Synthesis of N,N′-bis-[3-alkoxy-4-(hydroxy, alkoxy, acyloxy)-phenylmethylene- and -Phenylmethyl]-1,3-phenylenediamines

Article abstract of DOI:10.1134/S1070363209020157

Starting with the vanillin series aldehydes, by reaction with 1,3-phenylenediamine in absolute methanol E,E-N,N′-bis-[3-alkoxy-4- (hydroxy-, alkoxy-, acyloxy)phenylme-thylene]-1,3-phenyl-enediamines (Shiff bases) are synthesized from reduction with Na[BH(

Full text of DOI:10.1134/S1070363209020157

ISSN 1070-3632, Russian Journal of General Chemistry, 2009, Vol. 79, No. 2, pp. 258–263. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © E.A. Dikusar, V.I. Potkin, N.G. Kozlov, A.P. Yuvchenko, 2009, published in Zhurnal Obshchei Khimii, 2009, Vol. 79, No. 2,
pp. 269–274.
Synthesis of N,N'-bis-[3-alkoxy-4-(hydroxy, alkoxy, acyloxy)-
phenylmethylene- and -Phenylmethyl]-1,3-phenylenediamines
E. A. Dikusara,b, V. I. Potkina, N. G. Kozlova,b, and A. P. Yuvchenkob
a Institute of Physico-Organic Chemistry, National Academy of Sciences of Belarus,
ul. Urganova 13, Minsk, 220072 Belarus’
e-mail: evgen_58@mail.ru
b Institute of the Chemistry of New Materials, National Academy of Sciences of Belarus, Minsk, Belarus
Received September 17, 2008
Abstract―Starting with the vanillin series aldehydes, by reaction with 1,3-phenylenediamine in absolute
methanol E,E-N,N'-bis-[3-alkoxy-4-(hydroxy-, alkoxy-, acyloxy)phenylme-thylene]-1,3-phenyl-enediamines
(Shiff bases) are synthesized from reduction with Na[BH(OAc)3] in benzene were prepared respective N,N'-bis-
[3-alkoxy-4-(hydroxy-, alkoxy-, acyloxy)phenylmethyl]-1,3-phenyl-enediamines.
DOI: 10.1134/S1070363209020157
We have reported earlier on the synthesis of N,N'-
bis-[3-alkoxy-4-(hydroxy-, alkoxy-, acyloxy)phenyl-
methylene]-1,4-phenylenediamines and 2-[3-alkoxy-4-
(hydroxy-, alkoxy-, acyloxy)phenyl]-2,3-dihydro-1Н-
benzimidazoles by the condensation of vanillin series
aldehydes with 1,4- and 1,2-phenylenediamines [1, 2].
Aromatic azomethines are interesting substances for
producing from tem nano-films and nano-materials and
studying their biological activity [3, 4].
The aim of this work is developing a preparative
procedure for the synthesis of aromatic bis-
azomethines possessing hydroxy, ether and ester
groups by condensation of vanillin series aldehydes I
with 1,3-phenylenediamine II (reagents ratio 2:1) in
the medium of absolute methanol at the temperature of
this solvent boiling. We prepared aromatic bis-
azomethines (Shiff bases) (IIIa–IIIu, IVa–IVk) with
preparative yield 80–90%.
R1
R1
R
R
O
NH2
N
HN
Na[BH(OAc)3]
+
R
NH2
N
NH
R1
R
R
R1
R1
I
II
IIIа−IIIu, IVа−IVk
Vа−Vu, VIа−VIk
III, V, R = R1 = H (a); R = H, R1 = MeO (b); R = MeO, R1 = HO (c), MeO (d), MeC(O)O (e), EtC(O)O (f), PrC(O)O (g),
Me2CHC(O)O (h), Me(СH2)6C(O)O (i), Me(СH2)8C(O)O (j), Me(СH2)16C(O)O (k), H2C=CMeC(O)O (l), C6H5CH2C(O)O
(m), С6H5СHMeCH2C(O)O (n), C6H5C(O)O (o), 4-СlС6H4C(O)О (p), 2,4-Сl2С6H3C(O)О (q), 4-BrС6H4C(O)О (r), 3-
O2NС6H4C(O)О (s), MeOC(O)О (t), EtOC(O)О (u); IV, VI, R = EtO, R1 = HO (a), MeO (b), MeC(O)O (c), EtC(O)O (d),
PrC(O)O (e), Me2CHC(O)O (f), Me2CHСH2C(O)O (g), 4-MeС6H4C(O)О (h), 3,5-(O2N)2С6H3C(O)О (i), MeOC(O)О (j),
EtOC(O)О (k).
258

259
SYNTHESIS OF N,N'-BIS-[3-ALKOXY-4-(HYDROXY, ALKOXY, ACYLOXY)
Reaction completed in 10–15 min and proceeded
under mild conditions without a catalyst, that promoted
retaining of labile ester groups [3].
reaction carried out at specially gathered gentle tem-
perature regime and acid action [5] we did not observe
proceeding of side reaction of reduction of ester, nitro
and unsaturated methacrylic groups in side chains.
The obtained bis-azomethines IIIa–IIIu, IVa–IVk
were reduced with a mild reducing agent sodium tetra-
acetoxyboron hydride Na[BH(OAc)3] in benzene at 20–
23°С. Reduction of aromatic bis-azomethines IIIa–IIIu,
IVa–IVk to respective secondary diamines Va–Vu,
VIa–VIk was completing in 18–20 h. Yield of secondary
diamines Va–Vu, VIa–VIk was practically quantitative,
actually 94–96%. Under the conditions of the reduction
At the condensation of vanillin succinate and
vanillal VIIa, VIIb with 1,3-phenylenediamine II
(ratio of the reagents 1:1) by the similar scheme were
prepared oligomeric cyclic azomethines (Shiff bases)
VIIIa, VIIIb in preparative yield 92–93%. Reduction
of these compounds with Na[BH(OAc)3] led to oligo-
meric cyclic amines IХa, IXb in 94–96% yield.
O
N
HN
NH2
N
NH
Na[BH(OAc)3]
+
RO
NH2
O
OR
RO
O
OR
RO
O
O
O
O
O
O
2
O
O
n
n
VIIа, VIIb
II
IXа, IXb
VIIIа, VIIIb
VII–IX, R = Me (a), Et (b), n = 1–8.
1
Structures of the synthesized azomethines and
secondary amines IIIa–IIIu, IVa–IVk, Va–Vu, VIa–
VIk, VIIIa, VIIIb, IXa, and IXb are confirmed by the
data of elemental analysis, cryoscopic determining of
In the Н NMR spectra of compounds IIIb–IIIu,
IVb, Vb–Vu, and VIb the signals of МeО group
protons appear as a singlet in the range from 3.85 to
3.92 ppm, in the spectra of compounds IVa–IVk and
VIa–VIk there are the signals of EtO group protons as
a triplet at 1.10–1.45 ppm (Мe) and a quadruplet at
3.90-4.30 ppm (СН2). The signals of aromatic protons
in compounds IIIa–IIIu, IVa–IVk, Va–Vu, and VIa–
VIk are located in the range of 6.90–7.40 ppm. The
proton of azomethine group (HC=N) in compounds
IIIa–IIIu and IVa–IVk induces a singlet in the region
of 8.45–8.55 ppm, that is characteristic of azomethine
1
molecular mass (Table 1), IR and H NMR spectra.
1
According to the H NMR spectra, purity of the ob-
tained compounds is 96±2%.
In the IR spectra of compounds IIIa–IIIu, IVa–
IVk, Va–Vu, Via–VIk, VIIIa, VIIIb, IXa and IXb
there are absorption bands of the bonds С–HAr in the
regions of 3080–3070, 3005–3002, 870–700; С–НAlk
2970–2830; C=O 1765–1730; С–CAr 1610–1590,
1505–1500, 1466–1460, 1418–1410, 1375-1366; С–О
1280–1260, 1210–1190, 1150–1110, 1035–1030 cm–1.
In the IR spectra of azomethines IIIa–IIIu, IVa–IVk,
VIIIa, and VIIIb there is a characteristic absorption
band of C=N group in the region of 1630–1627 cm–1,
that is absent in the spectra of amines Va–Vu, VIa–
VIk, IXa, and IXb. In the IR spectra of amines Va–
Vu, VIa–VIk, IXa, and IXb appears characteristic N–
Н absorption band in the region of 3420–3375 cm–1. In
the IR spectra of nitro compounds IIIs, IVi, Vs, and
VIi occurs absorption bands of NO2 group at 1544–
1528 and 1350–1345 cm–1.
1
Е-isomers [1–3]. In the H NMR spectra of secondary
amines Va–Vu and VIa–VIk there are the signals of
СН2 group protons (СH2NH) as a broad singlet in the
1
region of 4.40–4.42 ppm. The Н NMR spectra of
compounds VIIIa, VIIIb, IXa, and IXb were not
recorded due to low solubility of these compounds. By
the same reasons their molecular weighs were not
determined.
In the IR and 1Н NMR spectra of azomethines and
secondary amines IIIa–IIIu, IVa–IVk, Va–Vu, VIa–
VIk, VIIIa, VIIIb, IXa, and IXb occur also all absorp-
tion bands and proton signals confirming presence of
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 2 2009

260
DIKUSAR et al.
Table 1. Yields, melting points, data of elemental anlysis and molecular weghts of compounds IIIa–IIIu, IVa–IVk, Va–Vu,
VIa–VIk, VIIIa, VIIIb, IXa, and IXb
Found, %
H
Calculated, %
H
М
Comp.
no.
Yield, %
mp, °С
Formula
C
N
9.35
7.84
7.08
6.60
5.82
5.43
5.12
5.12
4.05
3.87
2.62
4.14
4.19
3.88
4.36
4.02
3.72
3.45
8.02
5.32
5.14
6.65
6.22
5.40
5.11
4.82
4.80
4.53
4.09
10.21
5.06
4.83
C
N
found
275.7
338.0
368.2
396.3
453.8
481.2
508.6
505.9
620.4
673.0
896.5
504.7
604.8
659.8
576.4
644.7
708.2
732.1
665.4
484.3
512.3
392.8
418.7
475.0
507.2
536.4
532.5
565.7
651.2
781.6
511.6
534.9
calculated
284.4
344.4
376.4
404.5
460.5
488.5
516.6
516.6
628.8
684.9
909.3
512.6
612.7
668.8
584.6
653.5
722.4
742.4
674.6
492.5
520.5
404.5
432.5
488.5
516.6
544.6
544.6
572.7
640.7
792.7
520.5
548.6
85
89
80
85
90
88
90
87
87
90
82
80
81
84
90
86
85
86
88
90
85
82
84
88
87
84
88
87
90
88
82
85
154–155
113–114
138–139
122–123
126–127
85–86
84.91
77.03
70.62
71.48
68.12
68.04
70.03
69.97
72.84
73.90
76.94
70.51
74.69
75.76
74.10
66.39
60.01
58.65
64.28
63.87
65.03
71.56
72.54
69.00
69.98
70.86
70.93
71.62
75.23
75.87
64.87
65.84
5.76
5.96
5.43
6.14
5.36
5.80
6.32
6.34
7.75
8.33
9.92
5.52
5.35
6.14
4.90
4.13
3.40
3.72
3.95
5.05
5.58
6.10
6.59
5.87
6.32
6.84
6.79
7.18
5.66
3.65
5.62
5.99
C20H16N2
84.48
76.72
70.20
71.27
67.82
68.84
69.75
69.75
72.58
73.65
76.61
70.30
74.50
75.43
73.96
66.16
59.85
58.24
64.09
63.41
64.61
71.27
72.20
68.84
69.75
70.57
70.57
71.31
74.98
75.58
64.61
65.58
5.67
5.85
5.36
5.98
5.25
5.78
6.24
6.24
7.69
8.24
9.75
5.51
5.26
6.03
4.83
4.01
3.35
3.53
3.88
4.91
5.42
5.98
6.52
5.78
6.24
6.66
6.66
7.04
5.66
3.56
5.42
5.88
9.85
8.13
7.44
6.93
6.08
5.73
5.42
5.42
4.46
4.09
3.08
4.47
4.57
4.19
4.79
4.29
3.88
3.77
8.30
5.69
5.38
6.93
6.48
5.73
5.42
5.14
5.14
4.89
4.37
10.60
5.38
5.11
IIIa
IIIb
IIIc
IIId
IIIe
IIIf
IIIg
IIIh
IIIi
C22H20N2О2
C22H20N2О4
C24H24N2О4
C26H24N2О6
C28H28N2О6
C30H32N2О6
C30H32N2О6
C38H48N2О6
C42H56N2О6
C58H88N2О6
C30H28N2О6
C38H32N2О6
C42H40N2О6
C36H28N2О6
C36H26Сl2N2О6
C36H24Сl4N2О6
C36H26Br2N2О6
C36H26N4О10
C26H24N2О8
C28H28N2О8
C24H24N2О4
C26H28N2О4
C28H28N2О6
C30H32N2О6
C32H36N2О6
C32H36N2О6
C34H40N2О6
C40H36N2О6
C38H28N6О14
C28H28N2О8
C30H32N2О8
138-139
194–195
111–112
92–93
IIIj
IIIk
IIIl
53–54
106–107
137–138
88–89
IIIm
IIIn
IIIo
IIIpа
IIIqb
IIIrc
IIIs
IIIt
IIIu
IVa
IVb
IVc
IVd
IVe
IVf
138–139
96–97
92–93
115–116
144–145
120–121
88–89
56–57
151–152
77–78
82–83
118–119
125–126
143–144
133–134
140–141
84–86
IVg
IVh
IVi
IVj
132–133
IVk
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 2 2009

261
SYNTHESIS OF N,N'-BIS-[3-ALKOXY-4-(HYDROXY, ALKOXY, ACYLOXY)
Table 1. (Contd.)
Found, %
H
Calculated, %
H
М
Comp.
Yield, %
no.
mp, °С
Formula
C
N
C
N
9.71
8.04
7.36
6.86
6.03
5.69
5.38
5.38
4.43
4.07
3.07
5.42
4.54
4.16
4.76
4.26
3.86
3.75
8.26
5.64
5.34
6.86
6.42
5.69
5.38
5.11
5.11
4.86
4.34
10.55
5.34
5.07
6.11
found
273.1
340.2
365.0
390.4
451.2
479.5
506.7
508.9
621.0
665.8
901.1
503.4
604.5
660.3
578.8
650.0
613.4
732.9
660.5
483.6
503.7
393.6
420.6
480.4
508.5
539.3
531.5
562.4
632.2
778.0
509.8
542.6
–
calculated
94
95
95
95
94
95
96
95
95
94
96
94
94
94
96
94
95
95
94
94
96
95
94
94
96
94
95
94
95
94
94
95
93
120–121
102–103
116–117
109–110
147–148
74–75
83.49
76.05
69.73
70.86
67.63
68.52
69.45
69.73
72.62
73.51
7.14
7.08
6.52
7.07
6.18
6.62
7.10
7.06
8.35
8.86
9.52 C20H20N2
83.30
75.83
69.46
70.57
67.23
68.28
69.21
69.21
72.12
73.22
6.99
6.94
6.36
6.91
6.08
6.55
6.97
6.97
8.28
8.78
288.4
348.4
380.4
408.5
464.5
492.5
520.6
520.6
632.8
688.9
913.4
516.6
616.7
672.8
588.7
657.5
726.4
746.5
678.7
496.5
524.6
408.5
436.5
492.5
520.6
548.7
548.7
576.7
644.8
796.7
524.5
552.6
(458.5)n
Va
7.86 C22H24N2О2
7.01 C22H24N2О4
6.38 C24H28N2О4
5.74 C26H28N2О6
5.32 C28H32N2О6
5.03 C30H36N2О6
4.97 C30H36N2О6
4.00 C38H52N2О6
3.82 C42H60N2О6
2.90 C58H92N2О6
5.08 C30H32N2О6
4.07 C38H36N2О6
3.88 C42H44N2О6
4.35 C36H32N2О6
3.98 C36H30Сl2N2О6
3.46 C36H28Сl4N2О6
3.34 C36H30Br2N2О6
7.95 C36H30N4О10
5.16 C26H28N2О8
5.04 C28H32N2О8
6.53 C24H28N2О4
6.18 C26H32N2О4
5.34 C28H32N2О6
5.05 C30H36N2О6
4.75 C32H40N2О6
6.81 C32H40N2О6
4.38 C34H44N2О6
4.03 C40H40N2О6
10.02 C38H32N6О14
5.07 C28H32N2О8
4.73 C30H36N2О8
5.62 (С26H22N2O6)n
Vb
Vc
Vd
Ve
Vf
121–122
183–184
106–107
88–89
Vg
Vh
Vi
Vj
65–66
76.15 10.34
76.27 10.15
Vk
Vl
89–90
69.96
74.42
75.20
73.67
66.06
59.88
58.21
64.08
63.17
64.34
70.86
71.85
68.63
69.62
70.39
70.24
71.03
74.87
57.66
64.65
65.45
68.67
6.33
5.99
6.67
5.62
4.74
4.02
4.10
4.53
5.76
6.23
6.96
7.39
6.62
7.14
7.48
7.39
7.77
6.38
4.23
6.28
6.58
5.05
69.75
74.01
74.98
73.45
65.76
59.52
57.93
63.71
62.90
64.11
70.57
71.53
68.28
69.21
70.05
70.05
70.81
74.51
57.29
64.11
65.20
68.11
6.24
5.88
6.59
5.48
4.60
3.88
4.05
4.46
5.68
6.15
6.91
7.39
6.55
6.97
7.35
7.35
7.69
6.25
4.05
6.15
6.57
4.84
124–125
83–84
Vm
Vn
Vo
122–123
78–79
Vpd
Vqe
Vrf
Vs
87–88
106–107
132–133
108–109
96–97
Vt
Vu
VIa
VIb
VIc
VId
VIe
VIf
VIg
VIh
VIi
VIj
VIk
VIIIa
68–69
134–135
71–72
69–70
106–107
118–119
134–135
111–112
122–123
88–89
117–118
>310
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 2 2009

262
DIKUSAR et al.
Table 1. (Contd.)
Found, %
H
Calculated, %
H
М
Comp.
Yield, %
no.
mp, °С
Formula
N
C
C
N
found
calculated
92
96
94
>310
>310
>310
69.70
68.03
69.08
5.54
5.12
(С28H26N2O6)n
(С26H26N2O6)n
(С28H30N2O6)n
69.12
67.52
68.56
5.39
5.67
5.76
6.06
5.76
–
–
–
(486.5)n
(462.5)n
(490.6)n
VIIIb
IXa
6.91
5.73
5.30
6.43
6.16
IXb
a
b
c
Found Сl, %: 10.31. Calculated Cl, %: 10.85. Found Сl, %: 19.30. Calculated Cl, %: 19.63. Found Br, %: 21.10. Calculated Br, %:
21.53. d Found Сl, %: 10.37. Calculated Cl, %: 10.78. e Found Сl, %: 19.16. Calculated Cl, %: 19.52. f Found Br, %: 21.14. Calculated
Br, %: 21.41.
respective structural fragments of ester groups
characteristic of this class compounds [1–3].
PM3 approximation [6] with GAMESS program [7].
All bond lengths, bond and dihedral angles of the
studied compounds were completely optimized. The
following Hf values (kcal mol–1) were obtained: for
Е,Е-isomers, 114.9 (IIIa), –30.7 (IIId), –119.8 (IIIe),
–138.6 (IVd); for E,Z-isomers, 115.1 (IIIa), –30.1
(IIId), –119.1 (IIIe), –137.3 (IVd); for Z,Z-isomers,
115.6 (IIIa), –29.0 (IIId), –118.6 (IIIe), and –136.7
(IVd). From these calculations follows that Е,Е-configura-
tion is by 0.2-1.3 kcal mol–1 is preferable energetically
over E,Z- and by 0.7–1.9 kcal mol–1 over Z,Z-configura-
tion. The calculated Hf (kcal mol–1) values for the respec-
tive diamines are: –74.1 (Va), –72.1 (Vd), –162.7 (Vd),
and –179.5 (VId). Hydrogenation of Е,Е-bis-azome-
thines to diamines leads to incrase in thermodynamic
stability by 40.8–42.9 kcal mol–1. The calculated
energy barriers for the interconfigura-tion E,E-, E,Z-
and Z,Z-transitions are 8–13 kcal mol–1, that allows to
apply the synthesized bis-azomethines as thermo- and
light-sensitive molecular nano-switches [8, 9].
Some of relatively high melting bis-azomethines
(mp above 120°С, see Table 1) showed thermo-
chromic effect owing to reversible transition from E,E-
configuration of bis-azomethine to less thermo-
dynamically advantageous E,Z- and Z,Z-confirgura-
tions that occur before the beginning the crystals of
melting. This process is accompanied by the change in
the form and color of the crystals [1].
For the sudy of the observed thermochromic effect
at the melting of the crystals of azomethines we carried
out quantum-chemical calculations of the heat of
formation (Hf) of E,E-, E,Z- and Z,Z-configuration
isomers of bis-azomethines IIIa, IIId, IIIe, and IVd
and obtained from them secondary diamines Va, Vd,
Ve, and VId. The quantum-chemical calculation were
carried out in the framework of semiempirical MNDO
R
R1
R
R1
R1
R
N
N
N
R
R1
N
N
N
R
R
R1
E, Z
R1
E, E
Z, Z
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 2 2009

263
SYNTHESIS OF N,N'-BIS-[3-ALKOXY-4-(HYDROXY, ALKOXY, ACYLOXY)
60 mmol of glacial acetic acid in 70 ml of absolute
benzene was left at 20–23°С for 5 days with periodical
stirring with magnetic stirrer. The polyamines formed
IXa, IXb were separated by filtration on a porous glass
filter, carefully washed with water, 5% aqueous
NaHCO3, again with water and with some amount of
methanol, and dried in air.
EXPERIMENTAL
The IR spectra were recorded on a Fourier
transform IR spectrometer Protege-460 of Nicolet,
from KBr pellets. The 1Н NMR spectra were recorded
on a BS-587A (100 MHz) Tesla spectrometer from 5%
solutions in CDCl3, chemical shifts were measured
from internal TMS. The elemental analysis was carried
out on a C, H, N, O, S-analyzer Vario EL-III
Elementar, error of determination 0.1%. Molecular
weight was determined by the method of cryoscopy in
benzene.
ACKNOWLEDGMENTS
This work was financially supported by the
Foundation for Bsic Research of Republic Belarus
(grant X 08-227).
Vanillin and vanillal esters I were obtained along
the procedures in [11–14]. For the syntheses was used
1,3-phenylenediamine II of “analytically pure” grade,
purity 99%, mp 62–63°С .
REFERENCES
1. Dikusar, E.A., Kozlov, N.G., Potkin, V.I., Azarko, V.A.,
and Yuvchenko A.P., Zh. Obshch. Khim., 2008, vol. 78,
no. 2, p. 303.
2. Dikusar, E.A., Kozlov, N.G., and Potkin, V.I., Zh.
Obshch. Khim., 2007, vol. 77, no. 11, p. 1871.
3. Dikusar, E.A., Kozlov, N.G., Tlegenov, R.T., and
Uteniyazov, K.U., Azomethines na osnove vanilina and
vanilalya (Azomethines based on Vanillin and Vanillal),
Karakalpakstan: Nukus, 2007.
4. Rao, X., Song, Z., Radbil, B.A., Radbil, A.B., and He, L.,
Abstarct of Papers, Vth All-Russian Scientific Conf.
“Chemistry and Technology of Natural (Vegetable)
Substances,” Ufa, June 8–12, 2008; Syktyvkar-Ufa:
Ross. Akad. Nauk, Ural Branch, 2008, p. 340.
5. Esteves-Souza, A., Echevarria, A., and Sant’Anna, C.M.R.,
Quim. Nova, 2004, vol. 27, no. 1, p. 72.
6. Stewart, J.J.P., J. Comput. Chem., 1989, vol. 10, no. 2,
p. 209.
7. Stewart, J.J.P., J. Comput. Chem., 1989, vol. 10, no. 2,
p. 221.
8. Shmidt, M.W., Baldridge, K.K., Boatz, J.A., Elbert, S.T.,
Gordon, M.S., Jensen, J.H., Koseki, S., Matsunaga, N.,
Nguyen, K.A., Su, S.J., Midus, T.L., Dupnis, M., and
Montgomery, J.A., J. Comput. Chem., 1993, vol. 14, no. 7,
p. 1347.
Е,E-N,N'-bis-[3-Alkoxy-4-(hydroxy-,
alkoxy-,
acyloxy)phenylmethylene]-1,3-phenylenediamines
(IIIa–IIIu, IVa–IVk) (general procedure). A solution
of 10 mmol of a vanillin series aldehyde I and 5 mmol
of 1,3-phenylenediamine II in 50 ml of absolute
methanol was refluxed for 10–15 min. The hot solution
was filtered through a folded paper, cooled and left for
10–15 h at 5°С. The azomethine formed IIIa–IIIu, IVa–
IVk was separated by filtration on a porous glass filter,
washed with a small amount of methanol and dried in
air.
N,N'-bis-[3-Alkoxy-4-(hydroxy-, alkoxy-, acyl-
oxy)phenylmethyl]-1,3-phenylenediamines (Va–Vu,
VIa-VIk) (general procedure). A solution of 5 mmol
of bis-azomethine IIIa–IIIu , IVa–IVk, 20 mmol of
NaBH4, 60 mmol of glacial acetic acid in 70 ml of
absolute benzene was left for 18–20 h at 20–23°С .
The solution formed was washed with water and 5%
aqueous NaHCO3 and solvent was removed in a
vacuum. The residue was purified by recrystallization
from benzene – hexane mixture.
Е,Е-poly-[3-Alkoxy-4-succinyloxyphenylmethylene]-
1,3-phenylenediamines (VIIIa, VIIIb). A solution of
5 mmol of vanillin or vanillal succinate VIIa, VIIb
and 5 mmol of 1,3-phenylenediamine II in 50 ml of
1:1 mixture of absolute methanol and chloroform was
refluxed for 30 min. The hot solution was cooled and
azomethine VIIIa, VIIIb was separated by filtration
on porous glass filter, washed with small amount of
methanol and dried in air.
9. Hadjoudis, E. and Maveidis, I.M., Chem. Soc. Rev.,
2004, vol. 33, no. 9, p. 579.
10. Liu, Bo, Hu, Xue-Lei, Liu, Jun, Zhao, Yuan-Di, and
Huang, Zhen-Li., Tetrahedron Lett., 2007, vol. 48, no. 24,
p. 5958.
11. Dikusar, E.A., Vyglazov, O.G., Moiseichuk, K.L.,
Zhukovskaya, N.A., and Kozlov, N.G., Zh. Prikl. Khim.,
2005, vol. 78, no. 1, p. 122.
12. Dikusar, E.A. and Kozlov, N.G., Khim. Ppromyshl.,
2005, no. 1, p. 74.
13. Dikusar, E.A. and Kozlov, N.G., Zh. Org. Khim., 2005,
vol. 41, no. 7, p. 1015.
Poly-[3-Alkoxy-4-succinyloxyphenylmethyl]-1,3-
phenylenediamines (IXa, IXb). A suspension of 5 mmol
of polyazomethine VIIIa, VIIIb, 20 mmol of NaBH4,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 2 2009