressure to give crude product, which was purified
by flash column chromatography on silica gel with ethyl acetate
and petroleum ether as eluents to give the corresponding product
3a-p and 5a-i.
4.2.8. 3-((4-Methoxyphenyl)sulfonyl)-2,5-dimethylbenzene-1,4-
4.2.1. 2-Tosylbenzene-1,4-diol (3a). White solid (89 mg, 68%
o
1
o
1
diol (3h). White solid (86 mg, 52% yield), mp 134-135 C. H
NMR (500 MHz, CD3OD): δ = 7.76 (d, J = 8.7 Hz, 2H), 7.01 (d,
J = 8.7 Hz, 2H), 6.92 (s, 1H), 3.81 (s, 3H), 2.19 (s, 3H), 2.14 (s,
3H) ppm. 13C NMR (126 MHz, CD3OD): δ = 163.76, 148.96,
147.77, 133.49, 128.52, 125.71, 123.73, 120.66, 120.62, 114.11,
54.94, 15.04, 11.38 ppm. IR (KBr): 3480, 3272, 1593, 1498,
1417, 1260, 1181, 1119, 1072, 843, 670, 595 cm-1. HRMS (ESI):
calcd for C15H16NaO5S [M + Na]+ 331.0616; found 331.0612.
yield), mp 209-210 C. H NMR (500 MHz, CD3OD): δ = 7.83
(d, J = 6.8 Hz, 2H), 7.40-7.29 (m, 3H), 6.99-6.85 (m, 1H), 6.74
(dd, J = 8.8, 1.6 Hz, 1H), 2.40 (s, 3H) pm. 13C NMR (126 MHz,
MeOD): δ = 149.94, 148.57, 144.18, 138.52, 129.00, 127.68,
126.08, 122.68, 118.19, 113.86, 20.11 ppm. IR (KBr): 3287,
1506, 1465, 1284, 1140, 1089，818, 714 cm-1.
4.2.2. 2-(Phenylsulfonyl)benzene-1,4-diol (3b). White solid (81
mg, 65% yield), mp 197-18 oC. 1H NMR (500 MHz, CD3OD) δ =
7.96 (d, J = 7.9 Hz, 2H), 7.61 (t, J = 7.4 Hz, 1H), 7.53 (t, J = 7.6
Hz, 2H), 7.40 (d, J = 2.8 Hz, 1H), 6.95 (dd, J = 8.8, 2.9 Hz, 1H),
6.76 (d, J = 8.8 Hz, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ
= 149.95, 148.67, 141.41, 132.96, 128.48, 127.63, 125.83,
122.91, 118.24, 113.97 ppm. IR (KBr): 3273, 1510, 1370, 1299,
1221, 1142, 1094, 1011, 833, 757, 624 cm-1.
4.2.9. 3-((4-Chlorophenyl)sulfonyl)-2,5-dimethylbenzene-1,4-diol
o
1
(3i). White solid (64 mg, 41% yield), mp 169-171 C. H NMR
(500 MHz, CD3OD): δ = 7.86-7.81 (m, 2H), 7.64-7.57 (m, 2H),
6.95 (s, 1H), 2.20 (s, 3H), 2.14 (s, 3H) ppm. 13C NMR (126 MHz,
CD3OD): δ = 149.21, 148.01, 141.02, 139.63, 129.29, 127.91,
125.92, 124.17, 120.66, 119.69, 14.94, 11.38 ppm. IR (KBr):
3486, 3304, 2581, 2465, 1583, 1474, 1254, 1133, 1092, 1012,
756, 630 cm-1. HRMS (ESI): calcd for C14H13ClNaO4S [M + Na]+
335.0121; found 335.0115.
4.2.3. 2-((2-Bromphenyl)sulfonyl)benzene-1,4-diol (3c). White
o
1
solid (98 mg, 60% yield), mp 219-220 C. H NMR (500 MHz,
CD3OD): δ = 8.36 (d, J = 7.9 Hz, 1H), 7.71 (d, J = 7.9 Hz, 1H),
7.60 (t, J = 7.6 Hz, 1H), 7.50 (dd, J = 14.0, 6.9 Hz, 1H), 7.46 (d,
J = 2.9 Hz, 1H), 6.97 (dd, J = 8.8, 2.9 Hz, 1H), 6.72 (d, J = 8.8
Hz, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ = 149.53, 148.76,
140.21, 134.81, 134.20, 132.18, 127.13, 124.38, 123.06, 119.94,
117.77, 115.83 ppm. IR (KBr): 3305, 2923, 2853, 1502, 1358,
1311, 1150, 1022, 823, 743, 602, 558 cm-1. HRMS (ESI): calcd
for C12H9BrNaO4S [M + Na]+ 350.9303; found 350.9296.
4.2.10. 2,3-Dimethoxy-5-tosylbenzene-1,4-diol (3k). White solid
(92 mg, 57% yield), mp 163-165 oC. 1H NMR (500 MHz,
CD3OD): δ = 7.84 (d, J = 8.3 Hz, 2H), 7.34 (d, J = 8.1 Hz, 2H),
7.21 (s, 1H), 3.90 (s, 3H), 3.79 (s, 3H), 2.40 (s, 3H) ppm. 13
C
NMR (126 MHz, CD3OD): δ = 146.63, 144.06, 142.91, 142.81,
141.93, 138.68, 128.96, 127.73, 120.93, 109.21, 60.11, 59.75,
20.13 ppm. IR (KBr): 3249, 1610, 1596, 1493, 1462, 1424, 1334,
1305, 1142, 1082, 1039, 947 cm-1. HRMS (ESI): calcd for
C15H16NaO6S [M + Na]+ 347.0565; found 347.0566.
4.2.4. 2-((4-Methoxyphenyl)sulfonyl)benzene-1,4-diol (3d). White
o
1
solid (112 mg, 80% yield), mp 229-230 C. H NMR (500 MHz,
CD3OD): δ = 7.94-7.82 (m, 2H), 7.34 (d, J = 3.0 Hz, 1H), 7.05
(d, J = 8.9 Hz, 2H), 6.91 (dt, J = 15.9, 7.9 Hz, 1H), 6.74 (d, J =
8.8 Hz, 1H), 3.86 (s, 3H) ppm. 13C NMR (126 MHz, CD3OD): δ
4.2.11. 5-(Butylsulfonyl)-2,3-dimethoxybenzene-1,4-diol (3l).
Brown solid (74 mg, 51% yield), mp 150-152 C. H NMR (500
MHz, CD3OD): δ = 7.03 (s, 1H), 3.96 (s, 3H), 3.88 (s, 3H), 3.43-
o
1

5
3.38 (m, 2H), 1.66-1.58 (m, 2H), 1.46-1.38 (m, 2H), 0.92 (t, J =
7.4 Hz, 3H) ppm. 13C NMR (126 MHz, CD3OD): δ = 146.61,
143.07, 142.79, 141.95, 118.74, 109.70, 60.24, 59.79, 53.50,
24.40, 21.06, 12.49 ppm. IR (KBr): 3288, 1488, 1465, 1425,
1320, 1288, 1128, 1094, 1040, 952 cm-1.
7.6 Hz, 1H), 7.02 (d, J = 8.3 Hz, 2H), 6.91 (s, 1H), 3.80 (s, 3H)
ACCEPTED MANUSCRIPT
ppm. 13C NMR (126 MHz, CD3OD): δ = 163.89, 146.63, 146.33,
133.27, 128.97, 128.28, 126.52, 125.97, 122.97, 122.11, 116.68,
114.22, 102.32, 54.86 ppm. IR (KBr): 3382, 2562, 2516, 1594,
1578, 1497, 1443, 1314, 1266, 1131, 1024, 787, 682 cm-1. HRMS
(ESI): calcd for C17H15O5S [M + H]+ 331.0640; found 331.0629.
4.2.12. 2,3-Dimethoxy-5-((4-nitrophenyl)sulfonyl)benzene-1,4-
o
1
diol (3m). White solid (110 mg, 62% yield), mp 194-195 C. H
NMR (500 MHz, CD3OD): δ = 8.42-8.38 (m, 2H), 8.22-8.18 (m,
2H), 7.26 (s, 1H), 3.92 (s, 3H), 3.79 (s, 3H) ppm. 13C NMR (126
MHz, CD3OD): δ = 150.39, 147.35, 147.23, 143.22, 143.13,
142.01, 129.28, 123.52, 119.63, 109.32, 60.14, 59.74 ppm. IR
(KBr): 3425, 3261, 1609, 1538, 1466, 1425, 1307, 1285, 1147,
1100, 1041, 951 cm-1. HRMS (ESI): calcd for C14H13NNaO8S
[M + Na]+ 378.0260; found 378.0254.
4.2.19. 2-((4-Chlorophenyl)sulfonyl)naphthalene-1,4-diol (5d).
Brown solid (159 mg, 95% yield), mp 201-203 oC. 1H NMR (500
MHz, CD3OD): δ = 8.28 (d, J = 8.3 Hz, 1H), 8.19 (d, J = 8.1 Hz,
1H), 8.01-7.96 (m, 2H), 7.68-7.55 (m, 4H), 6.98 (s, 1H) ppm. 13
C
NMR (126 MHz, CD3OD): δ = 146.89, 146.76, 140.73, 139.64,
129.26, 129.23, 128.55, 128.48, 126.65, 126.11, 122.91, 122.24,
116.51, 102.23 ppm. IR (KBr): 3444, 3329, 1579, 1273, 1134,
1092, 756, 669 cm-1. HRMS (ESI): calcd for C16H12ClO4S [M +
H]+ 335.0145; found 335.0137.
4.2.13. 3,5-Dichloro-2-tosylbenzene-1,4-diol (3n). White solid
(125 mg, 75% yield), mp 173-175 oC. 1H NMR (500 MHz,
CD3OD): δ = 7.84 (d, J = 8.4 Hz, 2H), 7.45 (dd, J = 23.8, 8.4 Hz,
2H), 7.12 (d, J = 15.2 Hz, 1H), 2.45 (s, 3H) ppm.13C NMR (126
MHz, CD3OD): δ = 151.40, 145.48, 143.99, 137.91, 130.41,
129.40, 127.40, 120.28, 119.33, 118.32, 20.22 ppm. IR (KBr):
3416, 3104, 1592, 1571, 1448, 1288, 1222, 1131, 1117, 1071,
860, 679 cm-1. HRMS (ESI): calcd for C13H10Cl2NaO4S [M +
Na]+ 354.9575; found 354.9565.
4.2.20. 2-((4-(Trifluoromethyl)phenyl)sulfonyl)naphthalene-1,4-
o
1
diol (5e). Brown solid (166 mg, 90% yield), mp 161-163 C. H
NMR (500 MHz, CD3OD): δ = 8.26 (d, J = 8.4 Hz, 1H), 8.19 (d,
J = 8.3 Hz, 3H), 7.90 (d, J = 8.3 Hz, 2H), 7.64 (t, J = 7.2 Hz,
1H), 7.58 (t, J = 7.2 Hz, 1H), 7.05 (s, 1H) ppm. 13C NMR (126
MHz, CD3OD): δ = 147.01, 145.79, 134.24, 129.36, 128.57,
127.73, 126.70, 126.17, 126.13, 126.10, 126.07, 122.88, 122.30,
116.47, 102.26 ppm. IR (KBr): 3448, 3350, 1578, 1442, 1404,
1324, 1175, 1132, 1062, 857, 717, 667 cm-1. HRMS (ESI): calcd
for C17H12F3O4S [M + H]+ 369.0408; found 369.0389
4.2.14. 3,5-Dichloro-2-(phenylsulfonyl)-benzene-1,4-diol (3o).
o
1
White solid (88 mg, 55% yield), mp 171-173 C. H NMR (500
MHz, CD3OD): δ = 7.97 (d, J = 7.5 Hz, 2H), 7.76-7.67 (m, 1H),
7.62 (t, J = 7.8 Hz, 2H), 7.12 (s, 1H) ppm. 13C NMR (126 MHz,
CD3OD): δ = 151.54, 144.05, 140.94, 133.90, 130.61, 128.90,
127.26, 120.29, 119.06, 118.37 ppm. IR (KBr): 3439, 1924,
1563, 1463, 1447, 1288, 1217, 1137, 1118, 1073, 861, 730, 630
cm-1.
4.2.21. 2-((4-Nitrophenyl)sulfonyl)naphthalene-1,4-diol (5f).
Brown solid (154 mg, 89% yield), mp 167-169 oC. 1H NMR (500
MHz, CD3OD): δ = 8.43-8.38 (m, 2H), 8.24 (dd, J = 7.0, 1.9 Hz,
3H), 8.20 (d, J = 8.3 Hz, 1H), 7.68-7.62 (m, 1H), 7.62-7.56 (m,
1H), 7.08 (s, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ =
150.54, 147.43, 147.12, 147.06, 129.42, 128.63, 128.45, 126.75,
126.23, 124.08, 122.85, 122.34, 116.67, 102.23 ppm. IR (KBr):
3355, 3108, 1531, 1350, 1295, 1136, 1074, 853, 738, 557 cm-1.
HRMS (ESI-TOF): calcd for C16H10NO6S [M - H]- 344.0229;
found 344.0236.
4.2.15. 3,5-Dichloro-2-((4-nitrophenyl)sulfonyl)-benzene-1,4-diol
o
1
(3p). White solid (98 mg, 54% yield), mp 174-176 C. H NMR
(500 MHz, CD3OD): δ = 8.47-8.43 (m, 2H), 8.24-8.20 (m, 2H),
7.11 (s, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ = 151.65,
150.84, 146.56, 144.25, 131.19, 128.82, 124.03, 120.32, 118.54,
118.38 ppm. IR (KBr): 3457, 3334, 3289, 1606, 1532, 1459,
1349, 1302, 1143, 866, 852, 741, 684 cm-1.
4.2.22. 2-((2-Bromophenyl)sulfonyl)naphthalene-1,4-diol (5g).
Brown solid (178 mg, 94% yield), mp 196-198 oC. 1H NMR (500
MHz, CD3OD): δ = 8.44 (dd, J = 8.0, 1.6 Hz, 1H), 8.29 (d, J =
8.3 Hz, 1H), 8.19 (d, J = 8.3 Hz, 1H), 7.78 (d, J = 7.9 Hz, 1H),
7.68 (ddd, J = 9.6, 8.5, 1.1 Hz, 2H), 7.64-7.54 (m, 2H), 6.74 (s,
1H) ppm. 13C NMR (126 MHz, CD3OD): δ = 148.25, 146.39,
140.06, 135.40, 134.63, 131.06, 129.22, 128.53, 127.67, 126.58,
125.92, 122.92, 122.23, 120.89, 114.27, 102.74 ppm. IR (KBr):
3485, 3350, 1629, 1580, 1470, 1307, 1158, 1143, 1025, 763, 612
cm-1. HRMS (ESI): calcd for C16H12BrO4S [M + H]+ 378.9640;
found 378.9619.
4.2.16. 2-Tosylnaphthalene-1,4-diol (5a). Brown solid (129 mg,
o
1
82% yield), mp 195-197 C. H NMR (500 MHz, CD3OD): δ =
8.27 (d, J = 8.1 Hz, 1H), 8.15 (d, J = 8.2 Hz, 1H), 7.86 (d, J = 8.3
Hz, 2H), 7.63-7.58 (m, 1H), 7.57-7.53 (m, 1H), 7.35 (d, J = 8.1
Hz, 2H), 6.92 (s, 1H), 2.36 (s, 3H) ppm. 13C NMR (126 MHz,
CD3OD): δ = 146.68, 146.61, 144.74, 139.00, 129.60, 129.07,
128.36, 126.71, 126.54, 125.96, 122.97, 122.12, 116.29, 102.30,
20.10 ppm. IR (KBr): 3440, 3289, 1602, 1582, 1457, 1319, 1276,
1127, 1091, 864, 814, 764, 685, 606 cm-1. HRMS (ESI): calcd for
C17H15O4S [M + H]+ 315.0691; found 315.0687.
4.2.23. 2-(2-Methylsulfonyl)naphthalene-1,4-diol (5h). Brown
o
1
solid (89 mg, 75% yield), mp 175-176 C. H NMR (500 MHz,
CD3OD): δ = 8.30 (d, J = 8.3 Hz, 1H), 8.22 (d, J = 8.3 Hz, 1H),
7.65 (t, J = 7.2 Hz, 1H), 7.60 (t, J = 7.3 Hz, 1H), 7.00 (s, 1H),
3.26 (s, 3H) ppm.13C NMR (126 MHz, CD3OD): δ = 146.72,
146.43, 129.13, 128.22, 126.55, 126.16, 122.87, 122.25, 116.76,
102.26, 43.07 ppm. IR (KBr): 3439, 3389, 1572, 1445, 392,
1284, 1124, 961, 758, 659 cm-1. HRMS (ESI): calcd for
C11H11O4S [M + H]+ 239.0378; found 239.0371.
4.2.17. 2-(Phenylsulfonyl)naphthalene-1,4-diol (5b). Brown solid
(144 mg, 96% yield), mp 197-198 oC. 1H NMR (500 MHz,
CD3OD): δ = 8.28 (d, J = 8.3 Hz, 1H), 8.16 (d, J = 8.3 Hz, 1H),
8.00 (d, J = 7.9 Hz, 2H), 7.62 (t, J = 7.1 Hz, 2H), 7.56 (t, J = 7.5
Hz, 3H), 6.95 (s, 1H) ppm. 13C NMR (126 MHz, CD3OD): δ =
146.78, 146.75, 141.96, 133.35, 129.15, 129.08, 128.44, 126.68,
126.59, 125.99, 122.97, 122.16, 116.16, 102.31 ppm. IR (KBr):
3417, 3343, 2533, 1574, 1449, 1286, 1133, 1070, 726, 666, 554
cm-1. HRMS (ESI): calcd for C16H13O4S [M + H]+ 301.0535;
found 301.0627.
4.2.24. 2-(Butylsulfonyl)naphthalene-1,4-diol (5i). Brown solid
(77 mg, 55% yield), mp 132-134 oC. 1H NMR (500 MHz,
CDCl3): δ = 9.55 (s, 1H), 8.39 (d, J = 8.3 Hz, 1H), 8.24 (d, J =
8.3 Hz, 1H), 7.72 (dd, J = 11.2, 4.0 Hz, 1H), 7.65 (t, J = 7.2 Hz,
1H), 6.99 (s, 1H), 6.47 (s, 1H), 3.26-3.18 (m, 2H), 1.79-1.72 (m,
2H), 1.44-1.34 (m, 2H), 0.89 (t, J = 7.4 Hz, 3H) ppm. 13C NMR
(126 MHz, CDCl3): δ = 149.24, 145.44, 129.50, 129.20, 127.31,
125.93, 123.89, 122.25, 111.53, 103.23, 56.78, 24.28, 21.43,
4.2.18. 2-((4-Methoxyphenyl)sulfonyl)naphthalene-1,4-diol (5c).
Brown solid (144 mg, 87% yield), mp 152-154 oC. 1H NMR (500
MHz, CD3OD): δ = 8.27 (d, J = 8.3 Hz, 1H), 8.15 (d, J = 8.3 Hz,
1H), 7.91 (d, J = 8.2 Hz, 2H), 7.60 (t, J = 7.5 Hz, 1H), 7.55 (t, J =

6
Tetrahedron
ACCEPTED MANUSCRIPT
13.47 ppm. IR (KBr): 3396, 2961, 1580, 1471, 1278, 1263,
References
1250, 1120, 1075, 764, 666, 625 cm-1. HRMS (ESI): calcd for
C14H17O4S [M + H]+ 281.0848; found 281.0845.
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temperature until the reaction was complete. The mixture was
filtered and the filtrate was evaporated. The crude product was
subjected to flash chromatography on silica gel to give the title
o
compound (160 mg, 80%) as a white solid. Mp: 165-166 C. H
NMR (CDCl3, 500 MHz): δ = 8.11-8.08 (m, 1H), 8.05-8.02 (m,
3H), 7.84 (s, 1H), 7.79 (dd, J = 3.0 Hz, 6.0 Hz, 2H), 7.39 (d, J =
8.5 Hz, 2H), 2.45 (s, 3H) ppm.
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A
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o
anhydrous acetone (10 mL) was stirred at 50 C for 6 h. Upon
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completion of the reaction, the solvent was removed under
reduced pressure and the residue was purified by flash
chromatography on silica gel with ethyl acetate and petroleum
ether as eluents to give the title compound (96 mg, 60%) as a
o
1
brown solid. Mp: 100-103 C. H NMR (500 MHz, CDCl3): δ =
8.40-8.34 (m, 1H), 8.16-8.10 (m, 1H), 7.98 (s, 1H), 7.70-7.62 (m,
2H), 7.59 (s, 1H), 6.29 (ddd, J = 22.6, 10.7, 5.4 Hz, 1H), 5.61
(dd, J = 17.2, 1.5 Hz, 1H), 5.41 (dd, J = 10.5, 1.2 Hz, 1H), 4.76
(d, J = 5.4 Hz, 2H), 3.63-3.55 (m, 2H), 1.76-1.67 (m, 2H), 1.47-
1.37 (m, 2H), 0.88 (t, J = 7.3 Hz, 3H) ppm. 13C NMR (126 MHz,
CDCl3): δ = 149.74, 147.88, 133.51, 129.01, 128.71, 128.22,
127.68, 127.43, 123.41, 122.99, 117.89, 105.34, 55.17, 24.50,
21.54, 13.51 ppm. IR (KBr): 3373, 2959, 1588, 1354, 1289,
1128, 1079, 963, 769, 539 cm-1. HRMS (ESI): calcd for
C17H20NaO4S [M + Na]+ 243.0980; found 243.0979.
4.2.27. 4-(Allyloxy)-2-(butylsulfonyl)-1-methoxynaphthalene (8).
A mixture of 7 (160 mg, 0.50 mmol, 1.0 equiv.), CH3I (115 ꢀL,
0.75 mmol, 1.5 equiv.), K2CO3 (100 mg, 0.75 mmol, 1.5 equiv.)
in anhydrous acetone (15 mL) was stirred at 50 oC for 6 h. Upon
completion of the reaction, the solvent was removed, and the
residue was purified by column chromatography on silica gel
with ethyl acetate and petroleum ether as eluents to give the title
1
product (140 mg, 84%) as an oil. H NMR (500 MHz, CDCl3): δ
= 8.38-8.28 (m, 1H), 8.20-8.10 (m, 1H), 7.70-7.62 (m, 2H), 7.26
(s, 1H), 6.38 – 6.18 (m, 1H), 5.66 – 5.54 (m, 1H), 5.45-5.34 (m,
1H), 4.79-4.73 (m, 2H), 4.07 (s, 3H), 3.56-3.49 (m, 2H), 1.71-
1.64 (m, 2H), 1.42 (dd, J = 14.9, 7.4 Hz, 2H), 0.93 – 0.86 (m,
3H) ppm. 13C NMR (126 MHz, CDCl3): δ = 152.15, 148.36,
133.53, 129.24, 128.82, 128.39, 128.27, 127.72, 123.07, 122.96,
117.83, 101.36, 56.13, 55.05, 29.72, 24.59, 21.59, 13.55 ppm. IR
(KBr): 2960, 2931, 1586, 1455, 1378, 1349, 1332, 1134, 1107,
1077, 987, 772, 546 cm-1. HRMS (ESI): calcd. for C18H22NaO4S
[M + Na]+ 357.1136; found 357.1138.
Acknowledgments
This study was financially supported by the National Natural
Science Foundation of China (21202100, 81502985).
Supplementary data
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