Unexpected transformations of arenesulfonic acids N-(1-aryl-2,2,2- trichloroethyl)amides in the presence of alkylthiols

Full text of DOI:10.1134/S1070428007100260

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2007, Vol. 43, No. 10, pp. 1559−1560. © Pleiades Publishing, Ltd., 2007.
Original Russian Text © I.B. Rozentsveig, A.V. Popov, A.N. Mirskova, G.G. Levkovskaya, 2007, published in Zhurnal Organicheskoi Khimii, 2007,
Vol. 43, No. 10, pp. 1562−1563.
SHORT
COMMUNICATIONS
Unexpected Transformations of Arenesulfonic Acids
N-(1-Aryl-2,2,2-trichloroethyl)amides in the Presence of Alkylthiols
I. B. Rozentsveig, A. V. Popov, A. N. Mirskova, and G. G. Levkovskaya
Faworsky Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, 664033 Russia
e-mail: i_roz@irioch.irk.ru
Received June 6, 2007
DOI: 10.1134/S1070428007100260
In this process evidently mercaptan is a reducer that
is oxidized into the corresponding disulfide.
We formerly demonstrated [1] that accessible arene-
sulfonic acids N-(1-aryl-2-polychloroethyl)amides [2, 3]
in aprotic highly polar media in the presence of inorganic
bases suffered cyclization into chlorine-containing
N-sulfonylaziridines whose further transformations
essentially depended on the reagents character and
conditions.
4-Chloro-N-[2-(4-chlorophenyl)acetyl]benzene-
sulfonamide (IIa). For 1 h a mixture was stirred at 100°C
of 2.17 g (5 mmol) of 4-chlorobenzenesulfonic acid
N-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]amide (Ia),
2.12 g (20 mmol) of Na2CO3, 1.56 g (20 mmol) of
mercaptoethanol or 1.52 g (20 mmol) of propanethiol in
15 ml of DMF. The reaction mixture was cooled, diluted
with 50 ml of water, filtered, the filtrate was acidified
with 10% hydrochloric acid till neutral, the reaction
mixture was left standing for 24 h, the formed precipitate
of compound IIa was separated, dried, washed with cold
ether till colorless washings, and recrystallized from
hexane. Yield 0.88 g (51%), mp 206–208°C. IR spectrum,
ν, cm–1: 1170, 1360 (SO2), 1690 (C=O), 3100 (NH).
1H NMR spectrum (DMSO-d6), δ, ppm: 3.58 s (2H, CH2),
7.17, 7.33 AA'BB' (4H, C6H4), 7.68, 7.89 AA'BB' (4H,
C6H4), 12.45 br.s (1H, NH). 13C NMR spectrum (DMSO-
d6), δ, ppm: 41.38 (CH2), 128.51, 129.57, 129.78, 131.51,
We discovered uncommon transformations occurring
in DMF in the presence of sodium carbonate and
propanethiol or mercaptoethanol. It was shown by an
example of compounds Ia and Ib with the above thiols
that the process proceeded with the formation of aryl-
acetic acids N-arenesulfonamides IIa and IIb whose
structure was unambiguously proved by spectral methods
and confirmed by elemental analysis.
Apparently dichloroaziridine intermediates A undergo
recyclization into imidoylchloride intermediates B [1]
that under the reaction conditions are hydrolyzed at the
imidoylchloride moiety and are reduced involving the
chloromethyl group.
O
Ar
O
Ar
CH
O
O
Cl
Cl
Cl
O
O
Na2CO3, DMF
_HCl
HC
S
C Cl
S
_
N
4-ClC6H4
C
S
N
+
N
4-ClC6H4
C
Ar
4-ClC6H4
C
Cl
Cl
H
H
Cl
Ia, Ib
A
O
C
O
O
S
O
O
O
Cl
O
Ar
Cl
O
S
HSR
H2O
_HCl
4-ClC6H4
N
C
Ar
4-ClC6H4
N
C
C
Ar
H
S
_[R_S_S_R],
_HCl
H
С
C
4-ClC6H4
N
Cl
H
H
H
H
B
IIa, IIb
Ar = 4-ClC6H4 (a), 4-MeOC6H4 (b); R = Pr, CH2CH2OH
1559

ROZENTSVEIG et al.
1560
1H and 13C NMR spectra were registered on
a spectrometer Bruker DPX-400 (400.6, 100.61 MHz
respectively), internal reference HMDS. IR spectra were
recorded on a spectrophotometer Bruker IFS-25 from
samples pelletized with KΒr.
131.95, 132.96, 138.14, 138.97 (2C6H4), 169.56 (C=O).
Found, %: C 48.57; Cl 20.78 N 4.35; S 9.01.
C14H11Cl2NO3S. Calculated, %: C 48.85; Cl 20.60; N
4.07; S 9.31.
4-Chloro-N-[2-(4-methoxyphenyl)acetyl]benzene-
sulfonamide (IIb) was similarly obtained from 2.15 g
(5 mmol) of amide Ib. Yield 0.73 g (43%), mp 137–
140°C. IR spectrum, ν, cm–1: 1170, 1365 (SO2), 1680
(C=O), 3150 (NH). 1H NMR spectrum (CDCl3), δ, ppm:
3.53 s (2H, CH2), 3.80 s (3H, OCH3), 6.85, 7.06 AA'BB'
and 7.49, 7.94 AA'BB' (8H, 2C6H4), 8.55 br.s (1H, NH).
13C NMR spectrum (CDCl3), δ, ppm: 42.33 (CH2), 54.93
(CH3), 114.32, 123.59, 128.91, 129.54, 130.11, 136.30,
140.40, 158.99 (2C6H4), 168.74 (C=O). Found, %:
C 53.37; Cl 10.12; N 4.29; S 9.28. C15H14ClNO4S.
Calculated, %: C 53.02; Cl 10.43; N 4.12; S 9.44.
REFERENCES
1. Rozentsveig, I.B., Levkovskaya, G.G., Rozentsveig, G.N.,
Mirskova, A.N., Krivdin, L.B., Larina, L.I., and Albanov,
A.I., Tetrahedron Lett., 2005, vol. 46, p. 8889.
2. Rozentsveig, I.B., Levkovskaya, G.G., Albanov, A.I., and
Mirskova, A.H., Zh. Org. Khim., 2000, vol. 36, p. 698.
3. Aizina, Yu.A., Rozentsveig, I.B., Levkovskaya, G.G.,
Rozentsveig, G.N., and Mirskova, A.N., Zh. Org. Khim.,
2002, vol. 38, p. 256.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 43 No. 10 2007