Halogenation of N-substituted p-quinonimines and p-quinone oxime esters: I. Chlorination and bromination of 4-aroyloxyimino- and arylsulfonyloxyimino-2,5-cyclohexadienones

Article abstract of DOI:10.1023/A:1019611105962

Chlorine and bromine addition to 4-aroyloxyimino- and 4-arylsulfonyloxymino-3-methyl-2,5-cyclohexadienones initially occurs at the C⁵=C⁶ double bond. The second chlorine molecule adds at both C²=C³ and C⁵=^C6 double bonds. The chlorination of 2,5-dialkyl-substituted 4-aroyloxyimino- and 4-arylsulfonyloxymino-2,5-cyclohexadienones involves either of the C=C bonds in the quinoid ring.

Full text of DOI:10.1023/A:1019611105962

Russian Journal of Organic Chemistry, Vol. 38, No. 5, 2002, pp. 683 691. Translated from Zhurnal Organicheskoi Khimii, Vol. 38, No. 5, 2002,
pp. 720 728.
Original Russian Text Copyright
2002 by Avdeenko, Shishkina, Shishkin, Glinyanaya, Konovalova, Goncharova.
Halogenation of N-Substituted p-Quinonimines
and p-Quinone Oxime Esters:
I. Chlorination and Bromination of 4-Aroyloxyimino-
and Arylsulfonyloxyimino-2,5-cyclohexadienones*
1
2
2
1
A. P. Avdeenko , S. V. Shishkina , O. V. Shishkin , N. M. Glinyanaya ,
1
1
S. A. Konovalova , and S. A. Goncharova
1
Donbass State Machine-Building Academy, ul. Shkadinova 72, Kramatorsk, 84313 Ukraine
e-mail: chimist@dgma.donetsk.ua
2
Research Department of Alkali Metal Halide Crystals, Institut monokristallov Research
and Technological Concern, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Received March 16, 2001
Abstract Chlorine and bromine addition to 4-aroyloxyimino- and 4-arylsulfonyloxymino-3-methyl-2,5-
cyclohexadienones initially occurs at the C5 C6 double bond. The second chlorine molecule adds at both
C2 C3 and C5 C6 double bonds. The chlorination of 2,5-dialkyl-substituted 4-aroyloxyimino- and 4-aryl-
sulfonyloxymino-2,5-cyclohexadienones involves either of the C C bonds in the quinoid ring.
In the previous communications we reported the
results of our studies on chlorination and bromination
of N-arylsulfonyl-1,4-quinonimines [1] and 4-aroyl-
(arylsulfonyl)oxyimino-2,5-cyclohexadienones [2].
Halogenation of 4-aroyl(arylsulfonyl)oxyimino-2,6-
(3,5)-dimethyl-2,5-cyclohexadienones was studied in
detail in [3]. Halogenation of 4-aroyloxyimino-2(3)-
methyl(2,5-dimethyl)-2,5-cyclohexadienones [4, 5],
4-aroyl(arylsulfonyl)oxyimino-2,3-dimethyl-2,5-cyclo-
hexadienones, 4-aroyl(arylsulfonyl)oxyimino-6-iso-
propyl-3-methyl-2,5-cyclohexadienones, and 4-aroyl-
(arylsulfonyl)oxyimino-2,6-di-tert-butyl-2,5-cyclo-
hexadienones [6] and chlorination of 4-aroyloxyimino-
2,6-diisopropyl-2,5-cyclohexadienones [5] were also
examined. These studies allowed us to reveal some
general relations holding in the halogenation processes
of 1,4-benzoquinone oxime esters [6].
inherent to halogenation of 1,4-benzoquinone oxime
esters I (X = ArCO, ArSO2).
4-Aroyl(arylsulfonyl)oxyimino-3-methyl-2,5-cyclo-
hexadienones I exist as E isomers where the aroyloxy
or arylsulfonyloxy group is located trans with respect
to the C2 C3 bond. The chlorination of compounds
I was performed using molecular chlorine in various
solvents: ethanol, dimethylformamide (DMF), and
DMF acetic acid mixtures. The bromination was
effected with bromine in acetic acid or chloroform.
The results of halogenation of compounds Ia Ii are
illustrated by Scheme 1.
In all cases, the first halogenation stage occurs at
the C5 C6 bond of the quinoid ring, i.e., at the double
bond containing no substituents. The products are the
corresponding 4-aroyl(arylsulfonyl)oxyimino-5,6-di-
halo-3-methyl-2-cyclohexenones II and III having
a semiquinoid structure (Scheme 1). By dehydrohalo-
genation of primary addition products II and III in
chloroform in the presence of triethylamine or in
glacial acetic acid containing sodium acetate we ob-
tained 4-aroyl(arylsulfonyl)oxyimino-6-halo-3-methyl-
2,5-cyclohexadienones IV and V.
4-Arylsulfonyloxyimino derivatives I (X = ArSO2)
were not studied in [4, 5], and only the first stage of
halogenation of 4-aroyloxyimino-3-methyl-2,5-cyclo-
hexadienones I (X = ArCO) was examined. The goal
of the present work was to obtain new differently
halogenated products and reveal general relations
____________
*
In keeping with our previous data [6], addition of
the second halogen molecule should occur at the
C2 C3 bond. However, the chlorination of IV gave
This study was financially supported by the ES INTAS
Program (grant no. 00157-99) and by the Ministry of Educa-
tion and Science of Ukraine.
1070-4280/02/3805-0683$27.00 2002 MAIK Nauka/Interperiodica

684
AVDEENKO et al.
Scheme 1.
II, IV, VI, VII, IX, X, Hlg = Cl; III, V, VIII, Hlg = Br; X = PhCO (a), 4-ClC6H4CO (b), 4-MeC6H4CO (c), 4-BrC6H4CO (d),
4-NO2C6H4CO (e), PhSO2 (f), 4-ClC6H4SO2 (g), 4-MeC6H4SO2 (h), 4-NO2C6H4SO2 (i).
semiquinoid structures, 4-aroyl(arylsulfonyl)oxy-
imino-5,6,6-trichloro-3-methyl-2-cyclohexenones VI
and 4-aroyl(arylsulfonyl)oxyimino-2,5,6-trichloro-5-
methyl-2-cyclohexenones VII, i.e., chlorine addition
involved preferentially the quinoid double bond
already containing chlorine atom. No products like VI
were formed in the bromination. By reaction of Ve
with bromine we obtained only 2,5,6-tribromo-5-
methyl-4-(4-nitrobenzoyloxyimino)-2-cyclohexenone
VIIIe. Presumably, the presence of a bulky bromine
atom in position 6 of Ve hinders attack of the C5 C6
bond by the second bromine molecule.
Taking into account that dehydrohalogenation of
semiquinoid structures derived from p-quinone oximes
is a regioselective process [6], no HCl elimination
from compounds VI was observed. By contrast, com-
pounds VII readily lose HCl molecule even under
the chlorination conditions to afford 4-aroyloxyimino-
2,6-dichloro-3-methyl-2,5-cyclohexadienones IXa and
IXe. The latter readily take up one more molecule
of chlorine, yielding 4-aroyloxyimino-2,5,6,6-tetra-
chloro-3-methyl-2-cyclohexenones Xa and Xe. Like
compounds VI, tetrachloro derivatives Xa and Xe
do not undergo dehydrochlorination.
The structure of products II X was proved by
1
elemental analyses (Table 1) and H (Table 2) and 13
C
1
NMR (for IIIg) spectra. In the H NMR spectra of
VIa VIg and VIi the 2-H signal appears as a quartet
at 6.34 6.49 ppm. The chemical shift of this proton
is consistent with its ortho position with respect to
the carbonyl group; the signal is split due to coupling
with the 3-CH3 protons. The singlet from 5-H is
located at 5.82 5.98 ppm, i.e., in the region typical
3
of Csp H protons in the ortho position with respect to
the C N O fragment. A singlet at 7.67 7.87 ppm
in the spectra of VIIa VIIc, VIIf, and VIIIe belongs
to the 3-H proton. The 6-H signal is observed at
4.52 4.99 ppm as a singlet. Compound IXa shows
1
in the H NMR spectrum a singlet at 8.01 ppm from
5-H, and the corresponding signal in the spectra of
Xa and Xe is located at 5.94 6.00 ppm. The 13C
NMR spectrum of 5,6-dibromo-4-(4-chlorophenylsul-
fonyloxyimino)-3-methyl-2-cyclohexenone (IIIg)
contains characteristic upfield signals from two
sp3-hybridized carbon atoms (CHBr) at
43.62
C
and 34.43 ppm.
Oxime esters Ig, IVc IVg, IVi, and Vf Vi are
characterized by IR absorption bands in the regions
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
685
Table 1. Melting points and elemental analyses of compounds Id, If, Ig Ii, IIa, IId IIg, IIi, IIIf IIIi, IVc IVg, IVi,
Va, Vf Vi, VIa, VId, VIg, VIi, XIIa, XIIb, XIII, XVIIIa, XXI, and XXII
Found, %
Calculated, %
Comp.
no.
mp, C (solvent)
Formula
Hlg
N
Hlg
N
Id
If
Ig
Ih
Ii
IIa
IId
IIe
IIf
172 (i-PrOH)
87 (i-PrOH)
146 (i-PrOH)
96 (i-PrOH)
138 (i-PrOH)
145 146 (AcOH)
105 (AcOH)
175 (AcOH)
84 (AcOH)
111 (AcOH)
131 133 (i-PrOH)
74 (i-PrOH)
145 (i-PrOH)
160 (i-PrOH)
169 (i-PrOH)
168 170 (AcOH)
190 (i-PrOH)
173 (AcOH)
115 116 (AcOH)
152 154 (AcOH)
168 (AcOH)
185 (AcOH)
134 (i-PrOH)
157 (AcOH)
134 (i-PrOH)
161 (AcOH)
147 148 (AcOH)
152 (AcOH)
25.01, 25.17
11.29, 11.36
4.39, 4.45
5.04, 5.16
4.40, 4.48
4.74, 4.80
8.69, 8.78
4.50, 4.58
3.57, 3.69
7.80, 7.81
4.00, 4.11
3.60, 3.76
7.01, 7.10
3.19, 3.28
2.99, 3.04
3.11, 3.17
5.80, 5.89
4.87, 4.96
3.85, 3.87
8.23, 8.26
4.50, 4.57
4.06, 4.13
7.74, 7.76
4.38, 4.49
3.92, 3.98
4.23, 4.24
3.77, 3.89
7.07, 7.20
4.06, 4.15
3.30, 3.39
3.37, 3.46
6.56, 6.67
8.52, 8.58
7.67, 7.76
9.07, 9.22
7.70, 7.84
7.52, 7.58
8.30, 8.39
C14H10BrNO3
C13H11NO4S
C13H10ClNO4S
C14H13NO4S
24.96
11.37
4.38
5.05
4.49
4.81
8.69
4.49
3.58
7.84
4.02
3.66
7.12
3.20
2.97
3.10
5.81
4.83
3.95
8.74
4.49
4.05
7.85
4.38
3.93
3.59
3.78
6.98
4.04
3.29
3.36
6.55
8.53
7.69
9.33
7.72
7.55
8.37
C13H10N2O6S
C14H11Cl2NO3
C14H10BrCl2NO3
C14H10Cl2N2O5
C13H11Cl2NO4S
C13H10Cl3NO4S
C13H10Cl2N2O6S
C13H11Br2NO4S
C13H10Br2ClNO4S
C14H13Br2NO4S
C13H10Br2N2O6S
C15H12ClNO3
C14H9BrClNO3
C14H9ClN2O5
C13H10ClNO4S
C13H9Cl2NO4S
C13H9ClN2O6S
C14H10BrNO3
C13H10BrNO4S
C13H9BrClNO4S
C14H12BrNO4S
C13H9BrN2O6S
C14H10Cl3NO3
C14H9BrCl3NO3
C13H9Cl4NO4S
C13H9Cl3N2O6S
C17H16N2O5
22.77, 22.86
38.60, 38.71
19.90, 19.99
20.39, 20.52
27.73, 27.76
18.00, 18.08
36.50, 36.56
39.98, 40.85
35.37, 35.48
33.09, 33.12
12.15, 12.18
32.37, 32.60
11.09, 11.27
11.41, 11.60
20.51, 20.72
9.97, 10.04
24.79, 24.98
22.36, 22.47
29.38, 29.40
21.54, 21.60
20.41, 20.52
30.55, 30.63
43.07, 43.40
34.08, 34.15
24.80, 24.90
22.72
38.56
19.85
20.36
27.80
18.03
36.56
41.41
35.42
33.15
12.24
32.53
11.06
11.37
20.48
9.94
24.96
22.43
29.53
21.58
19.92
30.69
43.78
34.00
24.87
IIg
IIi
IIIf
IIIg
IIIh
IIIi
IVc
IVd
IVe
IVf
IVg
IVi
Va
Vf
Vg
Vh
Vi
VIa
VId
VIg
VIi
XIIa
XIIb
XIII
XVIIIa
XXI
XXII
123 124 (AcOH)
160 162 (AcOH)
156 (i-PrOH)
130 (i-PrOH)
240 (i-PrOH)
158 (AcOH)
C16H16N2O6S
C15H12N2O5
C17H15ClN2O5
C15H12Cl2N2O5
C15H11ClN2O5
9.80, 9.98
19.02, 19.13
10.40, 10.51
9.77
19.10
10.59
143 (i-PrOH)
265 (AcOH)
1
1665 1650, 1615 1580, and 1585 1580 cm , which
belong to the quinoid C O, C C, and C N groups,
respectively. In the IR spectra of semiquinoid com-
pounds the carbonyl absorption band appears at higher
frequencies. The bands at 1710 1680, 1625 1610, and
We assumed in [5] trans-diaxial orientation of the
chlorine atoms attached to the sp3-hybridized carbon
atoms in cyclohexene structures obtained by chlorina-
tion of p-quinone oxime esters. This assumption was
confirmed by the results of X-ray analysis of com-
pound VIa (Fig. 1). The cyclohexene fragment adopts
a distorted semichair conformation. The C5 and C6
atoms deviate from the mean-square plane formed
1
1600 1580 cm in the spectra of IIb, IId IIg, IIi,
Ve Vh, and VId correspond to the C O, C C, and
C N bonds of the cyclohexenone fragment.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

686
AVDEENKO et al.
Table 2. 1H NMR spectra of compounds IId, IIi, IIIf, IIIg, IIIh, IVd, IVf, IVi, Va, Vf Vh, VIa VIg, VIi, VIIa VIIc,
VIIf, IXa, Xa, Xe, XIV, XV, XVIa, XVIb, XVIIa, XVIIb, XVIIIa, XIXa, XXa, and XXI XXIV
Chemical shift , ppm
Comp.
no.
JMe, H,
Hz
2-H, 2-Me, 2-Pr-i
3-H, 3-Me
5-H, 5-Me
6-H, 6-Me, 6-Pr-i
protons in X
IId
IIi
IIIf
IIIg
IIIh
6.36 q (1H)
6.29 q (1H)
6.19 q (1H)
6.22 q (1H)
6.19 q (1H)
2.37 d (3H)
2.11 d (3H)
2.15 d (3H)
2.12 d (3H)
2.11 d (3H)
5.67 d (1H)
5.53 d (1H)
5.61 d (1H)
5.60 d (1H)
5.60 d (1H)
4.44 d.d (1H)
4.37 d.d (1H)
4.52 d.d (1H)
4.54 d.d (1H)
4.53 d.d (1H)
7.69 8.00 d.d (4H)
8.20 8.49 d.d (4H)
7.50 8.03 m (5H)
7.54 7.97 d.d (4H)
7.35 7.91 d.d (4H),
2.47 s (3H, Me)
7.68 8.02 d.d (4H)
7.58 8.06 m (5H)
8.20 8.49 d.d (4H)
7.54 8.16 m (5H)
7.50 8.08 m (5H)
7.55 8.01 d.d (4H)
7.36 7.93 d.d (4H),
2.48 s (3H, Me)
7.55 8.15 m (5H)
7.53 8.07 d.d (4H)
7.33 8.01 d.d (4H),
2.48 s (3H, Me)
7.69 8.00 d.d (4H)
8.29 8.45 d.d (4H)
7.56 8.06 m (5H)
7.56 8.00 d.d (4H)
8.21 8.48 d.d (4H)
7.56 8.15 m (5H)
7.53 8.07 d.d (4H)
7.33 8.01 d.d (4H),
2.47 s (3H, Me)
7.56 8.06 m (5H)
8.28 8.43 d.d (4H)
7.54 8.15 m (5H)
7.75 8.14 m (5H)
8.29 8.45 d.d (4H)
1.2
1.0
1.3
1.4
1.3
IVd
IVf
IVi
Va
Vf
6.59 q (1H)
6.47 q (1H)
6.50 q (1H)
7.32 q (1H)
6.49 q (1H)
6.50 q (1H)
6.48 q (1H)
2.39 d (3H)
2.15 d (3H)
2.15 d (3H)
2.17 d (3H)
2.13 d (3H)
2.14 d (3H)
2.14 d (3H)
7.91 s (1H)
7.77 s (1H)
7.76 s (1H)
8.24 s (1H)
8.04 s (1H)
8.03 s (1H)
8.04 s (1H)
1.4
1.2
1.3
1.4
Vg
Vh
VIa
VIb
VIc
6.46 q (1H)
6.46 q (1H)
6.45 q (1H)
2.39 d (3H)
2.36 d (3H)
2.39 d (3H)
5.98 s (1H)
5.91 s (1H)
5.97 s (1H)
1.2
VId
VIe
VIf
VIg
VIi
VIIa
VIIb
VIIc
6.46 q (1H)
6.49 q (1H)
6.35 q (1H)
6.37 q (1H)
6.39 q (1H)
2.38 d (3H)
2.39 d (3H)
2.11 d (3H)
2.12 d (3H)
2.12 d (3H)
7.87 s (1H)
7.80 s (1H)
7.87 s (1H)
5.93 s (1H)
5.96 s (1H)
5.82 s (1H)
5.82 s (1H)
5.83 s (1H)
2.39 s (3H)
2.15 s (3H)
2.21 s (3H)
1.3
1.2
0.9
1.2
1.5
4.64 s (1H)
4.61 s (1H)
4.64 s (1H)
VIIf
VIIIe
IXa
Xa
Xe
XIV
XV
7.67 s (1H)
8.08 s (1H)
2.40 s (3H)
2.55 s (3H)
2.55 s (3H)
2.10 d (3H)
7.29 q (1H)
7.34 br.s (1H)
1.93 s (3H)
2.40 s (3H)
8.01 s (1H)
6.00 s (1H)
5.94 s (1H)
5.52 s (1H)
1.93 s (3H)
2.18 s (3H)
4.52 s (1H)
4.99 s (1H)
6.28 q (1H)
2.08 d (3H)
3.03 3.14 m
(1H, CH),
1.84 s (3H)
4.38 s (1H)
4.48 s (3H)
7.78 8.90 m (4H)
7.78 8.90 m (4H)
8.27 8.42 d.d (4H)
1.2
1.8
XVIa
1.23 1.27 d.d
(6H, Me)
XVIb
2.99 3.10 m
(1H, CH),
7.16 s (1H)
1.96 s (3H)
4.39 s (1H)
7.80 8.90 m (4H)
1.17 1.25 d.d
(6H, Me)
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
687
Table 2. (Contd.)
Chemical shift , ppm
Comp.
no.
2-H, 2-Me, 2-Pr-i
3-H, 3-Me
2.33 d (3H)
2.08 d (3H)
2.52 s (3H)
2.48 s (3H)
5-H, 5-Me
5.67 s (1H)
5.49 s (1H)
6-H, 6-Me, 6-Pr-i
protons in X
XVIIa
XVIIb
XVIIIa
XIXa
6.34 q (1H)
6.24 q (1H)
2.71 2.76 m (1H, CH),
1.12 1.20 d.d (6H, Me)
2.59 2.69 m (1H, CH),
1.05 1.15 d.d (6H, Me)
8.27 8.42 d.d (4H)
7.80 8.90 m (4H)
8.29 8.44 d.d (4H)
8.25 8.43 d.d (4H)
8.25 8.43 d.d (4H)
7.52 br.s (1H) 3.14 3.24 m (1H, CH),
1.21 1.23 d.d (6H, Me)
5.69 s (1H)
2.74 2.84 m (1H, CH),
1.26 1.28 d.d (6H, Me)
XXa
3.14 3.20 m (1H, CH), 7.38 s (1H)
1.14 1.16 d.d (6H, Me)
2.39 br.s (3H)
XXI
2.12 s (3H)
2.14 s (3H)
2.37 s (3H)
2.38 s (3H)
7.81 s (1H)
2.37 s (3H)
5.68 d (1H)
7.89 br.s (1H)
2.23 s (3H)
5.94 s (1H)
4.52 d (3H)
2.02 s (3H)
8.29 8.41 d.d (4H)
8.30 8.42 d.d (4H)
8.29 8.45 d.d (4H)
8.29 8.45 d.d (4H)
XXII
XXIII
XXIV
2.18 s (3H)
by the other cyclohexene ring atoms by 0.23 and
of 15.4(4) with respect to the N1 O2 bond (torsion
0.43 , respectively. The Cl1 and Cl3 atoms occupy
angle N1O2C8O3). Molecules VIa in crystal have E
configuration, i.e., the OCOPh group is located trans
with respect to the cyclohexene double bond.
trans-diaxial positions, and the Cl2 atom is equatorial:
the torsion angles C3C4C5Cl1, C2C1C6Cl3, and
C2C1C6Cl2 are 86.1(3), 73.3(3), and 167.5(2) ,
respectively. The benzoyl C O group is nearly anti-
On the whole, molecule VIa is considerably
strained. This follows from the shortened intramole-
cular contacts Cl3 C3 3.44 (the sum of the corre-
sponding van der Waals radii is 3.61 [7]), H5 O2
periplanar relative to the N1 C4 bond [torsion angle
C8O2N1C4 170.3(2) ] and is turned through an angle
Fig. 1. Structure of the molecule of 4-benzoyloxyimino-5,6,6-trichloro-3-methyl-2-cyclohexenone (VIa) according to the X-ray
diffraction data.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

688
AVDEENKO et al.
2.33
(2.45 ), and H14 O2 2.39
(2.45
[7]).
(XVIII), which is formed by dehydrochlorination of
As a result, the bonds C1 C6 1.565(4)
(average
XVIa, also results in halogen addition at both C2 C3
and C5 C6 bonds, yielding products XIX and XX
(Scheme 3).
value 1.506 [8]), C2 C3 1.364(4) (1.326 [8]),
C3 C4 1.499 (4)
1.517(4) (1.487
(1.478
[8]) are elongated.
[8]), and C8 C9
Treatment of 2,3-dimethyl derivative XIII with
chlorine gave product XXI via halogen addition at
the C5 C6 bond. Its dehydrochlorination afforded
6-chloro-2,3-dimethyl-4-(4-nitrobenzoyloxyimino)-
2,5-cyclohexadienone (XXII). The chlorination of
XXII resulted in formation of two compounds, 2,5,6-
trichloro-5,6-dimethyl-4-(4-nitrobenzoyloxyimino)-
2-cyclohexenone (XXIII) and 5,6,6-trichloro-2,3-di-
methyl-4-(4-nitrobenzoyloxyimino)-2-cyclohexenone
(XXIV). The latter is the product of chlorine addition
at the C C bond already containing chlorine atom
(Scheme 4).
While studying the chlorination of 4-aroyl(arylsul-
fonyl)oxyimino-2,5-dialkyl-2,5-cyclohexadienones
[4 6], we isolated products of halogen addition at only
one of the two quinoid C C bonds. The bromination
gave addition products at both C C bonds [4]. Taking
these data into account, we performed a more detailed
study of the chlorination of 2,5-dimethyl-4-(3-nitro-
phenylsulfonylimino)-2,5-cyclohexadienone (XI),*
4-aroyl(arylsulfonyl)oxyimino-6-isopropyl-3-methyl-
2,5-cyclohexadienones XIIa and XIIb, and 2,3-di-
methyl-4-(4-nitrobenzoyloxyimino)-2,5-cyclohexadi-
enone (XIII). By chlorination of compounds XI
(Scheme 2) and XII (Scheme 3) we obtained chlorine
addition products at either of the quinoid C C bonds.
The chlorination of 2-chloro-6-isopropyl-3-methyl-
4-(4-nitrobenzoyloxyimino)-2,5-cyclohexadienone
The structure of compounds XII XXIV was con-
firmed by the data of elemental analysis (Table 1) and
1H NMR spectroscopy (Table 2). In order to prove
the structure of XXI, specifically the trans-diaxial
3
orientation of chlorine atoms at the Csp carbon atoms,
Scheme 2.
X = 3-NO2C6H4CO.
Scheme 3.
XIIa, XVIa, XVIIa, XVIII XX, X = 4-NO2C6H4CO; XIIb, XVIb, XVIIb, X = 3-NO2C6H4SO2.
____________
*
As in Russian original. Publisher.
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HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
689
Scheme 4.
X = 4-NO2C6H4CO.
we performed X-ray analysis of its structural analog,
previously synthesized 4-benzoyloxyimino-5,6-di-
chloro-2,3-dimethyl-2-cyclohexenone (XXV). The
O1C1C2C3C4N fragment in molecule XXV is planar,
the average deviation of atoms from the mean-square
plane is 0.033 . The C5, C6 and Cl1, Cl2 atoms are
disordered by two positions A and B with equal
populations (Fig. 2), presumably due to existence of
two conformers. The deviations of C5 and C6 in con-
former A from the mean-square plane formed by the
O1, C1, C2, C3, C4, and N atoms are, respectively,
0.51 and 0.27 . The corresponding deviations for
The molecule of XXV has E configuration with the
OCOPh group located trans with respect to the double
C C bond of the cyclohexene ring.
EXPERIMENTAL
The IR spectra were recorded on a UR-20 spec-
1
trometer in KBr. The H NMR spectra were measured
on a Varian VXR-300 instrument at 300 MHz relative
to TMS as internal reference; CDCl3 was used as
solvent. The 13C NMR spectrum of compound IIIg
was obtained on the same instrument at 75.4 MHz in
CDCl3 using TMS as internal reference.
X-Ray diffraction data for a single crystal of com-
pound VIa (monoclinic) were acquired on a Siemens
conformer B are 0.05 and 0.48 . The chlorine
atoms in both conformers occupy trans-diaxial posi-
tions, and the hydrogen atoms are nearly equatorial.
Fig. 2. Structure of the molecule of 4-benzoyloxyimino-5,6-dichloro-2,3-dimethyl-2-cyclohexenone (XXV) according to the
X-ray diffraction data.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

690
AVDEENKO et al.
P3/PC four-circle automatic diffractometer ( MoK
irradiation, graphite monochromator, 2 / -scanning,
(93%); IVb (51%), VIb (49%); in DMF: VIa (38%),
IXa (12%), Xa (50%); VIe (50%), Xe (50%).
2
50 ). The structure was solved by the direct
Chlorination of 4-aroyl(arylsulfonyl)oxyimino-
2-chloro-5-methyl-2,5-cyclohexadienones IVa IVg
and IVi. Gaseous chlorine was passed at a rate of
15 20 ml/min through a solution of 0.4 g of com-
pound IVa IVg or IVi in 3 ml of EtOH, DMF, or
DMF AcOH (1:1 or 5:1), heated to 70 C, until
saturation. The mixture was diluted with water, and
the precipitate was filtered off and recrystallized.
The following products were obtained: in EtOH: VIa
(98%); VIf (93.2%), VIIf (6.8%); VIg (98%); VIi
(97%); in DMF: VIb (54%), VIIb (46%); VIc (26%),
VIIc (74%); in DMF AcOH (1:1): VIa (15%), Xa
(85%); VId (97%); in DMF AcOH (5:1): VIa (79%),
VIIa (21%); VIe (50%), Xe (50%).
Chlorination of oxime esters XI, XIIa, XIIb,
XIII, XVIIIa, and XXII. Gaseous chlorine was
passed at a rate of 15 20 ml/min through a solution
of 0.3 g of compound XI, XIIa, XIIb, XIII, XVIIIa,
or XXII in 3 ml of DMF or DMF AcOH (1:1, 3:1,
or 5:1), heated to 70 80 C, until saturation. The
mixture was diluted with water, and the precipitate
was filtered off and recrystallized from acetic acid.
The following compounds were obtained: in DMF
from XI: XIV (67%), XV (33%); in DMF AcOH
(1:1) from XIIa: XVIa (67%), XVIIa (33%); from
XIII: XXI (98%); in DMF AcOH (3:1) from XIIb:
XVIb (64%), XVIIb (36%); from XXII: XXIII
(64%), XXIV (36%); in DMF AcOH (5:1) from
XVIIIa: XIXa (94%), XXa (6%).
memthaxod using SHELX-97 software package [9]. The
positions of hydrogen atoms were determined from
the difference synthesis of electron density and were
refined in isotropic approximation. The structure was
refined with respect to F2 by the full-matrix least-
squares procedure in anisotropic approximation for
non-hydrogen atoms.
X-Ray diffraction study of a single crystal of XXV
(monoclinic) was performed on an Enraf Nonius
CAD-4 four-circle automatic diffractometer ( CuK
irradiation, graphite monochromator, scan rates ratio
/2 1.2). The structure was solved by the direct
method and was refined by the least-squares procedure
in full-matrix anisotropic approximation using
SHELXS-86 and SHELXL-93 software packages
[10, 11]. All hydrogen atoms were visualized by the
difference synthesis of electron density and were
refined in isotropic approximation.
The reaction mixtures were analyzed by TLC on
Silufol UV-254 plates using benzene ethyl acetate
(10:1) as eluent; development with UV light.
Alkyl-substituted 4-aroyl(arylsulfonyl)oxyimino-
2,5-cyclohexadienones Ia Ii, XI, XIIa, XIIb, and
XIII were synthesized by acylation of the correspond-
ing p-benzoquinone oximes with aroyl or arenesul-
fonyl chlorides in diethyl ether in the presence of
triethylamine [12]. The newly synthesized compounds
are characterized in Table 1.
Chlorination of 4-aroyl(arylsulfonyl)oxyimino-
3-methyl-2,5-cyclohexadienones Ia Ig and Ii.
a. Gaseous chlorine was passed at 40 50 C at a rate
of 15 20 ml/min through a solution of 0.3 g of oxime
ester Ib Ig or Ii in 3 ml of EtOH or a DMF AcOH
mixture (1:1 or 5:1) until saturation. When the reac-
tion was performed in EtOH, the product precipitated
in several hours and was filtered off. The mixtures
obtained in DMF AcOH were diluted with water, and
the precipitate was filtered off. The products were
purified by recrystallization (Table 1). The following
compounds were obtained: in EtOH: IIb (10%; here-
Bromination of oxime esters If Ii and Ve.
a. A solution of 0.2 ml of bromine in 2 ml of CHCl3
or AcOH was added dropwise under vigorous stirring
to a solution of 0.4 g of compound If Ii in 2 ml of
the same solvent, maintaining the temperature in the
range from 20 to 40 C. After 24 h, the precipitate was
filtered off and recrystallized. The following products
were obtained: in CHCl3: IIf (91%); in AcOH: IIIg
(89%); IIIh (92%); IIIi (94%).
b. A solution of 0.3 ml of bromine in 1 ml of
CHCl3 was added dropwise under vigorous stirring to
a solution of 0.2 g of compound Ve in 2 ml of CHCl3,
maintaining the temperature at 20 C. After 24 h, the
precipitate was filtered off and recrystallized from
acetic acid. A mixture of compounds Ve and VIIIe
was thus obtained.
1
inafter, the yield was determined from the H NMR
data), IVb (29%), VIb (62%); IIc (85%); IVf (95%);
in DMF AcOH (1:1): IId (92%); IIe (93%); in
DMF AcOH (5:1): IIf (80%); IIg (98%), IIi (83%).
b. A solution of 0.5 g of oxime ester Ia, Ib, or Ie
in 3 ml of EtOH or DMF was saturated with chlorine
at a flow rate of 15 20 ml/min (50 60 C). The prod-
ucts were isolated as described above in a. The fol-
lowing compounds were obtained: in EtOH: IIa
13C NMR spectrum of 5,6-dibromo-4-(4-chloro-
phenylsulfonyloxyimino)-3-methyl-2-cyclohexenone
(IIIg), C, ppm: 187.03 (C O), 157.34 (C N),
145.15 (C4 in ArSO2), 142.09 (C3), 133.35 (C1 in
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 5 2002

HALOGENATION OF N-SUBSTITUTED p-QUINONIMINES
691
ArSO2), 130.81 (C3 in ArSO2), 129.97 (C2 in ArSO2),
129.59 (C2), 43.62 (C5), 34.43 (C6), 18.49 (Me).
2. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Zh. Org. Khim., 1993, vol. 29, no. 7,
pp. 1402 1411; Avdeenko, A.P. and Glinya-
naya, N.M., Russ. J. Org. Chem., 1995, vol. 31,
no. 11, pp. 1507 1513.
Dehydrohalogenation of 4-aroyl(arylsulfonyl)-
oxyimino-5,6-dihalo-3-methyl-2-cyclohexenones
IId, IIi, IIIa, and IIIe IIIi. Triethylamine, 0.1
0.15 ml, was added to a solution of 1 mmol of com-
pound IId, IIIa, or IIIe IIIi in a minimal amount
of chloroform, and the solution was heated until it
turned yellow. The mixture was cooled, and the pre-
cipitate was filtered off, washed with a small amount
of acetic acid, and recrystallized from acetic acid.
3. 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.
4. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Russ. J. Org. Chem., 1995, vol. 31, no. 10,
pp. 1380 1385.
5. Avdeenko, A.P., Glinyanaya, N.M., and Pirozhen-
ko, V.V., Russ. J. Org. Chem., 1996, vol. 32, no. 1,
pp. 85 89.
Dehydrohalogenation of compound IIi was carried
out in glacial acetic acid in the presence of an equi-
molar amount of sodium acetate. The mixture was
heated to the boiling point and cooled, and the precip-
itate was filtered off, washed with acetic acid, and
recrystallized from acetic acid.
6. Avdeenko, A.P., Zhukova, S.A., and Konovalo-
va, S.A., Russ. J. Org. Chem., 2001, vol. 37, no. 3,
pp. 382 387.
7. Zefirov, Yu.V. and Zorkii, P.M., Usp. Khim., 1989,
vol. 58, no. 5, pp. 713 716.
REFERENCES
8. Burgi, H.-B. and Dunitz, J.D., Structure Correlation,
1. Avdeenko, A.P., Velichko, N.V., Romanenko, E.A.,
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1991, vol. 27, no. 11, pp. 2350 2361; Avdeenko, A.P.,
Velichko, N.V., Romanenko, E.A., and Pirozhen-
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9. Sheldrick, G.M., et al., SHELX-97. PC Version.
A System of Computer Programs for the Crystal
Structure Solution and Refinement. Rev. 2. 1998.
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the Solution of Crystal Structures, Gottingen: Univ.
of Gottingen, 1986.
11. Sheldrick, G.M., et al., SHELXL-93. Program for
the Refinement of Crystal Structures, Gottingen:
Univ. of Gottingen, 1993.
12. Titov, E.A. and Burmistrov, S.I., Ukr. Khim. Zh.,
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