Potassium fluoride as an efficient and reusable reagent for the synthesis of N,N-dialkylsulfonamides via Aza-conjugate addition reaction under microwave irradiation

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Potassium Fluoride as an Efficient and
Reusable Reagent for the Synthesis
of N,N-Dialkylsulfonamides via Aza-
Conjugate Addition Reaction Under
Microwave Irradiation
Alireza Hasaninejad a , Abdolkarim Zare b , Abolfath Parhami b
, Ahmad Reza Moosavi-Zare b , Raheleh Bargebid c , Mohammad
Hassan Beyzavi c , Ali Khalafi-Nezhad c , Azam Arghoon b , Maria
Merajoddin b , Sayyed Ali Moosavi b , Abdoreza Dara b & Mohsen
Shekouhy a
a Department of Chemistry, Faculty of Sciences , Persian Gulf
University , Bushehr, Iran
b Department of Chemistry , Payame Noor University (PNU) ,
Bushehr, Iran
c Department of Chemistry, College of Sciences , Shiraz University ,
Shiraz, Iran
Published online: 10 Jul 2009.
To cite this article: Alireza Hasaninejad , Abdolkarim Zare , Abolfath Parhami , Ahmad Reza Moosavi-
Zare , Raheleh Bargebid , Mohammad Hassan Beyzavi , Ali Khalafi-Nezhad , Azam Arghoon , Maria
Merajoddin , Sayyed Ali Moosavi , Abdoreza Dara & Mohsen Shekouhy (2009) Potassium Fluoride as
an Efficient and Reusable Reagent for the Synthesis of N,N-Dialkylsulfonamides via Aza-Conjugate
Addition Reaction Under Microwave Irradiation, Organic Preparations and Procedures International:
The New Journal for Organic Synthesis, 41:4, 291-299, DOI: 10.1080/00304940903077949
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Organic Preparations and Procedures International, 41:291–299, 2009
Copyright © Taylor & Francis Group, LLC
ISSN: 0030-4948 print
DOI: 10.1080/00304940903077949
Potassium Fluoride as an Efficient and Reusable
Reagent for the Synthesis of
N,N-Dialkylsulfonamides via Aza-Conjugate
Addition Reaction Under Microwave Irradiation
Alireza Hasaninejad,1 Abdolkarim Zare,2 Abolfath Parhami,2
Ahmad Reza Moosavi-Zare,2 Raheleh Bargebid,3
Mohammad Hassan Beyzavi,3 Ali Khalafi-Nezhad,3
Azam Arghoon,2 Maria Merajoddin,2 Sayyed Ali Moosavi,2
Abdoreza Dara,2 and Mohsen Shekouhy1
1Department of Chemistry, Faculty of Sciences, Persian Gulf University
Bushehr, Iran
2Department of Chemistry, Payame Noor University (PNU) Bushehr, Iran
3Department of Chemistry, College of Sciences, Shiraz University Shiraz, Iran
N,N-Dialkyl derivatives of sulfonamides are significant due to their potential applications
as anti-ulcer, antidepressant, anti-emetic analgesic, psychostimulant and anti-inflammatory
agents.1 Aza-conjugate addition of sulfonamides to electrophilic double bonds can be a use-
ful synthetic route toward N,N-dialkylsulfonamides. Indeed, to the best of our knowledge,
this transformation has scarcely been studied in the literature. Reagents such as Al2O3,2
ZnO,3 MgO,4 K2CO3 and PBu3 have been applied to achieve aza-conjugate addition
reaction of sulfonamides. However, most of these reagents are useful for the synthesis
of N-alkylsulfonamides but not of N,N-dialkylated adducts.2–5 Therefore, it seems highly
desirable to develop an efficient reagent for the preparation of N,N-dialkylsulfonamides.
Solvent-free organic reactions have become as a useful protocol in organic synthesis.7,8 The
utilization of microwave irradiation coupled with solvent-free reaction conditions, provides
chemical processes with special attributes, such as enhanced reaction rates, higher yields,
easier work-up, better selectivity, and improved ease of manipulation.7,8 KF immobilized
onto supports possessing high-surface area or accompanied with other reagents has been
extensively used in organic synthesis;9–19 however, there are only a few reports on the
applications of KF itself as reagent in the literature.20,21 In extension of our previous studies
5
6
Received August 22, 2008; in final form April 24, 2009.
Address correspondence to either Alireza Hasaninejad, Department of Chemistry, Faculty of
Sciences, Persian Gulf University, Bushehr 75169, Iran. E-mail: ahassaninejad@yahoo.com; or Ab-
dolkarim Zare, Department of Chemistry, Payame Noor University (PNU), Bushehr 1698, Iran.
E-mail: abdolkarimzare@yahoo.com
291

292
Zare et al.
on the synthesis of sulfonamide derivatives3–5 as well as green organic synthesis,3–5,22–27
herein we report an efficient method for the preparation of N,N-dialkylsulfonamides via
aza-conjugate addition of sulfonamides to α,β-unsaturated esters in the presence of KF
and tetrabutylammonium bromide (TBAB) under microwave irradiation in the absence of
solvent (Scheme 1).
KF (25 mol%), TBAB
PhSO2NH2
+
PhSO2N(CH2CH2CO2Bu)2
98%
MW, 300 W, 130 °C
14 min
CO2Bu
Scheme 1
The aza-conjugate addition of benzenesulfonamide (2 mmol) to n-butyl acrylate
(4.4 mmol) in the presence of different molar ratios of KF and TBAB (1 mmol) at range
of 100–500 W of microwave power (max. 130◦C) (Scheme 1) was studied in order to
determine the optimal conditions with respect to molar ratio of the reagent to the substrate
and microwave power. The data summarized in Table 1 indicates that reasonable results
were obtained when the reaction was carried out using 25 mol% KF at 300 W of microwave
power. Under these conditions, only N,N-dialkylsulfonamide was produced in 98% yield,
and no mono-N-alkylated product was formed. The reaction was also examined in the
absence of KF; however, these conditions were not efficient (Table 1). In fact, this reaction
requires a base to abstract a proton from the amino group of the sulfonamide thus generating
the nucleophile to attack the β-carbon of the α,β-unsaturated compound.16,21,28–30 In this
study, it was found that potassium fluoride can efficiently serve as the base.16,21,28–30
To assess the efficiency of microwave heating in comparison with conventional heating,
the reaction of benzenesulfonamide (2 mmol) with n-butyl acrylate (4.4 mmol) in the
presence of KF (25 mol%) and TBAB (1 mmol) was examined in an oil-bath (130◦C). Under
these conditions, the selectivity decreased and the N,N-dialkyl and N-alkyl sulfonamides
were obtained in 87 and 6% respectively after 3 hrs. Thus, microwave irradiation has an
Table 1
Influence of Ratios of KF to the Substrate and Microwave Power in the Presence of TBAB
Yield (%)
Molar Ratio of
KF (mol%)
MW Power
(W)
Time
(min)
N,N-Dialkylated
Product
N-Alkylated
Product
0
15
25
35
25
25
25
25
300
300
300
300
100
200
400
500
30
20
14
11
25
20
9
7
84
98
98
47
73
96
90
29
10
—
—
23
15
—
—
5

Synthesis of N,N-Dialkylsulfonamides via Aza-Conjugate Addition
293
Table 2
Comparative Reaction between Benzenesulfonamide and n-Butyl Acrylate using KF in
Various Solvents versus the Solvent-Free Method under Microwave Irradiation
Yield (%)
Entry
Solvent
DMSO
DMF
HMPTA
Solvent-free
Solvent-free
Solvent-free
Time (min)
N,N-Dialkyl Product
N-Alkyl Product
1
2
3
4a
5b
6c
18
18
20
14
25
14
82
94
79
98
19
73
9
4
7
—
12
Trace
aSolvent-free conditions in the presence of TBAB.
bSolvent-free conditions without TBAB.
cSolvent-free conditions using TBAF.
essential influence on the progress and the selectivity of the aza-conjugate addition reaction.
In another study, the effectiveness of the solvent-free method versus solution conditions
was investigated (Table 2). For this purpose, a mixture of benzenesulfonamide (2 mmol),
n-butyl acrylate (4.4 mmol), KF (25 mol%) and TBAB (1 mmol) was irradiated in a
microwave oven (300 W, max. 130◦C) in various solvents (4 mL). Higher yield of the N,N-
dialkylated product in shorter reaction times were obtained in the solvent-free conditions.
The reaction was also examined in the absence of TBAB under solventless conditions;
however, these conditions were not efficient (see Table 2, Entry 5). Thus, the presence of
TBAB in the reaction is necessary. In general, TBAB melts at 100◦C and solubilizes the
reactants.5,25,31 Moreover, this quaternary ammonium salt absorbs the microwave irradiation
and increases the reaction temperature.5,25 Moreover, the reaction of benzenesulfonamide
with n-butyl acrylate was checked using tetrabutylammonium fluoride (TBAF) without KF
under solvent-free conditions at 300 W (max. 130◦C). Under these conditions, the product
was obtained in 73% after 14 min (Table 2, Entry 6).
To evaluate the efficiency and potency of our method with respect to the reported
methods for the synthesis of N,N-dialkylsulfonamides via aza-conjugate addition reaction,
we have tabulated the results of the reported methods for the synthesis of N,N-di(3-carbo-
n-butoxyethyl)benzenesulfonamide in Table 3. Clearly, in comparison with the reported
methods, our method significantly improved the synthesis of N,N-dialkylated sulfonamides
via aza-conjugate addition reaction.
To determine the generality and scope of the method, the reaction was examined
with different sulfonamides and α,β-unsaturated esters (Table 4). The reactions proceeded
efficiently and the desired conjugate adducts were obtained in good to excellent yields
in short reaction times. The nature of the alkoxy group of α,β-unsaturated esters had
a negligible effect on the reaction results (Entries 1–8). With sterically hindered ethyl
methacrylate, lower yields were obtained even under prolonged reaction times (Entries 9
and 10) while with ethyl crotonate, only the N-monoalkyl product was isolated in 92%

294
Zare et al.
Table 3
Synthesis of N,N-di(3-carbo-n-butoxyethyl)benzenesulfonamide using
the reported methods compared to Present Method
Entry
Reagent
Time (min)
Yield (%)
Ref.
1
2
3
4
5a
KF
ZnO
MgO
K2CO3
PBu3
14
5
5
5
1080
98
9
7
16
52
Present Work
3
4
5
6
aYield of N,N-dialkylsulfonamide from p-toluenesulfonamide and ethyl
acrylate.
Table 4
Synthesis of N,N-Dialkylsulfonamides under Solvent-free and Microwave Irradiation
Entry
R
R1 R2
X
Time (min) Yield (%)
m.p. (lit.)
Oil (Oil)3
1a
2
3
4
5
6
7
8
C6H5
C6H5
C6H5
C6H5
C6H5
C6H5
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
CO2CH2CH3
27
14
14
15
17
18
17
18
20
20
30
96
98
97
97
97
95
97
95
79
77
—
CO2CH2(CH2)2CH3
CO2CH2(CH2)4CH3
CO2CH2C6H5
CO2CH2CH2C6H5
CO2CH2CH = CHC6H5
CO2CH2(CH2)2CH3
CO2CH2C6H5
Oil (Oil)3
Oil (Oil)3
Oil (Oil)4
Oil (Oil)4
Oil (Oil)4
Oil (Oil)5
Oil
p-CH3C6H4
p-CH3C6H4
C6H5
p-CH3C6H4
C6H5
9b
10b
11c
H
H
CH3 CO2CH2CH3
CH3 CO2CH2CH3
Oil (Oil)5
Oil
—
CH3
H
CO2CH2CH3
12
13
14d
15d
16d
17e
H
H
H
H
H
H
H
H
H
H
H
H
CO2CH2(CH2)2CH3
CO2CH2CH2C6H5
CN
COCH3
CHO
14
20
30
30
30
30
97
64
39
Trace
—
—
Oil
Oil
CH3
p-CH3C6H4
C6H5
C6H5
C6H5
97–99 (102–104)6
—
—
—
CONH2
aBecause of lower boiling point of ethyl acrylate, this reaction was performed at 100◦C (300 W of
microwave power); moreover, in this case, ethyl acrylate/benzenesulfonamide ratio (mol/mol) was
2.5/1.
bThis reaction was carried out at 400 W (max. 140◦C), and in this case, 100 mol% of KF and
TBAB were used.
cIn this reaction, only mono-N-alkyl product was produced in 92%.
dThis reaction was carried out in a capped vessel at 100◦C, and α,β-unsaturated com-
pound/benzenesulfonamide ratio (mol/mol) was 3/1.
eThis reaction was examined at 120◦C.

Synthesis of N,N-Dialkylsulfonamides via Aza-Conjugate Addition
295
yield after 30 min (Entry 11). p-Toluenesulfonamide and 2-naphthylsulfonamide afforded
the expected products in excellent yields (Entries 7, 8, 10 and 12). Moreover, the method
was successful for N,N-dialkylation of alkysulfonamides (Entry 13). The method was
also examined for the reaction of sulfonamides with α,β-unsaturated nitriles, ketones,
aldehydes and amides. As Table 4 indicates, while acrylonitrile gave the corresponding N,N-
dialkylsulfonamide in moderate yield (Entry 14), the reaction was not successful with other
α,β-unsaturated compounds (Entries 15–17). One of the most interesting properties of KF
is its ease of recycling. The yields of N,N-di(3-carbo-n-butoxyethyl)benzenesulfonamide
(model compound) in the 2nd and 3rd and 4th uses of the reagent were nearly as high as in
the first use.
In summary, we have developed a new method for the synthesis of N,N-
dialkylsulfonamides via aza-conjugate addition of sulfonamides to α,β-unsaturated es-
ters promoted by microwave irradiation. The advantages of this method are generality,
high yield, high selectivity, short reaction time, low cost, ease of product isolation, and
agreement with the green chemistry protocols.
Experimental Section
All chemicals were purchased from Merck or Fluka Chemical Companies. All known
compounds were identified by comparison of their spectral data with those in the authen-
tic samples. All reactions were carried out using laboratory microwave oven (MW 3000,
Landgraf Company, Germany). IR spectra were run on a Shimadzu FTIR-8300 spectropho-
tometer. The 1H NMR (250 MHz) and 13C NMR (62.5 mhz) were run on a Bruker Avance
DPX-250, FT-NMR spectrometer. Microanalysis was performed on a Perkin-Elmer 240-B
microanalyzer. Mass spectra were recorded on a Shimadzu GC MS-QP 1000 EX apparatus.
General Procedure for the Synthesis of N,N-Dialkylsulfonamides
To a well-ground mixture of the sulfonamide (2 mmol), KF (0.029 g, 0.5 mmol) and TBAB
(0.322 g, 1 mmol) in a microwave vessel was added the α,β-unsaturated ester (4.4 mmol)
and mixed thoroughly with a glass rod (the microwave vessel was open). The resulting
mixture was irradiated in a microwave oven at 300 W at a maximum internal temperature
of 130◦C (the internal reaction temperature was measured by a sensor that was inserted
in the reaction mixture). After each 4 min, the microwave irradiation was stopped and
the reaction mixture was rapidly mixed with a glass rod. After completion of the reaction
monitored with TLC, the reaction mixture was cooled to room temperature and suspended
in EtOAc (40 mL), filtered to separate the reagent and the filtrate was washed with water
(2 × 60 mL) and dried with MgSO4. The solvent was evaporated and the crude product was
purified by short column chromatography on silica gel eluted with EtOAc/n-hexane (1/3).
After isolation of the products, the remaining KF was washed with EtOAc, dried and used
for the next run under identical reaction conditions.
N,N-Di(3-carbethoxyethyl)benzenesulfonamide (Table 4, Entry 1): Colorless oil,
1
(lit.3 oil); IR (neat): 3028, 2984, 1733, 1447, 1317 cm−1; H NMR (CDCl3): δ 1.22 (t,
J = 7.1 Hz, 6H, 2CH3), 2.59 (t, J = 5.0 Hz, 4H, 2O=CCH2), 3.45 (t, J = 5.0 Hz, 4H,
2O=CCH2CH2), 4.08 (q, J = 7.1 Hz, 4H, 2OCH2), 7.46–7.57 (complex, 3H, H3-H5 of the

296
Zare et al.
aromatic ring), 7.87 (m, 2H, H2 and H6 of the aromatic ring); 13C NMR (CDCl3): δ 13.9,
32.8, 44.7, 60.4, 127.2, 129.1, 132.6, 138.9, 170.9; MS (m/z): 357 (M+).
N,N-Di(3-carbo-n-butoxyethyl)benzenesulfonamide (Table 4, Entry 2): Colorless
1
oil, (lit.3 oil); IR (neat): 3036, 2966, 1732, 1447, 1317 cm−1; H NMR (CDCl3): δ 0.92
(t, J = 6.5 Hz, 6H, 2CH3), 1.33 (m, 4H, 2CH3CH2),1.56 (m, 4H, 2CH3CH2CH2), 2.63 (t,
J = 5.1 Hz, 4H, 2O=CCH2), 3.45 (t, J = 5.1 Hz, 4H, 2O=CCH2CH2), 4.06 (t, J = 6.9 Hz,
4H, 2OCH2), 7.51–7.60 (complex, 3H, H3-H5 of the aromatic ring), 7.82 (m, 2H, H2 and
H6 of the aromatic ring); 13C NMR (CDCl3): δ 13.5, 18.9, 30.5, 34.2, 44.4, 64.2, 126.9,
129.0, 132.4, 138.9, 171.1; MS (m/z): 413 (M+).
N,N-Di(3-carbo-n-hexyloxyethyl)benzenesulfonamide (Table 4, Entry 3): Colorless
1
oil, (lit.3 oil); IR (neat): 3031, 2974, 1733, 1447, 1316 cm−1; H NMR (CDCl3): δ 0.89
(t, J = 6.6 Hz, 6H, 2CH3), 1.26–1.32 (complex, 12H, 2CH3CH2, 2CH3CH2CH2 and
2CH3(CH2)2CH2), 1.58 (m, 4H, 2CH3(CH2)3CH2), 2.61 (t, J = 5.0 Hz, 4H, 2O=CCH2),
3.41 (t, J = 5.0 Hz, 4H, 2O=CCH2CH2), 4.05 (t, J = 6.9 Hz, 4H, 2OCH2), 7.43–7.50
(complex, 3H, H3-H5 of the aromatic ring), 7.74 (m, 2H, H2 and H6 of the aromatic ring);
13C NMR (CDCl3): δ 13.8, 22.3, 25.5, 28.0, 30.4, 33.9, 44.5, 64.4, 126.4, 128.9, 132.1,
139.4, 171.4; MS (m/z): 392 (M+-C6H5), 368 (M+-C6H13O), 328 (M+-C6H5SO2).
N,N-Di(3-carbobenzyloxyethyl)benzenesulfonamide (Table 4, Entry 4): Pale yellow
oil, (lit.4 oil); IR (neat): 3051, 2965, 1734, 1447, 1316 cm−1; 1H NMR (CDCl3): δ 2.58 (t,
J = 5.0 Hz, 4H, 2O=CCH2), 3.36 (t, J = 5.0 Hz, 4H, 2O=CCH2CH2), 5.00 (s, 4H,
2OCH2), 7.22–7.25 (complex, 10H, 2C6H5CH2), 7.39–7.48 (complex, 3H, H3-H5 of the
aromatic ring of sulfonamide moiety), 7.72 (m, 2H, H2 and H6 of the aromatic ring of
sulfonamide moiety); 13C NMR (CDCl3): δ 33.3, 43.9, 65.5, 126.2, 127.7, 128.1, 128.9,
129.5, 131.8, 134.4, 137.8, 171.4; MS (m/z): 404 (M+-C6H5), 340 (M+-C6H5SO2).
N,N-Di(3-carbophenethyloxyethyl)benzenesulfonamide (Table 4, Entry 5): Pale
1
yellow oil, (lit.4 oil); IR (neat): 3045, 2942, 1733, 1447, 1331 cm−1; H NMR (CDCl3):
δ 2.51 (t, J = 5.2 Hz, 4H, 2O=CCH2), 2.82 (t, J = 6.9 Hz, 4H, 2ArCH2), 3.30 (t, J =
5.2 Hz, 4H, 2O=CCH2CH2), 4.19 (t, J = 6.9 Hz, 4H, 2OCH2), 7.10–7.19 (complex, 10H,
2C6H5CH2), 7.42–7.45 (complex, 3H, H3-H5 of the aromatic ring of sulfonamide moiety),
7.78 (m, 2H, H2 and H6 of the aromatic ring of sulfonamide moiety); 13C NMR (CDCl3):
δ 34.3, 34.9, 44.9, 65.2, 126.6, 126.7, 126.9, 128.6, 128.8, 129.2, 132.8, 137.5, 171.0; MS
(m/z): 432 (M+-C6H5), 388 (M+-C8H9O), 368 (M+-C6H5SO2).
N,N-Di(3-carbocinnamyloxyethyl)benzenesulfonamide (Table 4, Entry6): Paleyel-
low oil, (lit.4 oil); IR (neat): 3026, 2981, 1732, 1448, 1317 cm−1; 1H NMR (CDCl3): δ 2.51
(t, J = 5.1 Hz, 4H, 2O=CCH2), 3.41 (t, J = 5.1 Hz, 4H, 2O=CCH2CH2), 4.73 (m,
4H, 2OCH2), 6.15 (m, 2H, 2PhCH = CH), 6.54 (d, 2H J = 15.7 Hz, PhCH), 7.28–7.36
(complex, 10H, 2C6H5CH2), 7.41–7.47 (complex, 3H, H3-H5 of the aromatic ring of sul-
fonamide moiety), 7.94 (m, 2H, H2 and H6 of the aromatic ring of sulfonamide moiety);
13C NMR (CDCl3): δ 33.8, 43.2, 65.4, 122.4, 123.0, 126.7, 126.9, 127.9, 128.5, 129.4,
132.4, 134.1, 139.3, 171.5; MS (m/z): 392 (M+-C6H5SO2).
N,N-Di(3-carbo-n-butoxyethyl)-p-toluenesulfonamide (Table 4, Entry 7): Pale yel-
low oil, (lit.5 oil); IR (neat): 3056, 2975, 1734, 1317 cm−1; 1H NMR (CDCl3): δ 0.92 (t, J =
6.9 Hz, 6H, 2CH2CH3), 1.32 (m, 4H, 2CH3CH2),1.57 (m, 4H, 2CH3CH2CH2), 2.42 (s, 3H,
ArCH3), 2.63 (t, J = 5.2 Hz, 4H, 2O=CCH2), 3.43 (t, J = 5.2 Hz, 4H, 2O=CCH2CH2),
4.02 (t, J = 7.0 Hz, 4H, 2OCH2), 7.31 (d, J = 7.9 Hz, 2H, H3 and H5 of the aromatic

Synthesis of N,N-Dialkylsulfonamides via Aza-Conjugate Addition
297
ring), 7.72 (d, J = 7.9 Hz, 2H, H2 and H6 of the aromatic ring); 13C NMR (CDCl3):
δ 13.6, 19.0, 21.4, 30.4, 33.9, 45.0, 64.5, 126.9, 129.5, 135.9, 143.5, 172.5; MS (m/z):
427 (M+).
N,N-Di(3-carbbenzyloxyethyl)-p-toluenesulfonamide (Table 4, Entry 8): Pale yel-
low oil; IR (neat): 3056, 2971, 1734, 1316 cm−1; 1H NMR (CDCl3): δ 2.38 (s, 3H, ArCH3),
2.60 (t, J = 5.2 Hz, 4H, 2O=CCH2), 3.39 (t, J = 5.2 Hz, 4H, 2O=CCH2CH2), 5.04 (s,
4H, 2OCH2), 7.18–7.22 (complex, 10H, 2C6H5CH2), 7.34 (d, J = 7.9 Hz, 2H, H3 and H5
of the aromatic ring of sulfonamide moiety), 7.74 (d, J = 7.9 Hz, 2H, H2 and H6 of the
aromatic ring of sulfonamide moiety); 13C NMR (CDCl3): δ 22.2, 33.7, 44.5, 65.8, 126.3,
127.1, 128.3, 129.0, 129.9, 134.9, 135.6, 143.1, 171.9; MS (m/z): 340 (M+-C7H7SO2).
Anal. for C27H29NO6S: C, 65.44; H, 5.90; N, 2.83. Found: C, 65.63; H, 6.04; N, 2.71.
N,N-Di(3-carbethoxy-2-methyethyl)benzenesulfonamide (Table 4, Entry 9): Pale
yellow oil, (lit.5 oil); IR (neat): 3042, 2982, 1732, 1447, 1316 cm−1; 1H NMR (CDCl3):
δ 1.09–1.19 (complex, 12H, 4CH3), 2.78 (m, 2H, 2O=CCH), 3.22–3.27 (complex, 4H,
2O=CCH2CH2), 4.03 (q, J = 7.0 Hz, 4H, 2OCH2), 7.44–7.53 (complex, 3H, H3-H5 of the
aromatic ring), 7.75 (m, 2H, H2 and H6 of the aromatic ring); 13C NMR (CDCl3): δ 14.1,
15.3, 39.2, 52.4, 60.7, 127.3, 129.1, 132.7, 139.0, 174.7; MS (m/z): 385 (M+).
N,N-Di(3-carbethoxy-2-methyethyl)-p-toluenesulfonamide (Table 4, Entry 10):
1
Pale yellow oil; IR (neat): 3057, 2973, 1733, 1447, 1316 cm−1; H NMR (CDCl3): δ
1.12–1.24 (complex, 12H, 4CH3), 2.44 (s, 3H, ArCH3), 2.73 (m, 2H, 2O=CCH), 3.25–3.31
(complex, 4H, 2O=CCH2CH2), 4.10 (q, J = 7.0 Hz, 4H, 2OCH2), 7.33 (d, J = 7.8 Hz,
2H, H3 and H5 of the aromatic ring), 7.76 (d, J = 7.8 Hz, 2H, H2 and H6 of the aromatic
ring); 13C NMR (CDCl3): δ 13.9, 15.0, 22.7, 39.4, 51.2, 61.2, 126.6, 129.7, 136.1, 142.95,
172.1; MS (m/z): 399 (M+).
Anal. for C19H29NO6S: C, 57.12; H, 7.32; N, 3.51. Found: C, 56.87; H, 7.21; N, 3.65.
N,N-Di(3-carbo-n-butoxyethyl)-2-naphthylsulfonamide (Table 4, Entry 12): Pale
1
yellow oil; IR (neat): 3046, 2981, 1732, 1448, 1327 cm−1; H NMR (CDCl3): δ 0.90 (t,
J = 6.6 Hz, 6H, 2CH3), 1.36 (m, 4H, 2CH3CH2), 1.57 (m, 4H, 2CH3CH2CH2), 2.52 (t,
4H, J = 5.1 Hz, 2O=CCH2), 3.43 (t, 4H, J = 5.1 Hz, 2O=CCH2CH2), 4.06 (t, 4H, J =
7.0 Hz, 2OCH2), 7.49–7.55 (complex, 4H), 7.76–7.78 (complex, 3H); 13C NMR (CDCl3):
δ 13.7, 19.1, 30.2, 33.6, 44.8, 64.8, 122.1, 128.0, 127.7, 128.0, 128.2, 128.5, 128.9, 129.1,
129.6, 132.3, 171.8; MS (m/z): 390 (M+-C4H9O), 272 (M+-C10H7SO2).
Anal. for C24H33NO6S: C, 62.18; H, 7.17; N, 3.02. Found: C, 62.01; H, 7.05; N, 3.18.
N,N-Di(3-carbophenethyloxyethyl)methanesulfonamide (Table 4, Entry 13): Pale
yellow oil; IR (neat): 3061, 2973, 1732, 1446, 1329, 1161 cm−1; 1H NMR (CDCl3): δ 1.67
(s, 3H, CH3), 2.80–2.89 (m, 8H), 3.81–3.88 (m, 8H), 7.21-.7.32 (complex, 10H, 2C6H5);
13C NMR (CDCl3): δ 35.0, 35.2, 39.2, 63.7, 64.9, 126.6, 128.6, 129.0, 138.5, 170.6; MS
(m/z): 368 (M+-CH3SO2).
Anal. for C23H29NO6S: C, 61.72; H, 6.53; N, 3.13. Found: C, 62.01; H, 6.72; N, 2.97.
N,N-Di(2-cyanoethyl)-p-toluenesulfonamide (Table 4, Entry 14): Pale yellow solid;
mp. 97–99◦C (lit.6 102–104◦C); IR (KBr): 2947, 2253, 1599, 1337, 1159 cm−1; 1H NMR
(CDCl3): δ 2.43 (s, 3H, ArCH3), 2.69 (t, J = 6.9 Hz, 4H, 2NCCH2), 3.47 (t, J = 6.9 Hz,
4H, 2NCH2), 7.30 (d, J = 7.9 Hz, 2H, H3 and H5 of the aromatic ring), 7.72 (d, J = 7.9 Hz,
2H, H2 and H6 of the aromatic ring); 13C NMR (CDCl3): δ 18.9, 22.1, 45.6, 117.6, 127.2,
129.8, 135.3, 144.4; MS (m/z): 277 (M+).

298
Zare et al.
Acknowledgements
We appreciate Persian Gulf University and Payame Noor University Research Councils for
the financial support of this work.
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