Efficient copper-induced coupling between NH-fluoroalkylated sulfoximines and aryl iodides or bromides

Article abstract of DOI:10.1016/j.tet.2011.07.060

A high yielding, simple, and flexible copper-based system for N-arylation of fluorinated sulfoximines is reported. Best results were achieved using copper iodide in combination with DMEDA and Cs₂CO₃ to provide a wide range of N-aryla

Full text of DOI:10.1016/j.tet.2011.07.060

Tetrahedron 67 (2011) 7575e7580
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Efficient copper-induced coupling between NH-fluoroalkylated sulfoximines
and aryl iodides or bromides
,
b
a
b
b
b
ꢀ a
ꢀ
ꢀ
ꢀ
Yohan Mace , Bruce Pegot , Regis Guillot , Chloee Bournaud , Martial Toffano ,
Giang Vo-Thanh b , Emmanuel Magnier
Institut Lavoisier de Versailles, UMR CNRS 8180, Universite de Versailles St-Quentin-Yvelines, 45 avenue des Etats-Unis, 78035 Versailles Cedex, France
,
a,
*
*
a
ꢀ
b
ꢀ
ꢀ
ꢀ
ꢀ
Laboratoire de Catalyse Moleculaire, Institut de Chimie Moleculaire et des Materiaux d’Orsay, UMR 8182, Universite Paris-Sud 11, 91405 Orsay Cedex, France
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 25 May 2011
Received in revised form 16 July 2011
Accepted 21 July 2011
Available online 26 July 2011
A high yielding, simple, and flexible copper-based system for N-arylation of fluorinated sulfoximines is
reported. Best results were achieved using copper iodide in combination with DMEDA and Cs2CO3 to
provide a wide range of N-arylated perfluoroalkylated sulfoximines. These conditions tolerate a great
number of substituents on either aromatic cycle, including heteroaromatic rings, for the N-
functionalization.
Ó 2011 Elsevier Ltd. All rights reserved.
Keywords:
Copper
Fluorinated ligands
Nitrogen
Sulfoximines
Sulfur
1. Introduction
In connection with studies devoted to the preparation of fluo-
rinated sulfilimines, we recently unlocked the access to fluo-
Sulfoximines bear uncommon and intriguing sulfur (VI) func-
tionality. The extensive variety of existing synthetic methods offers
an easy access to these molecules, including their preparation in
pure enantiomeric form.1 These broad synthetic opportunities have
stimulated widespread applications for sulfoximines as chiral
auxiliary,2 ligand in asymmetric catalysis,3 and biologically active
group in life sciences.4 Surprisingly, the field of application is more
restricted for S-perfluoroalkyl sulfoximines presumably because of
their so far cumbersome synthesis. Nevertheless, some recent ap-
plications made them very attractive tools. They have been indeed
described as very powerful electron withdrawing groups,5
employed for material science purposes6 and above all, in-
troduced as very efficient electrophilic fluoroalkylating reagents as
recently demonstrated by Shibata for trifluoro- and mono-
fluoromethylation,7 Hu for difluoromethylation,8 and us for bro-
modifluoro- and dichloromethylation.9
roalkylated aryl sulfoximines by the discovery of a safe method,
avoiding the use of solvent and toxic reagents.10
Our versatile approach allowed the variation of the aromatic
substituent, the nature of the fluorinated chain (from tri-
fluoromethyl to perfluoroalkyl) and moreover, the scalable iso-
lation of free NH-sulfoximines, enabling thus further post-
functionalization. In this article, we disclose our results concern-
ing the copper promoted N-arylation11 of fluorinated sulfoximines,
as a part of our studies devoted to a better understanding of the
peculiar reactivity of this nitrogen atom.
2. Results and discussion
The optimization of reaction conditions was first carried out
with trifluoromethyl phenyl sulfoximine 1a and phenyl iodide 2a.
The influence of reaction parameters was evaluated and is sum-
marized in Table 1.
Preliminary blank experiments revealed the importance of the
metal as well as the ligand for the success of the coupling (entries 1
and 6). A set of copper salts, introduced in stoichiometric amount,
was then investigated (entries 2e5). Good yields of functionalized
sulfoximine 3a were obtained whatever the nature of the salt. As
copper iodide showed the best performance (entry 5), this reagent
was chosen as our standard for the next studies. The use of
These former challenging discoveries nicely illustrate the need
and the importance to develop new, pathway for the synthesis of
various S-perfluoroalkylated sulfoximines.
* Corresponding authors. Tel.: þ33 1 39 25 44 66; fax: þ33 1 39 25 44 52 (E.M.);
tel.: þ33 1 69 15 78 91; fax: þ33 1 69 15 46 80 (G.V.-T.); e-mail addresses:
giang.vo-thanh@u-psud.fr (G. Vo-Thanh), magnier@chimie.uvsq.fr (E. Magnier).
0040-4020/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2011.07.060

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Y. Mace et al. / Tetrahedron 67 (2011) 7575e7580
Table 1
Table 2
Evaluation of the reaction conditions for the coupling of sulfoximine 1a with phenyl
iodide 2a
Copper-catalyzed N-arylation of trifluoromethyl phenylsulfoximine 1a with aryl
halides 2aeoa
NH
O
N
O
CuX, ligand
S
+
CF3
S
CF
3
base,solvent
reflux, 20 h
I
1a
2a
3a
Entry Copper Equiv Ligand
salta
Base
Solvent Yieldb
%
1
2
3
4
5
6
7
8
d
d
1
1
1
1
1
1
1
1
1
1
1
0.5
DMEDA
DMEDA
DMEDA
DMEDA
DMEDA
d
Cs2CO3 Toluene 0c
Cs2CO3 Toluene 81
Cs2CO3 Toluene 80
Cs2CO3 Toluene 86
Cs2CO3 Toluene 96
Cs2CO3 Toluene 0c
Cs2CO3 Toluene 70
Entry
Aryl halide
X
R
Product
Yieldb
%
CuSO4
CuCl
CuBr
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
1
2
3
4
5
6
7
8
2a
2b
2c
2d
2e
2f
2g
2h
2i
2j
2k
2l
2m
2n
2o
I
I
I
I
I
I
I
I
H
3a
3b
3c
3d
3e
3f
3g
3h
3i
97
98
99
99
97
>99
>99
98
99
98
2-Me
3-Me
4-Me
3,5-Me
4-NO2
4-CO2Et
2-OMe
3-OMe
4-OMe
H
TMEDA
N,N-Dimethylethylenediamine Cs2CO3 Toluene 76
Proline
cis 1,2-Diaminocyclohexane
DMEDA
DMEDA
DMEDA
9
Cs2CO3 Toluene 82
Cs2CO3 Toluene 96
Na2CO3 Toluene 90
K2CO3 Toluene 90
Cs2CO3 Toluene 94
Cs2CO3 Toluene 3c
10
11
12
13
14
15
16
17
18
19
9
I
I
10
11
12
13
14
15
3j
Br
Br
Br
Br
Cl
3a
3h
3i
3j
3a
92
99
99
2-OMe
3-OMe
4-OMe
H
0.25 DMEDA
0.1
0.1
0.5
0.5
0.5
DMEDA
DMEDAd
DMEDA
DMEDA
DMEDA
Cs2CO3 Toluene Tracesc
Cs2CO3 Toluene 52
Cs2CO3 DMSO 20
Cs2CO3 Dioxane 91
98
Tracesc
a
Reaction conditions: sulfoximine 1a (1.0 equiv), aryl halide (2.0 equiv), CuI
Cs2CO3 THF
92
(50 mol %), DMEDA (1.0 equiv), Cs2CO3 (2.5 equiv) in toluene (1 M) at 110 ꢀC.
b
a
Isolated yield.
Starting material 1a was degraded.
Reaction conditions otherwise stated: sulfoximine 1a (1.0 equiv), phenyl iodide
2a (2.0 equiv), base (2.5 equiv), copper salt, ligand (twice the quantity of copper
salt), solvent (1 M).
c
b
Isolated yield.
Starting material 1a was degraded.
1.0 equiv related to 1a.
c
of compound 2e (entry 5). The presence of electron withdrawing
substituents, such as nitro or ester (entries 6 and 7) are not dele-
terious to the yield. Moreover, a direct comparison between aryl
iodides 2a, 2hej and aryl bromides 2ken for this coupling reaction
showed that both aryl halides reacted equally well and gave
quantitative yields (entries 1, 8e10 vs 11e14). Unsurprisingly, no
reaction occurred with chlorobenzene2o (entry 15).18
The reactivity of variously substituted perfluoroalkyl aryl sul-
foximines has been also evaluated during the cross coupling pro-
cess. The results are reported in Table 3.
d
TMEDA,12N,N-dimethylethylenediamine,13 and proline14 (entries
7e9) proved efficient. However, 1,2-diaminocyclohexane and
DMEDA15 (entries 5 and 10) gave the best results and the latter was
chosen for practical convenience. Concerning the influence of the
base cation, cesium proved to be slightly more efficient than so-
dium or potassium (entry 5 vs entries 11 and 12). Another crucial
point that we evaluated was the charge of copper salt. The amount
of copper iodide could be reduced to 50 mol % without real impact
on yield (entry 13), whereas poor yields were obtained below this
amount (entry 14e15). It should be noticed that the quantities
needed are greater than those used for the arylation of non fluo-
rinated sulfoximines.16
Table 3
Copper-catalyzed N-arylation of substituted fluoroalkyl sulfoximine 1beg with
phenyl iodide 2aa
We presume that this effect results from the particular structure
of fluorinated substrate 1a acting as competitive ligand for cop-
per.17To test this hypothesis, we performed an experiment with
a tenfold excess of ligand relative to the copper salt (entry 16).
Under those catalytic conditions, an acceptable yield (52%) was
retrieved but not as high as with a sub-stoichiometric amount of
copper able to achieve a practically quantitative yield for this
transformation. The solvent, toluene gave the best yield (entry 13),
closely followed by dioxane and THF (entries 18 and 19), which
could be used as well, while DMSO gave the poorest yield (entry
17). Finally, experiments described in Table 1, were all conducted
using 20 h reflux for consistency, but the reaction time could be
reduced to 3 h (vide infra) without impact on the yield.
These conditions have been retained for the substrate scope
investigation using various aryl halides. The results are summa-
rized in Table 2.
A wide variety of N-arylated fluoroalkylated aryl sulfoximines
was synthesized in excellent yield from corresponding aryl iodides
(up to 99%, entries 1e10). Two trends are emerging from these
results. The substitution of the aryl iodide has no influence on the
yield as demonstrated by the variation of the position of a methyl
(entries 2e4) or a methoxy group (entries 8e10) as well as the use
Entry
Aryl halide
R
RF
Product
Yieldb (%)
1
2
3
4
5
6
1b
1c
1d
1e
1f
o-Cl
m-Cl
p-Cl
o-Me
p-Me
H
CF3
CF3
CF3
CF3
CF3
C4F9
3k
3l
3m
3n
3o
3p
0c
68
99
99
99
98
1g
a
Reaction conditions: sulfoximine (1.0 equiv), phenyl iodide 2a (2.0 equiv), CuI
(50 mol %), DMEDA (1.0 equiv), Cs2CO3 (2.5 equiv) in toluene (1 M) at 110 ꢀC for 3 h.
b
Isolated yield.
Starting material 1b was degraded.
c
Whereas the methyl group had no influence and allowed
a quantitative transformation (entries 4 and 5), the presence of
a chlorine atom resulted in more contrasted results (entries 1e3).
Its presence was not detrimental to the yield in para position and to
a lesser degree in meta position. However, the reaction was totally
inhibited when this halogen was linked ortho to the sulfoximine
functionality. In this particular case, starting material 1b was fully

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Y. Mace et al. / Tetrahedron 67 (2011) 7575e7580
7577
degraded. We presume that in this case, a new species is formed by
copper insertion into the arylechlorine bond of 1b induced by the
strong stabilizing ortho effect of the sulfoximine.19 The complex
formed may then evolved through decomposition species. Finally
the length of the perfluorinated chain can be increased without loss
of efficiency (entry 6).
Our methodology was further extended to the synthesis of more
elaborated N-aryl sulfoximines in order to demonstrate the func-
tional tolerance of this process (Scheme 1).
excellent yield. This innovative process allows a new and low cost
access to a large panel of N-arylated fluoroalkylated sulfoximines.
Some examples bearing additional functionalities would enable
further transformations.
4. Experimental section
4.1. General
Each reaction was carried out under an argon atmosphere in
a freshly distilled solvent, unless otherwise noted. All chemicals
were purchased from commercial sources (SigmaeAldrich, ABCR or
Alfa Aesar) and were used without further purification. Organic
solvents were purchased from Merck and Carlo Erba. Reactions
were monitored by thin-layer chromatography on silica gel 60 F254
,
or by 19F NMR spectroscopy. Unless otherwise noted, yields refer to
materials purified by column chromatography. NMR spectra were
recorded on a Bruker AC-200 spectrometer. Reported coupling
constants and chemicals shifts were based on a first order analysis.
Internal reference was the residual peak of CHCl3 (7.27 ppm) for 1H
(200 MHz), central peak of CDCl3 (77 ppm) for 13C (50 MHz) spec-
tra, and internal CFCl3 (0 ppm) for 19F (282 MHz) NMR spectra.
High-resolution electrospray mass spectra in the positive ion mode
were obtained on a Xevo Q-Tof WATERS. Melting points were de-
€
termined on a Buchi melting point apparatus. X-ray diffraction data
were collected by using a Kappa X8 APPEX II Bruker diffractometer.
4.2. General procedure for preparation of sulfoximines as
exemplified by the preparation of S-(phenyl)-S-
(trifluoromethyl)-sulfoximine (1a)
Scheme 1. Copper-catalyzed coupling with functionalized aryl iodides. Reaction con-
ditions: sulfoximine 1a (1.0 equiv), aryl halide (2.0 equiv, 1.1 equiv for 2s and 2t), CuI
(50 mol %), DMEDA (1.0 equiv), Cs2CO3 (2.5 equiv) in toluene (1 M) at 110 ꢀC.
Trifluoromethanesulfonate anhydride (6.5 mL, 38.7 mmol,
1.5 equiv) was added under argon to a precooled (ꢁ15 ꢀC) mixture of
phenyl trifluoromethyl sulfoxide (5 g, 25.8 mmol, 1 equiv) and ace-
tonitrile(2 mL, 38.7 mmol,1.5 equiv). Thereactionmixturewasstirred
for 12 h at ꢁ15 ꢀC, and then carefully hydrolyzed with water (5 mL),
sodium hydroxide (2 g, 51.5 mmol, 2 equiv) and potassium perman-
ganate (4 g, 25.8 mmol, 1 equiv) were added, the reaction was heated
at 110 ꢀC for 4 h. The mixture was cooled, cleared with Na2S2O4, then
diluted with water (15 mL), and extracted with CH2Cl2 (3ꢂ20 mL). The
organic layers were dried over MgSO4, and concentrated under re-
duced pressure. The residue was purified by flash chromatography
(SiO2, ether/pentane3/7)togive4.37 g(81%)of1a asawhitesolid. Mp:
We were very pleased to isolate in quantitative yield the sul-
foximines 3q and 3r obtained from the coupling reaction with,
respectively, 2-bromopyridine 2q and 2-iodothiophene 2r. The
presence of a heteroatom in this second aromatic ring is of im-
portance for future developments of fluorinated sulfoximines. In
the same context, with the judicious choice of conditions (1.1 equiv
of aryl halide for 1 equiv of sulfoximine), both bis-iodobenzene 2s
and dibromonaphthalene 2t reacted equally well, to give around
70% yield of halogenated product 3s and 3t. The structure of mol-
ecule 3s has been secured by X-ray analysis (Fig. 1).
89.9ꢃ0.2 ꢀC;19F NMR (188 MHz, CDCl3) (ppm)
d
ꢁ79.3 (3F, s); 1H NMR
(300 MHz, CDCl3) (ppm)
d
8.16 (2H, d, J¼7.3 Hz), 7.83e7.75 (1H, m),
7.69e7.61 (2H, m), 3.62 (1H, br s for NH); 13C NMR (75 MHz, CDCl3)
(ppm)
d
: 35.5, 131.6, 130.6, 129.5, 120.9 (q, J¼332 Hz, CF3); MS (pos.
ESI): m/z¼210 (MHþ), 232 (MNaþ), 441 (2MNaþ).
4.2.1. S-((o-Chloro)phenyl)-S-(trifluoromethyl)-sulfoximine
(1b). Pale yellow oil, yield 49%; 19F NMR (188 MHz, CDCl3) (ppm)
d
ꢁ76.9 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.34 (1H, dd,
J¼8.1, 1.5 Hz), 7.69e7.58 (2H, m), 7.55e7.48 (1H, m), 3.89 (1H, br s
for NH); 13C NMR (75 MHz, CDCl3) (ppm)
d 136.2, 135.1, 134.4, 133.0,
130.3, 127.6, 120.8 (q, J¼333 Hz, CF3); MS (pos. ESI, for 35Cl):
m/z¼173 ([MHꢁCF3]þ), 244 (MHþ); HRMS: calculated for
C7H365ClF3NOS 243.9805 found 243.9810 (
d¼ꢁ2.1 ppm).
4.2.2. S-((m-Chloro)phenyl)-S-(trifluoromethyl)-sulfoximine
(1c). White powder, mp: 37e39 ꢀC, yield 73%; 19F NMR (188 MHz,
Fig. 1. ORTEP drawing of compound 3s with the atom labeling scheme. Ellipsoids are
drawn at the 30% probability level.
CDCl3) (ppm)
d
ꢁ78.9 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
3. Conclusion
d
8.14e8.09 (1H, m), 8.01 (1H, d, J¼8.1 Hz) 7.74e7.67 (1H, m), 7.55
(1H, t, J¼8.1 Hz), 3.94 (1H, br s for NH); 13C NMR (75 MHz, CDCl3)
In summary, we have developed a simple and versatile copper-
catalyzed system for the N-arylation of fluorinated sulfoximines in
(ppm)
d
135.7, 135.5, 133.3, 130.6, 130.3, 128.6, 120.6 (q, J¼332 Hz,
CF3); MS (pos. ESI, for 35Cl): m/z¼173 ([MHꢁCF3]þ), 244 (MHþ);

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Y. Mace et al. / Tetrahedron 67 (2011) 7575e7580
7578
HRMS: calculated for C7H635ClF3NOS 243.9805 found 243.9806
¼ꢁ0.2 ppm).
d 139.8,135.3,132.6,132.2,130.6,130.4,129.5,126.5,123.8,123.1,121.5
(d
(q, J¼339 Hz, CF3), 18.5; MS (pos. ESI): m/z¼322 (MNaþ); HRMS: cal-
culated for C14H12F3NNaOS 322.0489 found 322.0481 (
d¼2.5 ppm).
4.2.3. S-((p-Chloro)phenyl)-S-(trifluoromethyl)-sulfoximine
(1d). Pale yellow powder, mp: 58e60 ꢀC, yield 78%; 19F NMR
4.3.2. N-((m-Methyl)phenyl) phenyl trifluoromethyl sulfoximine
(3c). Yellow oil, yield 99%; 19F NMR (188 MHz, CDCl3) (ppm)
(188 MHz, CDCl3) (ppm)
(ppm)
d
ꢁ79.1 (3F, s); 1H NMR (300 MHz, CDCl3)
d
8.07 (2H, d, J¼8.7 Hz), 7.60 (2H, d, J¼8.9 Hz), 3.80 (1H, br s
d
ꢁ72.5 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.25 (2H, d,
for NH); 13C NMR (75 MHz, CDCl3) (ppm)
d
142.6, 131.9, 130.0, 129.8,
J¼7.5 Hz), 7.83e7.75 (1H, m), 7.71e7.63 (2H, m), 7.21 (1H, t,
120.7 (q, J¼332 Hz, CF3); MS (pos. ESI, for 35Cl): m/z¼173
J¼7.9 Hz), 7.15e7.08 (2H, m), 6.95 (1H, d, J¼7.5 Hz), 2.36 (3H,s); 13C
([MHꢁCF3]þ), 244 (MHþ); HRMS: calculated for C7H635ClF3NOS
NMR (75 MHz, CDCl3) (ppm) d 141.0,139.0, 135.3,131.8, 129.5, 128.9,
243.9805 found 243.9803 (
d
¼1.0 ppm).
124.7, 124.6, 121.4 (q, J¼339 Hz, CF3), 120.9, 21.3; MS (pos. ESI): m/
z¼322 (MNaþ); HRMS: calculated for C14H12F3NNaOS 322.0489
4.2.4. S-((o-Methyl)phenyl)-S-(trifluoromethyl)-sulfoximine
(1e). Pale yellow oil, yield 69%; 19F NMR (188 MHz, CDCl3) (ppm)
found 322.0478 (d¼3.4 ppm).
d
ꢁ78.9 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d
8.22 (1H, d,
4.3.3. N-((p-Methyl)phenyl) phenyl trifluoromethyl sulfoximine
(3d). Brown powder, mp: 59e61 ꢀC, yield 99%; 19F NMR (188 MHz,
J¼8.1 Hz), 7.63e7.53 (1H, m), 7.45e7.33 (2H, m), 3.70 (1H, br s for
NH), 2.78 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
d
141.7, 135.2,
CDCl3) (ppm)
d
ꢁ72.4 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
133.5, 132.9, 129.7, 126.8, 121.2 (q, J¼333 Hz, CF3), 21.1; MS (pos.
d
8.25 (2H, d, J¼7.9 Hz), 7.83e7.75 (1H, m), 7.70e7.62 (2H, m), 7.20
ESI): m/z¼224 (MHþ); HRMS: calculated for C8H9F3NOS 224.0357
(2H, d, J¼8.3 Hz), 7.13 (2H, d, J¼8.1 Hz), 2.34 (3H,s); 13C NMR
found 224.0355 (
d¼1.1 ppm).
(75 MHz, CDCl3) (ppm) d 138.4, 135.3, 133.3, 131.8, 130.5, 129.8,
129.5, 123.7, 121.4 (q, J¼340 Hz, CF3), 20.8; MS (pos. ESI): m/z¼253
4.2.5. S-((p-Methyl)phenyl)-S-(trifluoromethyl)-sulfoximine
(1f). White powder, mp: 69.3ꢃ0.2 ꢀC, yield 72%; 19F NMR
([MNaꢁCF3]þ), 322 (MNaþ); HRMS: calculated for C14H12F3NNaOS
322.0484 found 322.0481 (
d
¼0.8 ppm).
(188 MHz, CDCl3) (ppm)
(ppm)
d
ꢁ79.5 (3F, s); 1H NMR (300 MHz, CDCl3)
d
8.03 (2H, d, J¼8.3 Hz), 7.43 (2H, d, J¼8.1 Hz), 3.47 (1H, br s
4.3.4. N-((3,5-Dimethyl)phenyl) phenyl trifluoromethyl sulfoximine
(3e). Brown oil, yield 97%; 19F NMR (188 MHz, CDCl3) (ppm)
for NH), 2.50 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
d 146.9, 130.6,
130.2, 128.6, 121.0 (q, J¼332 Hz, CF3), 21.7; MS (pos. ESI): m/z¼224
d
ꢁ72.5 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.25 (2H, d,
(MHþ), 246 (MNaþ); HRMS: calculated for C8H9F3NOS 224.0351
J¼7.3 Hz), 7.83e7.75 (1H, m), 7.70e7.62 (2H, m), 6.95 (2H, s), 6.78
found 224.0361 (
d¼ꢁ4.2 ppm).
(1H, s) 2.33 (6H, s); 13C NMR (75 MHz, CDCl3) (ppm)
d 140.8, 138.7,
135.2, 131.9, 130.5, 129.4, 125.7, 121.6, 121.4 (q, J¼339 Hz, CF3), 21.2;
4.2.6. S-(Phenyl)-S-(nonafluorobutyl)-sulfoximine
(1g). Colorless
ꢁ81.3 (3F, m),
MS (pos. ESI): m/z¼267 ([MNaꢁCF3]þ), 336 (MNaþ); HRMS: cal-
oil, yield 75%; 19F NMR (188 MHz, CDCl3) (ppm)
d
culated for C15H14F3NNaOS 336.0640 found 336.0634 (
d
¼1.9 ppm).
ꢁ111.6 (2F, m), ꢁ121.0 (2F, m), ꢁ126.5 (2F, m); 1H NMR (300 MHz,
CDCl3) (ppm)
d
8.14 (2H, d, J¼7.9 Hz), 7.77e7.70 (1H, m), 7.64e7.55
4.3.5. N-((p-Nitro)phenyl) phenyl trifluoromethyl sulfoximine
(3f). Yellow powder, mp: 62e64 ꢀC, yield 100%; 19F NMR (188 MHz,
(2H, m), 4.03 (1H, br s for NH); 13C NMR (75 MHz, CDCl3) (ppm)
d
135.4, 132.3, 130.8, 129.2; MS (pos. ESI): m/z¼360 (MHþ); HRMS:
CDCl3) (ppm)
d
ꢁ73.2 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
calculated for C10H7F9NOS 360.0099 found 360.0100 (
d¼ꢁ0.1 ppm).
d
8.20 (2H, d, J¼7.5 Hz), 8.15 (2H, d, J¼9.3 Hz), 7.95e7.80 (1H, m),
7.74e7.65 (2H, m), 7.34 (2H, d, J¼9.2 Hz); 13C NMR (75 MHz, CDCl3)
4.3. General procedure for N-arylations of sulfoximines as
exemplified by the preparation of N-(phenyl) phenyl
trifluoromethyl sulfoximine (3a)
(ppm) d 148.4, 143.6, 138.6, 136.1, 130.4, 129.8, 125.0, 124.7, 123.9,
121.1 (q, J¼337 Hz, CF3); MS (pos. ESI): m/z¼331 (MHþ), 353
(MNaþ); HRMS: calculated for C13H10F3N2O3S 331.0359 found
331.0357 (
d¼0.5 ppm).
Under argon atmosphere a dry Schlenk tube was charged with
sulfoximine 1a (0.10 g, 1.0 equiv, 0.5 mmol), aryl halide (0.19 g,
2.0 equiv, 1 mmol), CuI (46 mg, 0.5 equiv, 0.25 mmol), DMEDA
(21 mg,1 equiv, 0.5 mmol), Cs2CO3 (0.39 g, 2.5 equiv,1.25 mmol), and
degassed (or freshly distilled) toluene (2 mL). After heating to 110 ꢀC
for 3 h, the mixture was cooled to room temperature and neutralized
with aqueous HCl (10 mL at 1 M). The aqueous layer was extracted
with dichloromethane (3ꢂ20 mL). The combined organic layers were
dried over MgSO4, filtered, and concentrated under reduced pressure.
The residue was purified by preparative chromatography (SiO2,
pentane/diethyl ether, 9/1) to give 0.14 g (97%) of3a as ayellow liquid.
4.3.6. N-((p-Ethyloxycarbonyl)phenyl) phenyl trifluoromethyl sul-
foximine (3g). Brown powder, mp: 63e65 ꢀC, yield 100%; 19F NMR
(188 MHz, CDCl3) (ppm)
(ppm)
d
ꢁ73.0 (3F, s); 1H NMR (300 MHz, CDCl3)
d
8.20 (2H, d, J¼7.3 Hz), 7.97 (2H, d, J¼8.9 Hz), 7.83e7.75 (1H,
m), 7.70e7.60 (2H, m), 7.30 (2H, d, J¼8.9 Hz), 4.35 (2H, q, J¼7.1 Hz),
1.37 (3H, t, J¼7.1 Hz); 13C NMR (75 MHz, CDCl3) (ppm)
d 166.2,
146.0, 135.6, 131.1, 130.8, 130.5, 129.6, 125.7, 132.5, 121.2 (q,
J¼338 Hz, CF3), 60.7, 14.2; MS (pos. ESI): m/z¼380 (MNaþ); HRMS:
calculated for C16H14F3NNaO3S 380.0539 found 380.0533
(d¼ꢁ2.8 ppm).
19F NMR (188 MHz, CDCl3) (ppm)
CDCl3) (ppm)
d
ꢁ72.6 (3F, s); 1H NMR (300 MHz,
d
8.19 (2H, d, J¼7.32 Hz), 7.78e7.70 (1H, m), 7.65e7.57
4.3.7. N-((o-Methoxy)phenyl) phenyl trifluoromethyl sulfoximine
(3h). Yellow oil, yield 99%; 19F NMR (188 MHz, CDCl3) (ppm)
(2H, m), 7.31e7.20 (4H, m), 7.10e7.03 (1H, m); 13C NMR (75 MHz,
CDCl3) (ppm)
d
141.1,135.4,131.7,130.5,129.5,129.2,124.0,123.9,121.4
d
ꢁ74.6 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.19 (2H, d,
(q, J¼339 Hz, CF3); MS (pos. ESI): m/z¼308 (MNaþ);HRMS: calculated
J¼7.5 Hz), 7.79e7.70 (1H, m), 7.67e7.58 (2H, m), 7.30 (1H, dd, J¼7.7,
for C13H10F3NNaOS 308.0327 found 308.0331 (
d¼ꢁ1.2 ppm).
1.7 Hz), 7.07 (1H, td, J¼7.7, 1.7 Hz), 6.95e6.87 (2H, m), 3.74 (3H, s);
13C NMR (75 MHz, CDCl3) (ppm)
d 152.4, 134.9, 133.1, 130.2, 130.0,
4.3.1. N-((o-Methyl)phenyl) phenyl trifluoromethyl sulfoximine
(3b). White powder, mp: 41e43 ꢀC, yield 98%; 19F NMR (188 MHz,
129.4, 125.1, 124.5, 121.0 (q, J¼335 Hz, CF3), 120.9, 111.7, 55.5; MS
(pos. ESI): m/z¼269 ([MNaꢁCF3]þ), 338 (MNaþ); HRMS: calculated
CDCl3) (ppm)
d
ꢁ73.3 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d
8.13
for C14H12F3NNaO2S 338.0433 found 338.0428 (
d
¼1.6 ppm).
(2H, d, J¼7.3 Hz), 7.70e7.62 (1H, m), 7.58e7.49 (2H, m), 7.23 (1H, dd,
J¼7.9 Hz, J¼1.2 Hz), 7.13e7.08 (1H, m), 7.02 (1H, td, J¼7.5, 1.7 Hz), 6.90
(1H, td, J¼7.3, 1.4 Hz) 2.32 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
4.3.8. N-((m-Methoxy)phenyl) phenyl trifluoromethyl sulfoximine
(3i). Pale yellow oil, yield 99%; 19F NMR (188 MHz, CDCl3) (ppm)

ꢀ
Y. Mace et al. / Tetrahedron 67 (2011) 7575e7580
7579
d
ꢁ72.6 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d
8.23 (2H, d,
(188 MHz, CDCl3) (ppm)
d
ꢁ73.8 (3F, s); 1H NMR (300 MHz, CDCl3)
J¼7.3 Hz), 7.83e7.74 (1H, m), 7.71e7.61 (2H, m), 7.21 (1H, t,
J¼8.1 Hz), 6.90 (1H, ddd, J¼7.7, 1.9, 1.0 Hz), 6.85 (1H, t, J¼2.1 Hz),
6.69 (1H, ddd, J¼8.3, 2.5, 0.8 Hz), 3.81 (3H, s); 13C NMR (75 MHz,
(ppm) d 8.20e8.10 (3H, m), 7.78e7.70 (1H, m), 7.65e7.54 (3H, m),
7.06 (1H, d, J¼8.1 Hz), 6.93e6.85 (1H, m); 13C NMR (75 MHz, CDCl3)
(ppm)
d 156.1, 148.1, 138.1, 135.2, 132.0, 130.4, 129.6, 120.6 (q,
CDCl3) (ppm)
d
160.2, 142.3, 135.4, 131.6, 130.5, 129.7, 129.5, 121.3 (q,
J¼332 Hz, CF3) 118.1, 117.2; MS (pos. ESI): m/z¼218 ([MHꢁCF3]þ),
J¼339 Hz, CF3), 116.3, 109.8, 109.7, 55.1; MS (pos. ESI): m/z¼269
287 (MHþ), 309 (MNaþ); HRMS: calculated for C12H10F3N2OS
([MNaꢁCF3]þ), 316 (MHþ), 338 (MNaþ); HRMS: calculated for
287.0460 found 287.0458 (
d¼0.8 ppm).
C14H12F3NNaO2S 338.0433 found 338.0433 (
d¼0.1 ppm).
4.3.16. N-(2-Thiophenyl)
phenyl trifluoromethyl
sulfoximine
4.3.9. N-((p-Methoxy)phenyl) phenyl trifluoromethyl sulfoximine
(3j). Yellow oil, yield 98%; 19F NMR (188 MHz, CDCl3) (ppm)
ꢁ72.2
(3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
8.23 (2H, d, J¼7.5 Hz),
(3r). Brown oil, yield 99%; 19F NMR (188 MHz, CDCl3) (ppm)
d
d
ꢁ71.7 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.25e8.18 (2H,
d
m), 7.85e7.77 (1H, m), 7.72e7.64 (2H, m), 6.88e6.81 (2H, m),
7.81e7.73 (1H, m), 7.69e7.60 (2H, m), 7.22(2H, d, J¼9.1 Hz), 6.86(2H, d,
6.75e6.71 (1H, m); 13C NMR (75 MHz, CDCl3) (ppm)
d 143.3, 135.7,
J¼9.1 Hz), 3.79 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
d
156.2, 135.3,
130.5, 129.6, 125.7121.3 (q, J¼340 Hz, CF3), 118.4, 117.3; MS (pos.
133.9,131.6,130.5,129.5,124.8,121.4 (q, J¼340 Hz, CF3),114.4, 55.3; MS
ESI): m/z¼245 ([MNaꢁCF3]þ), 292 (MHþ), 314 (MNaþ); HRMS:
(pos. ESI): m/z¼269 ([MNaꢁCF3]þ), 338 (MNaþ); HRMS: calculated for
calculated for C11H9F3NOS2 292.0072 found 292.0070 (
d
¼0.7 ppm).
C14H12F3NNaO2S 338.0433 found 338.0430 (
d¼0.8 ppm).
4.3.17. N-((o-Iodo)phenyl) phenyl trifluoromethyl sulfoximine
(3s). White powder, mp: 72e74 ꢀC, yield 70%; 19F NMR (188 MHz,
4.3.10. N-(Phenyl) (m-chloro)phenyl trifluoromethyl sulfoximine
(3l). Brown oil, yield 68%; 19F NMR (188 MHz, CDCl3) (ppm)
d
ꢁ72.3
CDCl3) (ppm)
d
ꢁ72.7 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
1
(3F, s); H NMR (300 MHz, CDCl3) (ppm)
d
8.22 (1H, s), 8.09 (1H, d,
d
8.38 (2H, d, J¼7.7 Hz), 7.84 (1H, dd, J¼7.9, 1.3 Hz), 7.81e7.74 (1H,
J¼7.9 Hz), 7.79e7.72 (1H, m), 7.60 (1H, t, J¼8.1 Hz), 7.37e7.22 (4H, m),
m) 7.70e7.62 (2H, m), 7.47 (1H, dd, J¼8.1, 1.4 Hz), 7.30e7.20 (1H, m),
7.16e7.08 (1H, m); 13C NMR (75 MHz, CDCl3) (ppm)
d
140.7, 135.9,
6.82 (1H, dt, J¼7.7, 1.5 Hz); 13C NMR (75 MHz, CDCl3) (ppm)
d 143.1,
135.6,133.5,130.7, 130.4,129.2, 128.6,124.1,123.9, 121.3 (q, J¼339 Hz,
139.3, 135.6, 131.4, 130.9, 129.6, 129.0, 125.2, 124.0, 122.8121.3 (q,
CF3); MS (pos. ESI, for 35Cl): m/z¼342 (MNaþ); HRMS: calculated for
J¼339 Hz, CF3), 95.4; MS (pos. ESI): m/z¼434 (MNaþ); HRMS: cal-
C13H395ClF3NNaOS 341.9938 found 341.9939 (
d¼ꢁ0.3 ppm).
culated for C13H9F3INNaOS 433.9294 found 433.9293 (
d
¼0.2 ppm).
4.3.11. N-(Phenyl) (p-chloro)phenyl trifluoromethyl sulfoximine
(3m). Brown powder, mp: 81e83 ꢀC, yield 99%; 19F NMR (188 MHz,
4.3.18. N-8-Bromonaphthyl phenyl trifluoromethyl sulfoximine
(3t). Brown oil, yield 72%; 19F NMR (188 MHz, CDCl3) (ppm)
CDCl3) (ppm)
d
ꢁ72.5 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d
ꢁ73.4 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.40 (2H, d,
d
8.16 (2H, d, J¼8.9 Hz), 7.63 (2H, d, J¼8.7 Hz), 7.35e7.22 (4H, m),
J¼7.7 Hz), 7.89 (1H, d, J¼7.3 Hz), 7.82e7.70 (2H, m), 7.70e7.55 (4H,
7.15e7.08 (1H, m); 13C NMR (75 MHz, CDCl3) (ppm)
d 142.7, 140.8,
m), 7.41e7.31 (1H, m), 7.30e7.21 (1H, m); 13C NMR (75 MHz, CDCl3)
132.0, 130.1, 129.9, 129.2, 124.0, 123.9, 121.3 (q, J¼339 Hz, CF3); MS
(ppm) d 142.0, 137.4, 137.0, 135.3, 133.6, 131.8, 130.8, 129.6, 128.8,
(pos. ESI, for 35Cl): m/z¼342 (MNaþ); HRMS: calculated for
126.7, 126.2, 126.0, 125.0, 121.6, 121.1 (q, J¼337 Hz, CF3), 117.5; MS
C13H395ClF3NNaOS 341.9938 found 341.9943 (
d
¼ꢁ1.5 ppm).
(pos. ESI, for 79Br): m/z¼367 ([MNaꢁCF3]þ), 436 (MNaþ); HRMS:
79
calculated for C17
H BrF3NNaOS 435.9589 found 435.9583
11
4.3.12. N-(Phenyl) (o-methyl)phenyl trifluoromethyl sulfoximine
(3n). Yellow oil, yield 99%; 19F NMR (188 MHz, CDCl3) (ppm)
(
d
¼1.5 ppm).
d
ꢁ72.3 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d 8.29 (1H, d,
Acknowledgements
J¼8.1 Hz), 7.63e7.55 (1H, m), 7.47e7.36 (2H, m), 7.32e7.20 (4H, m),
7.12e7.04 (1H, m), 2.84 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
Y.M. thanks Univers SUD PRES for financial support. Franc¸ ois
Metz (Rhodiacompany) is gratefully acknowledged for the gift of
fluorinated reagents, GwilhermEvano and Jean-Claude Blazejewski
for helpful discussions.
d
141.5, 141.4, 135.2, 133.8, 132.8, 131.1, 129.2, 127.0, 123.8, 123.7,
121.5 (q, J¼320 Hz, CF3), 21.3; MS (pos. ESI): m/z¼322 (MNaþ);
HRMS: calculated for C14H12F3NNaOS 322.0489 found 322.0489
(d
¼0.2 ppm).
Supplementary data
4.3.13. N-(Phenyl) (p-methyl)phenyl trifluoromethyl sulfoximine
(3o). Yellow powder, mp: 63e65 ꢀC, yield 99%; 19F NMR (188 MHz,
Copies of 1H, 13C, and 19F NMR for all new compounds. CCDC
816760 contains the supplementary crystallographic data for this
paper. These data can be obtained free of charge from The Cam-
bridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/
data_request/cif. Supplementary data associated with this article
can be found, in the online version, at doi:10.1016/j.tet.2011.07.060.
CDCl3) (ppm)
d
ꢁ72.8 (3F, s); 1H NMR (300 MHz, CDCl3) (ppm)
d
8.07 (2H, d, J¼7.3 Hz), 7.40 (2H, d, J¼8.1 Hz), 7.32e7.20 (4H, m),
7.10e7.03 (1H, m), 2.45 (3H, s); 13C NMR (75 MHz, CDCl3) (ppm)
d
146.9, 141.3, 130.5, 130.2, 129.1, 128.5, 124.0, 123.7, 121.4 (q,
J¼339 Hz, CF3), 21.7; MS (pos. ESI): m/z¼322 (MNaþ); HRMS: cal-
culated for C14H12F3NNaOS 322.0484 found 322.0482 (
d¼0.6 ppm).
References and notes
4.3.14. N-(Phenyl) phenyl nonafluorobutyl sulfoximine (3p). Brown
oil, yield 98%; 19F NMR (188 MHz, CDCl3) (ppm)
d
ꢁ81.3 (3F, m),
1. (a) Johnson, C. R. Acc. Chem. Res. 1973, 6, 341e347; (b) Pyne, S. G. Sulfur Rep.
1999, 21, 281e334; (c) Reggelin, M.; Zur, C. Synthesis 2000, 1e64.
ꢁ107.1 (2F, m), ꢁ120.9 (2F, m), ꢁ126.5 (2F, m); 1H NMR (300 MHz,
2. Selected examples: (a) Pyne, S. G.; Dong, Z.; Skelton, B. W.; White, A. H. J. Org.
Chem. 1997, 62, 2337e2343; (b) Reggelin, M.; Heinrich, T. Angew. Chem., Int. Ed.
1998, 37, 2883e2886; (c) Bosshammer, S.; Gais, H.-J. Synthesis 1998, 919e927;
(d) Paquette, L. A.; Gao, Z.; Ni, Z.; Smith, G. F. J. Am. Chem. Soc. 1998, 120,
2543e2552; (e) Harmata, M.; Pavri, N. Angew. Chem., Int. Ed. 1999, 38,
2419e2421; (f) Bolm, C.; Kesselgruber, M.; Muniz, K.; Raabe, G. Organometallics
2000, 19, 1648e1651; (g) Reddy, R. R.; Gais, H.-J.; Woo, C.-W.; Raabe, G. J. Am.
Chem. Soc. 2002, 124, 10427e10434.
CDCl3) (ppm)
d
8.18 (2H, d, J¼7.7 Hz), 7.75e7.67 (1H, m), 7.63e7.55
(2H, m), 7.35e7.18 (4H, m), 7.11e7.02 (1H, m); 13C NMR (75 MHz,
CDCl3) (ppm)
d 141.2, 135.2, 130.5, 129.3, 129.1, 123.9, 120.9, 117.8;
MS (pos. ESI): m/z¼239 ([MNaꢁC4F9]þ), 458 (MNaþ); HRMS: cal-
~
culated for C16H10F9NNaOS 458.0232 found 458.0232 (
d¼0.0 ppm).
3. (a) Harmta, M. Chemtracts 2003, 16, 660e666; (b) Okamura, H.; Bolm, C. Chem.
Lett. 2004, 33, 482e487; (c) Sedelmeier, J.; Hammerer, T.; Bolm, C. Org. Lett.
2008, 10, 917e920; (d) Lu, S.-M.; Bolm, C. Adv. Synth. Catal. 2008, 350,
4.3.15. N-(2-Pyridinyl)
phenyl
trifluoromethyl
sulfoximine
(3q). White powder, mp: 107e109 ꢀC, yield 98%; 19F NMR

ꢀ
Y. Mace et al. / Tetrahedron 67 (2011) 7575e7580
7580
1101e1105; (e) Frings, M.; Bolm, C. Eur. J. Org. Chem. 2009, 4085e4090; (f)
Frings, M.; Atodiresei, I.; Wang, Y.; Runsink, J.; Raabe, G.; Bolm, C. Chem.dEur. J.
2010, 16, 4577e4587.
11. For reviews see: (a) Ley, S. V.; Thomas, A. W. Angew. Chem., Int. Ed. 2003, 42,
5400e5449; (b) Evano, G.; Blanchard, N.; Toumi, M. Chem. Rev. 2008, 108,
3054e3131; (c) Monnier, F.; Taillefer, M. Angew. Chem., Int. Ed. 2009, 48,
6954e6971.
12. Collman, J. P.; Zhong, M.; Zhang, C.; Costanzo, S. J. Org. Chem. 2001, 66,
7892e7897.
4. Selected examples: (a) Mock, W. L.; Tsay, J.-T. J. Am. Chem. Soc. 1989, 111,
4467e4472; (b) Mock, W. L.; Zhang, J. Z. J. Biol. Chem. 1991, 266, 6393e6400; (c)
Harvision, P. J.; Kalman, T. I. J. Med. Chem. 1992, 35, 1227e1233; (d) McDonald, I.
A.; Nyce, P. L.; Ku, G. S.; Bowlin, T. L. Bioorg. Med. Chem. Lett. 1993, 3, 1717e1722;
(e) Dolle, R. E.; McNair, D. Tetrahedron Lett. 1993, 34, 133e136; (f) Kiwanishi, H.;
Morimoto, H.; Nakano, T.; Miyajima, T.; Oda, K.; Takeda, K.; Yano, S.; Hirano, N.;
13. Antilla, J. C.; Klapars, A.; Buchwald, S. L. J. Am. Chem. Soc. 2002, 124,
11684e11688.
14. Zhang, H.; Cai, Q.; Ma, D. J. Org. Chem. 2005, 70, 5164e5173 and references cited.
15. Klapars, A.; Huang, X.; Buchwald, S. L. J. Am. Chem. Soc. 2002, 124, 7421e7428.
16. (a) Dehli, J. R.; Bolm, C. Adv. Synth. Catal. 2005, 347, 239e242; (b) Moessner, C.;
Bolm, C. Org. Lett. 2005, 7, 2667e2669; (c) Sedelmeier, J.; Bolm, C. J. Org. Chem.
2005, 70, 6904e6906; (d) Correa, A.; Bolm, C. Adv. Synth. Catal. 2007, 349,
2673e2676; (e) Larsson, P.-F.; Correa, A.; Carril, M.; Norrby, P.-O.; Bolm, C.
Angew. Chem., Int. Ed. 2009, 48, 5691e5693; (f) Miyasaka, M.; Hirano, K.; Satoh,
T.; Kowalczyk, R.; Bolm, C.; Miura, M. Org. Lett. 2011, 13, 359e361.
17. Strieter, E. R.; Blackmond, D. G.; Buchwald, S. L. J. Am. Chem. Soc. 2005, 127,
4120e4121.
€
Tsujihara, K. Heterocycles 1998, 49, 169e180; (g) Bolm, C.; Muller, D.; Dalhoff, C.;
Hackenberger, C. P. R.; Weinhold, E. Bioorg. Med. Chem. Lett. 2003, 13, 3207e3211.
5. (a) Yagupol’skii, L. M. J. Fluorine Chem. 1987, 36, 1e28; (b) Terrier, F.; Magnier, E.;
Kizilian, E.; Wakselman, C.; Buncel, E. J. Am. Chem. Soc. 2005, 127, 5563e5571.
€
6. Kirsch, P.; Lenges, M.; Kuhne, D.; Wanczek, K.-P. Eur. J. Org. Chem. 2005, 797e802.
7. (a) Noritake, S.; Shibata, N.; Nakamura, S.; Toru, T.; Shiro, M. Eur. J. Org. Chem.
2008, 3465e3468; (b) Nomura, Y.; Tokunaga, E.; Shibata, N. Angew. Chem., Int.
Ed. 2011, 50, 1885e1889.
8. (a) Zhang, W.; Wang, F.; Hu, J. Org. Lett. 2009, 11, 2109e2112; (b) Zhang, W.;
Huang, W.; Hu, J. Angew. Chem., Int. Ed. 2009, 48, 9858e9861.
9. Urban, C.; Cadoret, F. J.; Blazejewski, J.-C.; Magnier, E. Eur. J. Org. Chem. 2011.
doi:10.1002/ejoc.201100503
18. Very recently, the efficient palladium-catalysed N-arylation of non-fluorinated
sulfoximines with aryl chlorides has been published: Yongpruksa, N.; Calkins,
N. L.; Harmata, M. Chem. Commun. 2011, 7665e7667.
ꢀ
10. Mace, Y.; Urban, C.; Pradet, C.; Marrot, J.; Blazejewski, J.-C.; Magnier, E. Eur. J.
19. For ortho effect see: Coste, A.; Toumi, M.; Wright, K.; Razafimahaleo, V.; Couty,
Org. Chem. 2009, 3150e3153.
F.; Marrot, J.; Evano, G. Org. Lett. 2008, 10, 3841e3844 and references cited.