Reaction of polyhalo semiquinoid structures originating from 4-aroyl(arylsulfonyl)oximino-2,5-cyclohexadiene-1-ones with arylsulfinic acids

Article abstract of DOI:10.1023/A:1012395400078

Stable semiquinoid structures, 4-aroyl(arylsulfonyl)oximino-2,6-dimethyl-5,6-dichloro-2-cyclohexen-1-ones, do not react with dialkyl phosphites, alcohols, tosylhydrazine, p-toluidine, and hydrazoic acid. In reactions with arylsulfinic acids occurs a nucleophilic substitution of chlorine at the sp³-hybridized C⁵ carbon in the minor Z-isomer yielding 4-aroyl(arylsulfonyl)oximino-5-arylsulfonyl-2,6-dimethyl-6-chloro-2-cyclohexen-1-ones.

Full text of DOI:10.1023/A:1012395400078

Russian Journal of Organic Chemistry, Vol. 37, No. 2, 2010, pp. 281 283. Translated from Zhurnal Organicheskoi Khimii, Vol. 37, No. 2, 2001,
pp. 294 296.
Original Russian Text Copyright
2001 by Avdeenko, Zhukova.
Reaction of Polyhalo Semiquinoid Structures Originating
from 4-Aroyl(arylsulfonyl)oximino-2,5-cyclohexadiene-1-ones
with Arylsulfinic Acids
A. P. Avdeenko and S. A. Zhukova
Donbass State Machinebuilding Academy, Kramatorsk, 84313 Ukraine
Received January 14, 1999
Abstract Stable semiquinoid structures, 4-aroyl(arylsulfonyl)oximino-2,6-dimethyl-5,6-dichloro-2-cyclo-
hexen-1-ones, do not react with dialkyl phosphites, alcohols, tosylhydrazine, p-toluidine, and hydrazoic acid.
In reactions with arylsulfinic acids occurs a nucleophilic substitution of chlorine at the sp3-hybridized C5
carbon in the minor Z-isomer yielding 4-aroyl(arylsulfonyl)oximino-5-arylsulfonyl-2,6-dimethyl-6-chloro-
2-cyclohexen-1-ones.
As known the halogenation of 4-aroyl(arylsulfonyl)- genated due to the lack of proton in position 6 [4, 5].
oximino-2,5-cyclohexadiene-1-ones results in the
opening of the quinoid ring due to addition of one
halogen molecule to the double bond in the quinoid
ring [1 5]. As a result arises a mixture of
Z,E-isomers of 4-aroyl(arylsulfonyl)oximino-2,6-
dimethyl-5,6-dihalo-2-cyclohexen-1-ones with one of
them prevailing due to the nonequivalence of the
double bonds of the quinoid ring. The more active
bond is that between the C5 and C6 atoms, namely the
cis-C=C bond with respect to OR substituent at the
nitrogen atom [6, 7].
The obtained stable semiquinoid structures originat-
ing from p-quinone oximes provided a possibility to
study their reactivity.
The most characteristic reactions for semiquinoid
structures originating from N-arylsulfonyl-p-quinone
imines are 1,2-addition, elimination of Cl2 molecule
to yield a quinoid structure that might be further
reduced into the corresponding N-substituted
p-aminophenol, and also the nucleophilic substitution
of chlorine at sp2-hybridized carbon atom [8].
As revealed the study the stable semiquinoid
structures,
4-aroyl(arylsulfonyl)oximino-2,6-di-
methyl-5,6-dichloro-2-cyclohexen-1-ones (Ia d), did
not react with dialkyl phosphites, alcohols, tosyl-
hydrazine, p-toluidine, and hydrazoic acid. In
reactions of compounds Ia d with arylsulfinic acids
occurs a nucleophilic substitution of chlorine at the
sp3-hybridized C5 carbon in the minor Z-isomer (the
OR substituent at nitrogen is in cis- position with
respect to the C=C bond of the semiquinoid ring).
As a result in all cases forms a mixture of the initial
E-isomer of compound Ia d and the reaction product
of the Z-isomer and arylsulfinic acid, 4-aroyl(aryl-
sulfonyl)oximino-5-arylsulfonyl-2,6-dimethyl-6-
chloro-2-cyclohexen-1-one (IIa h) (see scheme).
In the halogenation products of the 4-aroyl(aryl-
sulfonyl)oximino-2,5-cyclohexadiene-1-ones prevails
the E-isomer since the OR substituent at nitrogen is
in transoid position with respect to the C=C bond of
the semiquinoid ring.
The reaction product IIe obtained from compound
Ic and benzenesulfinic acid was identified by
1H NMR spectrum (see Table). According to
1H NMR spectrum the original compound 4-phenyl-
sulfonyloximino-2,6-dimethyl-5,6-dichloro-2-cyclo-
hexen-1-one (Ic) is a mixture of Z- and E-isomers
with the latter prevailing (70%). The reaction product
The halogenation products can be selectively
dehydrohalogenated with elimination of proton from
6 position [1 5]. On addition of one Hlg2 molecule
to 4-aroyl(arylsulfonyl)oximino-2,6(2,5)-cyclohexadi-
ene-1-ones Arise stable structures 4-aroyl(aryl-
sulfonyl)oximino-2,6(2,5)-dimethyl-5,6-dihalo-2-
cyclohexen-1-ones
that cannot be dehydrohalo-
1070-4280/01/3702-0281$25.00 2001 MAIK Nauka/Interperiodica

282
AVDEENKO, ZHUKOVA
Scheme.
I, R = C6H5CO (a), 4-ClC6H4CO (b), C6H5SO2 (c), 3-NO2C6H4SO2 (d); II, R = C6H5CO (a, b), 4-ClC6H4CO (c, d),
C6H5SO2 (e, f), 3-NO2C6H4SO2 (g, h); Ar = C6H5 (a, c, e, g), 4-CH3C6H4 (b, d, f, h).
consists of the initial E-isomer of compound Ic (73%)
and 4-phenylsulfonyloximino-5-phenylsulfonyl-2,6-
dimethyl-6-chloro-2-cyclohexen-1-one (IIe) (27%) as
Z-isomer formed by nucleophilic replacement of
chlorine (see Table). In the other cases the formation
of compounds II was revealed by TLC. In the
1H NMR spectra of recrystallized reaction products
appeared only the E-isomer of the original imino-
ketone I. The reaction product II due to its low
content and higher solubility at recrystallization
remained in the filtrate as showed also TLC. Com-
pounds II were not isolated as individual substances.
No reaction between the E-isomers of compounds
Ia d and arylsulfinic acids is due to steric hindrance:
The sterically shielded chlorine atom does not
undergo nucleophilic substitution with a bulky ArSO2
group.
with liberation of Br2 molecule as we have previously
observed at dehydrobromination [3, 5]. As a result
arise the initial 4-aroyl(arylsulfonyl)oximino-2,6-
dimethyl-2,5-cyclohexadiene-1-ones (Va d) [5].
R = C6H5CO (a), 4-ClC6H4CO (b), C6H5SO2 (c),
3-NO2C6H4SO2 (d).
EXPERIMENTAL
1H NMR spectra were registered on a spectrometer
Varian VXR-300 (300 MHz) in CDCl3, reference
TMS. The initial compounds Ia d, IVa d were
prepared as in [5]. The composition of reaction
products and filtrates after recrystallization were
determined by TLC on Silufol UV-254 plates (eluent
benzene ethyl acetate, 10:1), development under
UV light.
In 4-aroyl(arylsulfonyl)oximino-5,6-dimethyl-
2,5,6-trichloro-2-cyclohexen-1-ones (IIIa, b) that
exist exclusively as Z-isomers the nucleophilic sub-
stitution of chlorine at the sp3-hybridized carbon C5
does not occur apparently due to the steric hindrance
effected by CH3 group.
Reaction
between
4-benzoyl(phenylsulfonyl)-
oximino-2,6-dimethyl-5,6-dichloro-2-cyclohexen-1-
ones (Ia, c) and dialkyl phosphites (a), alcohols (b),
tosylhydrazine (c), hydrazoic acid (d), p-toluidine
(d). (a) To 0.4 ml of dialkyl phosphite (dimethyl
phosphite, diethyl phosphite, diisopropyl phosphite)
was added 0.2 g of the original compound Ia, c. The
reaction mixture was heated to 130 C. The compound
added dissolved, the solution got dark color.
R = C6H5CO (a), 4-ClC6H4CO (b).
The stable semiquinoid structures 4-aroyl(aryl-
sulfonyl)oximino-5,6-dibromo-2,6-dimethyl-2-cyclo-
hexen-1-ones (IVa d) react with arylsulfinic acids
(b) In 5 ml of anhydrous alcohol (methanol,
ethanol, 2-propanol) was refluxed for 1 h 5 mmol of
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 2 2001

REACTION OF POLYHALO SEMIQUINOID STRUCTURES
283
1H NMR spectra (CDCl3) of 4-phenylsulfonyloximino-2,6-dimethyl-5,6-dichloro-2-cyclohexen-1-one (Ic) and
4-phenylsulfonyloximino-2,6-dimethyl-6-chloro-5-phenylsulfonyl-2-cyclohexen-1-one (IIe)
Compd.
no.
Isomer
content,
%
, ppm
H3
J, Hz
CH3C2
CH3C6
H5 (PhSO2C5)
R
Initial
compounds
Z-Ic
30
70
2.07 d
2.02 d
1.85 s
1.85 s
7.26 q
6.76 q
4.90 d
5.47 d
7.58 8.02 m J(H3 H5) 1.5
7.58 8.02 m J(H3 H5) 1.5
E-Ic
Reaction
products
Z-IIe
27
73
2.26 s
2.02 d
2.15 s
1.85 c
6.70 s
6.76 q
5.08 s
(7.52 8.02 m)
5.47 d
7.52 8.02 m
E-Ic
7.58 8.02 m J(H3 H5) 1.5
compound Ia, c. (c) To a solution of 5 mmol of com-
pound Ia, c in 5 ml of ethanol was added 10 mmol of
tosylhydrazine, and the mixture was boiled for 15
20 min. d. To a solution of 2.5 mmol of compound
Ia, c in 10 ml of acetic acid was added 5 mmol of
sodium azide, and the mixture was boiled for 5
10 min. e. To a solution of 5 mmol of compound
Ia, c in 7 ml of ethanol was added 15 mmol of
p-toluidine, and the mixture was boiled for 30 min.
above. The reaction progress was monitored by
TLC. We isolated the initial compounds.
Reaction between 4-aroyl(arylsulfonyl)oximino-
5, 6-dibromo-2,6-dimethyl-2-cyclohexen-1-ones
(IIa d) and arylsulfinic acids was carried out as
above. Yields of compounds, %: Va 60, Vb 53, Vc
74, Vd 41.
REFERENCES
On cooling the reaction mixtures separated a
precipitate that was filtered off and recrystallized
from acetic acid. We isolated the initial compounds.
1. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Zh. Org. Khim., 1993, vol. 25, no. 7,
pp. 1402 1411.
Reaction between 4-aroyl(arylsulfonyl)oximino-
2, 6-dimethyl-5,6-dichloro-2-cyclohexen-1-ones
(Ia d) and arylsulfinic acids. To a solution of an
appropriate initial compound in 10 ml of boiling
acetic acid was added 6 mmol of sodium aryl-
sulfinate, and the mixture was boiled for 3 5 min.
The reaction progress was monitored by TLC. On
cooling to the reaction mixture was added 2 3 ml
of water. The separated precipitate was filtered off
and recrystallized from acetic acid. In reaction of
compound Ic with sodium benzenesulfinate was
isolated a mixture of compounds E-Ic and IIe, in the
rest of experiments were isolated the E-isomers of
compounds Ia, b, d.
2. Avdeenko, A.P. and Glinyanaya, N.M., Zh. Org.
Khim., 1995, vol. 31, no. 11, pp. 1679 1685.
3. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Zh. Org. Khim., 1995, vol. 31, no. 10,
pp. 1523 1529.
4. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Zh. Org. Khim., 1996, vol. 32, no. 1,
pp. 96 100.
5. Avdeenko, A.P., Zhukova, S.A., Glinyanaya, N.M.,
and Konovalova, S.A., Zh. Org. Khim., 1999, vol. 35,
no. 4, pp. 586 596.
6. Baldwin, J.E. and Norris, R.K., J. Org. Chem., 1981,
vol. 46, no. 6, pp. 697 703.
7. Perrin, C.L. and Engler, R.E., J. Org. Chem., 1997,
vol. 62, no. 3, pp. 687 692.
8. Avdeenko, A.P. and Yusina, A.L., Zh. Org. Khim.,
1993, vol. 29, no. 7, pp. 1394 1401.
Reaction between 4-aroyl(arylsulfonyl)oximino-
5,6-dimethyl-2,5,6-trichloro-2-cyclohexen-1-ones
(IIIa,b) and arylsulfinic acids was carried out as
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 2 2001