Synthesis, mesomorphic and dielectric properties of 4-(cyanomethoxy)phenyl 4-alkoxybenzoates, 4-(cyanomethoxy)-4′-alkoxyazo- and -azoxybenzenes

Article abstract of DOI:10.1134/S1070428014050017

Preparation methods were developed for homologs of 4-(cyanomethoxy)phenyl 4-alkoxybenzoates (C₇, C₈, C₉), 4-(cyanomethoxy)-4′-alkoxyazo (C₂, C₃, C ₆), -azoxybenzenes (C₃, C₆) whose composition and structure were proved by elemental analysis and ¹H NMR spectra. 4-(Cyanomethoxy) group destabilizes the mesophase, consequently, only four among the compounds obtained exhibit the thermotropic nematic mesomorphism.

Full text of DOI:10.1134/S1070428014050017

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2014, Vol. 50, No. 5, pp. 615–620. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © S.A. Kuvshinova, V.A. Burmistrov, I.V. Novikov, K.M. Litov, V.V. Aleksandriiskii, O.I. Koifman, 2014, published in Zhurnal
Organicheskoi Khimii, 2014, Vol. 50, No. 5, pp. 631–636.
Synthesis, Mesomorphic and Dielectric Properties
of 4-(Cyanomethoxy)phenyl 4-Alkoxybenzoates,
4-(Cyanomethoxy)-4'-alkoxyazo- and -azoxybenzenes
S. A. Kuvshinovaa, V. A. Burmistrova,b, I. V. Novikova, K. M. Litova,
V. V. Aleksandriiskiia,b, and O. I. Koifmana,b
a Ivanovo State University of Chemical Engineering, Research Institute of Macroheterocyclic Compounds,
Sheremetevskii pr. 7, Ivanovo, 153000 Russia
e-mail: sofya.kuv@yandex.ru
b Institute of Solutions Chemistry, Russian Academy of Sciences, Ivanovo, Russia
Received December 27, 2013
Abstract—Preparation methods were developed for homologs of 4-(cyanomethoxy)phenyl 4-alkoxybenzoates
(С7, С8, С9), 4-(cyanomethoxy)-4'-alkoxyazo (С2, С3, С6), -azoxybenzenes (С3, С6) whose composition and
1
structure were proved by elemental analysis and Н NMR spectra. 4-(Cyanomethoxy) group destabilizes the
mesophase, consequently, only four among the compounds obtained exhibit the thermotropic nematic
mesomorphism.
DOI: 10.1134/S1070428014050017
and a number of other compounds with allyl, glycidyl,
and alkylhalo substituents [1].
Substances possessing liquid crystalline properties
attract close attention of researchers from various
fields of science and technology as theoretical and
practical objects. Both the mesomorphic state and the
intermediate phase possessing high anisotropy of
physical properties and a far orientation order contain
the keys to the understanding of solid and liquid states
and also wide application opportunities thus initiating
a real interest directed on the targeted synthesis of new
mesogenic structures. The main tool in the molecular
design in the synthetic chemistry of liquid crystals
consists in the variation of the polarity, length or
volume of the terminal fragments and in the search for
the procedures for introducing versatile terminal
substituents for mesogens structure modification.
As bifunctional mesogens capable of self-assembly by
forming hydrogen bonds the following compounds were
synthesized and investigated: 4'-(ω-hydroxyalkoxy)-
biphenyl-4-carbonitriles, 4-[4-(ω-hydroxyalkoxy)-
phenyldiazenyl]benzaldehydes, 4-[4-(ω-hydroxyalkoxy)-
phenyldiazenyl- and -azoxy]benzonitriles, 4-[4-(ω-
hydroxyalkoxy)phenyl]diazenylcinnamic acids and their
4-cyanophenyl esters, 4-(ω-hydroxyalkoxy)-4'-(2,2-
dicyanoethenyl)azobenzenes, etc. [2].
Materially all mesogens that we have previously
synthesized [1, 2] possess useful properties either as
efficient liquid-crystalline stationary phases for
analysis and separation of close boiling structural
isomers of various organic substances [3], or as
universal modifiers of compositions based on
thermoplastics and rubbers [4]. They can be also
applied as dopants of commercial liquid-crystalline
materials in order to improve their exploitation
characteristics.
Our research team has synthesized 4-[(4-
alkoxyphenyl)diazenyl]benzaldehydes, 4-[(4-
alkoxyphenyl)diazenyl]benzaldehyde oximes, N-(4-
alkoxybenzylidene)anilines, N-[4-(4-alkoxyphenylazo)
benzylidene]anilines, 4-({4-[(4-alkoxyphenyl)
diazenyl]benzylidene}amino)benzonitriles, 4-[(4-
alkoxyphenyl)diazenyl]cinnamic acids, 4-(4-
alkoxybenzoyloxy)cinnamic acids, 4-(2,3-epoxy-
propoxy)-4'-alkoxyazoxybenzenes, 4-(2,3-epoxy-
propoxy)- and 4-acryloylphenyl 4-alkoxybenzoates,
With the goal to investigate the effect of the
terminal cyanomethoxy fragment on the mesomorphic
and dielectric properties of mesogenic alkoxy-
615

KUVSHINOVA et al.
616
Scheme 1.
OCH2CN
OH
OH
COOH
COCl
O
O
HO
SOCl2
BrCH2CN
DMF, K2CO3
C
O
C
O
Py
CnH2n + 1
O
CnH2n + 1
O
CnH2n + 1
O
CnH2n + 1O
Ia-Ic
IIa-IIc
n = 7 (а), 8 (b), 9 (c).
Scheme 2.
.
OH
NO2
NH2 HCl
CnH2n + 1Hlg
H2, Ni-Ra
DMF, K2CO3
i-PrOH, HCl
O2N
CnH2n + 1
O
CnH2n + 1
O
OCH2C
OCH2CN
OH
1. NaNO2, HCl
OH
H2O2
BrCH2CN
AcOH
2. NaOH,
N
N
N
N
N
N
O
CnH2n + 1
O
CnH2n + 1
O
CnH2n + 1
O
IIIa-IIIc
IVa, IVb
III, n = 2 (а), 3 (b), 6 (c); IV, n = 3 (а), 6 (b).
substituted phenyl benzoates, azo- and azoxybenzenes
we obtained 4-(cyanomethoxy)phenyl 4-alkoxy-benzo-
ates IIа–IIc (Scheme 1), 4-(cyano-methoxy)-4'-alkoxy-
azobenzenes IIIа–IIIc, and 4-(cyanomethoxy)-4'-
alkoxyazoxybenzenes IVа and IVb (Scheme 2).
obtained by the alkylation of 4-nitrophenol with an
appropriate alkyl halide in DMF in the presence of
potassium carbonate [6]. 4-Alkoxyanilines were
obtained by hydrogenation of the corresponding 4-
nitroalkyl ethers in 2-propanol in the presence of
Raney nickel as catalyst. 4-Alkoxyanilines were
isolated as their hydrochlorides.
4-Hydroxyphenyl 4-alkoxybenzoates Iа–Ic were
obtained by condensation of preliminary synthesized
corresponding 4-alkoxybenzoyl chlorides with a five-
fold excess of hydroquinone in anhydrous pyridine at
30°С over 10 h [5]. Further alkylation of compounds
Iа–Ic at the hydroxy group with bromoacetonitrile in
DMF without heating within 72 h led to the formation
of esters IIа–IIc.
The catalytic hydrogenation proceeded with a high
rate (within 10–30 min depending on the amount of the
initial compound and catalyst) and in a practically
quantitative yield, whereas the use of the standard
reducers of the nitro group, e.g., tin(II) chloride,
provided the alkoxyanilines in 20–40% yield. The
diazotization of 4-alkoxyaniline hydrochlorides and
the azo coupling with phenol afforded 4-[(4-
alkoxyphenyl)diazenyl]phenols whose reaction with
bromoacetonitrile in DMF in the presence of
4-[(4-Alkoxyphenyl)diazenyl]phenols necessary for
the synthesis of 4-(cyanomethoxy)-substituted azo-
(IIIа–IIIc) and azoxybenzenes IVа and IVb were
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 50 No. 5 2014

SYNTHESIS, MESOMORPHIC AND DIELECTRIC PROPERTIES
617
(IIIа–IIIc), azoxybenzenes IVа and IVc with the data
of their polar analogs with polar terminal substituent
CN directly attached to the phenyl fragment [7] shows
that the 4-(cyanomethoxy) group destabilizes the
mesophase regardless of the nature of the bridging
group. This experimental fact may be due to the
distortion of the bonds conjugation system and to the
decrease in the anisotropy of the molecular
polarizability at the introduction of the spacer CH2
between the phenyl ring and the cyano group. The
thermomicroscopic examination of the synthesized 4-
(cyanomethoxy) compounds confirms as a whole the
general rules of appearance and stability of the
mesomorphic state. The thermal stability of the
mesophase depending on the type of the bridging
group decreases in the following succession: –N=N– >
–NON– >> –COO–. In all studied compounds the
melting point and the clearing-up temperatures are
characteristically decreasing with lengthening of the
chain of the terminal aliphatic substituent owing to its
loosening effect resulting in widening the temperature
range of mesophase existence and in its stabilization.
O
N
CnH2n + 1
O
N
OCH2CN
OCH2CN
A
CnH2n + 1
O
N
N
O
B
potassium carbonate without heating within 72 h gave
the target azo compounds IIIа–IIIc. 4-(Cyano-
methoxy)-azoxybenzenes IVа and IVb were obtained
by the oxidation of the corresponding azobenzenes with
42% hydrogen peroxide in acetic acid.
The composition and structure of compounds II–IV
were established by elemental analysis and Н NMR
spectroscopy. The features of Н NMR spectra of
azoxybenzenes IVа and IVb indicate that in the course
of the oxidation forms a mixture of position isomers А
and B in the ratio 45 : 55 (IVа, n = 3), 36 : 64 (IVb,
n = 6).
1
1
In order to estimate the possibility to use the
synthesized compounds as modifiers of liquid-
crystalline compositions we studied the dielectric
properties of 4-(cyanomethoxy)phenyl 4-(heptyloxy)
benzoate (IIа) and {4-[(4-hexyloxyphenyl)-ОNN
(NNO)-azoxy]phenoxy}acetonitrile (IVb). In Figs. 1, 2
experimental temeperature dependences of dielectric
permittivity ε are presented, in Fig. 3, the dependences
of dielectric permittivity anisotropy ∆ε on the reduced
temperature Tr = T – TNI (T is the measurement
temperature, TNI is the temperature of transition from
nematic to isotropic phase in the studied compounds).
The application of the reduced temperature scale
makes it possible to compare the dielectric
characteristics of mesogens with different phase
transition temperatures. Compounds IIа and IVb are
characterized by positive (ε║ > ε+) anisotropy and
sufficiently high values of the dielectric permittivity
owing to the presence in the terminal substituent of the
polar cyano group. The maximum values of dielectric
anisotropy equal ∆ε ~4 (IVb) and ~7 (IIа). The phase
transition temperatures measured by dielcometric
method are well consistent with the thermomicroscopic
findings.
The study of the mesomorphic properties of
compounds II–IV was performed with the use of
polarization thermomicroscopy. It was shown that
azobenzenes IIIа–IIIc and azoxybenzene IVа with the
short-chain aliphatic substituent did not form the
mesophase. Phenyl benzoates IIа and IIb transform
into liquid-crystalline state on cooling, namely, they
are monotropic nematics. Only compounds IIc and
IVb where the aliphatic substituents possess
sufficiently long chain are enantiotropic mesogens.
Below are presented the phase transitions temperatures
(±0.1°С) in the heating and cooling modes (C, N, and I
are crystalline, nematic, and isotropic-liquid phases,
respectively).
C 67.3 I
Heating
Cooling
IIа
IIb
IIc
I 52.3 N 42.0 C
C 70.0 I
Heating
Cooling
Heating
Cooling
Heating
Cooling
I 50.8 N 32.5 C
C 49.8 N 57.3 I
I 55.0 N 37.3 C
C 88.0 N 98.0 I
I 97.5 N 70.5 C
IVb
The multiplex characteristics of matrix devices
depend on the steepness of the volt-contrast
characteristics that is governed essentially by the value
of the ratio ∆ε/ε+. The smaller ∆ε/ε+, the higher is the
The comparison of phase transition temperatures of
synthesized phenyl benzoates IIа–IIc, azobenzenes
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 50 No. 5 2014

KUVSHINOVA et al.
steepness of the volt-contrast characteristics and the
618
ε
higher is the multiplexity level [8]. Below the values of
dielectric characteristics of mesogens IIa and IVb are
given, and also of eutectic mixtures of 4-pentyl- and
4'-heptylbiphenyl-4-carbonitriles (BF), 4'-pentyloxy-
and 4'-heptyloxybiphenyl-4-carbonitriles (OBF), and
liquid-crystalline composition LC-807 [8]. All values
correspond to Tr of −8°С.
20.0
ε║
ε┴
2
16.0
12.0
8.0
1
4.0
∆ε
5.70
3.93
11.73
9.90
8.35
ε+
12.32
12.44
6.05
∆ε/ε+
0.46
0.32
1.94
1.43
1.07
0.0
10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0
IIa
Т, °С
IVb
Fig. 1. Temperature dependences of dielectric permittivity
ε of mesogen IIa at heating (1) and cooling (2).
BF
OBF
LC-807
6.95
6.10
ε
18.0
2
ε║
As shows the analysis of experimental and
published [8] data mesogens IIa and IVb possess
significantly higher dielectric permittivity compared
with 4'-alkylbiphenyl- and 4'-alkoxybiphenyl-4-
carbonitriles which are included in multicomponent
mixtures for electrooptic devices for displaying
information. Yet mesogens IIa and IVb have worse
values of the dielectric anisotropy than BF, OBF, and
LC-807. At the same time the ratios ∆ε/ε+ of mesogens
IIa and IVb is considerably smaller than for the
mixtures based on biphenylcarbonitriles. In its turn it
should favorably affect the volt-contrast charac-
teristics of the liquid-crystalline materials at their
doping with 4-(cyanomethoxy)-substituted phenyl ben-
zoate IIa and azoxybenzene IVb.
16.0
14.0
12.0
10.0
8.0
1
ε┴
70.0
80.0
90.0
100.0
Т, °С
110.0
120.0
Fig. 2. Temperature dependences of dielectric permittivity
ε of mesogen IVb at heating (1) and cooling (2).
EXPERIMENTAL
Δε
8
1Н NMR spectra were registered on a high
resolution spectrometer Bruker Avance III at operating
frequency 500 МHz. Chemical shifts were measured
with respect to HMDS.
1
2
6
4
2
0
The phase state of compounds synthesized was
studied using a microscope Polam Р211 equipped with
a heating block with heating rate control in the range
from 0.1 to 3.5 deg min–1, operating temperatures 0–
300°С, and maintaining constant temperature for a
long time. For precise measuring the phase transition
temperature the thermal system was preliminary
calibrated using reference points of standard pure
chemical substance with the known melting points.
The accuracy of measuring temperature was ±0.1°С.
The microscope is equipped with a videocamera KPC-
–25
–20
–15
–10
–5
0
Тred
Fig. 3. Dependences of the anisotropy of dielectric
permittivity ∆ε on reduced temperature for mesogens IIа
(1) and IVb (2).
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 50 No. 5 2014

SYNTHESIS, MESOMORPHIC AND DIELECTRIC PROPERTIES
619
S230CWX (3.6 mm) providing a possibility to observe
the dynamics of phase transitions and to fix the phase
textures at any moment. The phase transition
temperatures were measured in heating and cooling
cycles. The samples were prepared as thin films
between cover and slide microscope glasses.
СН2, J 7.25 Hz), 4.06 t (2Н, ОСН2, J 6.52 Hz), 4.78 s
(2Н, СН2CN), 6.99 d (2Нarom, J 8.85 Hz), 7.05 d
(2Нarom, J 9.16 Hz), 7.20 d (2Нarom, J 8.85 Hz), 8.15 d
(2Нarom, J 8.85 Hz). Found, %: С 72.54; Н 7.15; N 3.20.
C24H29NO4. Calculated, %: С 72.91; Н 7.34; N 3.54.
{4-[(4-Ethoxyphenyl)diazenyl]phenoxy}aceto-
nitrile (IIIа). A mixture of 3.5 g (0.0145 mol) of 4-
[(4-ethoxyphenyl)diazenyl]phenol, 4 g (0.029 mol) of
K2CO3, and 3 g (0.025 mol) of bromoacetonitrile in
50 mL of DMF was stirred without heating for 72 h.
Then the reaction mixture was poured in 250 mL of ice
water. The reaction product was extracted from the
separated precipitate with chloroform, the organic
layer was thrice washed with water, dried with
anhydrous Na2SO4, the solvent was distilled off. The
residue was chromatographed on alumina (eluent
chloroform) and recrystallized from ethanol. Yield 2.1 g
(51%), yellow-orange lustrous crystals, mp 146.5°С
(EtOH). 1Н NMR spectrum, δ, ppm: 1.48 t (3Н, СН3, J
7.02 Hz), 4.14 q (2Н, ОСН2, J 7.02 Hz), 4.85 s (2Н,
СН2CN), 7.02 d (2Нarom, J 8.85 Hz), 7.10 d (2Нarom, J
9.16 Hz), 7.91 d (2Нarom, J 8.85 Hz), 7.93 d (2Нarom, J
8.85 Hz). Found, %: С 68.03; Н 5.24; N 14.77.
C16H15N3O2. Calculated, %: С 68.27; Н 5.38; N 14.94.
The dielectric permittivity was measured at the
frequency 10 кHz using an instrument LCR-817
(INSTEK) in a temperature-controlled (with accuracy
of ±0.05°С) plane-parallel cell with the gap of 0.2 mm
placed in the magnetic field of 0.2 Т. The error in
measuring ε did not exceed ±0.02.
4-(Cyanomethoxy)phenyl 4-(heptyloxy)benzoate
(IIа). A mixture of 6.56 g (0.02 mol) of 4-hydroxyphenyl
4-(heptyloxy)benzoate, 5.52 g (0.04 mol) of K2CO3, and
4.08 g (0.034 mol) of bromoacetonitrile in 80 mL of
DMF was stirred without heating for 72 h. Then the
reaction mixture was filtered and the filtrate was
poured in 250 mL of ice water. The reaction product
was extracted from the separated precipitate with
chloroform, the organic layer was thrice washed with
water, dried with anhydrous Na2SO4, the solvent was
distilled off. The residue was dried and recrystallized
from ethanol. Yield 2.36 g (32%), light-yellow
1
crystals, mp 67.3°С (EtOH). Н NMR spectrum, δ,
Azobenzenes IIIb and IIIc were similarly obtained.
ppm: 0.93 t (3Н, CH3, J 6.87 Hz), 1.35 m [4Н, (СН2)2],
1.40 m (2Н, СН2), 1.50 m (2Н, СН2, J 7.8 Hz), 1.84 m
(2Н, СН2, J 7.25 Hz), 4.06 t (2Н, ОСН2, J 6.52 Hz),
4.77 s (2Н, CH2CN), 6.99 d (2Нarom, J 8.85 Hz), 7.05 d
(2Нarom, J 9.16 Hz), 7.20 d (2Нarom, J 8.85 Hz), 8.15 d
(2Нarom, J 8.85 Hz). Found, %: С 71.03; Н 7.09; N
3.15. C22H25NO4. Calculated, %: С 71.93; Н 6.81; N
3.81.
{4-[(4-Propoxyphenyl)diazenyl]phenoxy}-
acetonitrile (IIIb). Yield 2.5 g (50%), yellow-orange
1
lustrous crystals, mp 134.1°С (EtOH). Н NMR spec-
trum, δ, ppm: 1.09 t (3Н, СН3, J 7.02 Hz), 1.81 sextet
(2Н, СН2, J 7.09 Hz), 4.03 t (2Н, ОСН2, J 6.60 Hz), 4.85
s (2Н, СН2CN), 7.02 d (2Нarom, J 8.85 Hz), 7.11 d
(2Нarom, J 9.16 Hz), 7.91 d (2Нarom, J 8.85 Hz), 7.94 d
(2Нarom, J 8.85 Hz). Found, %: С 69.07; Н 5.69; N
14.13. C17H17N3O2. Calculated, %: С 69.12; Н 5.81; N
14.23.
Esters IIb and IIc were similarly obtained.
4-(Cyanomethoxy)phenyl 4-(octyloxy)benzoate
(IIb). Yield 3.3 g (44%), light-yellow crystals, mp
1
{4-[(4-Hexyloxyphenyl)diazenyl]phenoxy}aceto-
nitrile (IIIc). Yield 3.3 g (49%), yellow-orange
lustrous crystals, mp 131.5°С (EtOH). 1Н NMR
spectrum, δ, ppm: 0.95 t (3Н, СН3, J 7.02 Hz), 1.38 m
[4Н, (СН2)2], 1.51 quintet (2Н, СН2, J 7.43 Hz), 1.84
quintet (2Н, СН2, J 7.29 Hz), 4.06 t (2Н, ОСН2, J 6.60 Hz),
4.85 s (2Н, СН2CN), 7.02 d (2Нarom, J 8.85 Hz), 7.11 d
(2Нarom, J 9.16 Hz), 7.91 d (2Нarom, J 8.85 Hz), 7.94 d
(2Нarom, J 8.85 Hz). Found, %: С 71.09; Н 6.76; N
12.39. C20H23N3O2. Calculated, %: С 71.18; Н 6.88; N
12.45.
70.0°С (EtOH). Н NMR spectrum, δ, ppm: 0.92 t
(3Н, СН3, J 6.87 Hz), 1.32 m [8Н, (СН2)4], 1.50 m
(2Н, СН2, J 7.8 Hz), 1.84 m (2Н, СН2, J 7.25 Hz),
4.05 t (2Н, ОСН2, J 6.52 Hz), 4.77 s (2Н, СН2CN),
6.99 d (2Нarom, J 8.85 Hz), 7.04 d (2Нarom, J 9.16 Hz),
7.20 d (2Нarom, J 8.85 Hz), 8.14 d (2Нarom, J 8.85 Hz).
Found, %: С 71.78; Н 6.34; N 3.54. C23H27NO4.
Calculated, %: С 72.44; Н 7.09; N 3.67.
4-(Cyanomethoxy)phenyl 4-(nonyloxy)benzoate
(IIc). Yield 3.8 g (48%), light-yellow crystals, mp
1
49.8°С (EtOH). Н NMR spectrum, δ, ppm: 0.91 t
{4-[(4-Hexyloxyphenyl)-ОNN(NNO)-azoxy]phen-
oxy}acetonitrile (IVb). In 40 mL of glacial acetic acid
(3Н, СН3, J 6.87 Hz), 1.32 m [8Н, (СН2)4], 1.39 m
(2Н, СН2), 1.50 m (2Н, СН2, J 7.8 Hz), 1.84 m (2Н,
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 50 No. 5 2014

KUVSHINOVA et al.
620
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was dissolved at 50–55°С 3.46 g (0.01 mol) of azo
compound IIIc, 20 mL of 42% hydrogen peroxide was
added dropwise, and the mixture was stirred at the
same temperature for 30 min. The reaction mixture
was poured into 300 mL of ice water. The reaction
product was filtered off, washed with water, dried, and
recrystallized from acetic acid and ethanol. Yield 2.31 g
1
(64%), yellow crystals, mp 88.0°С (EtOH). Н NMR
spectrum, δ, ppm, isomer А (ONN) (36%): 0.94 t (3Н,
СН3, J 6.74 Hz), 1.38 m (4Н, СН2), 1.497 m (2Н,
СН2), 1.83 m (2Н, СН2), 4.05 t (2Н, ОСН2, J 6.20 Hz),
4.86 s (2Н, СН2CN), 6.99 d (2Нarom, J 9.35 Hz), 7.07 d
(2Нarom, J 9.35 Hz), 8.31 d (2Нarom, J 9.08 Hz), 8.35 d
(2Нarom, J 9.08 Hz); isomer B (NNO) (64%): 0.94 t
(3Н, СН3, J 6.74 Hz), 1.37 m (4Н, СН2), 1.497 m (2Н,
СН2), 1.83 m (2Н, СН2), 4.04 t (2Н, ОСН2, J 6.60 Hz),
4.84 s (2Н, СН2CN), 6.97 d (2Нarom, J 9.08 Hz), 7.07 d
(2Нarom, J 9.35 Hz), 8.25 d (2Нarom, J 9.08 Hz), 8.29 d
(2Нarom, J 9.35 Hz). Found, %: С 67.83; Н 6.48; N
11.72; О 13.53. C20H23N3O3. Calculated, %: С 67.96;
Н 6.57; N 11.89; О 13.58.
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J. Org. Chem., 2009, vol. 45, p. 182; Litov, K.M.,
Kuvshinova, S.A., Burmistrov, V.A., Aleksandriiskii, V.V.,
Potemkina, O.V., and Koifman, O.I., Zhid. Krist. Prakt.
Ispol., 2013, no. 44, p. 5.
{4-[(4-Propoxyphenyl)-ОNN(NNO)-azoxy]phen-
oxy}acetonitrile (IVа) was prepared similarly. Yield
1
3. Lobanova, S.A., Shcherbakova, O.A., Burmistrov, V.A.,
and Koifman, O.I., Izv. Vuzov, Ser. Khim. i Khim.
Tekhnol., 1989, vol. 63, p. 1223; Burmistrov, V.A.,
Shcherbakova, O.A., Kareev, V.U., and Koifman, O.I.,
Zh. Analit. Khim., 1990, vol. 45, p. 1781; Fokin, D.S.,
Kuvshinova, S.A., Burmistrov, V.A., Blokhina, S.V.,
and Koifman, O.I., Zhid. Krist. Prakt. Ispol., 2009, no. 27,
p. 71; Kuvshinova, S.A., Burmistrov, V.A., Fokin, D.S.,
Blokhina, S.V., and Koifman, O.I., Zh. Analit. Khim.,
2009, vol. 64, p. 505; Kuvshinova, S.A., Fokin, D.S.,
Litov, K.M., Burmistrov, V.A., and Koifman, O.I.,
Russ. J. Phys. Chem. A, 2010, vol. 84, p. 1956.
2 g (64%), yellow crystals, mp 118.7°С (EtOH). Н
NMR spectrum, δ, ppm, isomer А (ONN) (45%): 1.08 t
(3Н, СН3, J 7.43 Hz), 1.86 m (2Н, СН2, J 7.14 Hz),
4.02 t (2Н, ОСН2, J 6.46 Hz), 4.85 s (2Н, СН2CN),
6.99 d (2Нarom, J 9.35 Hz), 7.07 d (2Нarom, J 9.35 Hz),
8.31 d (2Нarom, J 9.08 Hz), 8.35 d (2Нarom, J 9.08 Hz);
isomer B (NNO) (55%): 1.08 t (3Н, СН3, J 7.43 Hz),
1.87 m (2Н, СН2, J 7.14 Hz), 4.01 t (2Н, ОСН2, J 6.60 Hz),
4.84 s (2Н, СН2CN), 6.97 d (2Нarom, J 9.08 Hz), 7.07 d
(2Нarom, J 9.35 Hz), 8.25 d (2Нarom, J 9.08 Hz), 8.29 d
(2Нarom, J 9.35 Hz). Found, %: С 65.42; Н 5.38; N
13.47; О 15.30. C17H17N3O3. Calculated, %: С 65.57;
Н 5.51; N 13.50; О 15.42.
4. Fokin, Dm.S., Kuvshinova, S.A., Vasil’ev, D.M., and Bur-
mistrov, V.A., Zhid. Krist. Prakt. Ispol., 2009, no. 29, p. 14.
5. Schroeder, D.C. and Schroeder, J.-P., J. Org. Chem.,
This work was supported by the Presidium of the
Russian Academy of Sciences (program of
fundamental research no. 24) and the Russian Foun-
dation for Basic Research (project no. 12-03-00370-a).
1972, vol. 37, p. 1425.
6. Burmistrov, V.A., Kuzmina, S.A., and Koifman, O.I.,
Zh. Org. Khim., 1995, vol. 31, p. 388.
7. Dabrowski, R., Adamska, G., Stolarzowa, Z., and
Konarzewski, A., Pol. J. Chem., 1980, vol. 54, p. 1233;
Lazareva, V.T., Titov, V.V., and Roitman, K.V., Zh.
Org. Khim., 1976, vol. 12, p. 149; van der Veen, J., and
Hegge, T.C.J.M., Angew. Chem., 1974, vol. 86, p. 378.
REFERENCES
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