Halogenation of N-substituted p-quinonimines and p-quinone oxime esters: II. Chlorination and bromination of 4-aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclohexadienones

Article abstract of DOI:10.1023/A:1019663122800

Halogenation of 4-aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclohexadienones yields Z, E-isomeric 4-aroyl(arylsulfonyl)oxyimino-5,6-dihalo-2-methyl-2-cyclohexenones and (E)-4-aroyl(arylsulfonyl)oxyimino-5,6-dihalo-6-methyl-2-cyclohexenones. Further chlorination leads to formation of (Z,E)-4-aroyl(arylsulfonyl)oxyimino-2,5,6-trichloro-6-methyl-2-cyclohexenones.

Full text of DOI:10.1023/A:1019663122800

Russian Journal of Organic Chemistry, Vol. 38, No. 5, 2002, pp. 692 698. Translated from Zhurnal Organicheskoi Khimii, Vol. 38, No. 5, 2002,
pp. 729 736.
Original Russian Text Copyright
2002 by Avdeenko, Glinyanaya, Konovalova, Goncharova.
Halogenation of N-Substituted p-Quinonimines
and p-Quinone Oxime Esters: II.* Chlorination
and Bromination of 4-Aroyl(arylsulfonyl)oxyimino-2-methyl-
2,5-cyclohexadienones**
A. P. Avdeenko, N. M. Glinyanaya, S. A. Konovalova, and S. A. Goncharova
Donbass State Mechine-Building Academy, ul. Shkadinova 72, Kramatorsk, 84313 Ukraine
e-mail: chimist@dgma.donetsk.ua
Received April 11, 2001
Abstract Halogenation of 4-aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclohexadienones yields Z,E-iso-
meric 4-aroyl(arylsulfonyl)oxyimino-5,6-dihalo-2-methyl-2-cyclohexenones and (E)-4-aroyl(arylsulfonyl)oxy-
imino-5,6-dihalo-6-methyl-2-cyclohexenones. Further chlorination leads to formation of (Z,E)-4-aroyl(aryl-
sulfonyl)oxyimino-2,5,6-trichloro-6-methyl-2-cyclohexenones.
In our previous communications [1, 2] we reported
on the halogenation of alkyl-substituted 4-aroyl(aryl-
sulfonyl)oxyimino-2,5-cyclohexadienones, which
occurred at either of the quinoid C C bonds. The
substrates were compounds existing as a single isomer
due to the presence of methyl group in the ortho-posi-
tion with respect to the oxyimino group, which did
not undergo Z,E isomerization. Further chlorination
of 4-aroyl(arylsulfonyl)oxyimino-3-methyl(or 2,3-di-
methyl, or 2-isopropyl-5-methyl)-2,5-cyclohexadi-
enones containing chlorine in the quinoid ring gave
chlorine addition products at the chlorine-substituted
double bond [1]. In the chlorination of chlorine-sub-
stituted 4-aroyl(arylsulfonyl)oxyimino-3-methyl(or
2,3-dimethyl)-2,5-cyclohexadienones the addition
occurred at either of the C C bonds. The chlorine-
substituted C C bond was located cis with respect to
the aroyl(arylsulfonyl)oxy group on the nitrogen. The
chlorination of 2-chloro-4-(4-nitrobenzoyloxyimino)-
6-isopropyl-3-methyl-2,5-cyclohexadienone can also
involve either of the two quinoid double bonds, but
the C2 C3 bond occupies trans position with respect
to the substituent on the nitrogen. Taking into account
that the cis-C C bond is more reactive, no addition of
chlorine at the C2 C3 bond should occur. However,
____________
chlorine molecule added at both C2 C3 and C5 C6
bonds of the substrate.
In the present work, we examined halogenation of
4-aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclo-
hexadienones I which exist as Z and E isomers with
a view to elucidate whether would the halogenation
occur at the quinoid C C bond having a chlorine
atom attached thereto and occupying the trans posi-
tion with respect to the substituent on the nitrogen.
Hereinafter, we assume the Z isomer to have structure
A where the aroyloxy or arylsulfonyloxy group is
located cis relative to the quinoid double bond having
a substituent. When substituents are present at both
C C bonds, Z,E isomers of B are defined with
respect to the substituent located in the ortho position
*
For communication I, see [1].
**
This study was financially supported by the EC INTAS
Program (grant no. 00157-1999) and by the Ministry of
Education and Science of Ukraine.
X = ArCO, ArSO2; A, B, Y, Z = Alk, Hlg; C, Y = Alk, Z = Hlg.
1070-4280/02/3805-0692$27.00 2002 MAIK Nauka/Interperiodica

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
693
relative to the imino group. If the substituents occupy
positions 2,6 or 3,5, Z,E isomers are distinguished
according to their rank. For 4-aroyl(arylsulfonyl)oxy-
imino-2-cyclohexenones D, regardless of the number,
nature, and position of substituents, the Z-isomer is
assumed to be that in which the N-aroyloxy or N-aryl-
sulfonyloxy group is located cis with respect to the
double C C bond in the cyclohexene ring.
occurs at the unsubstituted C C bond of the quinoid
ring, yielding either Z or E isomers and in some cases
Z,E-isomeric mixtures of 4-aroyl(arylsulfonyl)oxy-
imino-5,6-dihalo-2-methyl-2-cyclohexenones IIa IId,
IIg, IIIa IIIc, and IIIe IIIg. Previously [3], only
the E isomers of II were isolated in the chlorination
of I. We were the first to obtain halogen addition
products at the methyl-substituted double bond of
Ig, 4-(4-nitrophenylsulfonyl)oxyimino-5,6-dihalo-6-
methyl-2-cyclohexenones IVg and Vg. It should be
noted that this reaction occurs only with the Z isomer
of Ig in which the C2 C3 bond is activated due to
cis arrangement of the 4-NO2C6H4SO2O group on the
nitrogen. The effect of the substituent on the nitrogen
on the reactivity of quinoid double bonds was
revealed for the first time in [4], but no clear explana-
tion was proposed.
X = ArCO, ArSO2; Y = Alk.
Compounds IVg and Vg do not undergo dehydro-
chlorination on treatment with triethylamine in chloro-
form or with sodium acetate in acetic acid, which is
consistent with the dehydrohalogenation regioselec-
tivity rules formulated in [5].
Dehydrohalogenation of compounds II and III
yields 4-aroyl(arylsulfonyl)oxyimino-6-halo-2-methyl-
2,5-cyclohexadienones VIa VId, VIIa VIIc, and
VIIe VIIg. As expected, halogen atom is abstracted
exclusively from the ortho-position with respect to
the carbonyl group.
We previously studied [2, 3] addition of only one
halogen molecule to 4-aroyloxyimino-2-methyl-2,5-
cyclohexadienones. No further halogenation was
examined. Scheme 1 illustrates processes involving
addition of two halogen molecules to 4-aroyl(aryl-
sulfonyl)oxyimino-2-methyl-2,5-cyclohexadienones
Ia Ig. The chlorination of compounds Ia Id and Ig
was carried out using gaseous chlorine and ethanol or
DMF acetic acid mixtures as solvent. The bromina-
tion of Ia Ic and Ie Ig was effected with bromine in
acetic acid. The first halogenation stage (as in [2, 3])
Scheme 1.
X = C6H5CO (a), 4-NO2C6H4CO (b), C6H5SO2 (c), 4-ClC6H4SO2 (d), 4-CH3C6H4SO2 (e), 3-NO2C6H4SO2 (f), 4-NO2C6H4SO2 (g);
II, IV, VI, Hlg = Cl; III, V, VII, Hlg = Br.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

694
AVDEENKO et al.
By chlorination of compounds Ia Ic and Ig under
The structure of compounds II VIII was proved
1
more severe conditions (in DMF AcOH, 3:1) we
obtained products of addition of two chlorine mole-
cules, 4-aroyl(arylsulfonyl)oxyimino-2,5,6-trichloro-
6-methyl-2-cyclohexenones VIIIa VIIIc and VIIIg.
Obviously, the reactions involves intermediate forma-
tion of the corresponding 4-aroyl(arylsulfonyl)oxy-
imino-6-chloro-2-methyl-2,5-cyclohexadienes VI. It
should be noted that, as well as in the halogenation of
Ig, chlorine addition to compounds VI occurs mainly
at the methyl-substituted C C bond of the quinoid
ring of the Z isomer in which this C C bond is
located cis with respect to the XO substituent on the
nitrogen. Addition at the corresponding bond of E
isomer was observed only in the chlorination of oxime
ester Ia, and the fraction of the product was only 15%
of the overall amount of the chlorination products
by elemental analysis (Table 1) and H NNR spec-
troscopy (Table 2). The 13C NMR spectrum of com-
pound IIIc was also recorded. The 3-H signal in the
1H NMR spectra of II and III is observed at 7.24
7.47 ppm (Z isomers) or 6.73 7.16 ppm (E isomers).
It is split into a quartet due to coupling with the
methyl protons; its position is consistent with its
location in the ortho position with respect to the C N
group. The 5-H and 6-H signals are doublets of
doublets and doublets at
4.92 5.74 and 4.43
4.84 ppm, respectively. Their chemical shifts indicate
that these protons are attached to sp3-hybridized
carbon atoms. The 5-H proton is coupled with 6-H
and 3-H, and 6-H, only with 5-H. The 13C NMR spec-
trum of IIIc contains upfield signals from sp3-hy-
1
bridized carbon atoms (CHBr) at
44.79 ppm. The H NMR spectra of IIa and IIIa were
43.55 and
C
(according to the H NMR data). No chlorine addition
1
products at the chlorine-substituted C C bond were
detected.
reported in [2, 3].
1
In the H NMR spectra of IVg and Vg the 2-H
Thus the results of our previous studies [1 3] and
those obtained in the present work suggest that the
direction of halogenation depends not only on the
orientation of XO group on the nitrogen (cis or trans)
and the size of substituents at the C C bond but also
on the nature of these substituents (donor or acceptor)
and their position with respect to the imino group
(ortho or meta). In other words, electron density
distribution in the quinoid ring is an important factor
among those governing halogen addition process.
Finally, we effected chlorination of 2,6-dichloro-4-
phenylsulfonyloxyimino-2,5-cyclohexadienone (IX)
(Scheme 2). Previously, we failed to add chlorine
molecule to 4-arylsulfonyloxyimino-2,6-dichloro-2,5-
cyclohexadienones [6]. This reaction attracts interest
in comparison with the chlorination of compounds I,
which involves intermediate formation of 4-aroyl(aryl-
sulfonyl)oxyimino-6-chloro-2-methyl-2,5-cyclohexa-
dienones VI. The latter take up chlorine only at the
C2 C3 bond to give both Z and E isomers of VIII.
From compound IX (Scheme 2) we obtained only the
corresponding E isomer, 2,5,6,6-tetrachloro-4-phenyl-
sulfonyloxyimino-2-cyclohexenone (X), i.e., the reac-
tion occurs exclusively at the cis-C C bond.
proton appears as a doublet at 6.45 ppm, the 3-H
signal is a doublet of doublets at 6.90 6.94 ppm,
and that from 5-H is a doublet at 5.50 5.70 ppm.
The positions of these signals are consistent with the
assigned structure. The coupling constants between
2-H and 3-H and between 3-H and 5-H are equal to
10.5 and 1.8 Hz, respectively. The 3-H signal of VI
and VII is a quartet at 7.46 7.61 ppm (Z isomers) or
6.90 7.31 ppm (E isomers); the signal from 5-H
is located at 7.27 7.87 ppm (Z isomers) or 7.75
8.20 ppm (E isomers). It is split into a doublet due
to coupling with 3-H. Compounds VIII show in the
1H NMR spectra doublet signals at 7.14 7.49 and
7.82 ppm for the Z and E isomers, respectively. The
5-H signal is a doublet at 5.49 5.62 (Z) or 5.28 ppm
(E isomer). The coupling constants range from 1.5 to
1
1.8 Hz. The H NMR spectrum of X contains two
doublets typical of hydrogen atoms attached to sp2-
and sp3-hybridized carbon atoms of the E isomer.
The IR spectra of oxime esters VIa VId, VIIa
VIIc, and VIIe VIIg are characterized by the pres-
ence of absorption bands in the regions 1660 1655,
1
1610 1585, and 1545 1475 cm , which belong to
stretching vibrations of the C O, C C, and C N
bonds, respectively. The carbonyl absorption band of
compounds II V and VIII has a higher frequency;
and their IR spectra contain bands at 1710 1685
Scheme 2.
1
(C O), 1630 1600 (C C), and 1600 1500 cm
(C N).
On the basis of the data given in [4, 7, 8] and
1
coupling constants in the H NMR spectra we pre-
sumed [3] trans-diaxial arrangement of the chlorine
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
695
Table 1. Melting points and elemental analyses of compounds IIa IId, IIIb, IIIc, IIIe, VIb, VIc, VIIb, VIIc, and
VIIIa VIIIca
Found, %
Calculated, %
Comp.
no.
mp,
C
Formula
Hlg
N
Hlg
N
E-IIa
E-IIb
Z-IIc
Z-IId
212
22.68, 22.79
19.80, 19.97
20.42, 20.50
27.65, 27.83
35.65, 35.88
36.63, 36.83
35.39, 35.40
11.01, 11.29
11.11, 11.32
21.63, 21.74
21.60, 21.72
22.25, 22.37
30.53, 30.75
27.01, 27.12
27.93, 28.14
C14H11Cl2NO3
C14H10Cl2N2O5
C13H11Cl2NO4S
C13H10Cl3NO4S
C14H10Br2N2O5
C13H11Br2NO4S
C14H13Br2NO4S
C14H9ClN2O5
C13H10ClNO4S
C14H9BrN2O5
C14H9BrN2O5
C13H10BrNO4S
C14H10Cl3NO3
C14H9Cl3N2O5
C13H10Cl3NO4S
22.72
19.85
20.36
27.80
35.83
36.56
35.42
11.06
11.37
21.88
21.88
22.43
30.69
27.16
27.80
138
122
151
164
113
119
Z-IIIbb
Z-IIIc
Z-IIIe
E-VIb
E-VIc
Z-VIIb
E-VIIb
Z-VIIc
E-VIIIa
E-VIIIb
E-VIIIc
6.30, 6.38
3.27, 3.32
3.01, 3.20
6.28
3.20
3.10
233 (decomp.)
134
220 (decomp.)
230 (decomp.)
7.47, 7.58
7.76, 7.88
3.98, 4.06
4.08, 4.24
7.03, 7.05
3.76, 3.97
7.67
7.67
3.93
4.04
7.15
3.66
140
130
211
135
a
The melting points and elemental analyses are given for individual Z and E isomers.
The data for the E isomer are given in [2].
b
atoms attached to sp3-hybridized carbon atoms in
cyclohexene structures obtained by chlorination of
p-quinone oxime esters. This assumption was con-
firmed by X-ray diffraction data for the HCCl CClH
fragment [1]. In the present work we obtained cyclo-
hexene structures IV, V, and VIII which possess
an HCCl C(CH3)Cl fragment. In order to determine
its structure (whether the chlorine atoms therein are
also trans-diaxial or not) we performed X-ray analysis
of a single crystal of compound VIIIc. The results
showed that the Cl2 and Cl3 atoms in VIIIc occupy
the axial positions with trans arrangement with
respect to each other and that the 3-H hydrogen atom
and 2-CH3 group are nearly equatorial. The sp3-
Analogous results were obtained for structurally
related 5,6-dichloro-2,6-dimethyl-4-phenylsulfonyl-
oxyimino-2-cyclohexenone (XI) which was synthe-
sized previously by chlorination of 2,6-dimethyl-4-
phenylsulfonyloxyimino-2,5-cyclohexadienone [9].
The C1C2C3C4 fragment in XI is planar within
0.001 . The C5, C6, Cl1, and Cl2 atoms are dis-
ordered by two positions, presumably because of the
lack of stereoselectivity in the chlorine addition at the
quinoid C C bond. Two conformers XIA and XIB
are simultaneously present in a unit cell, their popula-
tions being equal to 68 and 32%, respectively (Fig. 2).
The deviations of the C5 and C6 atoms of conformer
hybridized C5 and C6 atoms deviate by 0.291 and
+0.284 , respectively, from the plane formed by the
1
C1, C2, C3, and C4 atoms. In keeping with the H
NMR data, molecule VIIIc has E configuration where
the phenylsulfonyloxy group is located trans relative
to the cyclohexene C C bond (Fig. 1).
Fig. 1. Structure of the molecule of 2,5,6-trichloro-6-
methyl-4-phenylsulfonyloxyimino-2-cyclohexenone (VIIIc)
according to the X-ray diffraction data.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

696
AVDEENKO et al.
Table 2. 1H NMR spectra of compounds IIa IId, IIg, IIIa IIIc, IIIe IIIg, IVg, Vg, VIa, VIc, VId, VIIb, VIIc,
VIIe VIIg, VIIIa VIIIc, VIIIg and X in DMSO-d6
Chemical shifts , ppm
Comp.
no.
Isomer
(%)
J, Hz
2-H, 2-Me
3-H
5-H
6-H, 6-Me
X
IIa
IIb
IIc
E (100)
E (100)
Z (100)
Z (100)
Z (33)
E (33)
Z (17)
E (83)
Z (100)
E (100)
Z (94)
E (6)
2.12 d
2.14 d
2.06 d
2.08 d
2.05 d
2.09 d
2.17 d
2.13 d
2.19 d
2.15 d
2.07 d
2.04 d
2.10 d
2.00 d
2.11 d
2.01 d
2.11 d
2.06 d
6.45 d
6.45 d
2.21 d
2.16 d
2.13 d
2.08 d
2.14 d
2.08 d
2.24 d
2.18 d
2.13 d
2.08 d
2.13 d
2.02 d
2.16 d
2.10 d
2.15 d
2.09 d
7.16 q
7.16 q
7.31 q
7.30 q
7.31 q
6.80 q
7.47 q
7.12 q
7.42 q
7.11 q
7.28 q
6.78 q
7.26 q
6.79 q
7.24 q
6.73 q
7.26 q
6.74 q
5.64 d.d
5.62 d.d
4.95 d.d
4.93 d.d
4.92 d.d
5.47 d.d
5.46 d.d
5.74 d.d
5.44 d.d
5.71 d.d
5.01 d.d
5.56 d.d
5.09 d.d
5.57 d.d
5.09 d.d
5.53 d.d
5.08 d.d
5.57 d.d
4.51 d
4.53 d
4.48 d
4.51 d
4.52 d
4.43 d
4.83 d
4.71 d
4.84 d
4.72 d
4.70 d
4.60 d
4.69 d
4.60 d
4.71 d
4.62 d
4.72 d
4.61 d
1.86 s
2.04 s
7.30 8.12 m
8.29 8.41 d.d
7.56 8.04 m
7.55 7.97 d.d
8.21 8.46 d.d
J5, 6 = 2.7, J3, Me = 1.2
J5, 6 = 2.7, J3, Me = 1.2
J5, 6 = 3.2, J3, Me = 1.8
J5, 6 = 3.3, J3, Me = 1.2
J5, 6 = 3.0, J3, Me = 1.8
IIda
IIg
IIIa
IIIb
IIIc
IIIe
IIIf
IIIg
7.52 8.15 m
J5, 6 = 2.4, J3, Me = 1.8
J5, 6 = 3.0, J3, Me = 1.5
J5, 6 = 3.0, J3, Me = 1.5
J5, 6 = 2.4, J3, Me = 1.5
J5, 6 = 2.7, J3, Me = 1.8
8.29 8.41 d.d
8.30 8.42 d.d
7.56 8.02 m
Z (95)
E (5)
7.27 7.90 d.d, J5, 6 = 2.8, J3, Me = 2.0
2.49 s (CH3)
7.79 8.86 m
8.20 8.45 d.d
Z (79)
E (21)
Z (71)
E (20)
E (34)
E (9)
Z (17)
E (83)
Z (64)
E (36)
Z (47)
E (53)
Z (36)
E (64)
Z (96)
E (4)
Z (78)
E (22)
Z (77)
E (23)
Z (75)
E (25)
E (85)
E (15)
E (100)
E (100)
E (100)
E (40)
J5, 6 = 2.8, J3, Me = 1.9
J5, 6 = 3.0, J3, Me = 1.5
IVg
Vg
VIa
6.94 d.d 5.50 d
6.90 d.d 5.70 d
8.21 8.46 d.d
8.20 8.45 d.d
7.54 8.16 m
J2, 3 = 10.5, J3, 5 = 1.8
J2, 3 = 10.5, J3, 5 = 1.8
J3, Me = 1.5, J3, 5 = 2.4
7.72 q
7.32 q
7.47 q
6.98 q
7.46 q
6.97 q
7.61 q
7.31 q
7.48 q
6.98 q
7.47 q
6.95 q
7.47 q
6.90 q
7.46 q
6.95 q
7.49 d
7.82 d
7.49 d
7.15 d
7.14 d
7.22 d
7.62 d
7.96 d
7.28 d
7.78 d
7.27 d
7.96 d
7.87 d
8.20 d
7.54 d
7.75 d
7.53 d
8.08 d
7.52 d
8.00 d
7.51 d
8.05 d
5.62 d
5.28 d
5.59 d
5.49 d
5.49 d
5.81 d
VIc
7.58 8.04 m
7.56 7.98 d.d
8.32 8.43 d.d
7.58 8.04 m
J3, Me = 1.2, J3, 5 = 2.4
J3, Me = 1.2, J3, 5 = 2.4
J3, 5 = 2.4a
VId
VIIb
VIIc
VIIe
VIIf
VIIg
VIIIa
J3, Me = 1.5, J3, 5 = 2.4
7.36 7.92 d.d, J3, Me = 1.7, J3, 5 = 2.5
2.47 s (CH3)
8.32 8.88 m
8.22 8.45 d.d
7.54 8.16 m
J3, Me = 1.5, J3, 5 = 2.4
J3, Me = 1.8, J3, 5 = 2.5
J3, 5 = 1.5
2.01 s
2.02 s
2.01 s
1.90 s
1.93 s
VIIIb
VIIIc
VIIIg
X
8.29 8.43 d.d
7.53 8.01 m
8.20 8.46 d.d
7.60 8.07 m
J3, 5 = 1.5
J3, 5 = 1.7
J3, 5 = 1.8
J3, 5 = 1.8
b
We failed to determine J3,Me
.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
Table 3. Chlorination of quinone oxime esters Ia Id and Ig
697
Initial
compound
Temperature,
C
Solvent
cI, M
Products (isomer fraction, %)a
Ia
Ib
Ic
DMF AcOH (3: 1)
DMF AcOH (3: 1)
DMF AcOH (1: 1)
DMF AcOH (3: 1)
DMF AcOH (1: 1)
DMF AcOH (3: 1)
EtOH
DMF AcOH (1: 1)
EtOH
DMF AcOH (5: 1)
DMF AcOH (3: 1)
0.6
0.2
0.3
0.5
0.5
0.4
0.4
0.3
0.3
0.3
0.5
40 50
40 50
45
30 40
40
60
20
60
25
IIa (E, 100)b, VIIIa (Z, 100)c
VIIIa (E, 85; Z, 15)d
IIb (E, 100)d
VIIIb (E, 100)e
IIc (Z, 100)d
VIIIc (E, 100)c
VIc (Z, 64; E, 36)e
IId (Z, 100)d
Id
Ig
VId (Z, 47; E, 53)e
IIg (Z, 33; E, 33), IVg (E, 34)d
60
50
IIg (Z, 10), IVg (E, 22), VIIIg (E, 68)d
a
b
c
d
e
According to the 1H NMR data.
The product precipitated immediately after chlorination.
The product was isolated by adding water to the filtrate.
The product was isolated by adding water to the reaction solution.
The product precipitated after 3 days.
XIA from the mean-square plane formed by the C1,
C2, C3, and C4 atoms are +0.252 and 0.434 , re-
spectively; the corresponding values for XIB are
0.327 and +0.113 . In both conformers the chlorine
atoms occupy axial positions and are arranged trans
with respect to each other. The hydrogen atom and
methyl group are nearly equatorial. Molecule XI has
E configuration with the C6H5SO2O group located
trans relative to the cyclohexenone double bond.
and 28 <
< 30 for XI. The structures were solved
by the direct method and were refined by the least-
squares procedure in full-matrix anisotropic approxi-
mation using SHELXS and SHELXL-93 software
[10, 11]. All hydrogen atoms were visualized objec-
tively but were included in the calculations with fixed
thermal and positional parameters.
4-Aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclo-
hexadienones Ia Ig were synthesized by acylation of
2-methyl-1,4-benzoquinone 4-oxime with the corre-
sponding aroyl or arenesulfonyl chlorides in diethyl
ether in the presence of triethylamine, following the
procedure reported in [12]. Newly synthesized
quinone oxime esters Ic Ig were mixtures of Z and
EXPERIMENTAL
The IR spectra were recorded on a UR-20 spectro-
photometer in KBr. The 1H NMR spectra were
measured on a Varian VXR-300 instrument at
300 MHz using CDCl3 as solvent and TMS as internal
reference. The 13C NMR spectrum of compound IIIc
was obtained on the same instrument at 75.4 MHz in
CDCl3 relative to TMS. The reaction mixtures were
analyzed by TLC on Silufol UV-254 plates using
benzene ethyl acetate (10:1) as eluent; spots were
visualized by UV irradiation.
X-Ray diffraction data for single crystals of VIIIc
and XI (monoclinic) were obtained at room tem-
perature using an Enraf Nonius CAD-4 four-circle
automatic diffractometer [ MoK irradiation for
VIIIc and CuK for XI, graphite monochromator,
scan rate ratio /2 1.2]. The parameters of unit cells
and crystal orientation matrices were determined from
22 reflections with 12 < < 13 for compound VIIIc
Fig. 2. Structure of the molecule of 5,6-dichloro-2,6-di-
methyl-4-phenylsulfonyloxyimino-2-cyclohexenone (XI)
according to the X-ray diffraction data.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

698
AVDEENKO et al.
E isomers; according to the data of elemental analysis,
they contain no products of different elemental com-
position.
refluxed for several minutes. It was then cooled, and
the product was filtered off and recrystallized from
glacial acetic acid.
Chlorination of quinone oxime esters Ia Id and
Ig (Table 3). Chlorine was passed at a flow rate of
15 20 ml/min through a 0.2 0.6 M solution of com-
pound Ia Id or Ig in 5 ml of appropriate solvent until
saturation. The product was filtered off and recrystal-
lized from acetic acid.
Chlorination of 2,6-dichloro-4-phenylsulfonyl-
oxyimino-2,5-cyclohexadienone (IX). A solution of
1.4 mmol of compound IX was dissolved in 3 ml of
DMF, and the solution was saturated with chlorine
at a flow rate of 15 20 ml/min (60 C). The precipitate
was filtered off and recrystallized from acetic acid.
The product contained 60% of unchanged initial
compound IX and 40% of E-X (according to the
1H NMR data.
REFERENCES
1. Avdeenko, A.P., Glinyanaya, N.M., Konovalo-
va, S.A., Shishkina, S.V., and Goncharova, S.A.,
Russ. J. Org. Chem., 2002, vol. 38, no. 5, pp. 683
691.
2. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Russ. J. Org. Chem., 1995, vol. 31, no. 10,
pp. 1380 1385.
3. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Russ. J. Org. Chem., 1996, vol. 32, no. 1,
pp. 85 89.
4. Baldwin, J.E. and Norris, R.K., J. Org. Chem., 1981,
vol. 46, no. 4, pp. 697 703.
Bromination of quinone oxime esters Ia Ic and
Ie Ig. A 5 M solution of bromine in acetic acid was
added dropwise under vigorous stirring to 5 ml of
a 0.2 M solution of compound Ia Ic or Ie Ig, the
ratio I:Br2 being 1:3. The mixture was heated until
the initial oxime ester dissolved. It was then cooled
to room temperature and poured onto ice, and the
precipitate was filtered off and recrystallized from
glacial acetic acid. Compounds IIIa IIIc, IIIe, and
IIIf were thus obtained. In the bromination of Ig
we isolated a mixture of products IIIg and Vg.
5. Avdeenko, A.P., Zhukova, S.A., and Konovalo-
va, S.A., Russ. J. Org. Chem., 2001, vol. 37, no. 3,
pp. 382 387.
6. Avdeenko, A.P. and Glinyanaya, N.M., Russ. J. Org.
Chem., 1995, vol. 31, no. 11, pp. 1507 1513.
7. Avdeenko, A.P., Velichko, N.V., and Romanen-
ko, E.A., Zh. Org. Khim., 1991, vol. 27, no. 11,
pp. 2350 2361.
8. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, Zh. Org. Khim., 1993, vol. 29, no. 7, pp. 1402
1411.
Dehydrohalogenation of compounds IIa IId,
IIIa, IIIc, and IIIe IIIg. a. Triethylamine, 0.10
0.15 ml, was added to a solution of 1 mmol of com-
pound IIa, IIb, or IIIe IIIg in a minimal amount of
chloroform, and the mixture was heated to the boiling
point. It was then cooled to room temperature, and
the precipitate was filtered off, washed with a small
amount of acetic acid and water, and recrystallized
from glacial acetic acid.
9. Avdeenko, A.P., Zhukova, S.A., Glinyanaya, N.M.,
and Konovalova, S.A., Russ. J. Org. Chem., 1999,
vol. 35, no. 4, pp. 560 571.
10. Sheldric, G.M., SHELXS-86. Program for the Solu-
tion of Crystal Structures, Gottingen: Univ. of
Gottingen, 1986.
11. Sheldric, G.M., SHELXL-93. Program for the Refine-
ment of Crystal Structures, Gottingen: Univ. of
Gottingen, 1993.
b. Sodium acetate, 1 mmol, was added to a solu-
tion of 1 mmol of compound IIc, IId, or IIIa IIIc in
a minimal amount of acetic acid, and the mixture was
12. Titov, E.A. and Burmistrov, S.I., Ukr. Khim. Zh.,
1960, vol. 26, no. 6, pp. 744 749.
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