Synthesis of chiral azomethines starting from L-valine methyl ester hydrochloride and substituted benzaldehydes of vanillin series

Article abstract of DOI:10.1134/S1070428010050076

A preparative method of synthesis of chiral azomethines was developed consisting in the reaction of L-valine methyl ester hydrochloride reaction with substituted benzaldehydes of vanillin series. Pleiades Publishing, Ltd., 2010.

Full text of DOI:10.1134/S1070428010050076

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2010, Vol. 46, No. 5, pp. 644−648. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © E.A. Dikusar, V.I. Potkin, N.A. Zhukovskaya, 2010, published in Zhurnal Organicheskoi Khimii, 2010, Vol. 46, No. 5, pp. 655−
659.
Synthesis of ChiralAzomethines Starting
from L-Valine Methyl Ester Hydrochloride
and Substituted Benzaldehydes of Vanillin Series
E. A. Dikusar, V. I. Potkin, and N. A. Zhukovskaya
Institute of Pysical Organic Chemistry, National Academy of Sciences of Belarus, Minsk, 220072 Belarus
e-mail: evgen_58@mail.ru
Received June 9, 2009
Abstract—A preparative method of synthesis of chiral azomethines was developed consisting in the reaction of
L-valine methyl ester hydrochloride reaction with substituted benzaldehydes of vanillin series.
DOI: 10.1134/S1070428010050076
L-Valine methyl ester hydrochloride (I) may serve
as a con-venient and available synthon for the synthesis
of chiral nitrogen-containing organic compounds [1–3].
Many among the derivatives of natural amino acids
derivatives , in particular, of N-[O-(C)-carboranyl]alanine,
exhibit high antibacterial and antitumor action [4].
the presence of sodium hydrogen carbonate (at the
stoichiometric reagents ratio 1:1:1) afforded new chiral
alkylaromatic azomethines (Schiff bases) containing ether
and ester groups IIIa–IIIx, IVa–IVn, V, VIa, VIb. The
condensation was carried out at boiling the mixture of
initial reagents in anhydrous methanol for 30–45 min. Chiral
alkylaromatic azomethines IIIa–IIIx, IVa–IVn, V, VIa,
VIb were obtained in preparative yields 78–89%.
The condensation of L-valine methyl ester
hydrochloride (I) with substituted benzaldehydes II in
HC N CHCHMe2
CHO
HC N CHCHMe2
CO2Me
CO2Me
CO2Me
R
NaHCO3
NaCl
+
CHCHMe2
N CHCHMe2
CO2Me
HC
.
R
R
NH2 HCl
R'
II
R'
IIIa_IIIx, IVa_IVn
V, VIa, VIb
I
R = 4,4'-C6H4C6H4 (V);
III, R = R’ = H (a); R = H, R' = MeO (b); R = MeO, R' = HO
(c), MeO (d), MeC(O)O (e), EtC(O)O (f), PrC(O)O (g),
Me2CHC(O)O (h), BuC(O)O (i), Me2CHCH2C(O)O (j),
Me(CH2)6C(O)O (k), Me(CH2)8C(O)O (l),
Me(CH2)16C(O)O (m), H2C=C(Me)C(O)O (n),
C6H5CH(Με)CH2C(O)O (o), C6H5C(O)O (p), 2,4-
Cl2C6H3C(O)O (q), 4-BrC6H4C(O)O (r), 3-O2NC6H4C(O)O
(s), MeOC(O)O (t), EtOC(O)O (u), 1-AdC(O)O (v), o-
HCB10H10CC(O)O (w), m-HCB10H10CC(O)O (x); IV, R =
EtO, R’ = HO (a), MeO (b), MeC(O)O (c), EtC(O)O (d),
PrC(O)O (e), Me2CHC(O)O (f), BuC(O)O (g),
Me2CHCH2C(O)O (h), 4-MeC6H4C(O)O(i), MeOC(O)O
(j), EtOC(O)O (k), 1-AdC(O)O (l), o-HCB10H10CC(O)O
(m), m-HCB10H10CC(O)O (n).
R =
OR'
R'O
OC(O)CH2CH2C(O)O
R' = Me (VIa), Et (VIb).
The obtained azomethines IIIa–IIIx, IVa–IVn, V,
VIa, VIb are colorless or weakly colored thick oily fluids
or crystalline substances, they do not require additional
purification and are free of impurities of the initial
compounds. The composition and structure of azomethines
644

SYNTHESIS OF CHIRAL AZOMETHINES
645
IIIa–IIIx, IVa–IVn, V, VIa, VIb were proved by IR,
UV, 1H NMR spectra, elemental analysis, and cryoscopic
measurement of the molecular weight. According to
1H NMR spectra the purity of compounds obtained
reached 94 ± 2%.
or in KBr pellets, UV spectra, on spectrophotometer
Specord UV Vis from 1 × 10–4 Μ solution of compounds
in methanol, 1H NMR spectra were registered on a spec-
trometer Tesla BS-587A (100 ΜHz) from 5% solutions
in deuterochloroform or DMSO-d6, intertnal reference
TMS. The specific rotation was measured on a CM-2
instrument from 5% solutions of substances in methanol.
Elemental analyses were carried out on a C,H,N,O,S-
analyzer Elementar Vario EL-III, accuracy of the
measurements 0.1%. The molecular weights were
determined by cryoscopy in benzene.
In the IR spectra of azomethines IIIa–IIIx, IVa–
IVn, V, VIa, VIb the following characteristic
absorption bands were observed, ν, cm–1: 3080–
3000, 870–620 (CHarom), 2995–2825 (CHaliph), 1770–
1739 (C=Oester) (IIIe–IIIx, IVc–IVn, VIa, VIb);
1643–1637 (C=N), 1607–1417 (C=Carom), 1270–1033
(C–O) cm–1. In the IR spectrum of compound IIIs the
presence of NO2 group was confirmed by the
characteristic absorption bands in the region 1531 and
1348 cm–1. In the IR spectra of carborane-containing
azomethines IIIw, IIIx, IVv, IVn the absorption bands
of C–Hcarborane appeared at 3070 (IIIw, IVm) and 3032
(IIIx, IVn); of B–H, at 2680–2660 cm–1.
L-Valine methyl ester hydrochloride (I) used in the
research was of “pure for analysis” grade (purity 98%),
mp 171–172°C, [α]D20 +23.4°. Vanillin and vanillal esters
II were obtained by procedures [7–12].
Chiral alkylaromatic azomethins containing ether
and ester groups IIIa–IIIx, IVa–IVn. A mixture
of 5 mmol of L-valine methyl ester hydrochloride (I),
5 mmol of substituted benzaldehyde II, and 5 mmol of
sodium hydrogen carbonate in 39 ml of anhydrous
methanol was boiled for 30–45 min. The hot solution was
filtered through a folded paper filter, the solvent was
removed in a vacuum.Azomethines IIIa–IIIx, IVa–IVn
were dissolved in 10 ml of anhydrous ethyl ether, the
solution was filtered through a folded paper filter, the
solvent was removed in a vacuum. The final purification
was performed by column chromatography on neutral
aluminum oxide, 40–100 μm, II grade Brockmann activity,
eluent dichloromethane.
In the UV spectra of compounds IIIe–IIIx, IVc–
IVn, VIa, VIb characteristic absorption maxima are
observed at λmax, nm (å): 208 (13000), 220 (13000), 254
(9000), 300 (400) due to the presence in these molecules
of the fragments of methyl (Ε,S)-2-(4-acyloxy-3-
alkoxybenzylideneamino)-3-methybutyrate.
The 1H NMR spectra of azomethines IIIa–IIIx, IVa–
IVn, V, VIa, VIb contain the signals of protons from
Me2C group as two doublets in the region 0.80–1.10 ppm,
signals of CHaliph as two multiplets in the region 2.15–
2.60 and 3.30–3.70 ppm, signals of CO2Me as a singlet
1
in the range 3.65–3.75 ppm. In the H NMR spectra of
azomethines IIIb–IIIx, IVb, VIa the signals of MeO
group appear as a singlet in the range 3.74–3.80 ppm, in
the spectra of compounds IVa–IVn, VIb the protons of
EtO groups give rise to a triplet in the range 0.90–1.30
ppm (Me) and a quartet at 3.80–4.20 ppm (CH2). The
signals of the aromatic protons in the spectra of
compounds IIIa–IIIx, IVa–IVn, V, VIa, VIb are
observed in the region 6.80–7.50 ppm, the protons of the
azomethine group HC=N appear as a singlet in the region
8.11– 8.22 ppm characteristic of (Ε)- azomethines [5].
In the IR, UV, and 1H NMR spectra of azomethines
IIIa–IIIx, IVa–IVn, V, VIa, VIb the appropriate
absorption bands and proton signals prove the presence
of the structural fragments of ester groups [6].
Methyl (Ε,S)-2-benzylideneamino-3-methyl-
20
butyrate (IIIa). Yield 84%, d 1.2630, nD20 1.5212, [α]D20
20
–41.1°. Found, %: C 71.54; H 7.88; N 6.12. M 210.4.
C13H17NO2. Calculated, %: C 71.21; H 7.81; N 6.39.
M 219.3.
Methyl (Ε,S)-3-methyl-2-(4-methoxybenz-
20
ylideneamino)-butyrate (IIIb). Yield 88%, d 1.2801,
20
nD20 1.5296, [α]D20 –50.4°. Found, %: C 67.59; H 7.83;
N 5.36. M 235.2. C14H19NO3. Calculated, %: C 67.45;
H 7.68; N 5.62. M 249.3.
Methyl (Ε,S)-2-(4-hydroxy-3-methoxy-benz-
ylideneamino)-3-methylbutyrate (IIIc). Yield 78%,
20
d
1.2864, nD20 1.5568, [α]D20 –38.5°. Found, %: C 63.52;
20
H 7.29; N 4.93. M 252.7. C14H19NO4. Calculated, %:
C 63.38; H 7.22; N 5.28. M 265.3.
EXPERIMENTAL
Methyl (Ε,S)-2-(3,4-dimethoxybenzylidene-
20
IR spectra of compounds were recorded on FTIR
spectrophotometer Nicolet Protege-460 from thin films
amino)-3-methylbutyrate (IIId). Yield 89%, d 1.2814,
20
nD20 1.5338, [α]D20 –36.8°. Found, %: C 64.80; H 7.64;
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 46 No. 5 2010

DIKUSAR et al.
646
Calculated, %: C 71.91; H 9.93; N 2.71. M 517.7.
N 4.85. M 270.5. C15H21NO4. Calculated, %: C 64.50;
H 7.58; N 5.01. M 279.3.
Methyl (Ε,S)-2-(4-methacryloyloxy-3-methoxy-
benzylideneamino)-3-methylbutyrate (IIIn). Yield
Methyl (Ε,S)-2-(4-acetyloxy-3-methoxybenzylid-
20
84%, d 1.210, nD20 1.5130, [[α]D20 –30.3°. Found, %:
eneamino)-3-methylbutyrate (IIIe). Yield 85%,
20
20
d
1.2410, nD20 1.5192, [α]D20 –32.7°. Found, %: C 62.53;
C 65.14; H 7.08; N 4.13. M 324.8. C18H23NO5.
20
Calculated, %: C 64.85; H 6.95; N 4.20. M 333.4.
H 6.89; N 4.56. M 299.6. C16H21NO5. Calculated, %:
C 62.53; H 6.89; N 4.56. M 307.3.
Methyl (Ε,S)-3-methyl-2-[3-methoxy-4-(3-
phenyl-butyryloxy)benzylideneamino]-butyrate
Methyl (Ε,S)-3-methyl-2-(3-methoxy-4-propion-
20
(IIIo). Yield 84%, d 1.2303, nD20 1.5352, [α]D20 –21.8°.
yloxybenzylideneamino)butyrate (IIIf). Yield 88%,
20
20
d
1.2365, nD20 1.5198, [α]D20 –31.0°. Found, %: C 63.86;
Found, %: C 70.26; H 7.25; N 3.06. M 401.2.
20
C24H29NO5. Calculated, %: C 70.05; H 7.10; N 3.40.
M 411.5.
H 7.35; N 4.07. M 314.8. C17H23NO5. Calculated, %:
C 63.54; H 7.21; N 4.36. M 321.4.
Methyl (Ε,S)-2-(4-benzoyloxy-3-methoxybenzyl-
ideneamino)-3-methylbutyrate (IIIp). Yield
Methyl (Ε,S)-2-(4-butyryloxy-3-methoxybenzyl-
ideneamino)-3-methylbutyrate (IIIg). Yield 88%,
20
89%, d 1.2415, nD20 1.5512, [α]D20 –25.3°. Found, %:
20
d
1.2280, nD20 1.5084, [α]D20 –27.2°. Found, %: C 64.72;
20
20
C 68.47; H 6.38; N 3.37. M 355.7. C21H23NO5.
Calculated, %: C 68.28; H 6.28; N 3.79. M 369.4.
H 7.68; N 3.85. M 321.0. C18H25NO5. Calculated, %:
C 64.46; H 7.51; N 4.18. M 335.4.
Methyl (Ε,S)-2-[4-(2,4-dichlorobenzoyloxy)-3-
Methyl (Ε,S)-2-(4-isobutyryloxy-3-methoxybenz-
ylidene-amino)-3-methylbutyrate (IIIh). Yield
methoxy-benzylideneamino]-3-methylbutyrate
20
(IIIq). Yield 83%, d 1.3419, nD20 1.5578, [α]D20 –20.6°.
20
82%, d 1.2212, nD20 1.4988, [α]D20 –25.9°. Found, %:
20
20
Found, %: C 57.84; H 4.82; Cl 15.85; N 2.93. M 419.1.
C 64.58; H 7.60; N 3.89. M 322.4. C18H25NO5.
C21H21Cl2NO5. Calculated, %: C 57.55; H 4.83; Cl 16.18;
Calculated, %: C 64.46; H 7.51; N 4.18. M 335.4.
N 3.20. M 438.3.
Methyl (Ε,S)-2-(4-valeroyloxy-3-methoxybenzyl-
20
Methyl (Ε,S)-2-[4-(4-bromobenzoyloxy)-3-
ideneamino)-3-methylbutyrate (IIIi). Yield 85%, d
20
1.1840, nD20 1.5125, [α]D20 –24.6°. Found, %: C 65.70;
H 7.85; N 3.80. M 334.3. C19H27NO5. Calculated, %:
C 65.31; H 7.79; N 4.01. M 349.4.
methoxy-benzylideneamino]-3-methyl-butyrate
(IIIr). Yield 85%, d 1.3503, nD20 1.5668, [α]D20 –21.4°.
20
20
Found, %: C 56.61; H 5.07; Br 17.36; N 2.90. M 425.8.
C21H22BrNO5. Calculated, %: C 56.26; H 4.95; Br 17.82;
N 3.12. M 448.3.
Methyl
(Ε,S)-2-(4-isovaleroyloxy-3-
methoxybenz-ylideneamino)-3-methylbutyrate
(IIIj). Yield 84%, d 1.1748, nD20 1.4926, [α]D20 –25.2°.
20
Methyl (Ε,S)-3-methyl-2-[-3-methoxy-4-(3-nitro-
benzoyl-oxy)benzylideneamino]butyrate (IIIs). Yield
80%, mp 73–74°C, [α]D20 –19.7°. Found, %: C 61.11;
H 5.38; N 6.43. M 402.6. C21H22N2O7. Calculated, %: C
60.86; H 5.35; N 6.76. M 414.4.
20
Found, %: C 65.76; H 7.92; N 3.82. M 335.1.
C19H27NO5. Calculated, %: C 65.31; H 7.79; N 4.01.
M 349.4.
Methyl (Ε,S)-2-(4-capryloyloxy-3-methoxybenz-
ylideneamino)-3-methylbutyrate (IIIk). Yield 81%,
Methyl (Ε,S)-3-methyl-2-(4-methoxycarbonyl-
20
d
1.1730, nD20 1.4944, [α]D20 –22.3°. Found, %: C 67.12;
oxy-3-methoxybenzylideneamino)butyrate
20
20
(IIIt). Yield 79%, d 1.2246, nD20 1.5065, [α]D20 –32.5°.
H 8.34; N 3.46. M 368.2. C21H31NO5. Calculated, %:
C 66.82; H 8.28; N 3.71. M 377.5.
20
Found, %: C 59.84; H 6.70; N 4.02. M 316.5.
C16H21NO6. Calculated, %: C 59.43; H 6.55; N 4.33;
M 323.3.
Methyl (Ε,S)-2-(4-decanoyloxy-3-methoxybenz-
20
ylideneamino)-3-methylbutyrate (IIIl). Yield 83%, d
20
1.1645, nD20 1.4972, [α]D20 –21.7°. Found, %: C 68.37;
Methyl (Ε,S)-3-methyl-2-(-3-methoxy-4-ethoxy-
H 8.82; N 3.18. M 389.5. C23H35NO5. Calculated, %:
C 68.12; H 8.70; N 3.45. M 405.5.
carbonyloxybenzylideneamino)butyrate (IIIu).
20
Yield 82%, d 1.2204, nD20 1.5048, [α]D20 –30.4°.
20
Found, %: C 60.88; H 6.94; N 3.81. M 322.0.
Methyl
(Ε,S)-3-methyl-2-(3-methoxy-4-
C17H23NO6. Calculated, %: C 60.52; H 6.87; N 4.15.
M 337.4.
stearoyloxy-benzylideneamino)butyrate (IIIm).
Yield 80%, mp 37–38°C (methanol), [α]D20 –17.4°. Found,
%: C 72.23; H 10.07; N 2.49. M 501.6. C31H51NO5.
Methyl (Ε,S)-2-[4-(1-adamantanemethanoyloxy)-
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 46 No. 5 2010

SYNTHESIS OF CHIRAL AZOMETHINES
647
idene-amino)-3-methylbutyrate (IVg). Yield
3-methoxybenzylideneamino]-3-methylbutyrate
(IIIv). Yield 88%, mp 60–61°C, [α]D20 –26.6°. Found,
%: C 70.56; H 7.99; N 2.97. M 412.5. C25H33NO5.
Calculated, %: C 70.23; H 7.78; N 3.28. M 427.5.
20
86%, d 1.1817, nD20 1.5170, [α]D20 –25.6°. Found, %:
20
C 66.36; H 8.27; N 3.61. M 349.5. C20H29NO5.
Calculated, %: C 66.09; H 8.04; N 3.85. M 363.4.
Methyl (Ε,S)-2-(4-isovaleroyloxy-3-ethoxybenz-
ylidene-amino)-3-methylbutyrate (IVh). Yield
Methyl (Ε,S)-2-[4-(O-carborane-C-methanoyl-
oxy)-3-methoxybenzylideneamino]-3-methyl-
butyrate (IIIw). Yield 83%, mp 76–77°C, [α]D20 –21.7°.
Found, %: C 48.25; H 4.52; Β 25.12; N 2.93. M 405.6.
C17H19Β10NO5. Calculated, %: C 47.99; H 4.50; Β 25.41;
N 3.29. M 425.4.
20
85%, d 1.1714, nD20 1.5028, [α]D20 –24.8°. Found, %:
20
C 66.31; H 8.20; N 3.52. M 351.6. C20H29NO5.
Calculated, %: C 66.09; H 8.04; N 3.85. M 363.4.
Methyl (Ε,S)-3-methyl-2-[4-(4-methyl-benzoyl-
oxy)-3-ethoxybenzylideneamino]butyrate (IVi). Yield
Methyl (Ε,S)-2-[4-(μ-carborane-C-methanoyl-
oxy)-3-methoxybenzylideneamino]-3-methyl-
butyrate (IIIx). Yield 80%, mp 85–86°C, [α]D20 –22.5
[α]D20. Found, %: C 48.34; H 4.59; Β 25.02; N 2.98.
M 410.2. C17H19Β10NO5. Calculated, %: C47.99; H 4.50;
Β 25.41; N 3.29. M 425.4.
20
85%, d 1.2226, nD20 1.5490, [α]D20 –20.3°. Found, %:
20
C 69.64; H 6.97; N 3.19. M 385.8. C23H27NO5.
Calculated, %: C 69.50; H 6.85; N 3.52. M 397.5.
Methyl (Ε,S)-2-{[4-(methoxycarbonyl)oxy]-3-
ethoxybenzylideneamino}-3-methylbutyrate (IVj).
20
Yield 80%, d 1.2208, nD20 1.5090, [α]D20 –34.8°. Found,
20
Methyl (Ε,S)-2-(4-hydroxy-3-ethoxy-benzyl-
%: C 60.80; H 6.99; N 3.92. M 328.3. C17H23NO6.
Calculated, %: C 60.52; H 6.87; N 4.15. M 337.4.
ideneamino)-3-methylbutyrate (IVa). Yield 80%,
20
d
1.2835, nD20 1.5362, [α]D20 –36.5°. Found, %: C 64.57;
20
Methyl (Ε,S)-3-methyl-2-(3-ethoxy-4-ethoxy-
carbonyl-oxybenzylideneamino)butyrate (IVk). Yield
H 7.66; N 4.82. M 265.4. C15H21NO4. Calculated, %:
C 64.50; H 7.58; N 5.01. M 279.3.
20
82%, d 1.2168, nD20 1.5060, [α]D20 –32.5°. Found, %:
20
Methyl (Ε,S)-3-methyl-2-(4-methoxy-3-ethoxy-
C 61.87; H 7.23; N 3.76. M 337.4. C18H25NO6.
Calculated, %: C 61.52; H 7.17; N 3.99. M 351.4.
20
benzylideneamino)butyrate (IVb). Yield 83%, d
20
1.2663, nD20 1.5255, [α]D20 –38.1°. Found, %: C 65.70;
H 8.00; N 4.34. M 281.4. C16H23NO4. Calculated, %:
C 65.51; H 7.90; N 4.77. M 293.4.
Methyl (Ε,S)-2-[4-(1-adamantanemethanoyloxy)-
3-ethoxybenzylideneamino]-3-methylbutyrate (IVl).
20
Yield 86%, d 1.2658, nD20 1.5280, [α]D20 –21.0°. Found,
20
Methyl (Ε,S)-2-(4-acetyloxy-3-ethoxybenz-
ylideneamino)-3-methylbutyrate (IVc). Yield 88%,
%: C 70.93; H 8.13; N 2.90. M 428.7. C26H35NO5.
Calculated, %: C 70.72; H 7.99; N 3.17. M 441.6.
20
d
1.2370, nD20 1.5208, [α]D20 –37.2°. Found, %: C 63.80;
20
Methyl (Ε,S)-2-[4-(O-carborane-C-methanoyl-
oxy)-3-ethoxybenzylideneamino]-3-methylbutyrate
(IVm). Yield 80%, mp 70–71°C, [α]D20 –19.7°. Found,
%: C 49.46; H 5.06; Β 24.18; N 2.90. M 418.7.
C18H21Β10NO5. Calculated, %: C 49.19; H 4.82; Β 24.60;
N 3.19. M 439.5.
H 7.32; N 4.02. M 313.2. C17H23NO5. Calculated, %:
C 63.54; H 7.21; N 4.36. M 321.4.
Methyl (Ε,S)-3-methyl-2-(4-propionyloxy-3-oxy-
benzylideneamino)butyrate (IVd). Yield 87%,
20
d
1.2342, nD20 1.5036, [α]D20 –36.8°. Found, %: C 64.67;
20
H 7.68; N 3.95. M 362.3. C18H25NO5. Calculated, %:
C 64.46; H 7.51; N 4.18. M 335.4.
Methyl (Ε,S)-2-[4-(m-carborane-C-methanoyl-
oxy)-3-ethoxybenzylideneamino]-3-methylbutyrate
(IVn). Yield 81%, mp 79–80°C, [α]D20 –19.1°. Found, %:
C 49.50; H 5.03; Β 24.11; N 2.92. M 422.3.
C18H21Β10NO5. Calculated, %: C 49.19; H 4.82; Β 24.60;
N 3.19. M 439.5.
Methyl (Ε,S)-2-(4-butyryloxy-3-ethoxybenzyl-
ideneamino)-3-methylbutyrate (IVe). Yield 82%,
20
d
1.2235, nD20 1.5070, [α]D20 –34.0°. Found, %: C 65.67;
20
H 7.86; N 3.83. M 335.3. C19H27NO5. Calculated, %:
C 65.31; H 7.79; N 4.01. M 349.4.
Diazomethines V, VIa, VIb were obtained and
isolated analogously to compounds IIIa–IIIx, IVa–IVn.
A mixture of 10 mmol of compound I, 5 of dialdehyde,
and 10 mmol of sodium hydrogen carbonate in 50 ml of
anhydrous methanol was boiled for 45 min.
Methyl (Ε,S)-2-(4-isobutyryloxy-3-ethoxy-
benzylidene-amino)-3-methylbutyrate (IVf).
20
Yield 86%, d 1.2206, nD20 1.5012, [α]D20 –27.5°. Found,
20
%: C 65.63; H 7.82; N 3.80. M 339.4. C19H27NO5.
Calculated, %: C 65.31; H 7.79; N 4.01. M 349.4.
Methyl (Ε,S)-2-(4-valeroyloxy-3-ethoxybenzyl-
Dimethyl (S,S)-2,2'-{biphenyl-4,4'-diylbis[(E)-
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 46 No. 5 2010

DIKUSAR et al.
648
methylidenenitrilo]}-3,3'-dimethyldibutanoate
(V). Yield 84%, mp 124–125°C, [α]D20 –62.6°. Found,
%: C 71.69; H 7.52; N 6.14. M 415.9. C26H32N2O4.
Calculated, %: C 71.53; H 7.39; N 6.42. M 436.5.
4. Oros, G., Ujvary, I., and Nachman, R.J., Amino Acids, 1999,
vol. 17, p. 357.
5. Daier, D.R., Prilozheniya absorbtsionnoi spektroskopii
organicheskikh soedinenii (Applications of Absorption
Spectroscopy of Organic Copmounds), Moscow: Khimiya,
1970.
6. Dikusar, E.A., Kozlov, N.G., Tlegenov, R.T., and Uteniya-
zov, K., Azometiny na osnove vanilina i vanilalya
(Azomethines on the Basis of Vaniline and Valile), Nukus:
“Karakalpakstan, ” 2007, 207.
7. Dikusar, E.A., Vyglazov, O.G., Moiseichuk, K.L.,
Zhukovskaya, N.A., and Kozlov, N.G., Zh. Prikl. Khim.,
2005, vol. 78, p. 122.
Di[2-methoxy-4-(E,S)-(2-methyl-1-methoxy-
carbonyl-propyliminomethyl)phenyl]succinate (VIa).
Yield 87%, mp 67–68°C, [α]D20 –40.3°. Found, %: C 62.95;
H 6.59; N 4.18. M 598.2. C32H40N2O10. Calculated, %:
C 62.73; H 6.58; N 4.57. M 612.7.
Di[4-(Ε,S)-(2-methyl-1-methoxycarbonyl-
propyliminomethyl)-2-ethoxyphenyl]succinate
(VIb). Yield 83%, mp 62–63°C, [α]D20 –39.1°. Found, %:
C 64.16; H 7.08; N 4.05. M 618.5. C34H44N2O10.
Calculated, %: C 63.74; H 6.92; N 4.37. M 640.7.
8. Dikusar, E.A.and Kozlov, N.G. , Khim. Polim. Soedin., 2005,
p. 74.
9. Dikusar, E.A., Kozlov, N.G., Zh. Org. Khim., 2005, vol. 41,
p. 1015.
REFERENCES
10. Dikusar, E.A., Zh. Prikl. Khim., 2006, vol. 79, p. 1043.
11. Dikusar, E.A., Kozlov, N.G., Potkin, V.I., Zvereva, T.D.,
Yuvchenko, A.P., Bei, M.P., and Kovganko, N.V., Khim.
Polim. Soedin., 2006, p. 434.
12. Dikusar, E.A., Potkin, V.I., Kozlov, N.G., Yuvchenko,A.P.,
Bei, M.P., and Kovganko, N.V., Zh. Org. Khim., 2008,
vol . 44, p. 1321.
1. Meierhenrich, U.J., Amino Acids and the Asymmetry of
Life, Berlin: Springer-Verlag, 2008.
2. Barrett, G.C., Amino Acid Derivatives:A Practical Approach
(Practical Approach Series), Oxford University Press, 2000.
3. Paquette, L.A., Handbook of Reagents for Organic
Synthesis Chiral Reagents for Asymmetric Synthesis, New
York: Wiley, 2003, p. 582.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 46 No. 5 2010