Difluoroaminosulfonylation of Styrenes with N,N-Difluorobenzenesulfonamide

Article abstract of DOI:10.1016/j.jfluchem.2021.109823

A new type of difluoroaminosulfonylation of styrenes with N,N-difluorobenzenesulfonamide (DFBSA) was developed, using NiCl₂/Mn as catalysts and bipyridine as the ligand, to afford a series of 1-difluoroamino-2-phenylsulfonyl products. Preliminary mechanistic studies proved a free radical process for the reaction.

Full text of DOI:10.1016/j.jfluchem.2021.109823

Journal of Fluorine Chemistry 248 (2021) 109823
Contents lists available at ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Difluoroaminosulfonylation of Styrenes with N,
N-Difluorobenzenesulfonamide
,b,*
Wenqing Zhanga, Xianjin Yanga
a Key Lab for Advanced Material & Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
b Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
A R T I C L E I N F O
A B S T R A C T
Keywords:
A new type of difluoroaminosulfonylation of styrenes with N,N-difluorobenzenesulfonamide (DFBSA) was
developed, using NiCl2/Mn as catalysts and bipyridine as the ligand, to afford a series of 1-difluoroamino-2-phe-
nylsulfonyl products. Preliminary mechanistic studies proved a free radical process for the reaction.
Styrenes
N-Fluorobenzenesulfonamide
N,N-Difluorobenzenesulfonamide
Difluoroaminosulfonylation
Difunctionalization
1. Introduction
2. Results and discussion
Amines and sulfones are key synthons in many synthetic trans-
formations, such as the diazotization of amines [1] and the
Junia-Lythgoe olefination of sulfones [2]. More importantly, the amines
[3] and the sulfones [4] are widely present in natural products,
small-molecule therapeutics and biopharmaceuticals, and agrochemi-
cals, and can engender a variety of biological activities, rendering them
important functionalities in the structures of various medicines and
agrochemical reagents (Fig.1) [5]. Although there are many mature
methods for introducing amines and sulfones into molecules [6, 7], most
of them are achieved through multi-step synthesis, and there are few
reports on the simultaneous introduction of these two functionalities
into molecules [8].
Fluorine is the most electronegative element in nature, and its atomic
radius is the closest to that of hydrogen. Therefore, the introduction of
fluorine atoms into molecules often improves the efficacies of drugs and
affects the reactivities of chemical reagents. In this communication, we
designed and synthesized N,N-difluorobenzenesulfonamide (DFBSA, 1)
to evaluate its propensity for enabling the direct aminosulfonylation of
styrene. It was hypothesized that the inductive effect of the fluorine
atoms in DFBSA will weaken the N–S bond to promote the difluor-
oaminosulfonylation of alkenes. DFBSA was obtained in yields of up to
73% by the reaction of N-fluorobenzenesulfonamide with Selectfluor at
0 ◦C in acetone in the presence of NaOH (Scheme 1). We found that the
N–F bond in DFBSA was very stable and surprisingly difficult to cleave,
indicating that DFBSA is stable in water.
One of the most effective and direct methods to simultaneously
introduce two functional groups into a molecule is by the difunction-
alization of alkenes. One such type of conversion is the amination of
alkenes, including diamination [9], aminohalogenation [10], amino-
oxygenation [11], and aminoalkylation [12], which can lead to the
generation of valuable nitrogen-containing molecules. However, few
reports have been successful in achieving the simultaneous amino-
sulfonylation of alkenes, and, as such this conversion still remains a
synthetic challenge.
Initially, the reaction of DFBSA (1a) with styrene was selected as the
model reaction to optimize the reaction conditions, and the represen-
tative results are shown in Table 1. The solvent screening revealed that
EtOAc was the most suitable solvent to afford the target product 3a.
Other evaluated solvents, such as CH3SOCH3 and 1,4-dioxane, produced
worse results (Table 1, entries 1–11). With ultradry EtOAc, the product
yield changed insignificantly, indicating that a small amount of water in
the solvent slightly effected the yield (Table 1, entry 12). Then, catalysts
or ligands were added to promote the reaction. When NiCl2 catalyst was
added, the yield was improved to 43% (Table 1, entry 13). Then, ligands
were added to the reaction (Table 1, entries 14–26), and the results
* Corresponding author: Dr Xianjin Yang, East China University of Science and Technology, China. E-mail:
E-mail address: yxj@ecust.edu.cn (X. Yang).
https://doi.org/10.1016/j.jfluchem.2021.109823
Received 15 March 2021; Received in revised form 31 May 2021; Accepted 31 May 2021
Available online 9 June 2021
0022-1139/© 2021 Elsevier B.V. All rights reserved.

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
showed that L10 (Bpy) was the optimal ligand with a yield of 52%. The
next step was to further screen different catalysts, such as NiBr2, Ni
(COD)2, Pd(OAc)2, and copper catalysts (Table 1, entries 27–34), but the
yield of the product did not improve.
3aq).
At the same time, we also studied the reactivity of aromatic het-
erocyclic olefins and functionalized styrene (α-methylstyrene); however,
the corresponding difluoroaminosulfonylated products could not be
obtained. We discovered that the expected product of 2-vinylpyridine
underwent the elimination of HF to provide imide 4, and the expected
The temperature screening showed that the reaction did not occur at
◦
room temperature, and 120 C was the optimal reaction temperature
(Table 1, entries 35–37). To make Ni(II) catalyst better participate in the
reaction, reductants were added to convert Ni(II) into Ni(0). The results
showed that Mn was the optimal reductant affording 61% yield (Table 1,
entries 38–41). In the absence of Ni(II) catalyst, when only Mn was
added, the yield was 39% (Table 1, entry 42). These results showed that
the addition of Ni(II) catalyst and Mn was necessary. Then, the reaction
time screening revealed that the product yields slightly differed for 10 h,
12 h, and 14 h; Therefore, 12 h was selected as the optimal reaction time
(Table 1, entries 43–46). Next, the amount of the catalyst, ligand, and
reductant was also screened, and the results indicated that the optimal
quantities were as follows: NiCl2 (10 mol%), L10 (5 mol%) and Mn (2.0
eq.) (Table 1, entry 47).
product of α-methylstyrene hydrolyzed to afford the compound 5, whose
structure was further confirmed by X-ray crystallography (Fig. 2). These
results indicated that the N–F bond in the products was reactive and
could be further converted to other chemical bonds.
Several control experiments were carried out to explore the reaction
mechanism, since the reaction proceeded under high temperature con-
ditions, which was speculated that it could be a free radical reaction. At
first, in the presence of 2.0 eq. TEMPO (a radical inhibitor), the reaction
of 1a and styrene afforded a trace amount of the target compound 3a, no
matter whether using our standard conditions or pure solvent conditions
with heating (Scheme 2a). Moreover, when BHT (2.0 eq.) was used
instead of TEMPO, the same result was achieved (Scheme 2b). When we
added 1,1-diphenylethylene (2.0 eq.), a free radical inhibitor, to the
reaction system, we were able to obtain 20% of compound 6 (Scheme
2c). These results indicated that the reaction might be a free radical
process. Therefore, 1a and allylbenzene were used as model substrates
to study the order of the free radical mechanism of the reaction. Then the
alkene coupling product 7 was obtained (Scheme 2d), which indicated
that the benzenesulfonyl radical first reacted with the alkene.
With the optimized reaction conditions in hand, the scope of this
reaction was evaluated (Table 2). Difluoroaminosulfonylation of styrene
with differently substituted DFBSAs provided products 3a–3e regiose-
lectively in moderate yields (41–61%). For methyl substituted styrenes,
the effect of 4-CH3 styrenes (3f–3i) was better than that of 3-CH3 sty-
renes (3j and 3k). For halide substituted styrenes, the products (3l–3x)
from o-, m-, and p-fluorostyrenes were obtained in 28–51% yields;
electronic effect did not affect the reactivity. Differently, the yields of
products provided from o- and p-chlorostyrenes (3y–3aa, 3ad, 3ae)
were higher than those of m-chlorostyrenes (3ab, 3ac). However, the
effect of bromine substituted styrenes (3af–3ai) was not as good as that
of chlorine and fluorine substituted olefins. For different substituents
(hydrogen, methyl, and halogen) of p-substituted styrenes, the yields of
the products had a small difference. However, for the same substituents,
the effect of o- and p-substituted styrenes was better than that of m-
substituted styrenes. When the substrates were p-tert-butylstyrene and
2-naphthalene ethylene, the corresponding products (3aj, 3ak) were
obtained in 25% and 21% yields, respectively. Subsequently, ether,
ester, amide, and cyano substituted styrenes (3al–3ao) were evaluated;
ether and ester substituted styrenes afforded products. Then, the
difluoroaminosulfonylation of DFBSA with nonterminal alkenes was
studied, but the corresponding product could not be obtained (3ap,
The proposed mechanism of this reaction is shown in Scheme 3. In
path A, the oxidative addition of DFBSA (1a) to Ni(0) A led to the for-
mation of the Ni(II) complex B. Compound B tautomerized to form the
Ni(I) compound C and a benzenesulfonyl radical, which then reacted
with styrene (2a) to undergo a free radical addition to obtain the free
radical intermediate D. Intermediate D continued to react with the Ni(I)
compound C to obtain the Ni(II) complex E, which finally underwent
reductive elimination to obtain the final product 3a and the recycled Ni
(0) catalyst. During our experiments, we found that the reaction could
also proceed without the addition of a catalyst and ligand. We specu-
lated that the reaction could also be triggered by heat, so we proposed
another possible reaction mechanism. In path B, 1a was cleaved by
thermal initiation to generate a benzenesulfonyl radical and a
difluoroamine radical. The benzenesulfonyl radical then reacted with
styrene to obtain the free radical intermediate D, which reacted with
Fig. 1. Examples of active pharmaceutical compounds containing amine and sulfone units.
2

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
Table 1
Optimization of the Reaction Conditions.a
Entry
Solvent
Catalyst
Ligand b
T (◦C)
Time (h)
Yield (%) c
1
DMF
-
-
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
120
100
60
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
14
10
8
18
14
<5
Trace
29
34
29
35
31
35
5
2
PhCH3
CH3SOCH3
CH3OH
1,4-Dioxane
CH3CN
THF
-
-
3
-
-
4
-
-
5
-
-
6
-
-
7
-
-
8
EtOAc
DCE
-
-
9
-
-
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
47f
Butyronitrile
HFIP
-
-
-
-
EtOAc d
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
EtOAc
-
-
37
43
37
43
47
37
18
38
48
42
38
52
41
43
39
35
20
47
44
46
Trace
16
20
34
Trace
N. R.
43
28
40
61
39
58
56
52
26
61
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiCl2
NiBr2
NiI2
-
L1
L2
L3
L4
L5
L6
L7
L8
L9
L10
L11
L12
L13
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
L10
Ni(COD)2
Ni(Cp)2
Ni(allyl)(Cp)
Cu e
PdCl2
Pd(OAc)2
NiCl2
NiCl2
NiCl2
NiCl2-Zn
NiCl2-Fe
NiCl2-Mg
NiCl2-Mn
Mn
r.t.
120
120
120
120
120
120
120
120
120
120
NiCl2-Mn
NiCl2-Mn
NiCl2-Mn
NiCl2-Mn
NiCl2-Mn
6
12
a
The reaction was carried out with styrene (2a, 0.8 mmol), catalyst (10 mol%), ligand (5 mol%), DFBSA (1a, 1.2 eq.), reductant (2 eq.) in solvent at 120 ◦C under air.
b
Ligands only.
c
Isolated yield.
d
Ultradry EtOAc.
e
Cu catalysts including Cu, CuCl, CuCl2, Cu(OAc)2, Cu2O.
f
Equivalent screening for NiCl2 (10 mol%, 15 mol%, 20 mol%), L10 (5 mol%, 7.5 mol%) and Mn (10 mol%, 0.8 eq., 1.2 eq., 1.5 eq., 2.0 eq., 3.0 eq.) and the optimal
equivalents were NiCl2 (10 mol%), L10 (5 mol%) and Mn (2.0 eq.).
3

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
Table 2
Substrate Scope of Alkenes a,b
a
Reaction conditions: alkene (0.8 mmol), DFBSA (1.2 eq.), NiCl2 (10 mol%), Bpy (5 mol %), Mn (2 eq.) in 4.0 mL of EtOAc at 120 ◦C oil bath for 12 h under air.
Isolated yield.
b
4

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
Fig. 2. X-ray crystal structure of 5.
Scheme 1. The synthesis of DFBSAs
Scheme 2. Control experiments
DFBSA to obtain the final product 3a.
3. Conclusion
The moderate yields might have been attributed to the instability of
the product itself. Therefore, we studied the reactivity of the N–F bond of
the product using 3a as a model substrate (Scheme 4). In the presence of
pyridine, HF was easily eliminated from 3a to form compound 8 and the
hydrolyzed product 9. Interestingly, 3a was found to be stable in wet
solvents at room temperature, but 3a underwent hydrolysis in the
presence of water in EtOAc at higher temperature (85 ◦C) to obtain
compound 9.
In summary, we developed a new method to synthesize DFBSAs,
which were then used as reagents for the nickel-catalyzed amino-
sulfonylation of alkenes to provide the corresponding N,N-difluor-
oaminosulfonylated products. For most alkenes used in this study, the
reaction produced moderate yields and demonstrated excellent regio-
selectivity. Preliminary mechanistic studies indicated that the reaction
was free radical-promoted, with DFBSA being a benzenesulfonyl radical
precursor. Overall, the incorporation of N,N-difluoroaminosulfonyl
functional groups into small molecules, such as drug pharmacophores,
5

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
Scheme 3. Proposed mechanism.
Scheme 4. Gram reaction scale and the reactivity of N–F bond of aminosulfonylated products.
may manifest promising biological (i.e. physicochemical) properties.
Moreover, these N,N-difluoroaminosulfones can serve as intermediates
to undergo further conversion to other functional groups using estab-
lished or novel methodologies.
acetamide [13]. N-Fluorobenzenesulfonamide and its derivatives were
purchased from Aldrich or Shanghai Science Bio-pharmaceutical Co.
Ltd. Flash column chromatography was used on silica gel (300–400
mesh). NMR spectra were recorded on a Bruker AM-400 (400 MHz for
1H; 101 MHz or 151 MHz for 13C; 376 MHz for 19F which is decoupled
with 1H) spectrometer. Chemical shifts (δ value) were reported in ppm
down field from internal tetramethylsilane (TMS). IR spectra (Film)
were recorded on a Nicolet 6700 spectrophotometer in the range of
400–4000 cmꢀ 1. HRMS (EI) Mass spectra were recorded on a Waters
GCT Premier mass spectrometer with electron impact.
4. Experimental section
4.1. General information
All the starting chemicals were commercially available and used as
received without further purification, except N-(4-vinylphenyl)
6

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
4.2. Preparation of the substrates DFBSA
129.00, 128.02, 73.86, 55.53; IR (KBr, cmꢀ 1):
ν 3063, 2989, 2922, 1584,
1495, 1452, 1409, 1332, 1306, 1148, 1084; HRMS-EI (m/z) calcd. for
(C14H13NO2F2S-F2) 259.0667, found 259.0664.
Take 1a as an example: N-fluorobenzene sulfonamide (1.75 g, 0.01
mol, 1.0 eq.) in acetone (20 mL), and NaOH (0.48 g, 0.012 mol, 1.2 eq.)
were added several times in small amounts, and the reaction mixture
was stirred for 0.5 h. Then, Selectfluor (4.2 g, 0.012 mol, 1.2 eq.) was
added in two portions, and the reaction mixture was stirred at 0 ◦C for 4
h. Then, the solvent was removed under reduced pressure, and the
residue was purified by flash chromatography on silica gel (eluent: PE/
EA=50:1 v/v). A conventional method to prepare the DFBSA derivatives
1b, 1c, 1d, and 1e.
4.3.2. N,N-difluoro-1-phenyl-2-tosylethan-1-amine (3b)
A yellow solid; m.p.: 70.7–71.9 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.49
(d, J = 8.3 Hz, 2H), 7.26 (t, J = 7.2 Hz, 1H), 7.20 (t, J = 7.3 Hz, 2H), 7.12
(dd, J = 12.2, 7.7 Hz, 4H), 4.93 (tdd, J = 26.1, 9.2, 4.6 Hz, 1H), 3.92 (dd,
J = 14.6, 3.5 Hz, 1H), 3.75 (dd, J = 14.6, 9.2 Hz, 1H), 2.30 (s, 3H); 19
F
NMR (376 MHz, CDCl3) δ 45.38 (d, J = 579.0 Hz, 1F), 41.92 (d, J =
575.3 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 145.16, 136.04, 130.73 (t,
J = 6.0 Hz), 129.92, 129.87, 129.68, 128.92, 128.04, 73.84, 55.57,
4.2.1. N,N-difluorobenzenesulfonamide (1a)
21.73; IR (KBr, cmꢀ 1):
ν 3035, 2991, 2935, 1595, 1494, 1458, 1415,
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 8.07 (d, J = 7.5 Hz,
2H), 7.90 (t, J = 7.5 Hz, 1H), 7.71 (t, J = 7.9 Hz, 2H); 19F NMR (376
MHz, CDCl3) δ 40.40 (s); 13C NMR (101 MHz, CDCl3) δ 137.38, 132.08,
1328, 1300, 1142, 1084; HRMS-EI (m/z) calcd. for (C15H15NO2F2S-F2)
273.0824, found 273.0819.
129.97, 127.90; IR (ATR, cmꢀ 1):
ν
3074, 1581, 1450, 1392, 1189, 1083;
4.3.3. N,N-difluoro-2-((4-fluorophenyl)sulfonyl)-1-phenylethan-1-amine
(3c)
HRMS-EI (m/z) calcd. for (C6H5SO2NF2-NF2) 141.0010, found 141.0012.
A yellow solid; m.p.: 95.6–96.0 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.66
(dd, J = 8.7, 5.0 Hz, 2H), 7.35 (t, J = 7.3 Hz, 1H), 7.28 (t, J = 7.7 Hz,
2H), 7.21 (d, J = 7.4 Hz, 2H), 7.04 (t, J = 8.5 Hz, 2H), 5.12–4.95 (m,
4.2.2. N,N-difluoro-4-methylbenzenesulfonamide (1b)
A brown liquid; 1H NMR (400 MHz, CDCl3) δ 7.94 (d, J = 8.3 Hz,
2H), 7.49 (d, J = 8.1 Hz, 2H), 2.53 (s, 3H); 19F NMR (376 MHz, CDCl3) δ
40.36 (s); 13C NMR (151 MHz, CDCl3) δ 149.42, 132.12, 130.67, 124.65,
1H), 4.04 (dd, J = 14.7, 3.5 Hz, 1H), 3.86 (dd, J = 14.7, 9.4 Hz, 1H); 19
F
NMR (376 MHz, CDCl3) δ 45.26 (d, J = 575.3 Hz, 1F), 41.91 (d, J =
579.0 Hz, 1F), -102.66 (s, 1F); 13C NMR (101 MHz, CDCl3) δ 165.89 (d, J
= 257.3 Hz), 135.11 (d, J = 3.3 Hz), 131.02, 130.97 (d, J = 9.7 Hz),
130.38 (t, J = 6.1 Hz), 129.72, 129.05, 116.60 (d, J = 22.8 Hz), 73.90,
22.20; IR (ATR, cmꢀ 1):
ν 3068, 1593, 1392, 1305, 1176, 1084; HRMS-EI
(m/z) calcd. for (C7H7SO2NF2-NF2) 155.0167, found 155.0169.
4.2.3. N,N,4-trifluorobenzenesulfonamide (1c)
55.62; IR (KBr, cmꢀ 1):
ν 3070, 2960, 1590, 1492, 1406, 1312, 1292,
A brown liquid; 1H NMR (400 MHz, CDCl3) δ 8.11 (dd, J = 8.8, 4.9
Hz, 2H), 7.39 (t, J = 8.4 Hz, 2H); 19F NMR (376 MHz, CDCl3) δ 40.99 (s,
2F), -96.03 (s, 1F); 13C NMR (101 MHz, CDCl3) δ 168.33 (d, J = 262.9
Hz), 135.31 (d, J = 10.6 Hz), 123.62, 117.74 (d, J = 23.1 Hz); IR (ATR,
1225, 1146, 1084; HRMS-EI (m/z) calcd. for (C14H12NO2F3S-F2)
277.0573, found 277.0576.
4.3.4. 2-((4-chlorophenyl)sulfonyl)-N,N-difluoro-1-phenylethan-1-amine
(3d)
cmꢀ 1):
ν 3110, 1587, 1492, 1396, 1299, 1247, 1188, 1156, 1084;
HRMS-EI (m/z) calcd. for (C6H4SO2NF3-NF2) 158.9916, found 158.9920.
A yellow solid; m.p.: 83.7–86.4 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.64
(d, J = 8.5 Hz, 2H), 7.41 (t, J = 7.0 Hz, 3H), 7.35 (t, J = 7.5 Hz, 2H), 7.27
(d, J = 7.5 Hz, 2H), 5.09 (tdd, J = 25.9, 9.4, 4.7 Hz, 1H), 4.11 (dd, J =
14.7, 3.5 Hz, 1H), 3.93 (dd, J = 14.7, 9.4 Hz, 1H); 19F NMR (376 MHz,
4.2.4. 4-chloro-N,N-difluorobenzenesulfonamide (1d)
A white solid; m.p.: 59.2–59.8 ◦C; 1H NMR (400 MHz, CDCl3) δ 8.00
(d, J = 8.7 Hz, 2H), 7.69 (d, J = 8.7 Hz, 2H); 19F NMR (376 MHz, CDCl3)
δ 41.03 (s); 13C NMR (101 MHz, CDCl3) δ 144.95, 133.39, 130.50,
CDCl3) δ 45.35 (d, J = 575.3 Hz, 1F), 41.92 (d, J = 575.3 Hz, 1F); 13
C
NMR (151 MHz, CDCl3) δ 140.90, 137.54, 130.38 (t, J = 5.4 Hz),
126.18; IR (ATR, cmꢀ 1):
ν
3068, 1593, 1392, 1305, 1176, 1084; HRMS-
130.16, 129.76, 129.61, 129.52, 129.10, 73.81, 55.64; IR (KBr, cmꢀ 1):
ν
EI (m/z) calcd. for (C6H4ClSO2NF2-NF2) 174.9612, found 174.9617.
3064, 2993, 2943, 1639, 1580, 1475, 1402, 1334, 1306, 1143, 1087;
HRMS-EI (m/z) calcd. for (C14H12NO2F2SCl-F2) 293.0277, found
293.0273.
4.2.5. N,N-difluoro-4-nitrobenzenesulfonamide (1e)
A yellow solid; m.p.: 63.1–63.7 ◦C; 1H NMR (400 MHz, CDCl3) δ 8.54
(d, J = 9.0 Hz, 2H), 8.30 (d, J = 8.9 Hz, 2H); 19F NMR (376 MHz, CDCl3)
δ 41.71 (s);13C NMR (101 MHz, CDCl3) δ 152.88, 133.65, 133.42,
4.3.5. N,N-difluoro-2-((4-nitrophenyl)sulfonyl)-1-phenylethan-1-amine
(3e)
124.96; IR (KBr, cmꢀ 1):
ν
3116, 1610,1537, 1408, 1351, 1314, 1215,
A yellow solid; m.p.: 121.1–122.4 ◦C; 1H NMR (400 MHz, CDCl3) δ
8.18 (d, J = 8.8 Hz, 2H), 7.80 (d, J = 8.8 Hz, 2H), 7.34 (t, J = 7.3 Hz,
1H), 7.28–7.23 (m, 2H), 7.19 (d, J = 7.5 Hz, 2H), 5.06 (tdd, J = 25.6,
9.4, 4.7 Hz, 1H), 4.11 (dd, J = 14.9, 3.8 Hz, 1H), 3.92 (dd, J = 14.9, 9.5
Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.28 (d, J = 579.0 Hz, 1F), 42.00
(d, J = 579.0 Hz, 1F); 13C NMR (151 MHz, CDCl3) δ 150.76, 144.58,
130.42, 129.99 (t, J = 5.4 Hz), 129.81, 129.54, 129.17, 124.30, 73.74,
55.68; HRMS-EI (m/z) calcd. for (C14H12N2O4F2S-F2) 304.0518, found
304.0512.
1195, 1083; HRMS-EI (m/z) calcd. for (C6H4SO4N2F2-NF2) 185.9861,
found 185.9860.
4.3. General Procedures
Styrene (0.8 mmol), DFBSA (1.2 eq.), NiCl2 (10 mol%), Bpy (5 mol
%), and Mn (2 eq.) in 4.0 mL ethyl acetate were added to a sealed tube
equipped with a magnetic stir bar. The reaction mixture was stirred at
120 ◦C on oil bath for 12 h. Then, the reaction mixture was purified by
silica gel chromatography (eluent: PE/EA=20:1 v/v) to afford the
products.
4.3.6. N,N-difluoro-2-(phenylsulfonyl)-1-(P-tolyl)ethan-1-amine (3f)
A white solid; m.p.: 96.7–97.2 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.68
(d, J = 7.3 Hz, 2H), 7.56 (t, J = 7.5 Hz, 1H), 7.41 (t, J = 7.8 Hz, 2H), 7.09
(q, J = 8.2 Hz, 4H), 5.00 (tdd, J = 26.1, 9.3, 3.5 Hz, 1H), 4.01 (dd, J =
14.6, 3.6 Hz, 1H), 3.84 (dd, J = 14.6, 9.4 Hz, 1H), 2.31 (s, 3H); 19F NMR
(376 MHz, CDCl3) δ 45.36 (d, J = 575.3 Hz, 1F), 41.68 (d, J = 575.3 Hz,
1F); 13C NMR (151 MHz, CDCl3) δ 140.18, 139.19, 133.89, 129.68,
129.59, 129.28, 128.06, 127.57 (t, J = 5.6 Hz), 73.59, 55.57, 21.33; IR
4.3.1. N,N-difluoro-1-phenyl-2-(phenylsulfonyl)ethan-1-amine (3a)
A white solid; m.p.: 89.8–91.1 ◦C; 1H NMR (400 MHz, CDCl3) δ
7.71–7.66 (m, 2H), 7.55 (t, J = 7.5 Hz, 1H), 7.40 (t, J = 7.8 Hz, 2H), 7.33
(t, J = 7.1 Hz, 1H), 7.30–7.25 (m, 2H), 7.22 (d, J = 7.3 Hz, 2H), 5.04
(dddd, J = 26.1, 23.0, 9.3, 3.5 Hz, 1H), 4.03 (dd, J = 14.7, 3.5 Hz, 1H),
3.86 (dd, J = 14.6, 9.3 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 42.51 (d, J
= 579.0 Hz, 1F), 41.87 (d, J = 575.3 Hz, 1F); 13C NMR (151 MHz, CDCl3)
δ 139.11, 134.04, 130.63 (t, J = 5.6 Hz), 130.06, 129.68, 129.34,
(KBr, cmꢀ 1):
ν 3035, 2986, 2941, 1633, 1516, 1447, 1422, 1329, 1302,
1142, 1084; HRMS-EI (m/z) calcd. for (C15H15NO2F2S-F2) 273.0824,
found 273.0827.
7

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
4.3.7. N,N-difluoro-1-(p-tolyl)-2-tosylethan-1-amine (3g)
Hz, 1H), 7.00 (t, J = 9.3 Hz, 1H), 5.33 (tdd, J = 24.1, 9.2, 3.8 Hz, 1H),
4.01 (dd, J = 14.7, 3.9 Hz, 1H), 3.94 (dd, J = 14.7, 9.2 Hz, 1H); 19F NMR
(376 MHz, CDCl3) δ 44.97 (d, J = 582.8 Hz, 1F), 43.91 (d, J = 579.0 Hz,
1F), -114.58 (s, 1F); 13C NMR (151 MHz, CDCl3) δ 161.34 (d, J = 251.1
Hz), 138.68, 134.21, 132.13 (d, J = 8.5 Hz), 130.89, 129.41, 128.05,
124.62, 117.87 (dt, J = 12.3, 6.0 Hz), 116.23 (d, J = 22.2 Hz), 67.72,
1
◦
A white solid; m.p.: 106.7–107.1 C; H NMR (400 MHz, CDCl3) δ
7.56 (d, J = 8.3 Hz, 2H), 7.19 (d, J = 8.0 Hz, 2H), 7.13–7.05 (m, 4H),
4.96 (tdd, J = 26.1, 9.3, 4.7 Hz, 1H), 3.98 (dd, J = 14.6, 3.5 Hz, 1H),
3.81 (dd, J = 14.5, 9.3 Hz, 1H), 2.40 (s, 3H), 2.32 (s, 3H); 19F NMR (376
MHz, CDCl3) δ 45.21 (d, J = 575.3 Hz, 1F), 41.72 (d, J = 575.3 Hz, 1F);
13C NMR (151 MHz, CDCl3) δ 145.09, 140.09, 136.19, 129.88, 129.61,
128.66, 128.09, 127.71 (t, J = 5.4 Hz), 73.64, 55.60, 21.71, 21.32; IR
54.50; IR (KBr, cmꢀ 1):
ν 3067, 2922, 1618, 1587, 1495, 1454, 1311,
1238, 1149, 1086; HRMS-EI (m/z) calcd. for (C14H12NO2F3S-F2)
277.0573, found 277.0569.
(KBr, cmꢀ 1):
ν 3083, 2988, 2938, 1622, 1598, 1515, 1422, 1328, 1301,
1141, 1086; HRMS-EI (m/z) calcd. for (C16H17NO2F2S-F2) 291.0980,
found 291.0985.
4.3.13. N,N-difluoro-1-(2-fluorophenyl)-2-tosylethan-1-amine (3m)
A colorless solid; m.p.: 47.3–48.8 ◦C; 1H NMR (400 MHz, CDCl3) δ
7.61 (d, J = 8.1 Hz, 2H), 7.33 (q, J = 7.3 Hz, 1H), 7.21 (d, J = 7.8 Hz,
3H), 7.07 (t, J = 7.6 Hz, 1H), 6.99 (t, J = 9.3 Hz, 1H), 5.31 (tdd, J = 24.2,
9.2, 3.7 Hz, 1H), 3.98 (dd, J = 14.7, 3.9 Hz, 1H), 3.90 (dd, J = 14.6, 9.2
Hz, 1H), 2.38 (s, 3H); 19F NMR (376 MHz, CDCl3) δ 44.79 (d, J = 582.8
Hz, 1F), 43.95 (d, J = 582.8 Hz, 1F), -114.64 (s, 1F); 13C NMR (101 MHz,
CDCl3) δ 161.32 (d, J = 250.8 Hz), 145.36, 135.64, 131.91 (d, J = 8.7
Hz), 130.88, 129.98, 128.07, 124.57 (d, J = 3.4 Hz), 117.99 (dt, J =
12.7, 6.4 Hz), 116.14 (d, J = 22.3 Hz), 67.71, 54.59, 21.71; IR (KBr,
4.3.8. N,N-difluoro-2-((4-fluorophenyl)sulfonyl)-1-(p-tolyl)ethan-1-amine
(3h)
A white solid; m.p.: 93.2–93.9 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.66
(dd, J = 8.9, 5.0 Hz, 2H), 7.06 (d, J = 13.6 Hz, 6H), 4.98 (dddd, J = 26.0,
23.0, 9.6, 3.8 Hz, 1H), 4.01 (dd, J = 14.7, 3.6 Hz, 1H), 3.84 (dd, J =
14.7, 9.5 Hz, 1H), 2.33 (s, 3H); 19F NMR (376 MHz, CDCl3) δ 45.12 (d, J
= 579.0 Hz, 1F), 41.65 (d, J = 575.3 Hz, 1F), -102.87 (s, 1F); 13C NMR
(151 MHz, CDCl3) δ 165.93 (d, J = 256.8 Hz), 140.39, 135.22 (d, J = 2.7
Hz), 131.01 (d, J = 9.7 Hz), 129.68 (d, J = 11.0 Hz), 127.34 (t, J = 5.8
cmꢀ 1):
ν 3060, 2988, 2931, 1594, 1495, 1457, 1331, 1237, 1145, 1089;
Hz), 116.60, 116.45, 73.65, 55.63, 21.30; IR (KBr, cmꢀ 1):
ν
3102, 2984,
HRMS-EI (m/z) calcd. for (C15H14NO2F3S-F2) 291.0729, found
2937, 1590, 1492, 1330, 1306, 1141, 1083; HRMS-EI (m/z) calcd. for
(C15H14NO2F3S-F2) 291.0729, found 291.0733.
291.0728.
4.3.14. N,N-difluoro-1-(4-fluorophenyl)-2-((4-fluorophenyl)sulfonyl)
ethan-1-amine (3n)
4.3.9. 2-((4-chlorophenyl)sulfonyl)-N,N-difluoro-1-(p-tolyl)ethan-1-
amine (3i)
A yellow solid; m.p.: 60.2–62.7 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.73
(dd, J = 8.7, 5.0 Hz, 2H), 7.34 (q, J = 6.2, 5.7 Hz, 1H), 7.21 (t, J = 7.1
Hz, 1H), 7.08 (t, J = 8.4 Hz, 3H), 7.00 (t, J = 9.3 Hz, 1H), 5.32 (tdd, J =
24.0, 9.1, 3.7 Hz, 1H), 4.01 (dd, J = 14.8, 3.9 Hz, 1H), 3.94 (dd, J =
14.8, 9.3 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 44.71 (d, J = 586.6 Hz,
1F), 43.99 (d, J = 582.8 Hz, 1F), -102.37 (s, 1F), -114.52 (s, 1F); 13C
NMR (151 MHz, CDCl3) δ 166.02 (d, J = 257.2 Hz), 161.29 (d, J = 251.0
Hz), 134.69, 132.22 (d, J = 9.2 Hz), 131.03 (d, J = 9.9 Hz), 130.91,
124.70 (d, J = 3.8 Hz), 117.98–117.56 (m), 116.69 (d, J = 23.2 Hz),
116.25 (d, J = 22.0 Hz), 67.74, 54.64; HRMS-EI (m/z) calcd. for
(C14H11NO2F4S-F2) 295.0479, found 295.0478.
1
◦
A white solid; m.p.: 106.5–108.4 C; H NMR (400 MHz, CDCl3) δ
7.55 (d, J = 7.5 Hz, 2H), 7.32 (d, J = 7.5 Hz, 2H), 7.06 (s, 4H), 4.97 (td,
J = 24.7, 9.4 Hz, 1H), 4.01 (d, J = 14.6 Hz, 1H), 3.89–3.80 (m, 1H), 2.33
(s, 3H); 19F NMR (376 MHz, CDCl3) δ 45.25 (d, J = 575.3 Hz, 1F), 41.66
(d, J = 575.3 Hz, 1F); 13C NMR (151 MHz, CDCl3) δ 140.73, 140.47,
137.52, 129.69, 129.64, 129.52, 129.46, 127.15 (t, J = 5.4 Hz), 73.63,
55.52, 21.29; IR (KBr, cmꢀ 1):
ν 3092, 3033, 2992, 2944, 1580, 1516,
1419, 1395, 1335, 1310, 1280, 1144, 1089; HRMS-EI (m/z) calcd. for
(C15H14NO2F2SCl-F2) 307.0434, found 307.0439.
4.3.10. N,N-difluoro-2-(phenylsulfonyl)-1-(m-tolyl)ethan-1-amine (3j)
A yellow solid; m.p.: 54.1–56.4 ◦C; 1H NMR (400 MHz, CDCl3) δ
7.60–7.54 (m, 2H), 7.43 (t, J = 7.5 Hz, 1H), 7.28 (t, J = 7.8 Hz, 2H), 7.05
(t, J = 7.5 Hz, 1H), 7.01 (d, J = 7.6 Hz, 1H), 6.93 (d, J = 7.4 Hz, 1H),
6.85 (s, 1H), 4.89 (tdd, J = 22.8, 9.3, 4.6 Hz, 1H), 3.92 (dd, J = 14.7, 3.5
Hz, 1H), 3.77 (dd, J = 14.7, 9.3 Hz, 1H), 2.14 (s, 3H); 19F NMR (376
MHz, CDCl3) δ 45.91 (d, J = 575.3 Hz, 1F), 42.03 (d, J = 575.3 Hz, 1F);
13C NMR (151 MHz, CDCl3) δ 139.01, 138.68, 133.90, 130.75, 130.35 (t,
J = 5.2 Hz), 130.15, 129.13, 128.83, 127.92, 126.79, 73.86, 55.34,
4.3.15. 2-((4-chlorophenyl)sulfonyl)-N,N-difluoro-1-(2-fluorophenyl)
ethan-1-amine (3o)
A white solid; m.p.: 72.4–72.9 ◦C; 1H NMR (400 MHz, CDCl3) δ
7.68–7.51 (m, 2H), 7.37 (d, J = 7.2 Hz, 3H), 7.19 (t, J = 7.2 Hz, 1H),
7.08 (t, J = 7.4 Hz, 1H), 6.99 (t, J = 9.2 Hz, 1H), 5.31 (td, J = 23.8, 8.5
Hz, 1H), 4.00 (d, J = 13.4 Hz, 1H), 3.97–3.90 (m, 1H); 19F NMR (376
MHz, CDCl3) δ 44.91 (d, J = 582.8 Hz, 1F), 44.01 (d, J = 579.0 Hz, 1F),
-114.34 (s, 1F); 13C NMR (151 MHz, CDCl3) δ 161.32 (d, J = 251.1 Hz),
141.10, 137.10, 132.68, 132.23 (d, J = 9.0 Hz), 130.97 (d, J = 2.3 Hz),
129.63 (d, J = 17.8 Hz), 124.74 (d, J = 3.7 Hz), 117.73 (dt, J = 12.2, 6.0
21.26; IR (ATR, cmꢀ 1):
ν 3037, 2927, 2956, 1448, 1307, 1146, 1088;
HRMS-EI (m/z) calcd. for (C15H15NO2F2S-F2) 273.0824, found
273.0825.
Hz), 116.32 (d, J = 22.2 Hz), 67.80, 54.65; IR (KBr, cmꢀ 1):
ν 3096, 2992,
2935, 1617, 1579, 1493, 1458, 1416, 1314, 1282, 1178, 1150, 1086;
HRMS-EI (m/z) calcd. for (C14H11NO2F3SCl-F2) 311.0183, found
311.0185.
4.3.11. N,N-difluoro-1-(m-tolyl)-2-tosylethan-1-amine (3k)
A yellow solid; m.p.: 71.4–73.0 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.54
(d, J = 8.3 Hz, 2H), 7.15 (dd, J = 14.8, 7.7 Hz, 4H), 7.03 (d, J = 7.4 Hz,
1H), 6.93 (s, 1H), 4.96 (tdd, J = 26.2, 9.3, 3.4 Hz, 1H), 3.99 (dd, J =
14.6, 3.5 Hz, 1H), 3.83 (dd, J = 14.6, 9.3 Hz, 1H), 2.38 (s, 3H), 2.24 (s,
3H); 19F NMR (376 MHz, CDCl3) δ 45.76 (d, J = 575.3 Hz, 1F), 41.97 (d,
J = 575.3 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 145.02, 138.64, 136.07,
130.59, 130.47 (d, J = 5.7 Hz), 130.18 (d, J = 3.1 Hz), 129.78, 128.83,
128.02, 126.88, 73.95, 55.49, 21.68, 21.31; HRMS-EI (m/z) calcd. for
(C16H17NO2F2S-F2) 291.0980, found 291.0976.
4.3.16. N,N-difluoro-1-(2-fluorophenyl)-2-((4-nitrophenyl)sulfonyl)
ethan-1-amine (3p)
A yellow solid; m.p.: 127.2–127.8 ◦C; 1H NMR (400 MHz, CDCl3) δ
8.24 (d, J = 8.8 Hz, 2H), 7.91 (d, J = 8.8 Hz, 2H), 7.40–7.31 (m, 1H),
7.21 (t, J = 6.7 Hz, 1H), 7.08 (t, J = 7.5 Hz, 1H), 7.01 –6.95 (m, 1H),
5.43–5.25 (m, 1H), 4.09 (dd, J = 15.0, 4.1 Hz, 1H), 4.00 (dd, J = 14.9,
9.2 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 44.89 (d, J = 579.0 Hz, 1F),
44.09 (d, J = 582.8 Hz, 1F), -114.09 (s, 1F); 13C NMR (151 MHz, CDCl3)
δ 161.30 (d, J = 252.0 Hz), 150.98, 144.22, 132.56 (d, J = 8.9 Hz),
131.07 (d, J = 2.3 Hz), 129.65, 124.85 (d, J = 3.9 Hz), 124.43,
117.78–117.33 (m), 116.38 (d, J = 22.0 Hz), 67.80, 54.68; IR (KBr,
4.3.12. N,N-difluoro-1-(2-fluorophenyl)-2-(phenylsulfonyl)ethan-1-amine
(3l)
A white solid; m.p.: 63.8–66.4 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.74
(d, J = 7.3 Hz, 2H), 7.57 (t, J = 7.5 Hz, 1H), 7.44 (t, J = 7.8 Hz, 2H), 7.33
(ddd, J = 15.4, 5.3, 1.7 Hz, 1H), 7.22 (t, J = 6.8 Hz, 1H), 7.07 (t, J = 7.6
cmꢀ 1):
ν 3100, 2946, 1610, 1529, 1493, 1350, 1305, 1149, 1086;
HRMS-EI (m/z) calcd. for (C14H11N2O4F3S-F2) 322.0424, found
8

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
322.0420.
Hz), 139.09, 134.18, 131.67 (d, J = 8.4 Hz), 129.43, 128.02, 126.45,
116.13 (d, J = 21.6 Hz), 73.07, 55.51; IR (KBr, cmꢀ 1):
ν 3080, 2920,
4.3.17. N,N-difluoro-1-(3-fluorophenyl)-2-(phenylsulfonyl)ethan-1-amine
(3q)
1606, 1514, 1447, 1409, 1329, 1305, 1236, 1146, 1084; HRMS-EI (m/z)
calcd. for (C14H12NO2F3S-F2) 277.0573, found 277.0575.
A white solid; m.p.: 71.2–72.4 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.71
(d, J = 7.3 Hz, 2H), 7.58 (t, J = 7.5 Hz, 1H), 7.44 (t, J = 7.8 Hz, 2H),
7.31–7.24 (m, 1H), 7.08–7.01 (m, 2H), 6.91 (d, J = 9.3 Hz, 1H),
5.12–4.95 (m, 1H), 4.00 (dd, J = 14.7, 3.4 Hz, 1H), 3.81 (dd, J = 14.6,
9.4 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.27 (d, J = 579.0 Hz, 1F),
42.18 (d, J = 579.0 Hz, 1F), -111.52 (s, 1F); 13C NMR (151 MHz, CDCl3)
δ 162.69 (d, J = 248.3 Hz), 138.98, 134.26, 132.87 (q, J = 6.3 Hz),
130.65 (d, J = 8.3 Hz), 129.43, 128.01, 125.58, 117.20 (d, J = 20.8 Hz),
4.3.22. N,N-difluoro-1-(4-fluorophenyl)-2-tosylethan-1-amine (3v)
A white solid; m.p.: 98.1–100.4 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.57
(d, J = 8.3 Hz, 2H), 7.22 (t, J = 7.7 Hz, 4H), 6.97 (t, J = 8.6 Hz, 2H),
5.09–4.93 (m, 1H), 3.98 (dd, J = 14.6, 3.4 Hz, 1H), 3.78 (dd, J = 14.5,
9.6 Hz, 1H), 2.41 (s, 3H); 19F NMR (376 MHz, CDCl3) δ 44.71 (d, J =
579.0 Hz, 1F), 41.75 (d, J = 579.0 Hz, 1F), -110.71 (s, 1F); 13C NMR
(151 MHz, CDCl3) δ 163.63 (d, J = 250.3 Hz), 145.41, 136.11, 131.68
(d, J = 8.7 Hz), 130.01, 128.06, 126.63–126.40 (m), 116.05 (d, J = 21.8
Hz), 73.11, 55.57, 21.71; HRMS-EI (m/z) calcd. for (C15H14NO2F3S-F2)
291.0729, found 291.0723.
116.64 (d, J = 23.2 Hz), 73.2, 55.44; IR (KBr, cmꢀ 1):
ν 3068, 2989,
2940, 1621, 1592, 1492, 1449, 1406, 1333, 1306, 1241, 1144, 1084;
HRMS-EI (m/z) calcd. for (C14H12NO2F3S-F2) 277.0573, found
277.0576.
4.3.23. N,N-difluoro-1-(4-fluorophenyl)-2-tosylethan-1-amine (3w)
A yellow solid; m.p.: 76.3–77.0 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.59
(dd, J = 24.7, 9.0 Hz, 2H), 7.41 (d, J = 7.6 Hz, 2H), 7.22 (s, 2H), 7.00 (t,
J = 8.0 Hz, 2H), 5.03 (td, J = 23.7, 8.9 Hz, 1H), 4.01 (d, J = 14.6 Hz,
1H), 3.80 (dd, J = 14.5, 9.6 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 44.55
4.3.18. N,N-difluoro-1-(3-fluorophenyl)-2-tosylethan-1-amine (3r)
A white solid; m.p.: 96.0–97.3 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.58
(d, J = 8.3 Hz, 2H), 7.31–7.21 (m, 3H), 7.08–7.01 (m, 2H), 6.89 (d, J =
9.3 Hz, 1H), 5.09–4.93 (m, 1H), 3.97 (dd, J = 14.6, 3.4 Hz, 1H), 3.77
(dd, J = 14.6, 9.4 Hz, 1H), 2.40 (s, 3H); 19F NMR (376 MHz, CDCl3) δ
45.18 (d, J = 579.0 Hz, 1F), 42.26 (d, J = 579.0 Hz, 1F), -111.71 (s, 1F);
13C NMR (151 MHz, CDCl3) δ 162.71 (d, J = 247.9 Hz), 145.48, 135.98,
133.01 (q, J = 6.3 Hz), 130.61 (d, J = 7.9 Hz), 130.04, 128.08, 125.64
(d, J = 2.7 Hz), 117.03 (d, J = 21.5 Hz), 116.65 (d, J = 22.4 Hz), 73.28,
(d, J = 579.0 Hz, 1F), 41.76 (d, J = 579.0 Hz, 1F), -110.04 (s, 1F); 13
C
NMR (101 MHz, CDCl3) δ 163.72 (d, J = 250.9 Hz), 141.13, 137.50,
132.71, 131.68 (d, J = 8.4 Hz), 129.61 (d, J = 21.4 Hz), 126.72–125.56
(m), 116.21 (d, J = 22.1 Hz), 72.91, 55.63; IR (KBr, cmꢀ 1):
ν 3086, 2937,
1603, 1578, 1512, 1474, 1398, 1319, 1226, 1148, 1089, 1011; HRMS-EI
55.57, 21.74; IR (KBr, cmꢀ 1):
ν
3068, 2992, 2944, 1593, 1492, 1453,
(m/z) calcd. for (C14H11NO2F3SCl-F2) 311.0183, found 311.0187.
1421, 1330, 1301,1248, 1142, 1085; HRMS-EI (m/z) calcd. for
(C15H14NO2F3S-F2) 291.0729, found 291.0724.
4.3.24. N,N-difluoro-1-(4-fluorophenyl)-2-((4-nitrophenyl)sulfonyl)
ethan-1-amine (3x)
4.3.19. 2-((4-chlorophenyl)sulfonyl)-N,N-difluoro-1-(3-fluorophenyl)
ethan-1-amine (3s)
A yellow solid; m.p.: 89.9–91.1 ◦C; 1H NMR (400 MHz, CDCl3) δ 8.29
(d, J = 8.7 Hz, 2H), 7.91 (d, J = 8.7 Hz, 2H), 7.27–7.23 (m, 2H), 7.01 (t,
J = 8.4 Hz, 2H), 5.09 (tdd, J = 24.1, 9.3, 4.0 Hz, 1H), 4.09 (dd, J = 14.8,
4.0 Hz, 1H), 3.86 (dd, J = 14.8, 9.1 Hz, 1H); 19F NMR (376 MHz, CDCl3)
δ 44.18 (d, J = 579.0 Hz, 1F), 41.87 (d, J = 579.0 Hz, 1F), -109.36 (s,
1F); 13C NMR (151 MHz, CDCl3) δ 163.84 (d, J = 252.3 Hz), 151.00,
144.67, 131.75, 129.61, 126.09 (q, J = 5.6 Hz), 124.51, 116.37 (d, J =
A white solid; 96.3–96.9 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.67–7.38
(m, 4H), 7.29 (dd, J = 14.2, 8.3 Hz, 1H), 7.12–7.00 (m, 2H), 6.92 (d, J =
9.2 Hz, 1H), 5.11–4.95 (m, 1H), 4.00 (dd, J = 14.7, 3.5 Hz, 1H), 3.79
(dd, J = 14.7, 9.4 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.05 (d, J =
579.0 Hz, 1F), 42.31 (d, J = 582.8 Hz, 1F), -111.19 (s, 1F); 13C NMR
(151 MHz, CDCl3) δ 162.71 (d, J = 248.3 Hz), 137.38, 132.70, 130.75
(d, J = 8.3 Hz), 129.70, 129.50, 125.60 (d, J = 2.6 Hz), 117.31, 117.24
22.0 Hz), 72.75, 55.84; IR (KBr, cmꢀ 1):
ν 3104, 2943, 2853, 1606, 1532,
1513, 1404, 1350, 1307, 1234, 1148, 1084; HRMS-EI (m/z) calcd. for
(C14H11N2O4F3S-F2) 322.0424, found 322.0425.
(d, J = 20.9 Hz), 116.71 (d, J = 23.1 Hz), 73.14, 55.52; IR (KBr, cmꢀ 1):
ν
3095, 2994, 2944, 1592, 1493, 1454, 1396, 1333, 1306,1251, 1143,
1089, 1008; HRMS-EI (m/z) calcd. for (C14H11NO2F3SCl-F2) 311.0183,
found 311.0184.
4.3.25. 1-(2-chlorophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3y)
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 7.74 (d, J = 7.3 Hz,
2H), 7.54 (t, J = 7.5 Hz, 1H), 7.40 (t, J = 7.8 Hz, 2H), 7.36 (d, J = 8.1 Hz,
1H), 7.26–7.21 (m, 1H), 7.19 (d, J = 7.1 Hz, 1H), 7.12 (t, J = 7.5 Hz,
1H), 5.69 (tdd, J = 25.7, 9.4, 4.7 Hz, 1H), 4.04 (dd, J = 14.8, 3.4 Hz,
1H), 3.91 (dd, J = 14.8, 9.5 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.86
(d, J = 579.0 Hz, 1F), 41.64 (d, J = 579.0 Hz, 1F); 13C NMR (101 MHz,
CDCl3) δ 138.58, 135.86, 134.19, 131.18, 130.31, 130.26, 129.37,
4.3.20. N,N-difluoro-1-(3-fluorophenyl)-2-((4-nitrophenyl)sulfonyl)
ethan-1-amine (3t)
A yellow solid; m.p.: 69.5–71.0 ◦C; 1H NMR (400 MHz, CDCl3) δ 8.27
(d, J = 8.8 Hz, 2H), 7.90 (d, J = 8.8 Hz, 2H), 7.32 (s, 1H), 7.07 (t, J = 8.3
Hz, 2H), 6.92 (d, J = 9.1 Hz, 1H), 5.08 (tdd, J = 23.9, 9.1, 4.0 Hz, 1H),
4.08 (dd, J = 14.9, 4.0 Hz, 1H), 3.86 (dd, J = 14.9, 9.2 Hz, 1H); 19F NMR
(376 MHz, CDCl3) δ 44.78 (d, J = 582.8 Hz, 1F), 42.41 (d, J = 582.8 Hz,
1F), -110.77 (s, 1F); 13C NMR (151 MHz, CDCl3) δ 162.74 (d, J = 248.8
Hz), 150.98, 144.52, 132.35 (q, J = 5.9 Hz), 130.91 (d, J = 8.1 Hz),
129.58, 125.65 (d, J = 2.7 Hz), 124.48, 117.55 (d, J = 20.9 Hz), 116.74
128.37 (t, J = 5.8 Hz), 127.99, 127.24, 69.55, 54.81; IR (ATR, cmꢀ 1):
ν
3066, 2927, 1479, 1446, 1309, 1149, 1086; HRMS-EI (m/z) calcd. for
(C14H12NO2F2SCl-F2) 293.0277, found 293.0275.
(d, J = 22.4 Hz), 72.97, 55.61; IR (KBr, cmꢀ 1):
ν
3109, 2996, 2941,
4.3.26. 1-(2-chlorophenyl)-N,N-difluoro-2-tosylethan-1-amine (3z)
A yellow solid; m.p.: 53.5–54.7 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.64
(d, J = 8.2 Hz, 2H), 7.38 (d, J = 8.0 Hz, 1H), 7.30–7.25 (m, 1H), 7.21 (d,
J = 7.9 Hz, 3H), 7.19–7.13 (m, 1H), 5.75–5.58 (m, 1H), 4.02 (dd, J =
14.7, 3.3 Hz, 1H), 3.88 (dd, J = 14.7, 9.5 Hz, 1H), 2.38 (s, 3H); 19F NMR
(376 MHz, CDCl3) δ 45.73 (d, J = 579.0 Hz, 1F), 41.62 (d, J = 579.0 Hz,
1F); 13C NMR (151 MHz, CDCl3) δ 145.35, 135.93, 135.61, 130.98,
130.29, 129.99, 129.87, 128.55 (t, J = 5.2 Hz), 128.07, 127.20, 69.50,
1610, 1534, 1490, 1404, 1350, 1309, 1244, 1149, 1085; HRMS-EI (m/z)
calcd. for (C14H11N2O4F3S-F2) 322.0424, found 322.0427.
4.3.21. N,N-difluoro-1-(4-fluorophenyl)-2-(phenylsulfonyl)ethan-1-amine
(3u)
A white solid; m.p.: 80.3–81.4 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.69
(d, J = 7.3 Hz, 2H), 7.59 (t, J = 7.5 Hz, 1H), 7.44 (t, J = 7.8 Hz, 2H), 7.21
(dd, J = 8.6, 5.2 Hz, 2H), 6.96 (t, J = 8.6 Hz, 2H), 5.12–4.95 (m, 1H),
4.01 (dd, J = 14.6, 3.4 Hz, 1H), 3.82 (dd, J = 14.6, 9.6 Hz, 1H); 19F NMR
(376 MHz, CDCl3) δ 44.82 (d, J = 579.0 Hz, 1F), 41.68 (d, J = 575.3 Hz,
1F), -110.54 (s, 1F); 13C NMR (151 MHz, CDCl3) δ 163.63 (d, J = 249.8
54.83, 21.68; IR (ATR, cmꢀ 1):
ν 3068, 2932, 1596, 1478, 1442, 1303,
1142, 1087, 1037; HRMS-EI (m/z) calcd. for (C15H14NO2F2SCl-F2)
307.0434, found 307.0433.
9

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
4.3.27. 1-(2-chlorophenyl)-N,N-difluoro-2-((4-nitrophenyl)sulfonyl)
2.38 (s, 3H); 19F NMR (376 MHz, CDCl3) δ 45.72 (d, J = 582.8 Hz, 1F),
40.79 (d, J = 582.8 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 145.30,
135.51, 133.61, 131.16, 130.37, 129.95, 128.31, 128.05, 127.77,
126.60, 71.85, 54.81, 21.69; HRMS-EI (m/z) calcd. for
(C15H14NO2F2SBr-F2) 350.9929, found 350.9930.
ethan-1-amine (3aa)
1
◦
A white solid; m.p.: 138.1–138.6 C; H NMR (400 MHz, CDCl3) δ
8.23 (d, J = 8.8 Hz, 2H), 7.93 (d, J = 8.8 Hz, 2H), 7.38 (d, J = 8.1 Hz,
1H), 7.30–7.26 (m, 1H), 7.15 (dt, J = 14.9, 6.7 Hz, 2H), 5.80–5.62 (m,
1H), 4.13 (dd, J = 15.0, 3.5 Hz, 1H), 3.97 (dd, J = 15.0, 9.4 Hz, 1H); 19
F
NMR (376 MHz, CDCl3) δ 46.02 (d, J = 582.8 Hz, 1F), 41.96 (d, J =
579.0 Hz, 1F); 13C NMR (151 MHz, CDCl3) δ 150.97, 144.16, 135.97,
131.53, 130.56, 130.31, 129.64, 128.12 (t, J = 5.2 Hz), 127.42, 124.43,
4.3.33. 1-(3-bromophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3ag)
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 7.68 (d, J = 7.4 Hz,
2H), 7.58 (t, J = 7.4 Hz, 1H), 7.43 (t, J = 7.8 Hz, 3H), 7.29 (s, 1H),
7.22–7.13 (m, 2H), 5.00 (tdd, J = 24.6, 9.5, 3.3 Hz, 1H), 4.00 (dd, J =
14.7, 3.4 Hz, 1H), 3.81 (dd, J = 14.7, 9.5 Hz, 1H); 19F NMR (376 MHz,
69.37, 54.99; IR (KBr, cmꢀ 1):
ν 3108, 2931, 1609, 1532, 1476, 1443,
1412, 1350, 1308, 1149, 1086, 1040; HRMS-EI (m/z) calcd. for
(C14H11N2O4F2ClS-F2) 338.0128, found 338.0126.
CDCl3) δ 45.28 (d, J = 579.0 Hz, 1F), 42.63 (d, J = 579.0 Hz, 1F); 13
C
4.3.28. 1-(3-chlorophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3ab)
NMR (101 MHz, CDCl3) δ 138.75, 134.28, 133.17, 132.54, 130.46,
129.52, 129.34, 128.45, 127.90, 122.90, 73.19, 55.22; IR (ATR, cmꢀ 1):
ν
A colorless liquid; 1H NMR (400 MHz, CDCl3) δ 7.68 (d, J = 7.3 Hz,
2H), 7.57 (t, J = 7.5 Hz, 1H), 7.42 (t, J = 7.8 Hz, 2H), 7.29 (d, J = 8.3 Hz,
1H), 7.21 (t, J = 8.1 Hz, 1H), 7.14 (d, J = 6.2 Hz, 2H), 5.01 (tdd, J =
24.6, 9.5, 3.4 Hz, 1H), 4.00 (dd, J = 14.7, 3.4 Hz, 1H), 3.82 (dd, J =
14.7, 9.5 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.23 (d, J = 579.0 Hz,
1F), 42.56 (d, J = 579.0 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 138.74,
134.82, 134.26, 132.30 (t, J = 6.2 Hz), 130.23, 129.69, 129.61, 129.33,
127.90, 127.80, 73.16, 55.13; HRMS-EI (m/z) calcd. for
(C14H12NO2F2ClS-F2) 293.0277, found 293.0267.
3066, 2928, 2850, 1572, 1477, 1448, 1307, 1146, 1085; HRMS-EI (m/z)
calcd. for (C14H12NO2F2SBr-F2) 336.9772, found 336.9768.
4.3.34. 1-(4-bromophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3ah)
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 7.67 (d, J = 7.3 Hz,
2H), 7.62–7.56 (m, 1H), 7.45–7.37 (m, 4H), 7.09 (d, J = 8.4 Hz, 2H),
5.01 (tdd, J = 24.8, 9.6, 3.3 Hz, 1H), 3.99 (dd, J = 14.6, 3.4 Hz, 1H),
3.81 (dd, J = 14.6, 9.6 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ 45.13 (d, J
= 579.0 Hz, 1F), 42.37 (d, J = 579.0 Hz, 1F); 13C NMR (101 MHz, CDCl3)
δ 138.93, 134.09, 132.15, 131.26, 129.46, 129.41, 127.93, 124.53,
73.18, 55.33; HRMS-EI (m/z) calcd. for (C14H12NO2F2SBr-F2) 336.9772,
found 336.9748.
4.3.29. 1-(3-chlorophenyl)-2-((4-chlorophenyl)sulfonyl)-N,N-
difluoroethan-1-amine (3ac)
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 7.59 (d, J = 8.6 Hz,
2H), 7.38 (d, J = 8.6 Hz, 2H), 7.34 (d, J = 8.2 Hz, 1H), 7.26–7.22 (m,
1H), 7.14 (d, J = 8.2 Hz, 2H), 5.00 (tdd, J = 24.2, 9.6, 3.4 Hz, 1H), 4.01
(dd, J = 14.7, 3.5 Hz, 1H), 3.81 (dd, J = 14.7, 9.6 Hz, 1H); 19F NMR (376
MHz, CDCl3) δ 45.05 (d, J = 582.8.0 Hz, 1F), 42.54 (d, J = 579.0 Hz, 1F);
13C NMR (151 MHz, CDCl3) δ 141.20, 137.28, 135.06, 132.13 (t, J = 5.6
Hz), 130.35, 130.33, 129.74, 129.68, 129.43, 128.12, 73.22, 55.36; IR
4.3.35. 1-(3-bromophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3ai)
1
◦
A white solid; m.p.: 102.1–103.3 C; H NMR (400 MHz, CDCl3) δ
7.53 (d, J = 8.3 Hz, 2H), 7.39 (d, J = 8.5 Hz, 2H), 7.21 (d, J = 8.0 Hz,
2H), 7.07 (d, J = 8.4 Hz, 2H), 5.06–4.89 (m, 1H), 3.96 (dd, J = 14.6, 3.3
Hz, 1H), 3.77 (dd, J = 14.5, 9.8 Hz, 1H), 2.42 (s, 3H); 19F NMR (376
MHz, CDCl3) δ 45.01 (d, J = 579.0 Hz, 1F), 42.32 (d, J = 579.0 Hz, 1F);
13C NMR (151 MHz, CDCl3) δ 145.51, 135.97, 132.14, 131.33, 130.03,
129.56 (t, J = 5.3 Hz), 128.03, 124.52, 73.31, 55.39, 21.78; IR (KBr,
(ATR, cmꢀ 1):
ν 3093, 2926, 1580, 1476, 1332, 1147, 1089; HRMS-EI
(m/z) calcd. for (C14H11NO2F2SCl2-F2) 326.9888, found 326.9891.
4.3.30. 1-(4-chlorophenyl)-N,N-difluoro-2-tosylethan-1-amine (3ad)
A white solid; m.p.: 94.1–97.2 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.54
(d, J = 8.3 Hz, 2H), 7.26–7.20 (m, 4H), 7.15 (d, J = 8.5 Hz, 2H), 4.99
(tdd, J = 24.7, 9.7, 3.2 Hz, 1H), 3.97 (dd, J = 14.6, 3.4 Hz, 1H), 3.78 (dd,
J = 14.5, 9.7 Hz, 1H), 2.42 (s, 3H); 19F NMR (376 MHz, CDCl3) δ 44.96
(d, J = 575.3 Hz, 1F), 42.22 (d, J = 579.0 Hz, 1F); 13C NMR (151 MHz,
CDCl3) δ 145.48, 136.27, 135.99, 131.07, 130.01, 129.17, 129.08 (t, J
cmꢀ 1):
ν 3097, 3056, 2926, 1639, 1594, 1491, 1415, 1327, 1301, 1146,
1082, 1009; HRMS-EI (m/z) calcd. for (C15H14NO2F2SBr-F2) 352.9912,
found 352.9908.
4.3.36. 1-(4-(tert-butyl)phenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-
amine (3aj)
= 5.8 Hz), 128.04, 73.21, 55.45, 21.74; IR (KBr, cmꢀ 1):
ν
3058, 2927,
A yellow solid; m.p.: 97.3–98.6 ◦C; 1H NMR (400 MHz, CDCl3) δ 7.53
(d, J = 7.5 Hz, 2H), 7.38 (t, J = 7.5 Hz, 1H), 7.23 (t, J = 7.8 Hz, 2H), 7.13
(d, J = 8.3 Hz, 2H), 7.00 (d, J = 8.3 Hz, 2H), 4.93 (tdd, J = 26.1, 9.3, 3.2
Hz, 1H), 3.95 (dd, J = 14.7, 3.4 Hz, 1H), 3.80 (dd, J = 14.7, 9.5 Hz, 1H),
1.17 (s, 9H); 19F NMR (376 MHz, CDCl3) δ 45.58 (d, J = 575.3 Hz, 1F),
41.52 (d, J = 575.3 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 152.97,
138.93, 133.75, 129.32, 129.09, 127.90, 127.19–126.95 (m), 125.79,
73.61, 55.15, 34.65, 31.16; HRMS-EI (m/z) calcd. for (C18H21NO2F2S-
F2) 315.1293, found 315.1286.
1639, 1596, 1493, 1416, 1326, 1303, 1146, 1088; HRMS-EI (m/z) calcd.
for (C15H14NO2F2SCl-F2) 307.0434, found 307.0433.
4.3.31. 1-(4-chlorophenyl)-2-((4-chlorophenyl)sulfonyl)-N,N-
difluoroethan-1-amine (3ae)
1
◦
A white solid; m.p.: 102.4–103.6 C; H NMR (400 MHz, CDCl3) δ
7.60 (d, J = 8.6 Hz, 2H), 7.41 (d, J = 8.7 Hz, 2H), 7.28 (d, J = 8.5 Hz,
2H), 7.16 (d, J = 8.5 Hz, 2H), 5.01 (tdd, J = 24.4, 9.5, 3.6 Hz, 1H), 4.00
(dd, J = 14.7, 3.6 Hz, 1H), 3.79 (dd, J = 14.6, 9.5 Hz, 1H); 19F NMR (376
MHz, CDCl3) δ 44.79 (d, J = 579.0 Hz, 1F), 42.25 (d, J = 582.8 Hz, 1F);
13C NMR (151 MHz, CDCl3) δ 141.20, 137.44, 136.59, 131.05, 129.74,
4.3.37. N,N-difluoro-1-(naphthalen-2-yl)-2-(phenylsulfonyl)ethan-1-
amine (3ak)
129.48, 129.33, 128.84 (t, J = 5.8 Hz), 73.03, 55.57; IR (KBr, cmꢀ 1):
ν
A reddish brown solid; m.p.: 96.7–97.4 ◦C; 1H NMR (400 MHz,
CDCl3) δ 7.70 (d, J = 7.5 Hz, 1H), 7.68–7.60 (m, 3H), 7.53 (d, J = 7.7 Hz,
2H), 7.47–7.39 (m, 2H), 7.26 (t, J = 7.7 Hz, 1H), 7.18 (d, J = 8.6 Hz,
1H), 7.16–7.08 (m, 2H), 5.12 (td, J = 24.7, 8.9 Hz, 1H), 4.02 (d, J = 14.6
Hz, 1H), 3.95–3.84 (m, 1H); 19F NMR (376 MHz, CDCl3) δ 46.07 (d, J =
575.3 Hz, 1F), 42.33 (d, J = 579.0 Hz, 1F); 13C NMR (151 MHz, CDCl3) δ
139.02, 133.83, 133.80, 132.92, 130.28, 129.11, 128.98, 128.32,
3092, 3002, 2939, 1582, 1494, 1476, 1415, 1329, 1307, 1146, 1089;
HRMS-EI (m/z) calcd. for (C14H11NO2F2SCl2-F2) 326.9888, found
326.9883.
4.3.32. 1-(2-bromophenyl)-N,N-difluoro-2-(phenylsulfonyl)ethan-1-amine
(3af)
A yellow liquid; 1H NMR (400 MHz, CDCl3) δ 7.65 (d, J = 8.2 Hz,
2H), 7.60–7.55 (m, 1H), 7.22 (s, 1H), 7.21–7.17 (m, 4H), 5.78–5.61 (m,
1H), 4.03 (dd, J = 14.8, 3.3 Hz, 1H), 3.88 (dd, J = 14.7, 9.4 Hz, 1H),
127.96, 127.76, 127.43, 126.87, 125.69, 74.09, 55.64; IR (KBr, cmꢀ 1):
ν
3064, 2932, 1601, 1580, 1508, 1474, 1446, 1412, 1302, 1236, 1146,
1084; HRMS-EI (m/z) calcd. for (C18H15NO2F2S-F2) 309.0824, found
10

W. Zhang and X. Yang
Journal of Fluorine Chemistry 248 (2021) 109823
309.0830.
257.0511, found 257.0517.
4.3.45. 1-phenyl-2-(phenylsulfonyl)ethan-1-one oxime (9)
4.3.38. N,N-difluoro-1-(4-methoxyphenyl)-2-(phenylsulfonyl)ethan-1-
amine (3al)
1
◦
A white solid; m.p.: 126.1–127.9 C; H NMR (400 MHz, CDCl3) δ
8.58 (s, 1H), 7.93 (d, J = 7.7 Hz, 2H), 7.69 (t, J = 7.4 Hz, 1H), 7.57 (t, J
= 7.7 Hz, 2H), 7.49 (d, J = 7.9 Hz, 2H), 7.33 (t, J = 7.8 Hz, 2H), 7.16 (t,
J = 7.4 Hz, 1H), 4.20 (s, 2H); 13C NMR (101 MHz, CDCl3) δ 158.64,
134.80, 129.72, 129.24, 128.29, 125.35, 120.35, 63.10; HRMS-EI (m/z)
calcd. for (C14H15NO3S) 275.0616, found 275.0613.
Brown liquid; 1H NMR (400 MHz, CDCl3) δ 7.67 (d, J = 7.3 Hz, 2H),
7.55 (t, J = 7.0 Hz, 1H), 7.41 (t, J = 7.8 Hz, 2H), 7.12 (d, J = 8.7 Hz, 2H),
6.76 (d, J = 8.8 Hz, 2H), 4.98 (tdd, J = 26.0, 9.5, 3.5 Hz, 1H), 4.01 (dd, J
= 14.6, 3.5 Hz, 1H), 3.87–3.80 (m, 1H), 3.77 (s, 3H); 19F NMR (376
MHz, CDCl3) δ 44.99 (d, J = 575.3 Hz, 1F), 41.13 (d, J = 571.5 Hz, 1F);
13C NMR (101 MHz, CDCl3) δ 160.80, 139.18, 133.93, 131.03 (d, J = 7.0
Hz), 129.28, 128.02, 122.30 (t, J = 6.1 Hz), 114.36 (d, J = 8.5 Hz),
73.27, 55.51, 55.37; HRMS-EI (m/z) calcd. for (C15H15NO3F2S-F2)
289.0773, found 289.0776.
Declaration of Competing Interest
We declare that we have no financial and personal relationships with
other people or organizations that can inappropriately influence our
work, there is no professional or other personal interest of any nature or
kind in any product, service and/or company that could be construed as
influencing the position presented in, or the review of, the manuscript
entitled “Difluoroaminosulfonylation of Styrenes with N,N-
Difluorobenzenesulfonamide”.
4.3.39. methyl 4-(1-(difluoroamino)-2-(phenylsulfonyl)ethyl)benzoate
(3am)
Colorless liquid; 1H NMR (400 MHz, CDCl3) δ 7.86 (d, J = 8.4 Hz,
2H), 7.62 (d, J = 7.3 Hz, 2H), 7.48 (t, J = 7.5 Hz, 1H), 7.33 (t, J = 7.8 Hz,
2H), 7.25 (d, J = 8.3 Hz, 2H), 5.03 (tdd, J = 24.7, 9.3, 3.3 Hz, 1H), 3.95
(dd, J = 14.6, 3.5 Hz, 1H), 3.83 (s, 3H), 3.78 (dd, J = 14.6, 9.3 Hz, 1H);
19F NMR (376 MHz, CDCl3) δ 45.46 (d, J = 582.8 Hz, 1F), 42.82 (d, J =
579.0 Hz, 1F); 13C NMR (101 MHz, CDCl3) δ 166.14, 138.76, 135.21 (t,
J = 5.9 Hz), 134.15, 131.53, 129.96, 129.67, 129.33, 127.88, 73.22,
55.26, 52.47; HRMS-EI (m/z) calcd. for (C16H15NO4F2S-F2) 317.0722,
found 317.0732.
Acknowledgments
This study was financially supported by the National Natural Science
Foundation of China (21372077) and by State Key Laboratory of Effi-
cient Utilization for Low Grade Phosphate Rock and Its Associated Re-
sources (WFKF2017-04).
4.3.40. N-fluoro-2-(phenylsulfonyl)-1-(pyridin-2-yl)ethan-1-imine (4)
A brown solid; m.p.: 100.6–101.4 ◦C; 1H NMR (400 MHz, CDCl3) δ
8.53–8.47 (m, 1H), 7.88 (d, J = 7.9 Hz, 1H), 7.83 (d, J = 7.6 Hz, 2H),
7.75 (t, J = 7.8 Hz, 1H), 7.59 (t, J = 7.2 Hz, 1H), 7.46 (t, J = 7.4 Hz, 2H),
Supplementary materials
Supplementary material associated with this article can be found, in
the online version, at doi:10.1016/j.jfluchem.2021.109823.
7.35 (s, 1H), 5.11 (s, 2H); 19F NMR (376 MHz, CDCl3) δ 37.50 (s, 1F); 13
C
NMR (151 MHz, CDCl3) δ 159.90 (d, J = 17.6 Hz), 149.53, 147.82 (d, J
= 20.7 Hz), 139.42, 137.17, 134.21, 129.19, 128.47, 125.97, 122.60,
Reference
52.16 (d, J = 22.3 Hz); IR (KBr, cmꢀ 1):
ν 3072, 3003, 2929, 1573, 1472,
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