Reaction of polyfluorinated cyclohexa-2,4-dienones with aryl nitrile oxides

Article abstract of DOI:10.1134/S1070428013080204

Reaction of 1,3-dipolar cycloaddition of 6-chloropentafluorocyclohexa-2,4- dienone, 6-chloro-3-(pentafluorophenoxy)tetrafluorocyclohexa-2,4-dienone, and perfluoro-6-phenoxycyclohexa-2,4-dienone with aryl nitrile oxides proceeds highly stereoselectively at

Full text of DOI:10.1134/S1070428013080204

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2013, Vol. 49, No. 8, pp. 1215−1220. © Pleiades Publishing, Ltd., 2013.
Original English Text © V.N. Kovtonyuk, Yu.V. Gatilov, 2013, published in Zhurnal Organicheskoi Khimii, 2013, Vol. 49, No. 8, pp. 1230−1235.
Reaction of Polyfluorinated Cyclohexa-2,4-dienones
with Aryl Nitrile Oxides
V. N. Kovtonyuk and Yu. V. Gatilov
Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences,
Novosibirsk, 630090 Russia
e-mail: kovtonuk@nioch.nsc.ru
Received February 2, 2013
Abstract—Reaction of 1,3-dipolar cycloaddition of 6-chloropentafluorocyclohexa-2,4-dienone, 6-chloro-3-
(
pentafluorophenoxy)tetrafluorocyclohexa-2,4-dienone, and perfluoro-6-phenoxycyclohexa-2,4-dienone with
aryl nitrile oxides proceeds highly stereoselectively at the с С=O group of the dienone providing in a high yield
mixtures of diastereomeric fluorine-containing 3-aryl-1,4-dioxa-2-azaspiro[4,5]deca-2,6,8-trienes. The reaction of
the latter with sodium pentafluorophenolate proceeds along the type of allyl substitution affording polyfluorinated
3
-aryl-8-phenoxy-1,4-dioxa-2-azaspiro[4,5]deca-2,6,9-trienes.
DOI: 10.1134/S1070428013080204
Polyfluorinated cyclohexadienones possess high
and versatile reactivity, therefore they are suitable for
the selective synthesis of organofluorine compounds
of diverse classes [1]. We showed formerly that the
containing toluylenes and spiro[indazol-7,2’-oxiranes]
alongside with phenylbicyclo[4.1.0]hept-4-en-2-ones [4].
Here we report on the results of the study of 1,3-dipolar
cycloaddition reactions between polyfluorinated
cyclohexa-2,4-dienones and aryl nitrile oxides.
1
,3-dipolar cycloaddition of diazomethane and nitrile
oxides with polyfluorocyclohexa-2,5-dienones proceeded
exclusively at the carbonyl group providing in good yields
mixtures of diastereomeric cyclohexadienespirooxiranes
and cyclohexadienespirodioxazoles respectively [2, 3].
The direction of the reaction between polyfluorinated
cyclohexa-2,4-dienones and diazo compounds depends
both on the structure of the reagent and on the polar-
ity of the environment [4]. For instance, the reaction
of pentafluoro-6-chlorocyclohexa-2,4-dienone with
diazomethane occurs at the С=O and С=С bonds of
the dienone giving a mixture of two isomeric fluorine-
containing derivatives of spiro[indazol-7,2’-oxirane].
The reaction of polyfluorinated cyclohexa-2,4-dienones
with phenyldiazomethane in acetonitrile proceeds
mainly at the С=С bond of the cyclohexa-2,4-dienone
affording cyclopropanation products, polyfluorinated
phenylbicyclo[4.1.0]hept-4-en-2-ones. In pentane the pri-
mary reaction of the phenyldiazomethane occurs mainly
at the carbonyl group of the cyclohexa-2,4-dienone
leading to the formation of a complex products mixture
The reaction of 6-chloropentafluorocyclohexa-
,4-dienone (I) and 6-chloro-3-(pentafluorophenoxy)
tetrafluorocyclohexa-2,4-dienone (II) with aryl nitrile
oxides leads to the formation in a good yield of a mixture
of diastereomeric fluorine-containing 3-aryl-1,4-dioxa-
2
2
(
-azaspiro[4,5]deca-2,6,8-trienes IIIа, IIIb–VIIа, VIIb
Scheme 1).
The composition and structure of compounds III–VII
1
19
were established basing on Н and F NMR spectra of
the diastereomers mixtures and on the elemental analyses.
The observed regularities in the fine structure of the
19
signals in the F NMR spectra of compounds III–VII are
similar to those in the spectra of the initial polyfluorinated
cyclohexa-2,4-dienones [5] and of fluorine-containing
dihydro-1,3-benzoxazol-2(3Н)-ones [2] having a
fluorosubstituted cyclohexa-1,3-diene fragment.
Isomer Va was isolated in a pure state, and its structure
was established by X-ray analysis (see the figure).
The dioxazole ring is flat, the bond lengths in it
1
215

1216
KOVTONYUK, GATILOV
Scheme 1.
Ar
N
Ar
N
O
F
F
O
O
O
O
F
F
F
F
F
Cl ArCNO
Cl
Cl
+
Y
F
Y
F
Y
F
F
F
I Y = F
I, II
Ar = Ph
IIIa 85 : 15 IIIb
Molecular structure of 3-(4-bromophenyl)-6,7,8,9,10-
pentafluoro-10-chloro-1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-
triene (Va) established by X-ray analysis.
Ar = 4-CH OC H IVa
84 : 16 IVb
86 : 14 VIb
VIa 86 : 14 VIb
3
6 4
Ar = 4-BrC H
Va
6
4
Ar = 3-O NC H
6 4
2
II Y = OC F Ar = Ph
= Ph
VIIa 84 : 16 VIIb
A
6
r
5
reacts with aryl nitrile oxide exclusively at the carbonyl
group even at long keeping with an excess of relatively
stable 4-bromo- and 3-nitrobenzonitrile oxides (Scheme
are close in values to the analogous bonds in 8-penta-
fluorophenoxy-3-phenyl-6,7,8,9,10-pentafluoro-1,4-
dioxa-2-azaspiro[4.5]deca-2,6,9-triene (VIII) [3] and
in 7-tert-butyl-3,3’-bis(2,6-dichlorophenyl)spiro-{1,2-
benzisoxazole-5(4H),5'-[1,4,2]dioxazol}-4-one [6]. The
angle between the planes of dioxazole and bromophenyl
equals 7.9(2)°. The hexadiene ring has the conformation
1
1
2
). The ratio of the formed diastereomers shows that the
,3-dipolar cycloaddition of polyfluorinated cyclohexa-
,4-dienones with aryl nitrile oxides occurs with relatively
high stereoselectivity. This stereoselectivity is apparently
due to the lesser shielding of the С=O group by the fluo-
rine atom than by the considerably large chlorine atom
3
located at the contiguous sp -hybridized carbon of the
5
,6
of a distorted bath with deviation of atoms С from the
polyfluorinated cyclohexa-2,4-dienone. This should result
in the prevailing attack from the side of the fluorine atom
leading respectively to the formation of diastereomers
IIIa–VIIa as is proved actually by the structure of
compound Vа established by X-ray analysis. It is ex-
pectable that at the replacement of the chlorine atom for
a more bulky pentafluorophenoxy group in the geminal
node of the polyfluorinated cyclohexa-2,4-dienone the se-
lectivity of the 1,3-dipolar cycloaddition with aryl nitrile
oxides should grow even more. We studied the reaction
with benzonitrile oxide of a mixture (33:67) of perfluoro-
4-phenoxycyclohexa-2,5-dienone (X) and perfluoro-6-
phenoxycyclohexa-2,4-dienone (XI). The analysis of the
reaction mixture by F NMRspectroscopy showed that
the 1,3-dipolar cycloaddition of cyclohexadienone XI oc-
curred with very high stereoselectivity with the formation
of diastereomers XIIa, XIIb (~97 : 3) (Scheme 2). The
formation of diastereomer XIIb was presumed basing
on the presence in the F NMR spectrum of the product
mixture of weak signals at 5.1, 7.2, 9.7, and 23.3 ppm
that we assigned to the signals of atoms F , F , F , and
7
8 9 10
plane С С С С by 0.642(5) and 0.247(5) Å respectively.
1
1
In the crystal shortened intermolecular contacts Br …Br
.5751(6) and F …F 2.755(3) Å were observed, and
also a weak hydrogen bond C –H …N (H…N 2.59 Å,
C–H…N 148°).
3
4
3
1
2
12
2
The reaction of dienone I with preliminary generated
aryl nitrile oxide proceeds easily and in a good yield. The
reaction with aryl nitrile oxides generated in situ [3] is
accompanied with the formation of a significant amount
of side products, presumably due to the high reactivity
of dienone I with respect to nucleophilic substitution [7].
As nucleophile the pentafluorophenol may serve which is
present as impurity in initial dienone I; this results in the
formation of dienone II. Thus, in the reaction of dienone
I with 4-methoxybenzonitrile oxide dioxazoles IVа, IVb
were isolated with the admixtures of compounds whose
1
9
1
9
structures were suggested basing on F NMR spectrum
to be 3-(4-methoxyphenyl)-7-pentafluorophenoxy-
1
9
6,8,9,10-tetrafluoro-10-chloro-1,4-dioxa-2-azaspiro-[4.5]
9
8
7
deca-2,6,8-trienes (IXа, IXb), products of the reaction of
dienone II with methoxybenzonitrile oxide.
1
0
F
respectively; the signals possessed a fine structure
close to that observed in the respective signals of fluorine
atoms in diastereomer XIIа.
1
,2-Benzoquinones depending on the presence in the
ring of bulky substituents are known to react with nitrile
oxides either only at the carbonyl group, or both at the
С=С and С=O bonds [6, 8]. Polyfluorinated dienone I
At the same time the ratio of diastereomers VIIIa,
VIIIb (54 : 46) formed in the reaction of benzonitrile
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 8 2013

REACTION OF POLYFLUORINATED CYCLOHEXA-2,4-DIENONES
1217
Scheme 2.
Ph
Ph
Ph
Ph
N
O
N
O
N
O
N
O
O
O
O
O
O
O
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
OC6F
5
PhCNO
OC6F5
OC F
OC F
6
6 5
+
+
+
+
5
F
F
F
F
F
F
F
F OC6F
5
F
F OC6F5
F OC6F5
F
F
X
XI
VIIIa 54 : 46 VIIIb
XIIa
~97 : 3
XIIb
oxide with cyclohexa-2,5-dienone X where the
pentafluorophenoxy group in the geminal node cannot
effect the sterical hindrance to the reaction at the carbonyl
group demonstrates the virtually total absence of the
stereoselectivity [3]. Note also that the Diels–Alder
reactions of polyfluorinated cyclohexa-2,4-dienones
with styrenes and acetylene derivatives are also highly
stereoselective due to the steric effect of the substituents
in the geminal node of the dienone [9].
substitution, but here the leaving group is either the
pentafluorophenoxy group or the fluorine atom giving
compounds VIII, XV (Scheme 3). We have obtained
compounds VIII, XIII, XIV earlier by the reaction of
cyclohexa-2,5-dienone X with the corresponding aryl
nitrile oxides [3].
EXPERIMENTAL
The analytic and spectral measurements were carried
out in the Chemical Service Center for collective use of
the Siberian Division, Russian Academy of Sciences.
The perfluorocyclohexa-1,3-diene is known to react
with nucleophilic reagents at the position 2 with the
formation of the corresponding product of fluorine
substitution at the double bond [10, 11]. The formation
in a small yield of the products of allyl substitution of
fluorine atom was also observed [10]. We studied the
reaction of compounds Vа, Vb (96:4), VIа, VIb (86 :
1
19
H and F NMR spectra were registered on a spec-
trometer Bruker AV300 at operating frequencies 300.13
and 282.36 MHz respectively from solutions in CCl con-
4
6
taining ~5% of DMSO-d . Internal references DMSO-d6
(
2.54 ppm from TMS) and С F . The reaction progress
1
4), and XIIа, XIIb with sodium pentafluorophenolate.
6 6
was monitored by TLC on Merck 60 F254 plates. The
column chromatography was carried out on silica gel
Merck (0.063–0.200 mm).
The reaction of compounds Vа, Vb and VIа, VIb
with sodium pentafluorophenolate proceeds as an allyl
substitution of the chlorine atom affording in good yield
the corresponding diastereomeric fluorine-containing
The composition of compounds Va, XV was derived
from the high resolution mass spectra measured on an
instrument DFS Termo Scientific (EI, 70 eV).
3
-aryl-8-pentafluorophenoxy-1,4-dioxa-2-azaspiro[4,5]
deca-2,6,9-trienes XIIIа, XIIIb and XIVа, XIVb
(
Scheme 3).
X-Ray experiment with compound Vа was carried
out on a diffractometer Bruker Kappa Apex (MoKα-
radiation, graphite monochromator, CCD detector, φ,ω-
The reaction of compound XII with sodium
pentafluorophenolate also occurs by the type of allyl
Scheme 3.
Ar
Ar
Ph
Ph
N
N
N
N
O
O
O
O
O
O
O
O
F
F
F
F
F
F
F
F
F
OC6F5
F
C F ONa (X = Cl)
C
F
ONa (X = OC
F
5,
Ar = Ph)
6
5
X
6
5
6
+
CH CN
CH CN
3
3
F
F
F
F
F
F OC6F5
F
F OC6F5
F OC6F5
XIII, XIV
V, VI, XII
VIII
XV
Ar = 4-BrC H (XIII), 3-NO C H (XIV).
6
4
2
6
4
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 8 2013

1218
KOVTONYUK, GATILOV
8
9
scanning). Crystallographic parameters of compound
Va: triclinic crystal system, a 5.6838(4), b 11.1270(9), c
6.6 d.d.t (1F, F , J 11, 6 , ~3 Hz), 6.9 d.d.t (1F, F , J 20,
7
17, ~3 Hz), 10.1 d.m (1F, F , J 6 Hz), 24.5 d.d.d.d (1F,
F , J 20, 11, 4, ~2 Hz). F NMR spectrum, δ, ppm,
1
0
19
1
1.4009(9) Å; α 82.780(4), β 81.209(4), γ 86.101(3)°; V
3
6
7
06.04(9) Å , space group P-1, C H BrClF NO , Z 2,
diastereomer IIIb: 7.2 d.d.t (1F, F , J 17, 6, ~3 Hz),
1
3
4
5
2
–3
–1
8
9
dcalc 1.959 g cm , μ 3.165 mm , 2θ <55.2°. The inten-
sities of 16219 reflections were measured, among them
7.4 d.d.t (1F, F , J 12, 6, ~3 Hz), 8.5 d.d.t (1F, F , J 23,
7
10
17, ~3 Hz), 9.7 d.m (1F, F , J 6 Hz), 30.9 d.d.d.d (1F, F ,
J 23, 12, 6, ~3 Hz). Found, %: С 46.26; Н 1.43; Cl 10.44;
F 28.30; N 3.58. M 339. С H ClF NO . Calculated, %:
3
249 independent reflections. The results of refinement
are as follows: wR 0.1273, S 1.058, R 0.0377 for 2596
2
13
5
5
2
reflections with F > 4σ(F). The extinction was accounted
for using SADABS program. The structure was solved
by the direct method and refined using SHELXTL soft-
ware. The refinement was carried out in the anisotropic
approximation for the nonhydrogen atoms. The positions
of hydrogen atoms were calculated geometrically and
refined in the rider model. The structural data are depos-
ited in Cambridge Crystallographic Data Center (CCDC
С 46.25; Н 1.49; Cl 10.50; F 28.14; N 4.15. M 337.63.
1
0-Chloro-6,7,8,9,10-pentafluoro-3-(4-methoxy-
phenyl)-1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-trienes
IVa, IVb were obtained similarly from 1.21 g (8 mmol)
of 4-methoxybenzaldoxime, 1.0 g (9 mmol) of tert-
butylhypochlorite, 100 ml of 10% NaOH solution,
and 0.44 g (2 mmol) of dienone I in 60 ml of CH Cl .
2
2
Yield 1.11 g (~76%), fluid containing according to the
9
18661) and are available free at the address: www.ccdc.
19
data of F NMR spectrum ~80% of diastereomers
cam.ac.uk/data_request/cif.
IVa, IVb, 84 : 16, ~6% of 8-chloro-6,7,8,9,10-pentaf-
luoro-3-(4-methoxyphenyl)-1,4-dioxa-2-azaspiro[4.5]
deca-2,6,9-triene, and ~12% of 10-chloro-6,8,9,10-tet-
rafluoro-3-(4-methoxyphenyl)-7-(pentafluorophenoxy)-
1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-triene IXа, IXb.
Polyfluorinated cyclohexa-2,4-dienones I, II, and
also the mixture of dienones X, XI were prepared by
procedures [7, 12]. Cyclohexadienone I contained ~6-
7
% of pentafluorophenol and ~5–6% of 4-chloropenta-
1
fluorocyclohexa-2,4-dienone that also reacted with aryl
nitrile oxides forming fluorine-substituted 1,4-dioxa-
Н NMR spectrum, δ, ppm, diastereomers IVa, IVb and
compounds IXа, IXb: 3.89 s (3Н, OСН ), 7.94–7.01 m
3
1
9
2
-azaspiro[4.5]deca-2,6,9-trienes [3] isomeric to target
compounds III–VI.
0-Chloro-6,7,8,9,10-pentafluoro-3-phenyl-1,4-
(2Harom), 7.64–7.79 m (2Harom). F NMR spectrum, δ,
ppm, diastereomer IVа: 6.4 d.d.t (1F, F , J 17, 4, ~3 Hz),
.5 d.d.t (1F, F , J 11, 6, ~3 Hz), 6.8 d.d.t (1F, F , J 20, 17,
3 Hz), 9.7 d.m (1F, F , J 6 Hz), 24.7 d.d.d.d (1F, F , J 20,
1, 4, ~2 Hz). F NMR spectrum, δ, ppm, diastereomer
IVb: 7.2 d.d.t (1F, F , J 12, 6, ~2 Hz), 7.3 d.d.t (1F, F ,
J 17, 6, ~2 Hz), 8.4 d.d.t (1F, F , J 23, 17, ~3 Hz), 9.4 d.m
1F, F , J 6 Hz), 30.7 d.d.d.d (1F, F , J 23, 12, 6, ~3 Hz).
F NMR spectrum, δ, ppm, compound IXа: 0.7 m (2F,
F ), 3.4 t (1F, F ), 6.0 m (2F, F ), 6.8 m (1F, F ), 8.9 d.m
1F, F , J 11 Hz), 11.4 d.m (1F, F , J 17 Hz), 23.4 d.d.d
1F, F , J 19, 11, 4 Hz). Found, %: С 46.09; Н 1.72; Cl
6
8
9
6
~
1
1
7
10
dioxa-2-azaspiro[4.5]deca-2,6,8-trienes IIIa, IIIb. To
a solution of 0.40 g (3.3 mmol) of benzaldoxime in 30 ml
of CH Cl at 4°С was added dropwise under stirring 0.44
1
9
8
6
2
2
9
g (4 mmol) of tert-butyl-hypochlorite in 5 ml of CH Cl .
2
2
7
10
(
1
The mixture was stirred for 1 h at 4°С, then it was shaken
with 50 ml ~10% water solution of NaOH cooled to 7°С.
The organic phase was separated and dried with solid
NaOH at –18°С for 15–20 min. The obtained solution
of benzonitrile oxide was added at stirring to a solution
of 0.44 g (2 mmol) of 6-chloropentafluorocyclohexa-
9
m
p
o
9
8
6
(
(
1
0
9
.41; F 25.76; N 3.52. M 366. С H ClF NO . Calculated,
14 7 5 3
%: С 45.74; Н 1.92; Cl 9.64; F 25.84; N 3.81. M 367.66.
2
,4-dienone (I) in 20 ml of CH Cl cooled to –18°С,
2 2
the reaction mixture was stirred for 2 h gradually
warming to 20°С, and 16 h at room temperature. On
evaporation the residue (0.88 g) was chromatographed
3-(4-Bromophenyl)-10-chloro-6,7,8,9,10-penta-
fluoro-1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-trienes
Va, Vb were similarly obtained from 0.6 g (3 mmol)
of 4-bromobenzaldoxime, 0.44 g (4 mmol) of tert-
butylhypochlorite, 80 ml of 10% NaOH solution, and
0.44 g (2 mmol) of dienone I in 55 ml of CH Cl . Yield
on a column packed with SiO . By the elution with a
2
mixture petroleum ether–CCl , 1 : 1, 0.53 g (79%) of
4
1
9
fluid was isolated containing according to F NMR
data 91% of diastereomers IIIa, IIIb, 85 : 15. Н NMR
2
2
1
0.71 g (85%), oily substance containing according to the
1
9
spectrum, δ, ppm, diastereomers IIIa, IIIb: 7.33–7.46 m
data of F NMR spectrum 89% of diastereomers Va,
Vb, 86 : 14. After double crystallization from hexane we
obtained 0.32 g of a crystalline mixture of diastereomers
1
9
(
3Harom), 7.67–7.71 m (2Harom). F NMR spectrum, δ,
6
ppm, diastereomer IIIа: 6.2 d.d.t (1F, F , J 17, 4, ~3 Hz),
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 8 2013

REACTION OF POLYFLUORINATED CYCLOHEXA-2,4-DIENONES
1219
1
6
10
Va, Vb, 96:4, mp 90–93°С. Н NMR spectrum, δ,
(1F, F , J 17, 4 Hz), 23.4 d.d.d (1F, F , J 20, 11, 4 Hz).
1
9
ppm, diastereomer Va: 7.66, 7.71 (4Harom, АВ system,
J ~8.5 Hz). F NMR spectrum, δ, ppm, diastereomer Vа:
.9 d.d.t (1F, F , J 17, 4, ~3 Hz), 6.7 d.d.t (1F, F , J 11,
, ~3 Hz), 7.0 d.d.t (1F, F , J 20, 17, ~3 Hz), 10.6 d.m
F NMR spectrum, δ, ppm, diastereomer VIIb: 0.7 m
19
m
p
o
9
(2F, F ), 3.5 t (1F, F ), 6.0 m (2F, F ), 8.6 d.d.d (1F, F ,
6
8
8
5
6
(
J 23, 17, ~2 Hz), 9.9 d.m (1F, F , J 12 Hz), 11.9 d.d.m
9
6
10
(1F, F , J 17, 5 Hz), 30.3 d.d.d (1F, F , J 23, 12, 5 Hz).
Found, %: С 46.19; Н 1.01; Cl 7.08; F 33.88; N 2.44.
M 494. С H ClF NO . Calculated, %: С 45.49; Н 1.00;
7
10
1F, F , J 6 Hz), 24.3 d.d.d.d (1F, F , J 20, 11, 4, ~2 Hz).
+
79 35
Found [M] 414.9026. С H Br ClF NO . Calculated
1
3
4
5
2
19
5
9
3
M 414.9029.
Cl 7.07; F 34.08; N 2.79. M 501.69.
The mother liquor contained 0.37 g of a mixture of
diastereomers Va, Vb in a ratio 67:22. F NMR spectrum,
6,7,8,9,10-Pentafluoro-10-(pentafluorophenoxy)-
3-phenyl-1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-trienes
XIIа, XIIb were obtained similarly to compounds IIIа,
IIIb from 0.36 g (3 mmol) of benzaldoxime, 0.40 g (3.7
mmol) of tert-butylhypochlorite, 50 ml 10% NaOH solu-
tion, and 0.73 g (2 mmol) of the mixture of dienones X,
19
6
8
δ, ppm, diastereomer Vb: 7.0 m (1F, F ), 7.5 d.d.t (1F, F ,
9
J 12, 6, ~3 Hz), 8.6 d.d.t (1F, F , J 23, 17, ~3 Hz), 10.2 d.m
1F, F , J 6 Hz), 30.7 d.d.d.d (1F, F , J 23, 12, 6, ~3 Hz).
7
10
(
1
0-Chloro-6,7,8,9,10-pentafluoro-3-(3-nitro-
XI, 33:67, in 55 ml of CH Cl . Yield 0.74 g (76%). Oily
phenyl)-1,4-dioxa-2-azaspiro[4.5]deca-2,6,8-trienes
VIa, VIb were similarly obtained from 1.02 g (6 mmol)
of 3-nitrobenzaldoxime, 0.87 g (8 mmol) of tert-
butyl-hypochlorite, 50 ml of 10% NaOH solution, and
2
2
19
substance containing according to the data of F NMR
spectrum 29% of diastereomers VIIIa, VIIIb, 54:46,
(
cf. [3]) and 69% of diastereomers XIIa, XIIb, ~97 : 3.
1
9
F NMR spectrum, δ, ppm, diastereomer (XIIa): 1.0 m
0
0
.44 g (2 mmol) of dienone I in 65 ml of CH Cl .Yield
2 2
m
9
8
(2F, F ), 4.9 d.d (1F, F , J 16, 15 Hz), 6.0 d.m (1F, F ,
.46 g (60%), fluid containing according to the data of
F NMR spectrum 87% of diastereomers VIa, VIb,
p
7
6
1
9
J 15 Hz), 6.5 t (1F, F ), 9.2 m (1F, F ), 10.0 d.m (1F, F ,
J 16 Hz), 10.5 m (2F, F ), 20.4 quintet (1F, F , J 15 Hz).
Found, %: С 46.87; Н 1.13; F 39.15; N 2.28. M 485.
o
10
6:14. 1 F NMR spectrum, δ, ppm, diastereomer VIа:
9
8
5
6
(
1
6
8
.6 d.d.t (1F, F , J 17, 4, ~3 Hz), 7.2 d.d.t (1F, F , J 11,
9
С H F NO . Calculated, %: С 47.03; Н 1.04; F 39.15;
, ~3 Hz), 7.3 d.d.t (1F, F , J 20, 17, ~3 Hz), 11.4 d.m
1F, F , J 6 Hz), 25.1 d.d.d.d (1F, F , J 20, 11, 4, ~2 Hz).
19 5 10 3
7
10
N 2.89. M 485.24.
9
F NMR spectrum, δ, ppm, diastereomer VIb: 6.4 d.d.t
3-(4-Bromophenyl)-6,7,8,9,10-pentafluoro-8-
(pentafluorophenoxy)-1,4-dioxa-2-azaspiro[4.5]
deca-2,6,9-trienes XIIIa, XIIIb. To a solution of 0.32 g
(0.8 mmol) of a mixture of compounds Vа, Vb, 96 :
6
8
(
~
1F, F , J 17, ~5, ~2 Hz), 7.8 d.d.t (1F, F , J 12, 6,
9
2 Hz), 8.5 d.d.t (1F, F , J 23, 17, ~2 Hz), 11.2 d.m (1F,
7
10
F , J 6 Hz), 29.7 d.d.d.d (1F, F , J 23, 12, ~5, ~2 Hz).
0-Chloro-6,8,9,10-tetrafluoro-7-(pentafluoro-
phenoxy)-3-phenyl-1,4-dioxa-2-azaspiro[4.5]deca-
,6,8-trienes VIIа, VIIb. To a solution of 0.22 g (1 mmol)
of dienone I in 10 ml of CH Cl was added by small
4
0
, in 5 ml of acetonitrile was added by small portions
.21 g (1 mmol) of sodium pentafluorophenolate, and
1
the mixture was stirred for 16 h at room temperature.
On evaporating the solvents the residue (~0.6 g) was
2
2
2
chromatographed on a column packed with SiO . Elut-
portions 0.21 g (1 mmol) of sodium pentafluorophenolate
7]. The mixture was stirred for 2 h at 20°С, cooled to
°С, and a cooled to –18°С solution of benzonitrile
oxide obtained from 0.36 g (3 mmol) of benzaldoxime,
.43 g (4 mmol) of tert-butyl-hypochlorite, and 50 ml
of 10% NaOH solution in 40 ml of CH Cl was added.
2
ing first with a mixture petroleum ether–CCl , 1 : 1, and
[
0
4
further with CCl we isolated 0.36 g (64%) of a substance
4
1
9
containing according to the data of F NMR spectrum
8
7% of diastereomers XIIIa, XIIIb, 81 : 19.
0
6,7,8,9,10-Pentafluoro-3-(3-nitrophenyl)-8-
2
2
The reaction was further performed analogously to the
(pentafluorophenoxy)-1,4-dioxa-2-azaspiro[4.5]
deca-2,6,9-trienes XIVa, XIVb were similarly obtained
from 0.37 g (1 mmol) of the mixture of compounds
VIа, VIb, 86:14, and 0.21 g (1 mmol) of sodium
pentafluorophenolate in 5 ml of acetonitrile. Yield
0.47 g, oily substance containing according to the data of
F NMR spectrum ~60% of diastereomers XIVa, XIVb,
77 : 23, and ~23% of compounds VIа, VIb, 78:22. After
double crystallization from ethanol we obtained 0.21 g of
synthesis of IIIа, IIIb. We obtained 0.40 g (80%) of oily
1
9
substance containing according to the data of F NMR
spectrum ~96% of diastereomers VIIa, VIIb, 84:16.
1
Н NMR spectrum, δ, ppm, diastereomers VIIа, VIIb:
1
9
7
.49–7.62 m (3Harom), 7.81–7.89 m (2Harom). F NMR
m
19
spectrum, δ, ppm, diastereomer VIIа: 0.7 m (2F, F ),
3
1
p
o
9
.5 t (1F, F ), 6.0 m (2F, F ), 6.9 d.d.d (1F, F , J 20,
8
7, ~3 Hz), 9.1 d.d.m (1F, F , J 11, ~5 Hz), 11.0 d.d.m
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 8 2013

1
220
KOVTONYUK, GATILOV
(1F, F7, J 21 Hz), 41.9 t.t.d (1F, F8, J 21, 13, 9 Hz). Found
1
crystalline diastereomer XIVa, mp 126–129°С. Н NMR
spectrum, δ, ppm, diastereomer XIVa: 7.81 t (1Нarom
J 8 Hz), 8.19 d.d.d (1Нarom, J 8, 2, 1 Hz), 8.48 d.d.d
+
M 648.9973. C H F NO . Calculated M 648.9990.
,
25
5
14
4
1
9
REFERENCES
(
1Нarom, J 8, 2, 1 Hz), 8.62 t (1Нarom, J 2 Hz). F NMR
spectrum, δ, ppm, diastereomer XIVa (cf. [3]): 0.6 m (2F,
1
2
. Kobrina, L.S., Izv. Akad. Nauk, Ser. Khim., 2002, p. 1629.
. Kovtonyuk, V.N., Kobrina, L.S., Kataeva, O.M., and
Haufe, G., Eur. J. Org. Chem., 2005, p. 1178.
m
p
6,10
7,9
F ), 6.3 t (1F, F ), 7.5 m (2F, F ), 9.2 m (2F, F ), 10.4 m
o
8
(
2F, F ), 41.3 m (1F, F ). Found, %: С 43.34; Н 0.89;
F 36.00; N 5.28. M 531. С H F N O . Calculated, %:
1
9
4
10
2
5
3. Kovtonyuk, V.N., Kobrina, L.S., and Gatilov, Yu.V., Zh.
Org. Khim., 2012, vol. 48, p. 787.
С 43.03; Н 0.76; F 35.83; N 5.28. M 530.24.
,7,8,9,10-Pentafluoro-8-(pentafluorophenoxy)-
-phenyl-1,4-dioxa-2-azaspiro[4.5]deca-2,6,9-
4
. Kovtonyuk, V.N., Kobrina, L.S., Gatilov, Yu.V., Bagryan-
skaya, I.Yu., Fröhlich, R., and Haufe, G., J. Chem. Soc.,
Perkin Trans. 1, 2000, p. 1929.
6
3
trienes VIIIa, VIIIb and 6,7,8,9-tetrafluoro-8,10-
bis(pentafluorophenoxy)-3-phenyl-1,4-dioxa-2-
azaspiro[4.5]deca-2,6,9-trienes (XV). To a solution
of 0.66 g (1.4 mmol) of the mixture containing 29% of
compounds VIIIa, VIIIb, 54 : 46, and 69% of XIIa,
XIIb, ~97 : 3, in 10 ml of acetonitrile was added 0.22 g
5
. Akhmetova, N.E., Kostina, N.G., Mamatyuk, V.I.,
Shtark, A.A., and Shteingarts, V.D., Izv. SO, Akad. Nauk
SSSR, Ser. Khim., 1973, no. 14, issue 6, p. 86.
6. Nair, V., Radhakrishnan, K.V., Sheela, K.C., and Rath, N.P.,
Tetrahedron, 1999, vol. 55, p. 14199.
7
8
9
. Akhmetova, N.E., Kostina, N.G., and Shteingarts, V.D.,
Zh. Org. Khim., 1979, vol. 15, 2137.
. Awad, W.I., Omran, S.M.A.R., Sobhy, M. J. Org. Chem.,
(1 mmol) of sodium pentafluorophenolate, and the mix-
ture was stirred for 18 days at room temperature. After
the removal of acetonitrile the residue (~0.9 g) was
1
966, vol. 31, 331.
. Bogachev, A.A., Kobrina, L.S., Meyer, O.G.J., and
Haufe, G., J. Fluor. Chem., 1999, vol. 97, p. 135; Bo-
gachev, A.A., Bagryanskaya, I.Yu., Rybalova, T.V., Gati-
lov, Yu.V., and Kobrina, L.S., Zh. Obshch. Khim., 1996,
vol. 66, p. 1324.
chromatographed on the column packed with SiO .At the
2
elution in succession with petroleum ether and a mixture
petroleum ether–ethyl acetate, 200 : 1, we isolated 0.44
g of solid substance containing according to the data of
19F NMR spectrum, 87% of compounds VIIIa, VIIIb,
10. Clayton,A.B., Feast, W.J., Sayers, D.R., Stephens, R., and
Tatlow, J.C., J. Chem. Soc. C., 1971, p. 1183.
70:30, and 13% of compound XIIa. We also isolated 0.22
1
1. Doyle, A.M. and Pedler, A.E., J. Chem. Soc. C, 1971,
g of viscous fluid containing ~74% of compound XV.
p. 282.
1
9
F NMR spectrum, δ, ppm, diastereomer XV (cf. [3]):
1
2. Akhmetova, N.E., Shtark, A.A., and Shteingarts, V.D.,
Zh. Org. Khim., 1973, vol. 9, p. 1218; Kobrina, L.S.,
Kovtonyuk, V.N., Yakobson, G.G., Zh. Org. Khim., 1977,
vol. 13, p. 1331.
m
m'
p'
0
.2 m (2F, F ), 0.3 m (2F, F ), 3.4 t (1F, F ), 5.9 t (1F,
p
o'
9
F ), 6.6 m (2F, F ), 7.8 d.d.t (1F, F , J 21, ~6, ~5 Hz), 8.8
d.d.d (1F, F , J 9, 6, ~2 Hz), 10.3 m (2F, F ), 12.9 d.m
10
o
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 8 2013