Sulfonamidation of halogen-substituted electrophiles with N-(2,2,2-trichloroethyl)arenesulfonamides

Article abstract of DOI:10.1134/S1070428017060021

Reactions of N-(2,2,2-trichloroethyl)arenesulfonamides with primary alkyl bromides and iodides, allyl bromide, chloroacetonitrile, and benzyl chloride in acetonitrile on heating in the presence of potassium carbonate gave the corresponding N-alkyl-N-(2,2,2-trichloroethyl)arenesulfonamides.

Full text of DOI:10.1134/S1070428017060021

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2017, Vol. 53, No. 6, pp. 824–827. © Pleiades Publishing, Ltd., 2017.
Original Russian Text © G.N. Chernysheva, I.V. Nikitin, I.B. Rozentsveig, 2017, published in Zhurnal Organicheskoi Khimii, 2017, Vol. 53, No. 6,
pp. 810–813.
Sulfonamidation of Halogen-Substituted Electrophiles
with N-(2,2,2-Trichloroethyl)arenesulfonamides
G. N. Chernysheva,* I. V. Nikitin, and I. B. Rozentsveig
Favorskii Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences,
ul. Favorskogo 1, Irkutsk, 664033 Russia
*e-mail: gelya2010@irioch.irk.ru
Received July 29, 2016
Abstract—Reactions of N-(2,2,2-trichloroethyl)arenesulfonamides with primary alkyl bromides and iodides,
allyl bromide, chloroacetonitrile, and benzyl chloride in acetonitrile on heating in the presence of potassium
carbonate gave the corresponding N-alkyl-N-(2,2,2-trichloroethyl)arenesulfonamides.
DOI: 10.1134/S1070428017060021
N-(Polychloroethyl) sulfonamides are promising
subjects of fundamental stereochemical studies [1–3];
they also attract interest as key reagents in the syn-
thesis of difficultly accessible sulfonamide derivatives,
including amino acids [4, 5], amidine derivatives of
amino acids [6], aminocarbonyl compounds [7], and
various heterocycles such as aziridines [8, 9], benzo-
furans [10], and fused imidazoles [11–13].
N,N,4-trichlorobenzenesulfonamide with 1,1-dichloro-
ethene was reported for the first time in [18]; however,
the yield of 4 was not given. We succeeded in ob-
taining N-(2,2,2-trichloroethyl)arenesulfonamides 2–4
in up to 92% yield via a one-pot reaction. Heating of
the reactants for 6 h in chlorobenzene and the subse-
quent reduction of intermediate N-chloro amides with-
out their isolation in the pure state favored increased
yield of the target products (Scheme 1). Addition of
radical initiators (AIBN or benzoyl peroxide) in the
first stage considerably accelerated the process, but the
yield of 2–4 decreased due to side reactions.
With the goal of developing methods for the
synthesis of new N-(polychloroethyl)sulfonamides as
substrates for further transformations and potential bio-
logically active compounds, in the present work we
studied reactions of some N-(2,2,2-trichloroethyl)-
arenesulfonamides with halogen-containing electro-
philes. Reactions involving the NH group of N-(poly-
chloroethyl)sulfonamides have been poorly studied;
a few known examples include intramolecular hetero-
cyclizations [8, 9, 14, 15] and reactions with methyl
vinyl ketone [16] and propyl, allyl, and propargyl
bromides [17].
The structure of 2–4 was unambiguously proved by
spectral and analytical data. The IR spectra of 2–4
characteristically displayed absorption bands due to
stretching vibrations of NH (3300 cm–1) and SO2
1
groups (1160, 1370 cm–1). In the H NMR spectra of
2–4 we observed signals of aromatic protons, a doublet
at δ ~4 ppm due to methylene protons, and a downfield
triplet at ~9.0 ppm due to NH proton with the intensity
ratio corresponding to the assigned structure.
In this work we have optimized conditions of the
reaction of N,N-dichloroarenesulfonamides 1a–1c with
1,1-dichloroethene, leading to N-(2,2,2-trichloroethyl)-
arenesulfonamides 2–4 (Scheme 1). The reaction of
Compounds 2–4 were brought into reactions with
halogen-containing electrophiles; as a result, N-alkyl
derivatives 5–7 were isolated (Scheme 2). The best
Scheme 1.
Cl
Cl
H
N
Cl
CH2
Cl
PhCl, ∆
NaHSO3
ArSO2NCl2
+
N
Cl
Cl
Cl
Cl
ArSO2
ArSO2
Cl
1a–1c
2–4
1a, 2, Ar = Ph; 1b, 3, R = 4-MeC6H4; 1c, 4, R = 4-ClC6H4.
824

SULFONAMIDATION OF HALOGEN-SUBSTITUTED ELECTROPHILES
825
Scheme 2.
H
N
Cl
R
N
Cl
K2CO3, MeCN, ∆
+ RX
Cl
Cl
Cl
Cl
ArSO2
ArSO2
2–4
5, 6a, 6b, 7a–7f
X = I, Br, Cl; 5, Ar = Ph, R = Pr; 6, Ar = 4-MeC6H4, R = Et (a), Pr (b); 7, Ar = 4-ClC6H4, R = Et (a), Pr (b), Bu (c),
CH2=CHCH2 (d), NCCH2 (e), PhCH2 (f).
N-(2,2,2-Trichloroethyl)benzenesulfonamide (2).
N,N-Dichloroamide 1a, 2.49 g (11 mmol), was added
in portions to a solution of 0.97 g (10 mmol) of freshly
distilled 1,1-dichloroethene in 10 mL of chlorobenzene
while continuously bubbling argon through the reac-
tion mixture. The mixture was stirred for 4 h at 100°C
and cooled to room temperature, a solution of 1.14 g
(11 mmol) of sodium hydrogen sulfite in 30 mL of
water was added, the mixture was stirred for 1 h, and
the precipitate was filtered off and dried. Yield 2.42 g
(85%), mp 174–175°C; published data [19]: mp 175–
177°C. IR spectrum, ν, cm–1: 3284 (NH), 1313, 1161
yields of 5–7 were obtained by heating the reactants in
DMF or acetonitrile in the presence of an alkali metal
carbonate. However, the use of DMF complicated the
purification stage, thus making the procedure more
laborious.
Under the given conditions, primary alkyl halides,
allyl halides, chloroacetonitrile, and benzyl chloride
reacted with sulfonamides 2–4, whereas secondary
alkyl halides failed to react, presumably for steric
reasons.
The structure of 5–7 was confirmed by spectral data
and elemental analyses. Compounds 5–7 showed in the
IR spectra absorption bands due to stretching vibra-
tions of SO2 group, while no NH stretching band
typical of initial sulfonamides 2–4 was observed. The
1H and 13C NMR spectra of 5–7 contained signals of
protons and carbon nuclei of the aromatic ring, alkyl or
allyl substituent, and trichloroethyl group. Methylene
protons of the trichloroethyl group gave a two-proton
1
(SO2). H NMR spectrum (DMSO-d6), δ, ppm: 3.91 d
(2H, CH2, 3J = 6.6 Hz), 7.62 m and 7.87 m (5H, C6H5),
3
8.93 t (1H, NH, J = 6.6 Hz). 13C NMR spectrum
(DMSO-d6), δC, ppm: 60.74 (CH2), 99.01 (CCl3);
127.87, 130.54, 133.98, 141.23 (C6H4).
Compounds 3 and 4 were synthesized in a similar
way.
4-Methyl-N-(2,2,2-trichloroethyl)benzenesulfon-
amide (3) was synthesized from 2.64 g (11 mmol) of
N,N-dichloro amide 1b. Yield 2.43 g (73%), mp 140–
142°C; published data [20]: mp 142°C. IR spectrum, ν,
1
singlet in the H NMR spectra, in keeping with the
presumed structure.
Compounds 5–7 were isolated as colorless crystal-
line solids soluble in organic solvents and insoluble in
water. The absence of highly polar NH group increases
the solubility of 5–7 in nonpolar solvents as compared
to initial sulfonamides 2–4.
1
cm–1: 3295 (NH), 1354, 1167 (SO2). H NMR spec-
3
trum (DMSO-d6), δ, ppm: 3.86 d (2H, CH2, J =
6.3 Hz), 7.40 and 7.76 (4H, AA′BB′, C6H4), 8.84 t (1H,
3
13
NH, J = 6.3 Hz). C NMR spectrum (DMSO-d6), δC,
ppm: 60.09 (CH2), 98.04 (CCl3); 128.12, 129.43,
137.65, 140.68 (C6H5).
Molecules 5–7 contain a trichloromethyl group and
a double C=C bond (7d), which makes them promising
as intermediate products in fine organic synthesis and
obvious precursors to synthetic amino acids and
functionalized acyclic and heterocyclic compounds.
4-Chloro-N-(2,2,2-trichloroethyl)benzenesulfon-
amide (4) was synthesized from 2.87 g (11 mmol) of
N,N-dichloro amide 1c. Yield 2.97 g (92%), mp 178–
179°C; published data [18]: mp 179°C. IR spectrum, ν,
1
cm–1: 2976 (NH), 1132, 1164 (SO2). H NMR spec-
EXPERIMENTAL
3
trum (CDCl3), δ, ppm: 3.95 d (2H, CH2, J = 6.7 Hz),
7.68 and 7.89 (4H, AA′BB′, C6H4), 9.02 t (1H, NH, 3J =
6.7 Hz). 13C NMR spectrum (DMSO-d6), δC, ppm:
60.99 (CH2), 98.79 (CCl3); 128.92, 129.84, 138.04,
140.65 (C6H4).
The IR spectra were recorded in KBr on a Bruker
1
IFS-25 spectrometer. The H and 13C NMR spectra
were measured on a Bruker DPX-400 instrument at
400.61 and 100.13 MHz, respectively, using tetra-
methylsilane as internal standard. The elemental
analyses were obtained on a Thermo Scientific Flash
EA1112 CHNS-O/MAS 200 analyzer.
N-Propyl-N-(2,2,2-trichloroethyl)benzenesulfon-
amide (5). A mixture of 1.00 g (3.5 mmol) of com-
pound 2, 0.71 g (4.2 mmol) of 1-iodopropane, and
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 53 No. 6 2017

CHERNYSHEVA et al.
826
0.58 g (4.2 mmol) of calcined potassium carbonate in
10 mL of acetonitrile was stirred for 5 h at 60°C. The
mixture was cooled to room temperature and filtered,
the filtrate was evaporated under reduced pressure, and
the residue was washed with 10% aqueous HCl and
water, dried, and purified by recrystallization from
hexane. Yield 0.96 g (83%), mp 47°C. IR spectrum, ν,
above for amide 6a from 0.60 g (1.9 mmol) of com-
pound 4 and 0.25 g (2.3 mmol) of bromoethane in the
presence of 0.31 g (2.3 mmol) of calcined potassium
carbonate. Yield 0.63 g (95%), mp 102–103°C. IR
spectrum, ν, cm–1: 2968 (C–Haliph), 1334, 1148 (SO2).
1H NMR spectrum (CDCl3), δ, ppm: 1.20 m and
3.57 m (5H, C2H5), 4.31 s (2H, CH2), 7.52 and 7.82
(4H, AA′BB′, C6H4). 13C NMR spectrum (CDCl3), δC,
ppm: 13.06 (CH3), 44.34 (CH2), 63.65 (CH2), 98.04
(CCl3); 128.00, 129.00, 138.00, 139.00 (C6H4). Found,
%: C 34.19; H 3.11; Cl 40.29; N 3.87; S 9.16.
C10H11Cl4NO2S. Calculated, %: C 34.21; H 3.16;
Cl 40.39; N 3.99; S 9.13.
1
cm–1: 2976 (C–Haliph), 1352, 1167 (SO2). H NMR
spectrum (CDCl3), δ, ppm: 0.53 m, 1.40 m, and 3.15 m
(7H, C3H7); 4.07 s (2H, CH2), 7.53 m and 7.62 m (5H,
C6H5). 13C NMR spectrum (CDCl3), δC, ppm: 11.04
(CH3), 21.10 (CH2), 51.11 (CH2), 64.33 (CH2), 98.23
(CCl3); 127.45, 129.23, 133.05, 139.81 (C6H5). Found,
%: C 39.87; H 4.15; Cl 32.31; N 4.23; S 10.01.
C11H14Cl3NO2S. Calculated, %: C 39.96; H 4.27;
Cl 32.17; N 4.24; S 9.70.
4-Chloro-N-propyl-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (7b) was synthesized from 1.00 g
(3.0 mmol) of compound 4 and 0.61 g (3.6 mmol) of
1-iodopropane in the presence of 0.50 g (4.0 mmol) of
calcined potassium carbonate. Yield 0.95 g (84%),
mp 78°C. IR spectrum, ν, cm–1: 2974 (C–Haliph), 1352,
Compounds 6b, 7b, 7c, and 7e were synthesized in
a similar way.
N-Ethyl-4-methyl-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (6a). A mixture of 0.50 g (1.7 mmol)
of compound 3, 0.22 g (2.0 mmol) of bromoethane,
and 0.28 g (2.0 mmol) of calcined potassium carbonate
in 10 mL of acetonitrile was stirred for 7 h at 35°C.
The mixture was then treated as described above in the
synthesis of 5. Yield 0.50 g (82%), mp 93–95°C. IR
spectrum, ν, cm–1: 2975 (C–Haliph), 1532, 1161 (SO2).
1H NMR spectrum (CDCl3), δ, ppm: 1.09 m and
3.46 m (5H, CH2CH3), 2.37 s (3H, CH3), 4.23 s (2H,
CH2), 7.26 and 7.69 (4H, AA′BB′, C6H4). 13C NMR
spectrum (CDCl3), δC, ppm: 12.61 (CH3), 21.08 (CH3),
43.82 (CH2), 63.45 (CH2), 7.85 (CCl3); 126.68, 127.07,
136.67, 144.03 (C6H4). Found, %: C 39.85; H 4.21;
Cl 32.39; N 4.38; S 9.92. C11H14Cl3NO2S. Calculated,
%: C 39.96; H 4.27; Cl 32.17; N 4.24; S 9.70.
1
1161 (SO2). H NMR spectrum (CDCl3), δ, ppm:
0.81 m, 1.65 m, and 3.41 m (7H, C3H7); 4.32 s (2H,
CH2), 7.53 and 7.84 (4H, AA′BB′, C6H4). 13C NMR
spectrum (CDCl3), δC, ppm: 11.19 (CH3), 21.10 (CH2),
51.23 (CH2), 64.22 (CH2), 98.18 (CCl3); 129.05,
129.64, 138.58, 139.74 (C6H4). Found, %: C 30.77;
H 3.21; Cl 33.01; N 3.29; S 7.54. C11H13Cl4NO2S. Cal-
culated, %: C 30.79; H 3.17; Cl 33.05; N 3.26; S 7.47.
N-Butyl-4-chloro-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (7c) was synthesized from 0.90 g
(2.8 mmol) of compound 4 and 0.62 g (3.4 mmol) of
1-iodobutane in the presence of 0.47 g (3.4 mmol) of
calcined potassium carbonate. Yield 0.93 g (91%),
mp 71°C. IR spectrum, ν, cm–1: 2947 (C–Haliph), 1359,
1
1163 (SO2). H NMR spectrum (CDCl3), δ, ppm:
4-Methyl-N-propyl-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (6b) was synthesized from 0.50 g
(1.7 mmol) of compound 3 and 0.34 g (2.0 mmol) of
1-iodopropane in the presence of 0.27 g (2.0 mmol) of
calcined potassium carbonate K2CO3. Yield 0.52 g
(92%), mp 71–73°C. IR spectrum, ν, cm–1: 2938
0.89 m, 1.23 m, 1.63 m, and 3.47 m (9H, C4H9), 4.33 s
(2H, CH2), 7.52 and 7.82 (4H, AA′BB′, C6H4).
13C NMR spectrum (CDCl3), δC, ppm: 13.64 (CH3),
19.96 (CH2), 29.61 (CH2), 49.30 (CH2), 64.06 (CH2),
98.10 (CCl3); 128.95, 129.51, 138.42, 139.62 (C6H4).
Found, %: C 38.08; H 3.89; Cl 39.01; N 4.74; S 8.57.
C12H15Cl4NO2S. Calculated, %: C 38.02; H 3.99;
Cl 38.84; N 3.69; S 8.46.
1
(C–Haliph), 1347, 1153 (SO2). H NMR spectrum
(CDCl3), δ, ppm: 0.79 m, 1.65 m, and 3.39 m (7H,
C3H7); 2.44 s (3H, CH3), 4.29 s (2H, CH2), 7.39, 7.84
(4H, AA′BB′, C6H4). 13C NMR spectrum (CDCl3), δC,
ppm: 10.58 (CH3), 20.53 (CH3), 21.08 (CH2), 50.67
(CH2), 63.93 (CH2), 97.83 (CCl3); 127.04, 129.31,
136.89, 143.41 (C6H4). Found, %: C 41.75; H 4.58;
Cl 31.02; N 4.18; S 9.13. C12H16Cl3NO2S. Calculated,
%: C 41.81; H 4.68; Cl 30.86; N 4.06; S 9.30.
4-Chloro-N-(prop-2-en-1-yl)-N-(2,2,2-trichloro-
ethyl)benzenesulfonamide (7d). A mixture of 1.40 g
(4.3 mmol) of compound 4, 0.62 g (5.2 mmol) of allyl
bromide, and 0.72 g (5.2 mmol) of calcined potassium
carbonate in 10 mL of acetonitrile was stirred for 6 h at
60°C. The mixture was then treated as described above
in the synthesis of 5. Yield 1.40 g (88%), mp 79–80°C.
IR spectrum, ν, cm–1: 1586 (C=C), 1351, 1164 (SO2).
4-Chloro-N-ethyl-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (7a) was synthesized as described
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 53 No. 6 2017

SULFONAMIDATION OF HALOGEN-SUBSTITUTED ELECTROPHILES
827
1H NMR spectrum (CDCl3), δ, ppm: 4.18 d (2H, CH2,
3J = 2 Hz), 4.32 s (2H, CH2), 5.25 m (2H, =CH2),
5.49 m (1H, =CH), 7.51 and 7.84 (4H, AA′BB′, C6H4).
13C NMR spectrum (CDCl3), δC, ppm: 51.18 (2H,
CH2), 62.00 (2H, CH2), 97.80 (CCl3), 121.29 (CH2);
128.63, 129.05, 138.22, 139.29 (C6H4). Found, %:
C 36.32; H 2.98; Cl 39.23; N 4.05; S 8.87.
C11H11Cl4NO2S. Calculated, %: C 36.39; H 3.05;
Cl 39.06; N 4.10; S 8.83.
3. Shainyan, B.A., Chipanina, N.N., Oznobikhina, L.P.,
Chernysheva, G.N., and Rozentsveig, I.B., J. Phys. Org.
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and Kashik, T.V., Russ. J. Org. Chem., 2000, vol. 36,
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Stupina, A.G., Levkovskaya, G.G., and Albanov, A.I.,
Pharm. Chem. J., 2001, vol. 35, no. 6, p. 311.
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tsveig, G.N., Mirskova, A.N., Krivdin, L.B., Larina, L.I.,
and Albanov, A.I., Tetrahedron Lett., 2005, vol. 46,
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7. Rozentsveig, I.B., Popov, A.V., Rozentsveig, G.N.,
Serykh, V.Yu., Chernyshev, K.A., Krivdin, L.B., and
Levkovskaya, G.G., Mol. Diversity, 2010, vol. 14,
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4-Chloro-N-(cyanomethyl)-N-(2,2,2-trichloro-
ethyl)benzenesulfonamide (7e) was synthesized from
0.50 g (1.5 mmol) of compound 4 and 0.14 g
(1.8 mmol) of chloroacetonitrile in the presence of
0.25 g (1.8 mmol) of calcined potassium carbonate.
Yield 0.51 g (94%), mp 112°C. IR spectrum, ν, cm–1:
1
2212 (CN), 1351, 1164 (SO2). H NMR spectrum
(CDCl3), δ, ppm: 4.32 s (2H, CH2), 4.61 s (2H, CH2),
13
7.59 and 7.84 (4H, AA′BB′, C6H4). C NMR spectrum
(CDCl3), δC, ppm: 37.95 (CH2), 64.65 (CH2), 97.08
(CCl3), 113.78 (CN); 129.82, 130.75, 136.36, 144.90
(C6H4). Found, %: C 33.20; H 2.24; Cl 39.19; N 7.80;
S 9.01. C10H8Cl4N2O2S. Calculated, %: C 33.17;
H 2.23; Cl 39.17; N 7.74; S 8.86.
9. Giubellina, N., Mangelinckx, S., Törnroos, K.W., and
De Kimpe, N., J. Org. Chem., 2006, vol. 71, p. 5881.
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Chernyshev, K.A., and Levkovskaya, G.G., Eur. J. Org.
Chem., 2011, vol. 23, p. 4415.
N-Benzyl-4-chloro-N-(2,2,2-trichloroethyl)ben-
zenesulfonamide (7f). A mixture of 0.60 g (1.9 mmol)
of compound 4, 0.28 g (2.3 mmol) of benzyl chloride,
and 0.30 g (2.2 mmol) of calcined potassium carbonate
in 15 mL of acetonitrile was stirred for 5 h at 70°C.
The mixture was then treated as described above in the
synthesis of 5. Yield 0.68 g (91%), mp 96°C. IR spec-
11. Rozentsveig, I.B., Serykh, V.Y., Chernysheva, G.N.,
Chernyshev, K.A., Kondrashov, E.V., Tretyakov, E.V.,
and Romanenko, G.V., Eur. J. Org. Chem., 2013, p. 368.
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Chem., 2014, no. 29, p. 6547.
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Vashchenko, A.V., Smirnov, V.I., and Rozentsveig, I.B.,
Arkivoc, 2015, part (vii), p. 377.
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part (xiii), p. 45.
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1
trum, ν, cm–1: 1350, 1168 (SO2). H NMR spectrum
(CDCl3), δ, ppm: 4.31 s (2H, CH2), 4.84 s (2H, CH2),
7.25 m (3H, C6H5), 7.32 m (2H, C6H5), 7.54 and 7.82
(4H, AA′BB′, C6H4). 13C NMR spectrum (CDCl3), δC,
ppm: 52.56 (CH2), 62.73 (CH2), 98.08 (CCl3); 128.09,
129.25, 129.65, 134.01 (C6H5); 128.95, 129.25,
135.32, 139.03 (C6H4). Found, %: C 43.54; H 3.09;
Cl 34.29; N 3.32; S 7.79. C15H13Cl4NO2S. Calculated,
%: C 43.61; H 3.17; Cl 34.32; N 3.39; S 7.76.
The main results were obtained using the facilities
of the Baikal Joint Analytical Center, Siberian Branch,
Russian Academy of Sciences.
17. Rozentsveig, I.B., Popov, A.V., and Levkovskaya, G.G.,
Russ. J. Org. Chem., 2013, vol. 49, p. 466.
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Robos, V.I., and Freidlina, R.Kh., Bull. Acad. Sci. USSR,
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p. 520.
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