Palladium nanoparticles catalyzed aroylation of: NH -sulfoximines with aryl iodides

Article abstract of DOI:10.1039/c6ra05334c

A novel approach towards aroylation of NH-sulfoximines using Pd nanoparticles stabilized by a binaphthyl backbone (Pd-BNP) has been developed. This synthetic protocol involves the Pd-BNP promoted carbon monoxide insertion of aryl iodides to form an aroyl intermediate which further reacts with NH-sulfoximines to form N-aroyl sulfoximine derivatives in good to excellent yields. The Pd-BNP catalyst was recovered and reused up to six times.

Full text of DOI:10.1039/c6ra05334c

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Palladium nanoparticles catalyzed aroylation of
NH-sulfoximines with aryl iodides†
Cite this: RSC Adv., 2016, 6, 37226
*
Nidhi Sharma and Govindasamy Sekar
A novel approach towards aroylation of NH-sulfoximines using Pd nanoparticles stabilized by a binaphthyl
backbone (Pd-BNP) has been developed. This synthetic protocol involves the Pd-BNP promoted carbon
monoxide insertion of aryl iodides to form an aroyl intermediate which further reacts with NH-
sulfoximines to form N-aroyl sulfoximine derivatives in good to excellent yields. The Pd-BNP catalyst
was recovered and reused up to six times.
Received 29th February 2016
Accepted 2nd April 2016
DOI: 10.1039/c6ra05334c
www.rsc.org/advances
Sulfoximines act as a template for the construction of key
Recently, several attempts have been made to overcome the
intermediates which can be utilized for the synthesis of above mentioned limitations. In 2013, Bolm et al., developed
heterocyclic compounds.1 The applications of sulfoximines-the copper catalyzed oxidative N-acylation of sulfoximine with
mono aza analogue of sulfones, have been explored tremen- aldehyde.11a The same group also developed another protocol
dously in recent years in many areas of modern chemistry. For using methylarenes as aroylating agent.12a Very recently, metal
example, sulfoximines have been used in agriculture and and metal free N-acylation of sulfoximine by employing ben-
medicinal chemistry,2 and as chiral ligands and auxillaries in zaldehyde11a,b and methyl arenes12b–d as precursors have been
asymmetric synthesis.3 The NH group of NH-sulfoximine is very developed (Scheme 1).
labile towards various functionalizations such as N-alkylation,4
The carbonylation reaction using transition metal catalyst,
N-arylation,5 N-alkynylation,6 N-vinylation,7 etc.8,9 One of the particularly palladium catalyst represents an important tool for
important functionalization is N-aroylation of NH-sulfoximine. introduction of carbonyl group in large number of organic
Traditionally, pre-activated benzoyl chloride or aromatic molecules.13 The carbonylation reactions such as amino-
carboxylic acids were used for N-aroylation of sulfoximines.10 carbonylation, alkoxycarbonylation and phenoxycarbonylation
However, these methods suffer from the drawbacks such as are well explored in the literature using homogeneous and
generating large amount of by-products and tedious procedure heterogeneous catalyst.14 However, sulfoximinocarbonylation of
for the purication of the compound.
aryl halides, which represents aroylation of NH-sulfoximines
using carbon monoxide as a source for in situ formation of aroyl
intermediate, is yet to develop. Also, there is need to develop
alternate strategies, so the problems associated with recovery
and reusability of the catalyst can be sorted out. Due to these
reasons, a lot of progress is going on to utilize the heteroge-
neous catalysis for various synthetic transformations.15
Encouraged by the excellent activity of our binaphthyl stabilized
Pd-nanoparticles (Pd-BNP), in a wide range of synthetic trans-
formations16 such as C–C bond formation reactions, cyanation
of aryl iodides, polyolen synthesis, aminocarbonylation of aryl
iodides with amines,14e herein, for the rst time, we report Pd-
BNP catalyzed aroylation of NH-sulfoximine from readily avail-
able carbon monoxide, aryl iodides and NH-sulfoximine under
mild reaction conditions (Scheme 2).
Scheme 1 Reported synthetic approaches for aroylation of NH-
sulfoximines.
Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600 036,
India. E-mail: gsekar@iitm.ac.in; Fax: +91 44 2257 4202; Tel: +91 44 2257 4229
† Electronic supplementary information (ESI) available. See DOI:
10.1039/c6ra05334c
Scheme 2 Aroylation of NH-sulfoximine using Pd-BNP.
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and meta-substituted aryl iodides (3a–3h and 3k–3v), ortho
substituted aryl iodides (3i–3j and 3w–3z) and sterically
hindered aryl iodide (3ab) gave good yield for the corresponding
products. When bromo- or chloro-substituted aryl iodides were
used, selectively N-aroylation was taken place and excellent
yield of the corresponding products were isolated (3s–3w).
When para- and ortho-acetyl protected iodophenol were
employed as aryl iodides, the N-aroylated products (3z and 3aa)
were isolated in 87% and 88% yield respectively. But when 2-
iodophenol and 4-iodophenol were used, 62% and 66% isolated
yield of 3z and 3aa were obtained. However, when heteroaryl
iodides such as 2-iodothiophen and 3-iodo-1-methyl-1H-indole
were used, even trace amount of product formation was not
observed (3ac and 3ad) under optimized conditions. Increasing
temperature and catalytic loading with longer reaction time (2
mol% Pd-BNP, 2 equiv. K2CO3, and 72 h at 110 ꢀC) did not help
to get the desired products. Aryl bromides such as 4-bromo
toluene and 4-bromo anisole were also tested for N-aroylation of
2a. Under the optimized conditions, these substrates remain
unreactive, but at high temperature and more catalytic loading
(2 mol% Pd-BNP, 2 equiv. K2CO3, 24 h at 110 ꢀC) 23% and 26%
yield for the N-aroylated products 3a and 3c were isolated
respectively and remaining 60–70% corresponding aryl
bromides were recovered.
Results and discussion
Initial investigation was started using 4-iodotoluene 1a and S-
methyl-S-phenyl-sulfoximine 2a as model substrates. The reac-
tion of 1a with 2a in presence of 2 mol% Pd-BNP catalyst, 2
equiv. of Na2CO3 in dry toluene at 110 ꢀC under CO balloon
(balloon pressure) yielded 72% of the desired N-aroylated
product 3a (Table 1, entry 1).
Different bases were employed to improve the efficacy of this
synthetic transformation (entries 1–3). K2CO3 was proved to be
the best base and provided 92% yield for the product 3a (entry
3). Further, the reaction was studied with respect of tempera-
ture and solvent employing K2CO3 as base (entries 4–9). Reac-
tion proceeded smoothly in DMF at 80 ꢀC and gave the product
in 91% yield within 7 h (entry 8). Varying the quantity of base, 2a
and catalyst showed that 1 equivalent of K2CO3, 1.5 equivalents
of 2a and 1 mol% Pd-BNP catalyst were effective and provided
excellent yield of 3a (entry 14). N-Aroylation of 2a did not
proceed in absence of Pd-BNP catalyst which showed that the
Pd-BNP catalyst was necessary for carbonylation of 2a (entry 15).
26% yield was isolated, when the reaction was performed in
absence of K2CO3 (entry 17).17,20
Having identied the optimized reaction conditions, the
applicability of this synthetic transformation was investigated
(Tables 2 and 3). First, the reactions between different
substituted aryl iodides 1 with 2a were tested (Table 2). Electron-
withdrawing as well as electron-donating functional groups in
aromatic ring of aryl iodides were well tolerated (3a–3ab). Para-
Furthermore, 4-iodo toluene 1a was further treated with
different NH-sulfoximines 2 under the optimized reaction
conditions and led to the formation of different products (3ae–
3am) in 63–95% isolated yields (Table 3). Electron donating
Table 1 Optimization of various reaction parametersa
Entry
Pd-BNP (mol%)
Base (equiv.)
Solvent
Temp. (ꢀC)
Time (h)
Yieldb (%)
1
2
3
4
5
6
7
8
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
1.0
1.0
1.0
—
Na2CO3 (2)
NaOtBu (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (2)
K2CO3 (1.5)
K2CO3 (1.0)
K2CO3 (0.5)
K2CO3 (1.0)
K2CO3 (1.0)
K2CO3 (1.0)
K2CO3 (1.0)
—
PhMe
PhMe
PhMe
DMF
Dioxane
PhMe
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
110
110
110
110
100
100
100
80
60
80
80
80
26
24
24
5
15
48
7
7
19
7
72
21
92
91
45
60
89
91
67
90
92
59
93
94c
77d
NRe
26
9
10
11
12
13
14
15
16
17
8
24
10
10
12
24
24
80
80
80
80
1.0
80
a
b
Reaction conditions: 0.5 mmol of 1a, 1.0 mmol of 2a, 3 mL of solvent and 10.6 mg Pd-BNP (10 wt% by ICP-OES analysis). Isolated yield. c 1.5
equiv. of 2a was used. d 1.2 equiv. of 2a was used. e NR ¼ no reaction.
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Table 2 Pd-BNP catalyzed N-aroylation of sulfoximine 2a with aryl Table 3 Pd-BNP catalyzed N-aroylation of sulfoximines 2 with 1aab
iodides 1ab
a
Reaction conditions: 0.5 mmol of 1a, 0.75 mmol of 2, 1 mL DMF.
b
Isolated yield. c Iodobenzene was used.
Scheme 3 Scalability of aroylation of NH-sulfoximine using Pd-BNP.
Scheme 4 Transformation of 3a to 4a.
To increase the application of the N-aroylated protocol,
a large scale reaction was conducted employing 1.5 g (6.88
mmol) of 4-iodotoluene 1a with 2a under the standard reaction
conditions. N-aroylation reaction proceeded smoothly and 95%
isolated yield for 3a was obtained (Scheme 3).
a
Reaction conditions: 0.5 mmol of 1, 0.75 mmol of 2a, 1 mL DMF.
b
d
c
Isolated yield. 4-Bromo toluene was used as aryl halide at 110 ꢀC.
e
4-Bromo anisole was used as aryl halide at 110 ꢀC. 2-Iodophenyl
acetate was used. f 4-Iodophenyl acetate was used.
N-Aroylated sulfoximine 3a was readily converted to 4a by
using Lawesson's reagent, which can also be used as ligand for
achiral and chiral organic synthesis (Scheme 4).
Importantly, Pd-BNP catalyst can be easily recovered and
reused by centrifugation. Also, the recovered Pd-BNP catalyst
shows high catalytic activity up to four cycles, but catalytic
activity was slightly reduced when h or further cycle was
tested as shown in Fig. 1. HRTEM images of Pd-BNP catalyst
before and aer sixth catalytic cycle showed that average
particles size of Pd-BNP particles are 5–8 nm (Fig. 2).
functional group substituted NH-sulfoximines; S-methyl-S-(4-
methylphenyl)- and S-methyl-S-(4-methoxyphenyl)-NH-sulfox-
imines provided excellent yields (95%) for the N-aroylated
products (3ae and 3af) compared to electron withdrawing
functional group substituted NH-sulfoximines (3ag–3ak). S-
ethyl-S-phenyl-NH-sulfoximine also afforded corresponding
product 3al in excellent yield. Similarly, when aliphatic NH-
sulfoximine, 1-iminotetrahydro-1H-1l6-thiophene 1-oxide, was
used, corresponding product 3am was isolated in 63% yield.
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Fischer Scientic, India Pvt. Ltd. Reactions were monitored by
thin-layer chromatography (TLC) using Merck silica gel 60 F254
precoated plates (0.25 mm) and visualized by UV uorescence
quenching using appropriate mixture of ethyl acetate and
hexanes. Silica gel (particle size: 100–200 mesh) was purchased
from Avra and used for column chromatography using hexanes
and ethyl acetate mixture as eluent. K2PdCl4 (98%) was obtained
from Sigma-Aldrich and used directly as received. Various aryl
iodides and substituted suldes were purchased from Alfa-aesar
and Sigma-Aldrich Company. (ꢁ)-BINAM was purchased from
Gerchem Pvt. Ltd, Hyderabad, India and used as received. Other
chemicals like NaBH4 were purchased from Spectrochem Pvt.
Ltd., Mumbai, India and K2CO3, Na2CO3, KOH were purchased
from Fischer Scientic, India Pvt. Ltd. 1,10-Binaphthyl-2,20-bis-
(diazoniumtetrauoroborate) was prepared using literature
procedure.19 NH-sulfoximines were prepared from commercially
available sulphides using literature reported procedure.10f Nano
pure water was obtained from Milli-Q Integral Water Purication
System. All the reactions were carried out in temperature
Fig. 1 Recyclability of Pd-BNP in aroylation of sulfoximine 2a.
1
controlled IKA magnetic stirrers. H, 13C and 19F NMR spectra
1
were recorded on a Bruker 400 and 500 instruments. H NMR
spectra were reported relative to Me4Si (d 0.0 ppm) or residual
CDCl3 (d 7.26 ppm) and DMSO-d6 (d 2.50 ppm). 13C NMR were
reported relative to CDCl3 (d 77.16 ppm) and DMSO-d6 (d 39.51
ppm). 19F NMR were reported relative to C6F6 (d ꢂ164.9 ppm).
FTIR spectra were recorded on a Nicolet 6700 spectrometer and
were reported in frequency of absorption (cmꢂ1). High resolution
mass spectra (HRMS) were recorded on Q-Tof Micro mass
spectrometer.
Fig. 2 HRTEM images of Pd-BNP before (a) and after sixth catalytic
cycle (b).
Hg poisoning test18 was also conducted to support our
observation that the reaction was catalyzed by Pd-BNP nano-
catalyst not by the leached soluble Pd. Pd-BNP catalyst (1 mol%)
and mercury (30 equivalents) was rst stirred at room temper-
ature for 2 hours, then the other reagents-1a (0.5 mmol), 2a
(0.75 mmol) and K2CO3 (1 equivalent) were added and stirred
for another 10 h using CO balloon at 80 ꢀC. Complete inhibition
of the product formation was observed.17
General procedure for the preparation of Pd-BNP catalyst16a
In a dry 250 mL round bottom ask, potassium tetrachloro
palladate (K2PdCl4) (326.5 mg, 1.0 mmol) was added to 50 mL
nano pure water. Followed by the addition of 1,10-binaphthyl-
2,20-bis(diazoniumtetrauoroborate) (482.1 mg, 1.0 mmol).
Aer that toluene (50 mL) was added and vigorously stirred at
room temperature for 1 h. Reaction mixture was turned into
orange-brown colour which indicates the complexation of
palladium with diazonium salt. Aer 1 hour, NaBH4 (226.9 mg,
6.0 mmol) in nano pure water (2 mL) was added drop by drop
for 15 min to the reaction mixture at room temperature. Orange
colour of the reaction mixture change to dark greenish black
signies the formation of Pd-BNP catalyst and stirring
continued for another 2 h. The toluene layer was separated and
washed with 0.5 M aq. sulphuric acid (3 ꢃ 50 mL) and 0.5 M
NaHCO3 solution (3 ꢃ 50 mL). Then the solvent was completely
evaporated under rotary evaporator. Then the resultant solid
catalyst were suspended in ethanol and sonicated for 30 min
followed by centrifuged (4500 rpm) for 30 min at room
temperature. Ethanol was decanted and dried under in vacuo to
yield the Pd-binaphthyl nanoparticles (Pd-BNP, 384 mg, 10 wt%
Pd, ICP-OES analysis) and characterized.
Conclusions
In conclusion, we have developed an efficient and novel protocol
toward aroylation of NH-sulfoximines by using well dened semi-
heterogeneous palladium nanoparticles (Pd-BNP) as catalyst.
Various N-aroylated sulfoximines were synthesized under mild
conditions by utilizing CO with aryl iodides as in situ source of
aroyl intermediate and facilitated products in good to excellent
yields. The Pd-BNP catalyst was recovered up to six times. The
present study will provide a new alternate pathway for the
construction of various N-aroylated sulfoximines. Further inves-
tigation toward extending the applications of reusable Pd-BNP
catalyst in related transformations are under progress.
Experimental sections
General consideration
General procedure for aroylation of NH-sulfoximines
All reactions were carried out in reaction tubes under CO atmo- Aryl iodide (0.5 mmol), NH-sulfoximine (0.75 mmol), Pd-BNP
sphere. All the solvents used for the reactions were obtained from catalyst (5.3 mg, 1 mol%) and K2CO3 (69 mg, 1 equiv.) was
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taken in an oven dried reaction tube equipped with magnetic (m/z): [MNa]+ calcd for C15H15NO3SNa: 312.0665; found:
pellet and capped with septum. The reaction tube was evacu- 312.0664.
ated and DMF (1 mL) was added. Reaction tube was again
N-(3,4,5-Trimethoxybenzoyl)-S-methyl-S-phenyl sulfoximine
ꢀ
evacuated and relled with CO using balloon and stirred at 80 (3d). Yield 84%; 146.7 mg; white solid, mp 140–142 C; Rf 0.4
ꢀC until completion of the reaction and monitored by TLC. Aer (50% ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm)
completion of the reaction, the reaction mixture was then d 8.04 (d, J ¼ 7.6 Hz, 2H), 7.69 (t, J ¼ 7.2 Hz, 1H), 7.61 (t, J ¼ 7.2
allowed to cool to room temperature and extracted with ethyl Hz, 2H), 7.44 (s, 2H), 3.89 (s, 9H), 3.46 (s, 3H); 13C NMR (CDCl3,
acetate (3 ꢃ 10 mL), followed by brine solution. Then the 100 MHz, ppm) d 173.8, 152.8, 141.9, 139.2, 133.9, 131.0, 129.8,
organic phase was dried over Na2SO4 and concentrated in 127.2, 106.9, 61.0, 56.4, 44.5; FTIR (KBr) 3072, 3008, 2924, 1623,
vacuum. The resulting reaction mixture was puried by column 1582, 1503, 1455, 1413, 1333, 1222, 1124, 994, 868, 767 cmꢂ1
chromatography on silica gel (hexanes : ethyl acetate) to get N- HRMS (m/z): [MNa]+ calcd for C17H19NO5SNa: 372.0981; found:
;
aroylated sulfoximine product 3.
372.0989.
N-(3,5-Dimethoxybenzoyl)-S-methyl-S-phenyl
N-(4-Methylbenzoyl)-S-methyl-S-phenyl sulfoximine (3a).12b
sulfoximine
4-Iodotoluene 1a (109.0 mg, 0.5 mmol), S-methyl-S-phenyl- (3e). Yield 88%, 140.5 mg; white solid, mp 88–90 ꢀC; Rf 0.6 (50%
sulfoximine 2a (116.4 mg, 0.75 mmol), Pd-BNP catalyst (5.3 ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.12
mg, 1 mol%) and K2CO3 (69 mg, 1 equiv.) was taken in an oven (d, J ¼ 8.8 Hz, 2H), 8.04–8.00 (m, 2H), 7.68 (tt, J ¼ 7.2 Hz, 1.2 Hz,
dried reaction tube equipped with magnetic pellet and capped 1H), 7.64–7.57 (m, 2H), 7.33 (d, J ¼ 2.4 Hz, 2H), 6.61 (t, J ¼ 2.4
with septum. The reaction tube was evacuated and DMF (1 mL) Hz, 1H), 3.82 (s, 6H), 3.45 (s, 3H); 13C NMR (CDCl3, 100 MHz,
was added. Reaction tube was again evacuated and relled with ppm) d 174.0, 160.6, 139.1, 137.8, 133.9, 129.8, 127.3, 107.2,
CO using balloon and stirred at 80 ꢀC up to 10 h and monitored 105.1, 55.7, 44.5; FTIR (KBr) 3064, 3007, 2959, 1628, 1552, 1449,
by TLC. Aer completion of the reaction, the reaction mixture 1259, 1154, 857, 807, 753, 738, 685 cmꢂ1; HRMS (m/z): [MNa]+
was then allowed to cool to room temperature and extracted calcd for C16H17NO4SNa: 342.0861; found: 342.0869.
with ethyl acetate (3 ꢃ 10 mL), followed by brine solution. Then
N-(3,5-Dimethylbenzoyl)-S-methyl-S-phenyl
sulfoximine
the organic phase was dried over Na2SO4 and concentrated in (3f).12c Yield 83%; 119.3 mg; yellow oil; Rf 0.3 (30% ethylacetate
1
vacuum. The resulting reaction mixture was puried by column in hexanes); H NMR (CDCl3, 400 MHz, ppm) d 8.05 (d, J ¼ 7.6
chromatography on silica gel (hexanes: ethyl acetate) to get N- Hz, 2H), 7.78 (s, 2H), 7.68 (t, J ¼ 7.2 Hz, 1H), 7.61 (t, J ¼ 7.2 Hz,
aroylated sulfoximine product 3a.
2H), 7.15 (s, 1H), 3.46 (s, 3H), 2.35 (s, 6H); 13C NMR (CDCl3, 100
ꢀ
Yield 93%; 128.5 mg; white solid, mp 166–168 C [lit. 168– MHz, ppm) d 174.8, 139.3, 137.8, 135.6, 134.0, 133.9, 129.8,
169 ꢀC];11b Rf 0.6 (40% ethylacetate in hexanes); 1H NMR (CDCl3, 127.3, 44.6, 21.3; FTIR (CH2Cl2) 3061, 3012, 2924, 1626, 1561,
400 MHz, ppm) d 8.10–8.00 (m, 4H), 7.68 (tt, J ¼ 7.2 Hz, 1.2 Hz, 1447, 1316, 1226, 977, 863, 771, 752, 737, 684 cmꢂ1; HRMS (m/
2H), 7.64–7.57 (m, 2H), 7.21 (d, J ¼ 8.0 Hz, 2H), 3.46 (s, 3H), 2.40 z): [MNa]+ calcd for C16H17NO2SNa: 310.0874; found: 310.0856.
(s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 174.4, 142.8, 139.4,
N-(3-Methylbenzoyl)-S-methyl-S-phenyl sulfoximine (3g).
ꢀ
133.1, 129.8, 129.7, 128.9, 127.3, 44.5, 21.7; FTIR (KBr) 3061, Yield 85%; 116.2 mg; light yellow solid; mp 78–80 C; Rf 0.26
3019, 2923, 1623, 1609, 1570, 1445, 1313, 1282, 1219, 1136, 981, (30% ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm)
838, 756, 742, 685 cmꢂ1; HRMS (m/z): [MNa]+ calcd for C15H15
-
d 8.06 (d, J ¼ 7.6 Hz, 2H), 8.01–7.93 (m, 2H), 7.69 (t, J ¼ 7.2 Hz,
NO2SNa: 296.0718; found: 296.0710.
1H), 7.61 (t, J ¼ 7.2 Hz, 1H), 7.37–7.28 (m, 2H), 3.47 (s, 3H), 2.40
N-Benzoyl-S-methyl-S-pheny lsulfoximine (3b).11a Yield 83%; (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 174.6, 139.3, 137.9,
120.32 mg; white solid, mp 120–122 ꢀC [lit. 122–123 ꢀC];10f Rf 135.7, 133.9, 133.1, 130.1, 129.8, 128.1, 127.3, 126.8, 44.5, 21.5;
1
0.28 (30% ethylacetate in hexanes); H NMR (CDCl3, 400 MHz, FTIR (KBr) 3063, 3020, 2926, 1631, 1602, 1583, 1447, 1289, 1207,
ppm) d 8.20–8.14 (m, 2H), 8.10–8.03 (m, 2H), 7.69 (tt, J ¼ 7.2 Hz, 1125, 1088, 979, 862, 808, 748, 685 cmꢂ1; HRMS (m/z): [MNa]+
1.2 Hz, 1H), 7.65–7.58 (m, 2H), 7.51 (tt, J ¼ 7.2 Hz, 1.2 Hz, 1H), calcd for C15H15NO2SNa: 296.0718; found: 296.0706.
7.41 (t, J ¼ 7.2 Hz, 2H), 3.47 (s, 3H), 2.40 (s, 3H); 13C NMR
N-(3-Methoxybenzoyl)-S-methyl-S-phenyl sulfoximine (3h).
(CDCl3, 100 MHz, ppm) d 174.4, 139.2, 135.7, 133.9, 132.3, Yield 85%; 128.8 mg; light yellow solid; mp 92–94 ꢀC [lit. 91–92
129.8, 129.6, 128.2, 127.3, 44.5; FTIR (KBr) 3062, 3020, 2927, ꢀC];10f Rf 0.6 (50% ethylacetate in hexanes); 1H NMR (CDCl3, 400
1629, 1577, 1448, 1314, 1283, 1137, 99, 838, 734, 714, 698 cmꢂ1
;
MHz, ppm) d 8.05 (d, J ¼ 8.0 Hz, 2H), 7.79 (d, J ¼ 7.2 Hz, 1H),
HRMS (m/z): [MNa]+ calcd for C14H13NO2SNa: 282.0558; found: 7.73–7.65 (m, 2H), 7.61 (t, J ¼ 7.2 Hz, 2H), 7.32 (t, J ¼ 8.0 Hz, 1H),
282.0549.
7.06 (dd, J ¼ 8.0 Hz, 2.0 Hz, 1H), 3.84 (s, 3H), 3.46 (s, 3H); 13C
N-(4-Methoxybenzoyl)-S-methyl-S-phenylsulfoximine (3c).12c NMR (CDCl3, 100 MHz, ppm) d 174.2, 159.6, 139.2, 137.2, 133.9,
ꢀ
Yield 91%; 132.7 mg; white solid, mp 136–138 C [lit. 138–139 129.8, 128.1, 127.3, 122.2, 118.9, 113.9, 55.5, 44.5; FTIR (KBr)
ꢀC];11a Rf 0.6 (50% ethylacetate in hexanes); 1H NMR (CDCl3, 400 3064, 3010, 2928, 1627, 1581, 1286, 1219, 1092, 982, 806, 742,
MHz, ppm) d 8.12 (d, J ¼ 8.8 Hz, 2H), 8.05 (d, J ¼ 8.0 Hz, 2H), 685 cmꢂ1; HRMS (m/z): [MH]+ calcd for C15H15NO3SNa:
7.67 (t, J ¼ 7.2 Hz, 1H), 7.60 (t, J ¼ 7.2 Hz, 2H), 6.89 (d, J ¼ 8.8 Hz, 312.0667; found: 312.0663.
2H), 3. 85 (s, 3H), 3.45 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm)
N-(2-Methylbenzoyl)-S-methyl-S-phenyl sulfoximine (3i).10f
d 173.1, 163.1, 139.5, 133.8, 131.6, 129.8, 128.5, 127.3, 113.4, Yield 84%; 114.8 mg; light brown solid; mp 104–106 ꢀC [lit. 108–
55.5, 44.6; FTIR (KBr) 3065, 3010, 2728, 1627, 1597, 1581, 1448, 109 ꢀC];10f Rf 0.27 (40% ethylacetate in hexanes); 1H NMR
1311, 1288, 1218, 1092, 1043, 982, 861, 758, 685 cmꢂ1; HRMS (CDCl3, 400 MHz, ppm) d 8.09–8.03 (m, 3H), 7.69 (tt, J ¼ 7.6 Hz,
1.2 Hz, 1H), 7.65–7.59 (m, 2H), 7.34 (td, J ¼ 7.6 Hz, 1.6 Hz, 1H),
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7.25–7.18 (m, 2H), 3.43 (s, 3H), 2.60 (s, 3H); 13C NMR (CDCl3, 1405, 1277, 1221, 1137, 980, 843, 733, 685 cmꢂ1; HRMS (m/z):
100 MHz, ppm) d 176.7, 139.4, 139.2, 135.4, 133.9, 131.7, 131.1, [MH]+ calcd for C16H16NO3S: 302.0847; found: 302.0839.
130.7, 129.8, 127.3, 125.5, 44.6; FTIR (KBr) 3065, 3019, 2926,
1628, 1570, 1447, 1310, 1260, 1216, 1105, 979, 741, 662 cmꢂ1
N-(4-Cyanobenzoyl)-S-methyl-S-phenyl sulfoximine (3o).12c
Yield 74%; 105.2 mg; light yellow solid; mp 78–80 ꢀC [lit. 79–81
;
HRMS (m/z): [MH]+ calcd for C15H16NO2S: 274.0897; found: ꢀC];12c Rf 0.2 (30% ethylacetate in hexanes); 1H NMR (CDCl3, 400
274.0899.
MHz, ppm) d 8.24 (d, J ¼ 8.4 Hz, 2H), 8.04 (d, J ¼ 7.6 Hz, 2H),
N-(2-Methoxybenzoyl)-S-methyl-S-phenyl sulfoximine (3j). 7.75–7.67 (m, 3H), 7.66–7.60 (m, 2H), 3.49 (s, 3H); 13C NMR
Yield 84%; 124.4 mg; light yellow liquid; Rf 0.3 (50% ethyl- (CDCl3, 100 MHz, ppm) d 172.5, 139.6, 138.6, 134.3, 132.1,
acetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.12–8.06 130.1, 130.0, 127.2, 118.6, 115.5, 44.5; FTIR (KBr) 3064, 3020,
(m, 2H), 7.90 (dd, J ¼ 8.0 Hz, 2.0 Hz, 1H), 7.67 (tt, J ¼ 7.2 Hz, 1.2 2927, 2229, 1634, 1561, 1447, 1404, 1280, 980, 842, 769, 739, 685
Hz, 1H), 7.60 (t, J ¼ 7.2 Hz, 2H), 7.43–7.36 (m, 1H), 3.90 (s, 3H), cmꢂ1; [MH]+ calcd for C15H13N2O2S: 285.0697; found: 285.0699.
3.46 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 174.9, 158.8,
N-(4-Methylcarbonylesterbenzoyl)-S-methyl-S-phenyl sulfox-
139.3, 133.8, 132.5, 131.6, 129.7, 127.5, 126.3, 120.2, 112.2, 56.1, imine (3p).12c Yield 88%; 139.6 mg; white solid; mp 121–123 ꢀC
44.5; FTIR (KBr) 3065, 3010, 2928, 1629, 1582, 1448, 1319, 1219, [lit. 125–126 ꢀC];12c Rf 0.66 (50% ethylacetate in hexanes); 1H
1144, 979, 757, 733, 700 cmꢂ1; HRMS (m/z): [MH]+ calcd for NMR (CDCl3, 400 MHz, ppm) d 8.20 (d, J ¼ 8.8 Hz, 2H), 8.10–
C
15H16NO3S: 290.0845; found: 290.0853.
8.02 (m, 4H), 7.69 (tt, J ¼ 7.6 Hz, 1.2 Hz, 1H), 7.65–7.58 (m, 2H),
N-(4-Nitrobenzoyl)-S-methyl-S-phenyl sulfoximine (3k). Yield 3.92 (s, 3H), 3.48 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm)
86%; 130.6 mg; white solid; mp 126–128 ꢀC [lit. 128–130 ꢀC];12c d 173.4, 166.7, 139.6, 138.8, 134.1, 133.2, 129.9, 129.5, 129.4,
Rf 0.6 (50% ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, 127.2, 52.4, 44.5; FTIR (KBr) 3057, 3022, 2928, 1682, 1622, 1566,
ppm) d 8.30 (dt, J ¼ 9.2 Hz, 2.0 Hz, 2H), 8.23 (dt, J ¼ 9.2 Hz, 1.6 1499, 1446, 1287, 1217, 1136, 1090, 1016, 985, 835, 769, 742, 686
Hz, 1H), 8.07–8.02 (m, 2H), 7.73 (tt, J ¼ 7.2 Hz, 1.2 Hz, 2H), 7.65 cmꢂ1; HRMS (m/z): [MNa]+ calcd for C16H15NO4SNa: 318.0797;
(t, J ¼ 7.2 Hz, 2H), 3.50 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) found: 318.0799.
d 172.2, 150.2, 141.2, 138.5, 134.3, 130.5, 130.0, 127.2, 123.4,
N-(4-Fluorobenzoyl)-S-methyl-S-phenyl sulfꢀoximine (3q).
44.5; FTIR (KBr) 3068, 3019, 2927, 1632, 1599, 1522, 1349, 1285, Yield 91%; 126.2 mg; white solid; mp 128–130 C [lit. 128–129
1222, 981, 832, 735, 722 cmꢂ1; HRMS (m/z): [MNa]+ calcd for ꢀC];11a Rf 0.27 (30% ethylacetate in hexanes); H NMR (CDCl3,
1
C
14H12N2O4SNa: 327.0411; found: 327.0412.
500 MHz, ppm) d 8.22–8.13 (m, 2H), 8.04 (d, J ¼ 7.5 Hz, 2H), 7.69
N-(3-Nitrobenzoyl)-S-methyl-S-phenyl sulfoximine (3l).12c (t, J ¼ 7.5 Hz, 1H), 7.62 (t, J ¼ 7.5 Hz, 2H), 7.06 (t, J ¼ 8.5 Hz, 2H),
Yield 85%; 129.3 mg; light yellow solid; mp 103–105 ꢀC [lit. 108– 3.46 (s, 3H); 13C NMR (CDCl3, 125 MHz, ppm) d 173.3, 165.5 (d,
110 ꢀC];12c Rf 0.57 (50% ethylacetate in hexanes); 1H NMR JC–F ¼ 251.3 Hz), 138.9, 134.0, 132.0 (d, JC–F ¼ 10 Hz), 129.8,
(CDCl3, 400 MHz, ppm) d 8.98 (t, J ¼ 2.0 Hz, 1H), 8.45 (dt, J ¼ 8.0 127.2, 115.1 (d, JC–F ¼ 21.25 Hz), 44.5; 19F NMR (CDCl3, 470
Hz, 1.2 Hz, 1H), 8.37–8.32 (m, 1H), 8.08–8.32 (m, 2H), 7.72 (tt, J MHz, ppm) d ꢂ110.7; FTIR (KBr) 3066, 3022, 2929, 1626, 1600,
¼ 7.6 Hz, 1.2 Hz, 1H), 7.68–7.56 (m, 3H), 3.50 (s, 3H); 13C NMR 1504, 1448, 1150, 1137, 1089, 980, 769, 743 cmꢂ1; HRMS (m/z):
(CDCl3, 100 MHz, ppm) d 171.9, 148.3, 138.5, 137.6, 135.2, [MH]+ calcd for C14H13NO2SF: 278.0647; found: 278.0649.
134.3, 130.0, 129.3, 127.2, 126.7, 124.6, 44.6; FTIR (KBr) 3085,
N-(3-Fluorobenzoyl)-S-methyl-S-phenyl sulfoximine (3r).
3020, 2928, 1632, 1529, 1476, 1441, 1352, 1154, 1090, 981, 869, Yield 78%; 108.2 mg; white solid; mp 86–88 ꢀC [lit. 87–89 ꢀC];10f
727, 688 cmꢂ1; HRMS (m/z): [MNa]+ calcd for C14H12N2O4SNa: Rf 0.3 (30% ethylacetate in hexanes); 1H NMR (CDCl3, 500 MHz,
327.0411; found: 327.0419.
ppm) d 8.04 (d, J ¼ 7.5 Hz, 2H), 7.94 (d, J ¼ 8.0 Hz, 1H), 7.82 (d, J
N-(4-Triuorobenzoyl)-S-methyl-S-phenyl sulꢀfoximine (3m). ¼ 10.0 Hz, 1H), 7.70 (t, J ¼ 7.5 Hz, 1H), 7.62 (t, J ¼ 8.0 Hz, 2H),
Yield 78%; 127.7 mg; white solid; mp 100–102 C [lit. 102–104 7.41–7.34 (m, 1H), 7.20 (td, J ¼ 8.0 Hz, 2.0 Hz, 1H), 3.46 (s, 3H);
ꢀC];12c Rf 0.27 (40% ethylacetate in hexanes); H NMR (CDCl3, 13C NMR (CDCl3, 125 MHz, ppm) d 173.1, 162.7 (d, JC–F ¼ 245
1
500 MHz, ppm) d 8.27 (d, J ¼ 8.5 Hz, 2H), 8.05 (d, J ¼ 8.0 Hz, 2H), Hz), 138.8, 138.1 (d, JC–F ¼ 6.25 Hz), 134.1, 129.9, 129.7 (d, JC–F
¼
7.71 (t, J ¼ 8.0 Hz, 1H), 7.68–7.59 (m, 4H), 3.48 (s, 3H); 13C NMR 7.5 Hz), 127.3, 125.2 (d, JC–F ¼ 2.5 Hz), 119.2 (d, JC–F ¼ 21.25 Hz),
(CDCl3, 125 MHz, ppm) d 173.0, 138.9, 138.7, 134.2, 133.6 (q, JC–F 116.4 (d, JC–F ¼ 22.5 Hz), 44.5; 19F NMR (CDCl3, 470 MHz, ppm)
¼ 32.5 Hz), 129.90, 127.85, 127.2, 125.2 (q, JC–F ¼ 3.75 Hz), 124.0 d ꢂ116.5; FTIR (KBr) 3070, 3011, 2924, 1634, 1588, 1455, 1262,
(q, J ¼ 271.25 Hz), 44.5; 19F NMR (CDCl3, 470 MHz, ppm) 1109, 1067, 974, 751, 680 cmꢂ1; HRMS (m/z): [MH]+ calcd for
d ꢂ66.0; FTIR (KBr) 3062, 3020, 2922, 1628, 1579, 1449, 1407,
1315, 1285, 1199, 980, 862, 775, 704, 686 cmꢂ1; HRMS (m/z):
[MH]+ calcd for C15H13NO2SF3: 328.0617; found: 328.0609.
C
14H13NO2SF: 278.0646; found: 278.0653.
N-(4-Bromobenzoyl)-S-methyl-S-phenyl sulfoximine (3s).11b
ꢀ
Yield 73%; 123.5 mg; white solid; mp 114–116 C [lit. 117–118
1
N-(4-Acetylbenzoyl)-S-methyl-S-phenyl sulfoximine (3n).12c ꢀC];11b Rf 0.27 (30% ethylacetate in hexanes); H NMR (CDCl3,
ꢀ
Yield 83%; 125.1 mg; white solid; mp 118–120 C [lit. 120–122 400 MHz, ppm) d 8.08–7.99 (m, 4H), 7.69 (t, J ¼ 7.2 Hz, 1H), 7.62
ꢀC];12c Rf 0.55 (50% ethylacetate in hexanes); H NMR (CDCl3, (t, J ¼ 7.2 Hz, 2H), 7.54 (d, J ¼ 8.8 Hz, 2H), 3.46 (s, 3H); 13C NMR
1
400 MHz, ppm) d 8.23 (d, J ¼ 8.4 Hz, 2H), 8.09–8.03 (m, 2H), 7.99 (CDCl3, 100 MHz, ppm) d 173.4, 139.0, 134.7, 134.1, 131.4,
(d, J ¼ 8.8 Hz, 2H), 7.71 (t, J ¼ 7.6 Hz, 1H), 7.63 (t, J ¼ 8.0 Hz, 131.2, 129.9, 127.3, 44.5; FTIR (KBr) 3064, 3015, 2927, 1627,
2H), 3.49 (s, 3H), 2.63 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) 1586, 1567, 1446, 1395, 1284, 1220, 1137, 979, 835, 758, 744, 684
d 198.0, 173.4, 139.6, 138.9, 134.1, 129.9, 129.7, 128.1, 127.3, cmꢂ1
;
HRMS (m/z): [MNa]+ calcd for C14H12NO2SBrNa:
44.5, 27.0; FTIR (KBr) 3062, 3015, 2928, 1721, 1628, 1570, 1447, 359.9668; found: 359.9679.
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7.59 (m, 3H), 7.53 (td, J ¼ 7.6 Hz, 1.2 Hz, 1H), 3.51 (s, 3H); 13C
NMR (CDCl3, 100 MHz, ppm) d 173.2, 144.4, 138.0, 134.4, 133.5,
132.9, 130.7, 130.0, 129.9, 127.4, 123.6, 43.5; FTIR (CH2Cl2)
3068, 3024, 2956, 1626, 1575, 1477, 1357, 980, 778, 739, 690
cmꢂ1; HRMS (m/z): [MH]+ calcd for C14H13N2O4S: 305.0591;
found: 305.0599.
N-(2-Hydroxybenzoyl)-S-methyl-S-phenyl sulfoximine (3z).
Yield 87%; 119.8 mg; light brown viscous liquid; Rf 0.32 (30%
ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm)
d 11.85 (s, 1H), 8.09 (dd, J ¼ 7.6 Hz, 1.2 Hz, 1H), 8.03 (d, J ¼ 7.2
Hz, 2H), 7.71 (t, J ¼ 7.2 Hz, 1H), 7.62 (t, J ¼ 7.6 Hz, 2H), 7.39 (t, J
¼ 7.2 Hz, 1H), 6.91 (d, J ¼ 8.4 Hz, 1H), 6.85 (t, J ¼ 7.6 Hz, 1H),
3.46 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 178.2, 162.2,
138.4, 135.1, 134.3, 131.2, 130.0, 127.2, 118.7, 117.5, 44.8; FTIR
(KBr) 3487, 3062, 3021, 2928, 1626, 1590, 1222, 1070, 980, 757,
738, 702 cmꢂ1; HRMS (m/z): [MNa]+ calcd for C14H13NO3SNa:
298.0510; found: 298.0502.
N-(4-Chlorobenzoyl)-S-methyl-S-phenyl sulfoximine (3t).
ꢀ
Yield 74%; 108.7 mg; white solid; mp 114–116 C [lit. 114–116
1
ꢀC];12c Rf 0.26 (30% ethylacetate in hexanes); H NMR (CDCl3,
400 MHz, ppm) d 8.10 (tt, J ¼ 8.4 Hz, 2.4 Hz, 2H), 8.06–8.02 (m,
2H), 7.70 (t, J ¼ 7.2 Hz, 1H), 7.62 (t, J ¼ 7.2 Hz, 2H), 7.37 (td, J ¼
8.8 Hz, 2.0 Hz, 2H), 3.44 (s, 3H); 13C NMR (CDCl3, 100 MHz,
ppm) d 173.3, 139.0, 138.6, 134.2, 134.1, 131.1, 129.9, 128.4,
127.3, 44.5; FTIR (KBr) 3065, 3017, 2928, 1629, 1590, 1484, 1447,
1220, 1136, 1089, 980, 762, 743, 684 cmꢂ1; HRMS (m/z): [MH]+
calcd for C14H13NO2SCl: 294.0348; found: 294.0340.
N-(3-Chlorobenzoyl)-S-methyl-S-phenyl sulfoximine (3u).12c
Yield 73%; 107.3 mg; white solid; mp 106–108 ꢀC; Rf 0.27 (30%
ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.15
(s, 1H), 8.08–7.99 (m, 3H), 7.70 (t, J ¼ 7.6 Hz, 1H), 7.63 (t, J ¼ 7.6
Hz, 2H), 7.47 (d, J ¼ 8.0 Hz, 1H), 7.35 (t, J ¼ 8.0 Hz, 1H), 3.47 (s,
3H); 13C NMR (CDCl3, 100 MHz, ppm) d 173.0, 138.9, 137.6,
134.3, 134.1, 132.2, 129.9, 129.7, 129.5, 127.6, 127.3, 44.5; FTIR
(KBr) 3058, 3023, 2933, 1627, 1568, 1447, 1420, 1262, 978, 837,
746, 731, 684 cmꢂ1; HRMS (m/z): [MNa]+ calcd for C14H12NO2-
SClNa: 316.0169; found: 316.0163.
N-(4-Hydroxybenzoyl)-S-methyl-S-phenyl sulfoximine (3aa).
Yield 88%; 121.2 mg; white solid; mp 178–180 ꢀC; Rf 0.37 (50%
1
ethylacetate in hexanes); H NMR (DMSO-d6, 400 MHz, ppm)
N-(3-Bromobenzoyl)-S-methyl-S-phenyl sulfoximine (3v).12c
d 10.08 (s, 1H), 8.02 (d, J ¼ 7.6 Hz, 2H), 7.88 (d, J ¼ 8.4 Hz, 2H),
7.75 (t, J ¼ 7.6 Hz, 1H), 7.68 (t, J ¼ 7.6 Hz, 2H), 6.80 (d, J ¼ 8.8 Hz,
2H), 3.56 (s, 3H); 13C NMR (DMSO-d6, 100 MHz, ppm) d 172.3,
161.1, 139.1, 133.5, 131.1, 129.5, 127.0, 126.6, 114.7, 43.3; FTIR
(KBr) 3321, 3070, 3017, 2922, 1643, 1605, 1570, 1510, 1213, 1164,
1100, 975, 851, 742, 697 cmꢂ1; [MNa]+ calcd for C14H13NO3SNa:
298.0512; found: 298.0508.
N-(1-Naphthoyl)-S-methyl-S-phenyl sulfoximine (3ab).11a
Yield 90%; 139.2 mg; brown viscous liquid; Rf 0.23 (25% ethyl-
acetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 9.00 (d, J
¼ 8.8 Hz, 1H), 8.35 (dd, J ¼ 7.2 Hz, 1.2 Hz, 1H), 8.13–8.08 (m,
2H), 7.96 (d, J ¼ 8.4 Hz, 1H), 7.85 (dd, J ¼ 8.8 Hz, 1.6 Hz, 1H),
7.69 (tt, J ¼ 7.2 Hz, 1.2 Hz, 1H), 7.76–7.60 (m, 2H), 7.57–7.46 (m,
3H), 3.50 (s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 176.6,
139.2, 134.1, 133.9, 133.1, 132.5, 131.5, 129.94, 129.87, 128.4,
127.3, 126.6, 126.0, 124.6, 44.7; FTIR (KBr) 3056, 3020, 2928,
1628, 1590, 1509, 1447, 1345, 1280, 1218, 1146, 1097, 975, 849,
784, 738 cmꢂ1; HRMS (m/z): [MH]+ calcd for C18H16NO2S:
310.0901; found: 310.0915.
ꢀ
Yield 74%; 125.2 mg; white solid; mp 106–104 C [lit. 105–107
ꢀC];12c Rf 0.3 (30% ethylacetate in hexanes); 1H NMR (CDCl3, 400
MHz, ppm) d 8.31 (s, 1H), 8.12–7.99 (m, 3H), 7.70 (t, J ¼ 7.2 Hz,
1H), 7.67–7.58 (m, 3H), 7.29 (t, J ¼ 7.6 Hz, 1H), 3.47 (s, 3H); 13
C
NMR (CDCl3, 100 MHz, ppm) d 172.8, 138.8, 137.8, 135.1, 134.1,
132.6, 129.9, 129.8, 128.1, 127.3, 122.3, 44.7; FTIR (KBr) 3065,
3016, 2953, 1627, 1561, 1475, 1141, 982, 841, 749, 718, 688, 647
cmꢂ1
;
HRMS (m/z): [MNa]+ calcd for C14H12NO2SBrNa:
359.9665; found: 359.9658.
N-(2-Bromobenzoyl)-S-methyl-S-phenyl sulfoximine (3w).
ꢀ
Yield 82%; 138.7 mg; light brown solid; mp 89–91 C; Rf 0.28
(25% ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm)
d 8.11 (d, J ¼ 7.2 Hz, 2H), 7.80 (dd, J ¼ 7.6 Hz, 1.6 Hz, 2H), 7.70 (t,
J ¼ 7.2 Hz, 1H), 7.67–7.57 (m, 3H), 7.33 (td, J ¼ 7.6 Hz, 1.2 Hz,
1H), 7.22 (td, J ¼ 7.6 Hz, 1.6 Hz, 1H), 3.49 (s, 3H), 2.43 (s, 3H);
13C NMR (CDCl3, 100 MHz, ppm) d 175.2, 138.5, 134.2, 133.9,
131.3, 130.7, 129.9, 129.6, 127.5, 127.3, 120.5, 44.4; FTIR (KBr)
3063, 3016, 2955, 1633, 1587, 1447, 976, 744, 682 cmꢂ1; HRMS
(m/z): [MNa]+ calcd for C14H12NO2SBrNa: 359.9663; found:
359.9676.
N-(4-Methylbenzoyl)-S-methyl-S-(4-methylphenyl)
sulfox-
imine (3ae). Yield 95%; 136.5 mg; brown solid; mp 90–92 ꢀC; Rf
1
0.37 (30% ethylacetate in hexanes); H NMR (CDCl3, 500 MHz,
N-((2-Methylthio)benzoyl)-S-methyl-S-phenyl
sulfoximine
ppm) d 8.06 (d, J ¼ 8.0 Hz, 2H), 7.92 (d, J ¼ 8.5 Hz, 2H), 7.39 (d, J
¼ 8.0 Hz, 2H), 7.21 (d, J ¼ 8.0 Hz, 2H), 3.44 (s, 3H), 2.45 (s, 3H),
2.40 (s, 3H); 13C NMR (CDCl3, 125 MHz, ppm) d 174.4, 145.0,
142.8, 136.2, 133.1, 130.4, 129.6, 128.9, 127.3, 44.6, 21.7; FTIR
(KBr) 3063, 3026, 2926, 1626, 1610, 1569, 1449, 1312, 1281, 1220,
1137, 979, 845, 785, 756 cmꢂ1; HRMS (m/z): [MNa]+ calcd for
(3x). Yield 86%; 131.3 mg; yellow viscous liquid; Rf 0.2 (25%
ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.21
(dd, J ¼ 8.0 Hz, 1.2 Hz, 1H), 8.09 (d, J ¼ 7.2 Hz, 2H), 7.68 (t, J ¼
7.2 Hz, 1H), 7.61 (t, J ¼ 7.2 Hz, 2H), 7.47–7.39 (m, 1H), 7.25 (d, J
¼ 8.0 Hz, 1H), 7.14 (t, J ¼ 7.2 Hz, 1H), 3.49 (s, 3H), 2.43 (s, 3H);
13C NMR (CDCl3, 100 MHz, ppm) d 174.8, 142.3, 139.0, 133.9,
132.7, 131.9, 131.8, 129.8, 127.4, 124.3, 123.4, 44.6, 16.0; FTIR
(CH2Cl2) 3062, 3016, 2965, 1620, 1584, 1446, 1308, 1266, 1251,
1218, 978, 775, 744, 704 cmꢂ1; HRMS (m/z): [MNa]+ calcd for
C
16H17NO2SNa: 310.0881; found: 310.0886.
N-(4-Methylbenzoyl)-S-methyl-S-(4-methoxyphenyl) sulfox-
imine (3af). Yield 95%; 144.0 mg; white solid; mp 111–113 ꢀC; Rf
1
0.27 (40% ethylacetate in hexanes); H NMR (CDCl3, 500 MHz,
C
15H15NO2S2Na: 328.0411; found: 328.0404.
ppm) d 8.06 (d, J ¼ 8.0 Hz, 2H), 7.98 (d, J ¼ 9.0 Hz, 2H), 7.21 (d, J
¼ 8.0 Hz, 2H), 7.05 (d, J ¼ 9.0 Hz, 2H), 3.89 (s, 3H), 3.46 (s, 3H),
2.40 (s, 3H); 13C NMR (CDCl3, 125 MHz, ppm) d 174.4, 164.0,
142.7, 133.2, 130.3, 129.6, 129.5, 128.9, 115.0, 55.9, 44.9, 21.8;
FTIR (KBr) 3065, 3016, 2926, 1625, 1591, 1581, 1497, 1312, 1284,
N-(2-Nitrobenzoyl)-S-methyl-S-phenyl sulfoximine (3y). Yield
78%; 118.7 mg; yellow brown viscous liquid; Rf 0.6 (50% ethyl-
acetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.09–8.01
(m, 2H), 7.85–7.78 (m, 2H), 7.70 (tt, J ¼ 7.2 Hz, 1.2 Hz, 1H), 7.66–
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1173, 1136, 1098, 1021, 980, 834, 803 cmꢂ1; HRMS (m/z): [MNa]+ d 8.07 (d, J ¼ 8.0 Hz, 2H), 8.00 (d, J ¼ 7.5 Hz, 2H), 7.67 (t, J ¼ 7.5
calcd for C16H17NO3SNa: 326.0826; found: 326.0818.
Hz, 1H), 7.60 (t, J ¼ 7.5 Hz, 2H), 7.21 (d, J ¼ 8.0 Hz, 2H), 3.61 (q, J
N-(4-Methylbenzoyl)-S-methyl-S-(4-bromophenyl)
sulfox- ¼ 7.5 Hz, 2H), 2.40 (s, 3H), 1.30 (t, J ¼ 7.5 Hz, 3H); 13C NMR
ꢀ
imine (3ag). Yield 79%; 139.0 mg; white solid; mp 116–118 C; (CDCl3, 125 MHz, ppm) d 174.3, 142.8, 136.8, 133.8, 133.2,
Rf 0.43 (30% ethylacetate in hexanes); 1H NMR (CDCl3, 400 129.70, 129.66, 128.9, 128.2, 50.8, 21.8, 7.4; FTIR (KBr) 3063,
MHz, ppm) d 8.03 (d, J ¼ 8.4 Hz, 2H), 7.90 (d, J ¼ 8.8 Hz, 2H), 3027, 2925, 1626, 1610, 1571, 1447, 1283, 1282, 1209, 1173,
7.74 (d, J ¼ 8.8 Hz, 2H), 7.21 (d, J ¼ 8.0 Hz, 2H), 3.44 (s, 3H), 2.40 1135, 929, 840, 756, 706 cmꢂ1; HRMS (m/z): [MH]+ calcd for
(s, 3H); 13C NMR (CDCl3, 100 MHz, ppm) d 174.3, 143.1, 138.4,
C
16H18NO2S: 288.0110.; found: 288.0114.
133.1, 132.8, 129.7, 129.3, 128.94, 128.90, 44.5; FTIR (KBr) 3079,
N-(4-Methylbenzoyl)-S,S-tetramethylene sulfoximine (3am).
Yield 63%; 74.8 mg; yellow liquid; Rf 0.39 (50% ethylacetate in
3011, 2923, 1624, 1569, 1449, 1219, 979, 835, 820, 755, 529 cmꢂ1
;
HRMS (m/z): [MNa]+ calcd for C15H14NO2SBrNa: 373.9828; hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.02 (d, J ¼ 8.4 Hz,
found: 373.9832.
2H), 7.20 (d, J ¼ 8.0 Hz, 2H), 3.80–3.63 (m, 2H), 3.41–3.25 (m,
N-(4-Methylbenzoyl)-S-methyl-S-(4-chlorophenyl)
sulfox- 2H), 2.44–2.28 (m, 7H); 13C NMR (CDCl3, 100 MHz, ppm)
imine (3ah). Yield 84%; 129.3 mg; white solid; mp 122–124 ꢀC; d 175.2, 142.8, 132.7, 129.9, 128.9, 52.8, 23.9, 21.7; FTIR
Rf 0.3 (25% ethylacetate in hexanes); 1H NMR (CDCl3, 500 MHz, (CH2Cl2) 3033, 2957, 2849, 1630, 1612, 1563, 1453, 1313, 1293,
ppm) d 8.04 (d, J ¼ 8.0 Hz, 2H), 7.98 (d, J ¼ 8.5 Hz, 2H), 7.58 (d, J 1126, 1080, 921, 837 cmꢂ1; HRMS (m/z): [MH]+ calcd for
¼ 8.5 Hz, 2H), 7.21 (d, J ¼ 7.5 Hz, 2H), 3.44 (s, 3H), 2.40 (s, 3H);
13C NMR (CDCl3, 125 MHz, ppm) d 174.3, 143.1, 140.7, 137.8,
132.8, 130.2, 129.7, 129.0, 128.9, 44.6; FTIR (KBr) 3087, 3063,
2983, 1625, 1572, 1476, 1311, 1285, 1086, 981, 832, 791, 756, 719
C12H16NO2S: 238.0785.; found: 238.0794.
General procedure for transformation of N-(4-Methylbenzoyl)-
S-methyl-S-phenyl sulfoximine 3a to 4a
cmꢂ1
;
HRMS (m/z): [MNa]+ calcd for C15H14NO2SClNa:
N-(4-Methylbenzoyl)-S-methyl-S-phenyl sulfoximine 3a (354.5
mg, 1.3 mmol), and Lawesson's reagent (295 mg, 0.73 mmol)
was taken in an oven dried reaction tube equipped with
magnetic pellet. The reaction tube was evacuated and dry
toluene (4 mL) was added and reuxed for 8 hours and moni-
tored by TLC. Aer completion of the reaction, the reaction
mixture was then allowed to cool to room temperature and
solvent was evaporated and extracted with ethyl acetate (3 ꢃ 10
mL). Then the organic phase was dried over Na2SO4 and
concentrated in vacuum. The resulting reaction mixture was
puried by column chromatography on silica gel (hexanes: ethyl
acetate) to get product 4a.
353.1982; found: 353.1980.
N-(4-Methylbenzoyl)-S-methyl-S-(3-nitrophenyl) sulfoximine
(3ai). Yield 74%; 117.8 mg; light yellow solid; mp 123–125 ꢀC; Rf
1
0.27 (40% ethylacetate in hexanes); H NMR (CDCl3, 500 MHz,
ppm) d 8.56 (t, J ¼ 2.0 Hz, 1H), 8.52 (dd, J ¼ 8.0 Hz, 2.0 Hz, 2H),
8.38 (d, J ¼ 8.0 Hz, 1H), 8.01 (d, J ¼ 8.5 Hz, 2H), 7.84 (t, J ¼ 8.0
Hz, 1H), 7.22 (d, J ¼ 8.0 Hz, 1H), 3.49 (s, 3H), 2.41 (s, 3H); 13C
NMR (CDCl3, 125 MHz, ppm) d 174.4, 148.8, 143.5, 141.8, 133.0,
132.3, 131.3, 129.7, 129.1, 128.4, 122.8, 44.3, 21.8; FTIR (KBr)
3065, 3025, 2926, 1626, 1609, 1533, 1507, 1455, 1350, 1313, 983,
877, 838, 808, 757, 691 cmꢂ1; HRMS (m/z): [MNa]+ calcd for
C
15H14N2O4SNa: 341.0592; found: 341.0599.
N-(4-Methylthiobenzoyl)-S-methyl-S-phenyl sulfoximine (4a).
Yield 82%; 118.7 mg; yellow solid, mp 135–137 ꢀC; Rf 0.31 (20%
ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm) d 8.26
(d, J ¼ 8.0 Hz, 2H), 7.98 (d, J ¼ 8.4 Hz, 2H), 7.67 (t, J ¼ 7.2 Hz,
1H), 7.60 (t, J ¼ 7.2 Hz, 2H), 7.16 (d, J ¼ 8.0 Hz, 2H), 3.48 (s, 2H),
2.38 (s, 3H), 1.30 (t, J ¼ 7.5 Hz, 3H); 13C NMR (CDCl3, 100 MHz,
ppm) d 211.1, 142.9, 140.0, 137.8, 133.8, 129.9, 128.6, 128.5,
127.6, 44.9, 21.7; FTIR (KBr) 3176, 2953, 1647, 1609, 1574, 1435,
1136, 1022, 976, 834, 740, 685 cmꢂ1; HRMS (m/z): [MNa]+ calcd
for C15H15NO2S2Na: 312.0449; found: 312.0458.
N-(4-Methylbenzoyl)-S-methyl-S-(3-bromophenyl)
sulfox-
imine (3aj). Yield 73%; 128.6 mg; light brown solid; mp 106–108
1
ꢀC; Rf 0.37 (30% ethylacetate in hexanes); H NMR (CDCl3, 400
MHz, ppm) d 8.18 (t, J ¼ 1.6 Hz, 1H), 8.04 (d, J ¼ 8.0 Hz, 2H),
8.00–7.94 (m, 1H), 7.82–7.77 (m, 1H), 7.48 (t, J ¼ 8.0 Hz, 1H),
7.21 (d, J ¼ 8.0 Hz, 2H), 3.44 (s, 3H), 2.40 (s, 3H); 13C NMR
(CDCl3, 100 MHz, ppm) d 174.3, 143.1, 141.3, 137.0, 132.7,
131.3, 130.3, 129.7, 129.0, 125.9, 123.8, 44.6, 21.8; FTIR (KBr)
3025, 3016, 2922, 1626, 1610, 1568, 1436, 1312, 1282, 1223, 978,
842, 755, 693 cmꢂ1; HRMS (m/z): [MH]+ calcd for C15H15NO2SBr:
351.9998; found: 352.9992.
N-Benzoyl-S-methyl-S-(3-bromophenyl) sulfoximine (3ak).
Yield 77%; 130.2 mg; light brown solid; mp 104–106 ꢀC; Rf 0.36
(30% ethylacetate in hexanes); 1H NMR (CDCl3, 400 MHz, ppm)
d 8.21–8.12 (m, 3H), 7.98 (d, J ¼ 7.6 Hz, 1H), 7.84–7.77 (m, 1H),
7.56–7.46 (m, 2H), 7.42 (t, J ¼ 7.2 Hz, 2H), 3.46 (s, 3H), 2.40 (s,
3H); 13C NMR (CDCl3, 100 MHz, ppm) d 174.3, 141.2, 137.1,
135.4, 132.5, 131.3, 130.3, 129.6, 128.2, 125.9, 123.8, 44.5; FTIR
(KBr) 3069, 3029, 2922, 1623, 1608, 1566, 1445, 978, 835, 755,
Acknowledgements
We thank DST nano mission (SR/NM/NS-1034/2012(G)) for
nancial support. NS thanks CSIR, New Delhi, India for senior
research fellowship.
Notes and references
710 cmꢂ1
;
HRMS (m/z): [MH]+ calcd for C14H13NO2SBr:
1 (a) W. Dong, K. Parthasarathy, Y. Cheng, F. Pan and C. Bolm,
Chem.–Eur. J., 2014, 20, 15732; (b) D.-G. Yu, F. de Azambuja
and F. Glorius, Angew. Chem., Int. Ed., 2014, 53, 2754; (c)
W. Dong, L. Wang, K. Parthasarathy, F. Pan and C. Bolm,
Angew. Chem., Int. Ed., 2013, 52, 11573; (d) M. Harmata,
337.9830; found: 337.9826.
N-(4-Methylbenzoyl)-S-ethyl-S-phenyl sulfoximine (3al).
Yield 91%; 130.8 mg; light yellow solid, mp 127–129 ꢀC; Rf 0.27
(25% ethylacetate in hexanes); 1H NMR (CDCl3, 500 MHz, ppm)
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conditions, 88%, 92% and 93% yield of 3a was isolated.
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RSC Adv., 2016, 6, 37226–37235 | 37235