Spirocyclohexadienones: X. Three-component condesation of 1,2,3- and 1,2,4-trimethoxybenzenes with cyclohexanecarbaldehyde and nitriles. Synthesis of 1,2- and 1,4-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4-dien-3-ones

Article abstract of DOI:10.1134/S1070428009030038

Substituted 1,2- and 1,4-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4- dien-3-ones and 1,2(1,4)-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4,14-trien- 3-ones were synthesized by three-component condensation of cyclohexanecarbaldehyde with 1,2,3- or 1,2,

Full text of DOI:10.1134/S1070428009030038

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2009, Vol. 45, No. 3, pp. 360–364. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © I.V. Plekhanova, O.G. Stryapunina, V.A. Glushkov, V.I. Karmanov, O.A. Maiorova, Yu.V. Shklyaev, 2009, published in Zhurnal
Organicheskoi Khimii, 2009, Vol. 45, No. 3, pp. 372–376.
Spirocyclohexadienones: X.* Three-Component Condesation
of 1,2,3- and 1,2,4-Trimethoxybenzenes with Cyclohexanecarbal-
dehyde and Nitriles. Synthesis of 1,2- and 1,4-Dimethoxy-
14-azadispiro[5.1.5.2]pentadeca-1,4-dien-3-ones
I. V. Plekhanova, O. G. Stryapunina, V. A. Glushkov, V. I. Karmanov,
O. A. Maiorova, and Yu. V. Shklyaev
Institute of Technical Chemistry, Ural Division, Russian Academy of Sciences,
ul. Akademika Koroleva 3, Perm, 614990 Russia
e-mail: glusha@nm.ru
Received April 30, 2008
Abstract—Substituted 1,2- and 1,4-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4-dien-3-ones and
1,2(1,4)-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4,14-trien-3-ones were synthesized by three-component
condensation of cyclohexanecarbaldehyde with 1,2,3- or 1,2,4-trimethoxybenzene and the corresponding
nitriles in the presence of concentrated sulfuric acid.
DOI: 10.1134/S1070428009030038
In the recent years interest in the synthesis of
heterocyclic systems from aromatic precursors has in-
creased considerably. We have developed a procedure
for dearomatization of substituted arenes via three-
component condensation with α-branched aldehydes
and nitriles which ensured one-step preparation of
2-azaspiro[4.5]decanes. Some 2-azaspiro[4.5]decane
derivatives were found in the nature; examples are
antibiotic spirostaphylotrichin [2] and alkaloid anno-
squaline [3]. Among synthetic 2-azaspiro[4.5]decane
derivatives, HIV-1 protease inhibitors [4] and com-
pounds possessing anticarcinogenic [5], antiarthritic
[6], and antigastric properties [7] were reported. In
some cases 2-azaspiro[4.5]decanes are formed as inter-
mediates in cyclizations and recyclizations of iso-
quinolines [8, 9]. Classical synthetic approaches to
2-azaspiro[4.5]decanes include radical cyclizations of
haloacetamides [10, 11], N-allyl amides [12], and di-
thiocarbonates [13] and intramolecular Heck reactions
[14]. In the recent time, new effective spirocyclization
procedures have been reported, such as olefin meta-
thesis [15], intramolecular cascade cyclization of
iminium [16] and thionium salts [17], dearomatization
of arene ruthenium complexes [18–23], and cyclization
of diene iron complexes [24–26].
We previously proposed a procedure for the syn-
thesis of 2-azaspiro[4.5]decane derivatives by three-
component condensation of anisole [27] or m-xylene
[28] with isobutyraldehyde and nitriles in the presence
of concentrated sulfuric acid. With a few exceptions
[29, 30], no data on analogous reactions with cyclo-
hexanecarbaldehyde have been reported, although such
reactions should obviously lead to the formation of
dispiro compounds some of which were prepared by us
previously by linear syntheses [31].
The goal of the present work was to examine the
behavior of cyclohexanecarbaldehyde in three-com-
ponent condensation of 1,2,3- and 1,2,4-trimethoxy-
benzenes with some nitriles. In the first step of our
study, 1,2,3-trimethoxybenzene was reacted with cy-
clohexanecarbaldehyde and cyanoacetic acid esters in
the presence of concentrated sulfuric acid (Scheme 1).
As a result, we isolated the corresponding dispiro com-
pounds, substituted 14-azadispiro[5.1.5.2]pentadeca-
1,4-dien-3-ones Ia and Ib, whose structure was con-
1
firmed by IR and H NMR spectroscopy. Compound
1
Ia displayed in the H NMR spectrum signals from
three methoxy groups at δ 3.57, 3.69, and 3.99 ppm.
1
In the H NMR spectrum of Ib we observed a set
of signals typical of ester ethoxy group (a triplet at
* For communication IX, see [1].
δ 1.12 ppm and a multiplet at δ 3.96 ppm due to CH3
360

SPIROCYCLOHEXADIENONES: X.
361
Scheme 1.
OMe
OMe
MeO
O
OMe
OMe
CHO
H2SO4
N
NC
+
+
OR
MeO
COOR
A
11
10
12
9
13
8
OMe
OMe
OMe
14
N
15
1
7
MeO
MeO
MeO
MeO
MeO
O
2
N
N
H
H
H
6
·
·
·
–MeOH
·
·
·
3
·
·
·
O
O
5
O
4
HO
H2O
OR
OR
OR
B
C
Ia, Ib
R = Me (a), Et (b).
and OCH2 protons, respectively). The IR spectra of
Ia and Ib contained absorption bands belonging to
stretching vibrations of NH and C=O groups (3320 and
1652–1660 cm–1, respectively); the latter was dis-
placed toward lower frequencies due to formation of
intramolecular hydrogen bond, as we observed previ-
ously for spiro compounds obtained from anisole [27].
Compounds Ia and Ib were isolated as mixtures of
enantiomers with respect to the C6 spiro-carbon atom;
as a result, diastereotopic methylene protons on C7 had
different chemical shifts, and their signals were split
into doublets (2J = 13.5–13.8 Hz).
Analogous condensation was performed using
1,2,4-trimethoxybenzene as aromatic component. The
reaction followed a similar path (Scheme 2) and result-
ed in the formation of dispiro compounds IIa and IIb.
Like compounds Ia and Ib, 1,4-dimethoxy derivatives
1
IIa and IIb had enamine structure. Their H NMR
spectra contained a singlet at δ 3.91–3.93 ppm from
the olefinic proton (C15=CH) and a broadened NH
Scheme 2.
OMe
OMe
O
OMe
CHO
H2SO4
N
NC
+
+
OR
MeO
MeO
MeO
COOR
A
OMe
OMe
OMe
N
N
N
H
H
H
·
·
·
–MeOH
·
·
·
·
·
·
HO
MeO
O
O
O
MeO
H2O
O
OMe
OMe
OMe
IIa, IIb
OR
OR
OR
B
C
R = Me (a), Et (b).
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 3 2009

PLEKHANOVA et al.
362
Scheme 3.
R1
CHO
+
+ PhCN
MeO
R3
R2
R1
11
12
10
9
R1
8
N14
5
7
1
H2SO4
N
4
6
15
R3
MeO
–MeOH
3
R2
Ph
Ph
R3
O
2
R2
A
IIIa–IIIc
R1 = H, R2 = R3 = MeO (a); R1 = R2 = MeO, R3 = H (b); R1 = R3 = MeO, R2 = H (c).
singlet at δ 8.37 ppm. In the IR spectra of IIa and IIb,
NH absorption bands appeared at 3320–3330 cm–1,
stretching vibrations of the ester C=O group involved
in intramolecular hydrogen bond had a frequency of
1640–1645 cm–1, and the band at 1590–1625 cm–1 was
assigned to vibrations of the endocyclic C=C bond. In
the 13C NMR spectra of these compounds, the spiro
carbon atoms gave signals at δC 64.66–64.72 (C8)
56.73–56.74 ppm (C6), and the olefinic carbon nuclei
(=CH) resonated at δC 74.16–74.38 ppm. The upfield
position of the latter signal was also confirmed by the
EXPERIMENTAL
The IR spectra were recorded on a Specord M80
spectrometer from samples dispersed in mineral oil.
The H and 13C NMR spectra were obtained on
1
a Varian Mercury Plus instrument at 300 and 75 MHz,
respectively; the chemical shifts were measured rela-
tive to hexamethyldisiloxane as internal reference (1H)
or solvent signal (13C). The elemental compositions
were determined on a Leco CHNS analyzer. Sorbfil
plates were used for analytical thin-layer chromatog-
raphy (eluent chloroform–acetone, 9:1; spots were
visualized by treatment with a 3% solution of chloranil
in toluene).
1
two-dimensional H–13C NMR spectrum. As in com-
pounds Ia and Ib, the presence of a chiral spiro carbon
atom (C6) in molecules IIa and IIb makes methylene
protons on C7 diastereotopic, and their signals appear
as two doublets with a 2J value of 13.5–14.0 Hz.
General procedure for three-component con-
densation of trimethoxybenzenes with cyclohexane-
carbaldehyde and nitriles. A mixture of 5 mmol of
1,2,3-, 1,2,4-, or 1,3,5-trimethoxybenzene, 5 mmol of
cyclohexanecarbaldehyde, 5 mmol of the correspond-
ing nitrile, and 2 ml of methylene chloride was added
dropwise under stirring to 3 ml of concentrated sulfuric
acid on cooling on a water bath. The mixture was
stirred for 20 min, poured into a mixture of 20 ml of
25% aqueous ammonia, 20 ml of a saturated solution
of ammonium chloride, and 100 g of crushed ice, and
extracted with methylene chloride (2×50 ml). The
extracts were combined, washed with cold water and
a saturated solution of sodium chloride, and dried over
anhydrous MgSO4. The solvent was distilled off, and
the residue was subjected to column chromatography
on silica gel (compounds Ia and IIIa; gradient elution
with hexane–ethyl acetate, 5 to 50 vol % of the latter)
or rerecrystallized from appropriate solvent (Ib, IIa,
IIb, IIIb, IIIc).
We also examined three-component condensation
of 1,2,3- and 1,2,4-trimethoxybenzenes with cyclo-
hexanecarbaldehyde and benzonitrile. For comparison,
analogous condensation was performed with 1,3,5-tri-
methoxybenzene. In all cases, the corresponding
dispiro compounds IIIa–IIIc were smoothly obtained
(Scheme 3). Anisotropic effect of the phenyl group
induces downfield shift of the C6 signal in the 13C
NMR spectra of IIIa and IIIb (δC 75–76 ppm) as
compared to I and II; the second spiro carbon atom
(C8) gives a signal at δC 61–64 ppm.
The described three-component condensation of tri-
methoxybenzenes with cyclohexanecarbaldehyde and
nitriles ensures preparation of dispiro compounds I–III
in satisfactory yields (26–69%). We can conclude that
the use of cyclohexanecarbaldehyde as two-carbon
synthon gives essentially the same results as in the
condensation with isobutyraldehyde.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 3 2009

SPIROCYCLOHEXADIENONES: X.
363
(1H, 5-H), 8.34 br.s (1H, NH). 13C NMR spectrum
(DMSO-d6), δC, ppm: 14.55 (CH2CH3); 23.47, 24.60,
38.18 (CH2); 43.44 (C7); 54.57, 54.86 (OCH3); 56.73
(C6); 57.95 (OCH2); 64.66 (C8); 74.38 (CH=); 101.86
(C2); 115.52 (C5); 148.28 (C4); 163.46 (C1); 169.53
(C15); 174.44 (C=O); 180.95 (C3). Found, %: C 66.25;
H 7.53; N 3.86. C20H27NO5. Calculated, %: C 66.46;
H 7.53; N 3.88.
Methyl [(6RS)-1,2-dimethoxy-3-oxo-14-azadi-
spiro[5.1.5.2]pentadeca-1,4-dien-(15Z)-ylidene]ace-
tate (Ia). Yield 40%, mp 103–104.5°C (from aqueous
ethanol). IR spectrum, ν, cm–1: 3320 (NH), 1746
(C=O), 1660 (C=O, ester), 1602 (C=C). 1H NMR spec-
trum (CDCl3), δ, ppm: 1.28–1.64 m (10H, CH2), 1.92 d
(1H, 7-H, J = 13.5 Hz), 2.26 d (1H, 7-H, J = 13.5 Hz),
3.57 s (3H, OCH3), 3.69 s (3H, OCH3), 3.99 s (3H,
OCH3), 4.2 s (1H, CH=), 6,02 d (1H, 4-H, J =
10.2 Hz), 6.40 d (1H, 5-H, J = 10.2 Hz), 8.24 br.s (1H,
NH). Found, %: C 65.57; H 7.23; N 3.96. C19H25NO5.
Calculated, %: C 65.69; H 7.25; N 4.03.
(6RS)-1,2-Dimethoxy-15-phenyl-14-azadispiro-
[5.1.5.2]pentadeca-1,4,14-trien-3-one (IIIa). Yield
62%, mp 110–111°C (from hexane). IR spectrum, ν,
cm–1: 1652 (C=O); 1636 (C=C); 1616 (C=N); 1594,
1532, 1496 (C=Carom); 1322, 1288, 1204, 1156, 1100,
Ethyl [(6RS)-1,2-dimethoxy-3-oxo-14-azadispiro-
[5.1.5.2]pentadeca-1,4-dien-(15Z)-ylidene]acetate
(Ib). Yield 55%, mp 95–97°C (from EtOH). IR spec-
trum, ν, cm–1: 3320 (NH), 1716 (C=O), 1652 (C=O,
1
1054, 1012, 968, 870, 830. H NMR spectrum
(CDCl3), δ, ppm: 1.33–1.94 m (10H, CH2), 2.13 d
(1H, 7-H, J = 13.5 Hz), 2.30 d (1H, 7-H, J = 13.5 Hz),
3.69 s (3H, OCH3), 3.90 s (3H, OCH3), 6.24 s (1H,
4-H), 6.65 s (1H, 5-H), 7.28 pseudotriplet (2H, 3′-H,
5′-H, J = 7.5 Hz), 7.33 pseudotriplet (1H, 4′-H, J =
7.5 Hz), 7.68 pseudodublet (2H, 2′-H, 6′-H, J =
1
ester), 1600 (C=C). H NMR spectrum (CDCl3), δ,
ppm: 1.18 t (3H, CH2CH3, J = 7.2 Hz), 1.39–1.64 m
(10H, CH2), 1.92 d (1H, 7-H, J = 13.8 Hz), 2.26 d (1H,
7-H, J = 13.8 Hz), 3.69 s (3H, OCH3), 3.99 s (3H,
OCH3), 4.05 m (3H, CH=, OCH2), 6.02 d (1H, 4-H,
J = 9.6 Hz), 6.41 d (1H, 5-H, J = 9.6 Hz), 8.28 br.s
(1H, NH). Found, %: C 66.32; H 7.35; N 3.88.
C20H27NO5. Calculated, %: C 66.46; H 7.53; N 3.88.
13
7.5 Hz). C NMR spectrum (CDCl3), δC, ppm: 23.01,
23.36, 25.32, 38.88, 39.20 (CH2); 46.98 (C7); 60.34,
60.79 (OCH3); 64.27 (C8); 76.01 (C6); 126.71**
(Carom); 127.18** (C4); 128.13**, 130.29** (Carom);
133.64 (C2); 138.05 (Carom); 146.65 (C5); 162.36 (C1);
163.97 (C15); 184.09 (C3). Found, %: C 75.55; H 6.91;
N 3.93. C20H27NO5. Calculated, %: C 75.19; H 7.17;
N 3.99.
Methyl [(6RS)-1,4-dimethoxy-3-oxo-14-azadi-
spiro[5.1.5.2]pentadeca-1,4-dien-(15Z)-ylidene]ace-
tate (IIa). Yield 48%, mp 167.5–168.5°C (from
EtOH). IR spectrum, ν, cm–1: 3330 (NH); 1705 (C=O);
(6RS)-1,4-Dimethoxy-15-phenyl-14-azadispiro-
[5.1.5.2]pentadeca-1,4,14-trien-3-one (IIIb). Yield
69%, mp 176–178°C (from hexane–CH2Cl2). IR spec-
trum, ν, cm–1: 1645 (C=O), 1630 (C=C), 1580 (C=N).
1H NMR spectrum (CDCl3), δ, ppm: 1.40–1.89 m
(10H, CH2), 2.17 d (1H, 7-H, J = 13.5 Hz), 2.36 d (1H,
7-H, J = 13.5 Hz), 3.64 s (6H, OCH3), 5.56 s (1H,
7-H), 5.73 s (1H, 5-H), 7.30 m (3H, Harom), 7.67 d (2H,
Harom, J = 7.8 Hz). 13C NMR spectrum (DMSO-d6), δC,
ppm: 22.90, 23.04, 25.26 (CH2); 49.08 (C7); 55.01,
56.69 (OCH3); 61.28 (C8); 75.36 (C6); 102.27 (C2);
115.53 (C5); 127.10, 128.29, 130.23, 133.51 (Carom);
149.18 (C4); 163.97 (C5); 175.41 (C15); 180.65 (C3).
Found, %: C 75.01; H 7.07; N 3.95. C22H25NO3·
0.5H2O. Calculated, %: C 75.19; H 7.17; N 3.99.
1
1640 (C=O, ester); 1600, 1585 (C=C). H NMR spec-
trum (CDCl3), δ, ppm: 1.46–1.69 m (10H, CH2), 2.02 d
(1H, 7-H, J = 13.5 Hz), 2.36 d (1H, 7-H, J = 13.5 Hz),
3.61 s (3H, OCH3), 3.65 s (3H, OCH3), 3.72 s (3H,
OCH3), 4.21 s (1H, CH=), 5.42 s (1H, 2-H), 5.63 s
(1H, 5-H), 8.34 br.s (1H, NH). 13C NMR spectrum
(DMSO-d6), δC, ppm: 23.50, 24.63, 38.20 (CH2); 43.45
(C7); 49.72, 54.62, 54.89 (OCH3); 56.74 (C6); 64.72
(C8); 74.16 (CH=); 101.92 (C2); 115.53 (C5); 148.35
(C4); 163.56 (C1); 169.86 (C15); 174.46 (C=O); 180.97
(C3). Found, %: C 65.48; H 7.22; N 3.95. C19H25NO5.
Calculated, %: C 65.69; H 7.25; N 4.03.
Ethyl [(6RS)-1,2-dimethoxy-3-oxo-14-azadispiro-
[5.1.5.2]pentadeca-1,4-dien-(15Z)-ylidene]acetate
(IIb). Yield 26%, mp 158–159°C (from EtOH). IR
spectrum, ν, cm–1: 3320 (NH); 1710 (C=O); 1645
(6RS)-1,5-Dimethoxy-15-phenyl-14-azadispiro-
[5.1.5.2]pentadeca-1,4,14-trien-3-one (IIIc). Yield
51%, mp 177–179°C (from hexane–CH2Cl2). IR spec-
trum, ν, cm–1: 1656 (C=O), 1624 (C=C), 1588 (C=N).
1H NMR spectrum (CDCl3), δ, ppm: 1.32–1.86 m
(10H, CH2), 2.22 s (2H, 7-H), 3.63 s (6H, OCH3),
1
(C=O, ester); 1625, 1590 (C=C). H NMR spectrum
(CDCl3), δ, ppm: 1.23 t (3H, CH2CH3, J = 7.2 Hz),
1.45–1.68 m (10H, CH2), 2.00 d (1H, 7-H, J =
14.0 Hz), 2.36 d (1H, 7-H, J = 14.0 Hz), 3.65 s (3H,
OCH3), 3.72 s (3H, OCH3), 4.07 q (2H, OCH2, J =
6.9 Hz), 4.20 s (1H, CH=), 5.42 s (1H, 2-H), 5.63 s
** Alternative assignment is possible.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 45 No. 3 2009

PLEKHANOVA et al.
364
14. Ashimori, A., Bachand, B., Overman, L.E., and
5.55 s (2H, 2-H, 4-H), 7.29 m (3H, Harom), 7.67 d (2H,
Poon, D.J., J. Am. Chem. Soc., 1998, vol. 120, p. 6477.
Harom, J = 8.1 Hz). Found, %: C 75.02; H 6.97; N 3.86.
15. Trzoss, M. and Brimble, M., Synlett, 2003, p. 2042.
C22H25NO3. Calculated, %: C 75.19; H 7.17; N 3.99.
16. Santra, S. and Andreana, P.R., Org. Lett., 2007, vol. 9,
The authors thank scientific worker E.V. Baigache-
va for performing elemental analysis.
p. 5035.
17. Ovens, C., Martin, N.G., and Procter, D.J., Org. Lett.,
2008, vol. 10, p. 1441.
18. Pigge, F.C. and Fang, S., Tetrahedron Lett., 2001,
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