Catalyst-free radical fluorination of sulfonyl hydrazides in water

Article abstract of DOI:10.1039/c5gc02755a

The first catalyst-free fluorination of sulfonyl hydrazides for the synthesis of sulfonyl fluorides has been developed via a free-radical pathway. This protocol presents a broad substrate scope and does not require any metal catalyst and additive. All these transformations proceed smoothly in water under mild conditions, which enables a straightforward, practical and environmentally benign fluorination for S-F bond formation.

Full text of DOI:10.1039/c5gc02755a

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Catalyst-free radical fluorination of sulfonyl hydrazides in water
a
b
b
a
b
Lin Tang,* Yu Yang, Lixian Wen, Xingkun Yang and Zhiyong Wang*
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
www.rsc.org/
1
4
The first catalyst-free fluorination of sulfonyl hydrazides for the a large excess of oxidation is employed.
synthesis of sulfonyl fluorides has been developed via a free- Green chemistry can be defined as the synthesis of
radical pathway. This protocol presents broad substrate scope and important chemical and biological products from available
does not require any metal catalyst and additive. All these readily and inexpensive starting materials through atom
transformations proceeds smoothly in water under mild economical and environmentally benign strategies. To achieve
conditions, which enables
a straightforward, practical and these goals, chemists have devoted themselves to developing
1
green and sustainable catalytic system, such as recyclable or
5
environmentally benign fluorination for S-F bond formation.
1
6
metal-free catalysts instead of metal catalysts. It is obvious
that catalyst-free reactions are more attractive because of
their advantages of being atom economical and inexpensive.
Furthermore, water is a cost-effective and environmentally
The observation that fluorine introduction into drugs often
leads to significantly promoted medicinal properties has
1
revolutionized the development of pharmaceuticals.
1
8
1
7
Furthermore, radioactive F-labeled organic compounds are
also widely employed as contrast agents for positron emission
benign solvent in synthetic chemistry. Therefore, reactions
proceeding in water under catalyst-free conditions, are in
accord with green chemistry. As an ongoing interest in the
2
tomography (PET). Recently, transition metal-catalyzed (or
1
8
mediated) fluorination of the substrates bearing various
6
development of green chemical reactions,
we herein
3
4
5
functional groups, including halogen, OTf, OCO R, COOH,
2
developed an efficient fluorination of sulfonyl hydrazides for S-
F bond formation in water without any catalyst and additive
7
SPO(OEt) , SnBu , BF K, etc., has been widely reported in
8
9
10
2
3
3
18e
Scheme 1c). Our idea derived from our recent study that
the presence of fluorine source, because they offer good
control of regioselectivity (Scheme 1a). Very recently, Sammis
has successfully developed decarboxylative radical fluorination
(
the sulfonyl hydrazides could be converted to sulfinic acid in
6
b
water, and Li’s work that the combination of 1-chloromethyl-
-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)
1
1
under transition metal-free conditions (Scheme 1b).
4
Nevertheless, the aforementioned methods for C-F bond
formation are restricted because of the use of expensive
transition metal catalysts, excess fluorine reagents or toxic
organic solvents. Comparatively little interest has been paid to
S-F bond formation. The sulfonyl fluoride functional group is a
valuable structural motif due to its widespread occurrence in
(
Selectfluor) and Ag(I) catalyst could serve as oxidant and fluo-
Previous work:
F source
a
R
X
R
F
transition metal
1
2
R = Aryl, alkyl
X = halogen, OTf, OMs, COOH,
SPO(OEt) , SnBu , BF K, etc.
biologically active molecules. Methods for the preparation of
sulfonyl fluorides, however, are limited. The traditional
approach mainly relies on nucleophilic substitution of sulfonyl
chlorides with the fluoride anion, which requires strict
2
3
3
O
F source (5.0 equiv.)
b
R
R
2
13
1
R
1
F
anhydrous conditions. A recent reaction for synthesizing
sulfonyl fluorides from thiosulfonates is reported even though
benzene,110 o
O
C
This work
：
O
S
O
S
NH
NH
2
Selectfluor (1.3 equiv.)
O, 60 o
c
R
R
F
O
H
2
C
O
Scheme 1 Strategies for the incorporation of fluorine.
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Journal Name
Cl
delight, 4-methylbenzenesulfonyl fluoride (2a) was observed in
4% yield in the presence of Selectfluor (entry 1). However,
water-insoluble Ag CO and AgCl could also afford 2a in good
O
S
N
7
N
R
F
F
O
2
3
Cl
yields of 76% and 77%, respectively (entries 2 and 3). We
inferred from the obtained results that silver salts were not
crucial for this fluorination. As expected, the reaction could
N
Ag(I)
N
O
S
+
proceed well in the absence of silver salts (entry 4). F sources
F
Ag(III)
F
Ag(II)
R
O
of N-fluorobenzenesulfonimide (NFSI) and 1-fluoro-2,4,6-
trimethylpyridinium tetrafluoroborate (FTPT) could also give
the corresponding product in the yield up to 79% (entries 5
O
S
O
O
-
NH
H
2
S
and 6). However, the fluorination could not take place when F
S
R
N
H
R
O-
R
O
O
+
sources of CsF and tetrabutylammonium fluoride (TBAF) were
employed (entries 7 and 8). In consideration of the expensive
price of FTPT, we chose Selectfluor as the F sources to
optimize the reaction conditions. Subsequently, various
solvents were tested in the reaction. Low yields (< 64%) were
obtained when the solvents were CH CN, THF and H O, which
2
O
N2 + H O
3
Scheme 2 Initial hypothesis mechanism for Ag(I)-catalyzed
fluorination of sulfonyl hydrazides.
a
Table 1 Optimization of the reaction conditions
3
2
could perhaps be attributed to the poor solubility of the
substrate (entries 9-11). Then we employed DMSO as the
solvent, relatively high yield of 74% was obtained (entries 12).
Nevertheless, 2a was obtained only in 42% yield when EtOH
served as the solvent, because there was a side reaction of 2a
with EtOH (entry 13).
O
S
NH2
NH
O
S
Conditions
F
O
O
1a
2a
Entry
Catalyst
F source
Solvent
Yieldb (%)
We also studied the influence of temperature on the
reaction (Fig. 1). The yield rapidly increased in solvents of H O
2
1
2
3
4
5
6
7
8
9
AgNO
3
Selectfluor
Selectfluor
Selectfluor
Selectfluor
NFSI
CH
CH
CH
3
CN:H
CN:H
CN:H
2
2
2
O (1:1)
74
76
and CH CN when the reaction temperature was elevated from
3
2
Ag CO
3
3
O (1:1)
O (1:1)
o
o
5 C to 40 C. Pleasingly, the highest yield of 94% was given in
2
o
water when the temperature was 60 C, even though low yield
AgCl
3
77
o
of 63% was afforded at 25 C in comparison with in the solvent
-
-
-
-
-
-
-
-
-
-
CH CN:H O (1:1)
77
3
2
2
2
2
2
of DMSO and CH CN:H O (1:1). These results indicated that the
2
3
reaction could be facilitated by water.
CH
CH
CH
CH
3
CN:H
CN:H
CN:H
CN:H
O (1:1)
O (1:1)
O (1:1)
O (1:1)
73
With the optimal conditions in hand, the scope of sulfonyl
hydrazides was extended (Table 2). Substrates with electron-
donating groups (methyl, n-propyl, t-butyl and methoxyl) and
halogen (fluoro and chloro) on the benzene ring, regardless of
the large steric hindrance of substitution (2,4,6-trimethyl),
gave the corresponding products of 2a-2g in good yields.
However, relatively low yield of 2h was obtained, due to the
poor solubility of the substrate in water. Moderate yields were
afforded when electron-withdrawing groups were present (2i-
FTPT
3
79
CsF
3
n.d.
n.d.
58
TBAF
3
Selectfluor
Selectfluor
Selectfluor
Selectfluor
Selectfluor
CH CN
3
1
1
1
1
0
1
2
3
THF
55
H
2
O
63
2l). It is interesting to note that the steric hindrance of nitro
DMSO
EtOH
74
42
a
Reaction conditions: 1a (0.25 mmol), catalyst (0.025 mmol), F
o
b
source (0.325 mmol), solvent (1.0 ml), 25 C, 14 h. Isolated
yield.
rine atom transfer agent. In this context, we hypothesized that
Ag(I)-catalyzed fluorination of sulfonyl hydrazides could be
achieved in water via a free-radical pathway (scheme 2).
We began our study with 4-methylbenzenesulfonohydrazide
(
1a) as the model substrate in the solvent of CH
3 2
CN:H O (v:v =
1:1) (Table 1). Initial experiments were performed to
investigate the influence of catalysts on the reaction. Since
water-soluble silver salts have been the most successful for
Fig. 1 Temperature effect on the reaction in different solvents.
3
fluorination, we firstly employed AgNO as the catalyst. To our
2
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SO NHNH2 standard conditions
SO2F
2
group was favourable to the fluorination process (2l-2n).
Naphthalene-2-sulfonyl fluoride could also be achieved in an
excellent yield (2q). Remarkably, aromatic heterocycle of
thiophene was well tolerated in the reaction, yielding
fluorinated product of 2r. Moreover, aliphatic sulfonyl
hydrazides were successfully employed as the substrates to
a
b
1
u
2u, 90%
SO
2
NHNH
2
standard conditions
TEMPO (2.0 equiv.)
2
SO F
give the corresponding products in good yields (2s, 2t). We
were pleased to find that 1.86 gram (10 mmol) scale of 1a was
successfully converted to give 2a in 88% yield.
1u
2u, n.d.
a,b
SO Na
standard conditions
SO2F
2
Table 2 Scope of sulfonyl hydrazides
O
O
S
c
NH
2
Selectfluor
R
S
NH
R
F
o
H O, 60 C
2
O
3u
2u, 87%
2u, 83%
O
1
2
SO
2
Na
standard conditions
TEMPO (2.0 equiv.)
2
SO F
d
2
SO F
SO F
2
SO2F
3
u
Scheme 3 control experiments for the reaction mechanism.
2
a, 94% (88%)c
2b, 92%
2c, 91%
H
2
O
N
2
+ H
3
O+
SO2F
SO2F
O
S
O
S
O
S
SO2F
O
S
R
NHNH
2
R
O
R
O
rapidly
R
F
O
H
3
CO
F
a
b
O
Cl
Cl
2d, 87%
2e, 82%
2f, 81%
2i, 69%
2l, 53%
N
N
N
N
+
F
F
c
SO
2
F
SO
2
F
2
SO F
Scheme 4 Plausible reaction mechanism.
a,b
Cl
I
F
3
CO
Table 3 Scope of sodium arylsulfinates
O
S
2
g, 75%
2h, 54%
Selectfluor
ArSO
2
Na
R
F
o
2
H O, 60 C
O
SO2F
SO2F
SO2F
O
3
2
F
3
C
N
H
2
O N
SO
2
F
SO
F
SO F
2
2
2
j, 76%
2k, 62%
SO2F
SO2F
F
SO2F
2u, 87%
2
a, 94%
2c, 88%
Cl
NO
2
NO2
SO F
2
SO2F
SO2F
2
m, 90%
2n, 95%
2o, 91%
F
Cl
3
F CO
Br
SO
2
F
2
SO F
S
2
f, 79%
2g, 68%
2i, 61%
SO2F
SO
2
F
SO
2
F
2
SO F
O
CF3
F
3
C
N
H
2
O N
2
p, 72%
2q, 96%
2r, 77%
2
j, 69%
2k, 63%
2l, 54%
2
SO F
SO2F
SO2F
S
2
SO F
2s,95%
2t, 82%
a
2
q, 85%
2r, 76%
Reaction conditions:
water (1.0 ml), 60 C, 14 h. Isolated yield. 1a (10 mmol, 1.86
1 (0.25 mmol), Selectfluor (0.325 mmol),
o
b
c
a
Reaction conditions:
water (1.0 ml), 60 C, 14 h. Isolated yield.
3 (0.25 mmol), Selectfluor (0.325 mmol),
g).
o
b
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To get an insight into the reaction mechanism, several
control experiments were conducted to confirm which
pathway this fluorination takes (Scheme 3) (see the supporting
information for two possible reaction pathways). First, 1u
could give the product 2u in 90% yield under the standard
conditions and the pH value of the solution after reaction was
2
3
(a) M. E. Phelps, Proc. Natl. Acad. Sci. U.S.A., 2000, 97, 9226;
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(
2
,
1
2
.02 (a), whereas radical inhibitor TEMPO (2,2,6,6-tetramethyl-
-piperidinyloxy) was introduced to the reaction, the
Mu, H. Zhang, P. Chen, G. Liu, Chem. Sci., 2014, 5, 275; (f) A.
1
I. Konovalov, E. O. Gorbacheva, F. M. Miloserdov, V. V.
Grushin, Chem. Commun., 2015, 51, 13527.
(a) D. A. Watson, M. J. Su, G. Teverovskiy, Y. Zhang, J.
formation of 2u was completely suppressed, which suggested
that the reaction took place via a free-radical pathway (b).
Furthermore, 2u could also be obtained in 87% yield when
sodium benzenesulfinate served as the substrate (c). However,
TEMPO was found to have little influence on this reaction (d).
The results implied that benzenesulfinate was not the
intermediate of this fluorination.
4
5
GarciaFortanet, T. Kinzel, S. T. Buchwald, Science, 2009, 325
661; (b) M. N. Stewart, B. G. Hockley, P. J. H. Scott, Chem.
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,
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(a) C. Hollingworth, A. Hazari, M. N. Hopkinson, M. Tredwell,
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Benedetto, M. Tredwell, C. Hollingworth, T. Khotavivattana, J.
On the basis of the results described above and previous
1
8e,19
M. Brown, V. Gouverneur, Chem. Sci., 2013, 4, 89.
reports,
Sulfonyl hydrazide can react with Selectfluor to form fluorine
and free radical by liberating nitrogen in the presence of
water and an acidic solution is obtained. Then can resonate
with which rapidly captures fluorine to generate the final
product of sulfonyl fluoride.
a plausible mechanism was proposed (Scheme 4).
6
(a) T. Gustafsson, R. Gilmour, P. H. Seeberger, Chem.
Commun., 2008, 3022; (b) F. Yin, Z. Wang, Z. Li, C. Li, J. Am.
Chem. Soc., 2012, 134, 10401; (c) X. Wu, C. Meng, X. Yuan, X.
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a
a
b
7
8
A. M. Lauer, J. Wu, Org. Lett., 2012, 14, 5138.
(a) T. Furuya, A. E. Strom, T. Ritter, J. Am. Chem. Soc., 2009,
The result of Scheme 3c showed that sodium
benzenesulfinate could also react well with Selectfluor. To
further establish the general utility of these transformations,
sodium arylsulfinates were employed as the substrates to
synthesize sulfonyl fluorides (Table 3). Substrates bearing
electron-donating groups (methyl and t-butyl) could give the
products in good yields (2a and 2c). However, only moderate
yields were achieved when electron-withdrawing groups were
1
1
31, 1662; (b) Y. Ye, M. S. Sanford, J. Am. Chem. Soc., 2013,
35, 4648.
9
1
A. R. Mazzotti, M. G. Campbell, P. Tang, J. M. Murphy, T.
Ritter, J. Am. Chem. Soc., 2013, 135, 14012.
0 For selected examples of transition metal-catalyzed
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Chem. Rev., 2008, 108, 1943; (b) C. Hollingworth, V.
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present on the benzene ring (2f
, 2g, 2i, 2j, 2k and 2l). Similarly,
Ritter, Chem. Sci., 2014,
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Woltornist, A. Griswold, M. G. Holl, T. Lectka, Org. Lett., 2013,
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2r
in 76% yield.
1
5, 1722; (f) M.-G. Braun, A. G. Doyle, J. Am. Chem. Soc.,
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In summary, we have firstly developed a highly efficient
2
Rev., 2015, 115, 612.
protocol for the synthesis of sulfonyl fluorides by taking
advantage of a metal-free radical fluorination strategy. It is 11 M. Rueda-Becerril, C. C. Sazepin, J. C. T. Leung, T. Okbinoglu,
P. Kennepohl, J.-F. Paquin, G. M. Sammis, J. Am. Chem. Soc.,
noteworthy that this method is distinguished by (1) no use of
2
012, 134, 4026.
any transition metal; (2) the lack of any additive; (3)
operational simplicity; (4) water as the solvent; (5) air
atmosphere, (6) broad substrate scope and (7) gram-scale
synthesis. Detailed mechanistic studies and further
applications of the reaction are ongoing in our laboratory.
Financial support from the National Natural Science
Foundation of China (2127222, 91213303, 21172205,
1
2 (a) C. Gu, Chem. Biol., 2013, 20, 541; (b) N. P. Grimster, S.
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20932002) is greatly acknowledged.
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8 (a) Y. Wang, D. Zhu, L. Tang, S. Wang, Z. Wang, Angew.
Chem., Int. Ed., 2011, 50, 8917; (b) L. Tang, H. Sun, Y. Li, Z.
Zha, Z. Wang, Green Chem., 2012, 14, 3423; (c) L. Tang, X.
Guo, Y. Li, S. Zhang, Z. Zha, Z. Wang, Chem. Commun., 2013,
49, 5213; (d) X. Guo, L. Tang, Y. Yang, Z. Zha, Z. Wang, Green
Chem., 2014, 16, 2443; (e) Y. Yang, L. Tang, S. Zhang, X. Guo,
Z. Zha, Z. Wang, Green Chem., 2014, 16, 4106.
9 (a) Q. Lu, J. Zhang, F. Wei, Y. Qi, H. Wang, Z. Liu, A. Lei,
Angew. Chem., Int. Ed., 2013, 52, 7156; (b) W. Wei, C. Liu, D.
Yang, J. Wen, J. You, Y. Suo, H. Wang, Chem. Commun., 2013,
49, 10239; (c) Q. Lu, J. Zhang, G. Zhao, Y. Qi, H. Wang, A. Lei,
J. Am. Chem. Soc., 2013, 135, 11481.
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The first catalyst-free fluorination of sulfonyl hydrazides for the synthesis of sulfonyl fluorides via a free-radical process
has been developed.

Page 7 of 45
Green Chemistry
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DOI: 10.1039/C5GC02755A
Supporting Information
Catalyst-free radical fluorination of sulfonyl hydrazides in water
a
b
b
a
b
Lin Tang,* Yu Yang, Lixian Wen, Xingkun Yang and Zhiyong Wang*
a
College of Chemistry and Chemical Engineering, Xinyang Normal University,
Xinyang, Henan 464000, China. Eꢀmail: lintang@xynu.edu.cn
b
Hefei National Laboratory for Physical Sciences at Microscale, CAS Key
Laboratory of Soft Matter Chemistry and Department of Chemistry, University of
Science and Technology of China, Hefei, Anhui 230026, China. Eꢀmail:
zwang3@ustc.edu.cn
Contents:
General experimental procedures................................................................................S2
Two possible reaction pathways..................................................................................S2
Characterization data of products 2a-2u......................................................................S3
1
13
19
H, C and F NMR spectra of products 2a-2u.........................................................S8
S1

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DOI: 10.1039/C5GC02755A
General experimental procedures
Solvent
of
water
(1.0
ml)
was
added
to
the
mixture
of
4
-methylbenzenesulfonohydrazide (46.5mg, 0.25 mmol), Selectfluor (115.1 mg, 0.325
mmol) in a Schlenk tube. The reaction mixture was stirred at 60 °C for 14 h. After
cooling to room temperature, 5 times the volume of EtOAc was added to the reaction
mixture under vigorous stirring conditions. Then, the solvent of the organic phase was
removed under vacuum and the residue was purified by flash column chromatography
(
petroleum ether/ethyl acetate = 8:1) to give the product as a white solid in 94% yield.
1
Proton nuclear magnetic resonance ( H NMR) spectra and carbon nuclear magnetic
resonance ( C NMR) spectra were recorded on a Bruker AC-400 FT ( H NMR 400
MHz, C NMR 100 MHz) using TMS as an internal reference. F fluorine spectra
were recorded on either a Bruker AC-400 FT ( F NMR 376 MHz) using CFCl
external reference.
13
1
13
19
19
3
as an
Two possible reaction pathways
N + H
O+
2 3
H
2
O
O
S
O
S
O
S
A
O
S
R
NHNH2
R
O
R
O
O
R
F
O
Cl
N
N
F
H O
N
2
+ H
O+
3
2
O
S
O
S
O
S
O
S
B
R
NHNH
2
R
O
R
O
O
R
F
O
Cl
Cl
N
N
N
+
F
N
F
Scheme S1 the possible processes for this fluorination.
S2

Page 9 of 45
Green Chemistry
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DOI: 10.1039/C5GC02755A
Characterization data of products 2a-2u
4
-methyl-benzenesulfonyl fluoride (2a)
O
S
F
O
1
H NMR (400 MHz, CDCl
3
): δ [ppm] = 7.89 (d, 8.0 Hz, 2H), 7.42 (d, 8.0 Hz, 2H), 2.49 (s, 3H);
13
19
C NMR (100 MHz, CDCl
3
): δ [ppm] = 147.2, 130.4, 130.3, 130.1, 128.6, 22.0; F NMR (376
[1]
MHz, CDCl
3
): δ [ppm] = 66.2. This compound was known.
4
-propyl-benzenesulfonyl fluoride (2b)
O
S
F
O
1
3
H NMR (400 MHz, CDCl ): δ [ppm] = 7.91 (d, 8.0 Hz, 2H), 7.42 (d, 8.0 Hz, 2H), 2.71 (t, 7.8 Hz,
13
2
H), 1.73-1.64 (m, 2H), 0.96 (t, 7.8 Hz, 3H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 151.8,
19
1
30.5, 130.2, 129.8, 128.6, 38.2, 24.2, 13.8; F NMR (376 MHz, CDCl ): δ [ppm] = 66.3. This
3
[1]
compound was known.
4
-tert-butyl-benzenesulfonyl fluoride (2c)
O
S
F
O
1
H NMR (400 MHz, CDCl
3
): δ [ppm] = 7.93 (d, 8.0 Hz, 2H), 7.63 (d, 8.0 Hz, 2H), 1.37 (s, 9H);
13
19
C NMR (100 MHz, CDCl
3
): δ [ppm] = 160.1, 130.2, 130.0, 128.5, 126.8, 35.7, 31.1; F NMR
[1]
(376 MHz, CDCl
3
): δ [ppm] = 66.2. This compound was known.
2
-(4-Methoxyphenyl)-benzoxazole (2d)
O
S
O
F
O
1
H NMR (400 MHz, CDCl ): δ [ppm] = 7.94 (d, 8.5 Hz, 2H), 7.06 (d, 8.5 Hz, 2H), 3.92 (s, 3H);
3
13
19
C NMR (100 MHz, CDCl
3
): δ [ppm] = 165.3, 131.0, 124.3, 124.1, 115.0, 56.0; F NMR (376
[1]
MHz, CDCl
3
): δ [ppm] = 67.3. This compound was known.
2
,4,6-trimethyl-benzenesulfonyl fluoride (2e)
S3

Green Chemistry
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DOI: 10.1039/C5GC02755A
O
S
F
O
1
13
H NMR (400 MHz, CDCl
100 MHz, CDCl
376 MHz, CDCl ): δ [ppm] = 68.2. This compound was known.
3
): δ [ppm] = 7.03 (s, 2H), 2.64 (d, 1.2 Hz, 6H), 2.35 (s, 3H); C NMR
19
(
(
3
): δ [ppm] = 145.2, 140.2, 132.0, 132.0, 129.3, 129.1, 22.5, 22.5, 21.3; F NMR
[1]
3
4
-fluoro-benzenesulfonyl fluoride (2f)
O
F
S
F
O
1
13
H NMR (400 MHz, CDCl
3
MHz, CDCl ): δ [ppm] = 168.3, 165.7, 131.8, 131.7, 117.5, 117.3; F NMR (376 MHz, CDCl ): δ
3
): δ [ppm] = 8.08-8.04 (m, 2H); 7.32 (t, 8.0 Hz, 2H); C NMR (100
19
3
[1]
[ppm] = 66.8. This compound was known.
4
-chloro-benzenesulfonyl fluoride (2g)
O
Cl
S
F
O
1
13
H NMR (400 MHz, CDCl
MHz, CDCl ): δ [ppm] = 142.7, 131.5, 131.2, 130.1, 129.9; F NMR (376 MHz, CDCl
66.5. This compound was known.
3
): δ [ppm] = 7.98-7.94 (m, 2H), 7.63-7.60 (m, 2H); C NMR (100
19
3
3
): δ [ppm]
[1]
=
4
-iodo-benzenesulfonyl fluoride (2h)
O
I
S
F
O
1
13
H NMR (400 MHz, CDCl
3
): δ [ppm] = 8.01 (d, 8.0 Hz, 2H), 7.71 (d, 8.0 Hz, 2H); C NMR (100
19
MHz, CDCl
3
): δ [ppm] = 139.2, 132.9, 129.6, 104.2; F NMR (376 MHz, CDCl
3
): δ [ppm] = 66.2.
[1]
This compound was known.
4
-trifluoromethoxy-benzenesulfonyl fluoride (2i)
O
O
F
S
F
F
F
O
1
13
H NMR (400 MHz, CDCl
3
): δ [ppm] = 8.09 (d, 8.0 Hz, 2H), 7.46 (8.0 Hz, 2H); C NMR (100
1
9
MHz, CDCl
3
): δ [ppm] = 154.3, 131.1, 130.9, 130.8, 124.0, 121.4, 121.2, 118.8, 116.2; F NMR
S4

Page 11 of 45
Green Chemistry
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DOI: 10.1039/C5GC02755A
3 7 4 4 3
(376 MHz, CDCl ): δ [ppm] = 66.5, -57.7. HRMS (M+) calcd for C H F O S: 243.9817 found
243.9811.
4
-trifluoromethyl-benzenesulfonyl fluoride (2j)
O
S
F
F
F
F
O
1
13
H NMR (400 MHz, CDCl
3
): δ [ppm] = 8.17 (d, 8.0 Hz, 2H), 7.92 (d, 8.0 Hz, 2H); C NMR (100
19
MHz, CDCl
3
): δ [ppm] = 137.5, 137.2, 136.8, 129.3, 127.1, 127.1, 127.0, 127.0, 124.2, 121.5; F
[2]
NMR (376 MHz, CDCl
3
): δ [ppm] = 65.9, -63.5. This compound was known.
4
-acetylamino-benzenesulfonyl fluoride (2k)
O
S
HN
F
O
O
1
H NMR (400 MHz, CDCl
3
): δ [ppm] = 7.96 (d, 8.8 Hz, 2H), 7.79 (d, 8.8 Hz, 2H), 7.57 (s, 1H),
13
19
2
.25 (s, 3H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 168.8, 144.5, 130.2, 127.2, 119.5, 25.0; F
[1]
NMR (376 MHz, CDCl
3
): δ [ppm] = 66.8. This compound was known.
4
-nitro-benzenesulfonyl fluoride (2l)
O
S
O N
F
2
O
1
13
H NMR (400 MHz, CDCl
3
): δ [ppm] = 8.49 (d, 8.4 Hz, 2H), 8.25 (d, 8.4 Hz, 2H); C NMR (100
19
MHz, CDCl
3
): δ [ppm] = 142.8, 131.7, 131.4, 130.3, 130.0; F NMR (376 MHz, CDCl ): δ [ppm]
3
[1]
=
66.3. This compound was known.
4
-chloro-3-nitro-benzenesulfonyl fluoride (2m)
O
Cl
S
F
O
O N
2
1
H NMR (400 MHz, CDCl
3
): δ [ppm] = 8.52 (d, 2.0 Hz, 1H), 8.16-8.14 (m, 1H), 7.89 (d, 8.0 Hz,
13
19
1
H); C NMR (100 MHz, CDCl
NMR (376 MHz, CDCl ): δ [ppm] = 67.0. HRMS (M+) calcd for C
38.9459.
3
): δ [ppm] = 148.3, 135.5, 134.0, 133.0, 132.7, 132.3, 126.1;
F
3
6
H
3
ClFNO
4
S: 238.9455 found
2
S5

Green Chemistry
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2
-nitro-benzenesulfonyl fluoride (2n)
O
S
F
O
NO2
1
H NMR (400 MHz,CDCl ): δ [ppm] = 8.88 (s, 1H), 8.65 (d, 8.0 Hz, 1H), 8.36 (d, 8.0 Hz, 1H),
3
1
3
7
1
.94-7.90 (m, 1H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 148.6, 135.2, 134.9, 133.9, 131.5,
19
[2]
3
30.1, 124.0; F NMR (376 MHz, CDCl ): δ [ppm] = 66.5. This compound was known.
3
-fluoro-4-methyl-benzenesulfonyl fluoride (2o)
O
S
F
O
F
1
H NMR (400 MHz,CDCl ): δ [ppm] = 7.72-7.70 (m, 1H), 7.65 (d, 8.0 Hz, 1H), 7.47 (t, 8.0 Hz,
3
1
3
1
H); C NMR (100 MHz, CDCl
31.9, 131.7, 131.6, 124.3, 124.2, 115.6, 115.4, 15.2, 15.2; F NMR (376 MHz, CDCl
66.3, -111.9. HRMS (M+) calcd for C S: 192.0057 found 192.0065.
3
): δ [ppm] = 162.2, 159.7, 134.7, 134.5, 132.9, 132.9, 131.9,
19
1
3
): δ [ppm]
=
7 6 2 2
H F O
3
-bromo-5-trifluoromethyl-benzenesulfonyl fluoride (2p)
F3C
O
S
F
O
Br
1
13
H NMR (400 MHz,CDCl
3
): δ [ppm] = 8.34 (s, 1H), 8.20 (s, 1H), 8.16 (s, 1H); C NMR (100
MHz, CDCl
3
): δ [ppm] = 136.0, 135.7, 135.6, 135.6, 135.6, 134.7, 134.4, 134.0, 133.7, 126.1,
19
3
124.6, 124.3, 124.3, 124.2, 124.2, 123.3, 120.6, 117.9; F NMR (376 MHz, CDCl ): δ [ppm] =
[2]
66.6, -63.1. This compound was known.
naphthalene-2-sulfonyl fluoride (2q)
O
S
F
O
1
H NMR (400 MHz,CDCl
3
): δ [ppm] = 8.62 (s, 1H), 8.08-8.02 (m, 2H), 7.99-7.92 (m, 2H),
1
3
7
.78-7.68 (m, 2H); C NMR (100 MHz, CDCl ): δ [ppm] = 136.2, 132.0, 131.1, 130.5, 130.2,
3
19
1
30.1, 129.8, 129.8, 128.5, 128.3, 122.3; F NMR (376 MHz, CDCl
3
): δ [ppm] = 66.3. This
[3]
compound was known.
thiophene-2-sulfonyl fluoride (2r)
S6

Page 13 of 45
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O
S
F
S
O
1
H NMR (400 MHz, CDCl
3
): δ [ppm] = 7.94 (d, 4.0 Hz, 1H), 7.90 (d, 4.8 Hz, 1H), 7.27 (t, 4.4 Hz,
13
19
1
H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 137.0, 136.6, 136.6, 131.8, 131.5, 128.3; F NMR
[1]
(376 MHz, CDCl ): δ [ppm] = 71.8. This compound was known.
3
phenyl-methanesulfonyl fluoride (2s)
O
S
F
O
1
13
H NMR (400 MHz, CDCl
3
): δ [ppm] = 7.47-7.43 (m, 5H), 4.60 (d, 3.2 Hz, 2H); C NMR (100
1
9
MHz, CDCl
3
): δ [ppm] = 130.8, 130.1, 129.5, 125.6, 57.1, 56.9; F NMR (376 MHz, CDCl ): δ
3
[4]
[ppm] = 51.4. This compound was known.
octanesulfonyl fluoride (2t)
O
S
F
O
1
3
H NMR (400 MHz, CDCl ): δ [ppm] = 3.38-3.33 (m, 2H), 1.98-1.91 (m, 2H), 1.51-1.44 (m, 2H),
1
3
1
.33-1.28 (m, 8H), 0.89 (t, 7.2 Hz, 3H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 51.1, 50.9, 31.8,
19
2
9.0, 29.0, 28.0, 23.5, 22.7, 14.2; F NMR (376 MHz, CDCl ): δ [ppm] = 53.2. This compound
3
[5]
was known.
benzenesulfonyl fluoride (2u)
O
S
F
O
1
H NMR (400 MHz, CDCl ): δ [ppm] = 8.20 (d, 6.8 Hz, 2H), 7.96 (t, 6.8 Hz, 1H), 7.82 (t, 6.8 Hz,
3
13
19
2
H); C NMR (100 MHz, CDCl
3
): δ [ppm] = 132.8, 130.3, 130.0, 126.9, 125.6; F NMR (376
[1]
MHz, CDCl
3
): δ [ppm] = 66.2. This compound was known.
References:
1] L. Matesic, N. A. Wyatt, B. H. Fraser, M. P. Roberts, T. Q. Pham, I. Greguric, J. Org. Chem.,
013, 78, 112625.
[
2
[
[
[
2] G. Palumbo, R. Caputo, Synthesis, 1981, 888.
3] D. N. Harpp, S. J. Bodzay, Sulfur Lett., 1987, 73.
4] M. Kirihara, S. Naito, Y. Nishimura, Y. Ishizuka, T. Iwai, H. Takeuchi, T. Ogata, H. Hanai,
Y. Kinoshita, M. Kishida, K. Yamazaki, T. Noguchi, S. Yamashoji, Tetrahedron, 2014, 70, 2464.
5] J. Burdon, I. Farazmand,; M. Stacey, J. C. Tatlow, J. Chem. Soc.,1957, 2574.
[
S7

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13
19
H, C and F NMR spectra of products 2a-2u
S8

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