Sodium acetate catalyzed multicomponent cyclization of aromatic aldehydes, acetone and meldrum acid

Article abstract of DOI:10.1002/cjoc.201190020

The sodium acetate catalyzed three-component reaction of aromatic aldehyde, acetone and Meldrum acid or spirolactone at room temperature gave stereospecific 7,11-cis-diaryl-2,4-dioxaspiro[5,5]undecane-1,5,9-triones in a very efficient manner. The sodium a

Full text of DOI:10.1002/cjoc.201190020

FULL PAPER
Sodium Acetate Catalyzed Multicomponent Cyclization of
Aromatic Aldehydes, Acetone and Meldrum Acid
An, Lina(安琳)
Yang, Fengb(杨芬)
Yao, Rongb(姚荣)
Yan, Chaoguo*,b(颜朝国)
a College of Pharmacy, Xuzhou Medical College, Xuzhou, 221004 Jiangsu, China
b College of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
The sodium acetate catalyzed three-component reaction of aromatic aldehyde, acetone and Meldrum acid or spi-
rolactone at room temperature gave stereospecific 7,11-cis-diaryl-2,4-dioxaspiro[5,5]undecane-1,5,9-triones in a
very efficient manner.
Keywords multicomponent reactions, meldrum acid, spiro compounds, stereospecificity, Knoevenagel condensa-
tion
Introduction
ticomponent reaction of aryl aldehydes, malononitrile
and acetone in the presence of a catalytic amount of
sodium acetate, which were stereoselectively
cyclized into cis-4-dicyanomethylene-2,6-diarylcyclo-
hexane-1,1-dicarbonitriles in 30%—60% yields.14 This
report promotes us to develop this methodology to the
condensation reaction of other active methylene com-
pounds such as Meldrum acid and dimedone. When a
mixture of benzaldehyde (3.0 mmol), Meldrum acid (1.5
mmol) and acetone (15 mL) in the presence of anhy-
drous sodium acetate was stirred at room temperature
for about 2 d, the spirocyclic compound 1a was ob-
tained in 59% yield after workup. The reaction condi-
tions were simple and briefly optimized. If the reaction
was conducted in higher temperature (50—60 ℃) the
desired product is difficult to separate due to other by-
products formed. Adding more sodium acetate did not
increase the yield of product because its solubility in
acetone is very low. Under similar reaction conditions
other aromatic aldehydes gave the expected spirocyclic
compounds 1b—1f (Table 1) in 43%—85% yields. It
should be pointed that a similar three-component path-
way using the above mentioned starting materials or
using aldehyde, benzalacetone and Meldrum acid in the
presence of chiral pyrrolidine derivatives as catalyst had
already been described by Ramachary and Barbas,10-12
and such kind of spirocyclic compounds have been pre-
pared by other synthetic methods.16-19 It is interesting to
find that the prepared siprocyclic compounds in this
work were in very pure form because they gave high
quality of analytical data only after crystallization in
acetone. Aromatic aldehydes with p-chloro, p-bromo,
p-methoxyl and p-t-butyl groups showed similar reac-
tivity. When 1,5-dioxaspiro[5,5]undecane-2,4-dione
was used in place of Meldrum acid, the desired dispiro-
Multicomponent reactions (MCRs) with at least
three different substrates reacting in a well-defined
manner to form a single compound have emerged as an
effective tool for atom economic and benign organic
synthesis.1,2 Due to their convergence, productivity, fac-
ile execution and generation of highly diverse products
from easily available starting materials, the design of
multi-component reactions is an important field of re-
search from the point of view of organic synthesis and
combinatorial chemistry.3,4 The domino Knoevenagel
hetero-Diels-Alder reaction represents one of the most
effective methods for the synthesis of heterocyclic
compounds, especially for natural products synthesis.5,6
In recent years, the hetero-Diels-Alder reactions have
been used widely in numerous reactions of prominence
in organic synthesis, because of their economical and
stereo-controlled nature. These reactions allow the for-
mation of two or more rings at once and avoid sequen-
tial chemical transformations.7,8 However, only a few
examples of domino carbon Knoevenagel/Diels-Alder
reaction have been reported and the examples given in
the literature are restricted to using organic amine and
amino acid as organocatalyst for enantioselective syn-
thesis.9-13 In this paper, we wish to report using sodium
acetate as catalyst for the stereospecific preparation of
the spirocyclic compounds via the three component re-
actions of aromatic aldehydes, acetone and Meldrum
acid or 1,5-dioxaspiro[5,5]undecane-2,4-dione.
Results and discussion
Sodium acetate is a mild base catalyst and has been
widely used in many condensation reactions and multi-
component reactions.14,15 Elinson et al. described a mul-
*
E-mail: cgyan@yzu.edu.cn
Received January 21, 2010; revised August 16, 2010; accepted August 24, 2010.
Project supported by the National Natural Science Foundation of China (No. 20972132).
Chin. J. Chem. 2010, 28, 2451— 2454
© 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
2451

An et al.
FULL PAPER
cyclic compounds 1g—1j were obtained in 57%—86%
yields. The formation of the spirocyclic compounds
1a— 1j could be rationalized by domino Knoevenagel
condensation, aldol condensation and Michael addition
reaction.
that is two sets of dd quartets and one triplet for two
bridging CH groups and two CH2 groups.
1
According to the carefully analysis of H NMR data
and comparison with the earlier reported results,9-13 we
could tentatively conclude that the two aryl groups in
spiranes 1a— 1l were in the cis-position, and this so-
dium acetate catalyzed multicomponent reaction is a
diastereospecific catalytic reaction. The X-ray diffrac-
tion determination of single crystals 1b and 1c (Figure 2)
further confirmed this conclusion. It is clearly seen that
the cyclohexanone ring existed in chair conformation
and the two p-chlorophenyl groups existed in cis equa-
torial orientation.
Table 1 Synthesis of 7,11-cis-diaryl-2,4-dioxaspiro[5.5]-un-
decane-1,5,9-triones
Entry Compd.
R
Ar
Yield/%
59
1
2
3
4
5
1a
1b
1c
1d
1e
1f
CH3
CH3
CH3
CH3
CH3
CH3
(CH2)5
(CH2)5
(CH2)5
(CH2)5
C6H5
p-CH3C6H4
p-ClC6H4
66
48
43
50
85
57
58
71
p-BrC6H4
p-CH3OC6H4
p-(CH3)3CC6H4
C6H5
p-CH3C6H4
p-CH3OC6H4
p-(CH3)3CC6H4
6
7
8
9
1g
1h
1i
Figure 2 The molecular structure of compound 1c.
10
1j
86
To explain the mechanism of this one-pot multi-
component reaction, we proposed a plausible reaction
course, which is illustrated in Scheme 1. The first step is
aldol condensation of aromatic aldehyde with acetone to
give arylideneacetone (A) and Knoevenagel condensa-
tion of aromatic aldehyde with Meldrum acid to yield
the arylidenemeldrum acid (B). The second step is
Michael addition of remained methyl group of
arylideneacetone (A) to intermediate (B) to give the
addition intermediate (C). The third step is the in-
tramolecular Michael addition in intermediate (C) to
give the final cyclization product. In this straightforward
mechanism sodium acetate acted as basic catalyst to
The structure of the prepared spirocyclic compounds
1
1a—1j were fully characterized by H, 13C NMR, MS,
IR spectra and confirmed by X-ray diffraction
determination of two single crystals of 1b and 1c. The
1H NMR data clearly indicated all products 1a— 1j are
1
in cis-spirane disastereomer. As for an example, H
NMR spectrum of 1i displays a singlet for two methoxyl
groups at δ 3.76, which clearly show the two p-meth-
oxyphenyl groups and two CH units in same environ-
ment. The two protons at CH units show a dd quartet
peak at δ 3.94 due to the coupling of CH2 groups at 8-
and 10-position. The two CH2 groups at 8- and
10-positions also display two sets of mixed peaks for
protons at axial and equatorial positions. The two axial
protons show one triplet at δ 3.66 with J＝14.4 Hz,
while the two protons at equatorial position display an-
other dd quartet at δ 2.60 (Figure 1). 1H NMR spectra of
other spiranes also show similar kind of peak pattern,
Scheme 1 Formation mechanism of spiro compound 1
Figure 1 The partial 1H NMR spectrum of compound 1i.
2452
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© 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2010, 28, 2451— 2454

Sodium Acetate Catalyzed Multicomponent Cyclization
accomplish the sequential aldol condensation, Knoeve-
nagel condensation and Michael addition reaction.
The reactivity of other active methylene compounds
such as cyclohexane-1,3-dione, dimedone, barbituric
acid and 4-hydroxycoumarin in this reaction were also
tested. It is pity to find that the reaction only stopped at
the stage of Knoevenagel condensation and could went
further to give cyclization products, even using previ-
ously prepared 1,3-dibenzalacetone to react with dime-
done with sodium acetate as catalyst in acetone. After
workup the condensation product of dimedone with two
molar benzaldehyde was separated as main product,
which clearly come from the transformation of ben-
zalidene group from 1,3-dibenzalacetone. This result
demonstrated that this multicomponent reaction is con-
trolled by many complicated factors.
m/z (%): 405.46 ([M－1]＋, 100).
3,3-Dimethyl-7,11-di(p-chlorophenyl)-2,4-dioxa-
spiro[5.5]undecane-1,5,9-trione (1c)
White solid,
1
yield 48%; m.p. 194—196 ℃; H NMR (CDCl3, 600
MHz) δ: 7.33 (d, J＝2.4 Hz, 4H, ArH), 7.17 (d, J＝8.4
2
3
Hz, 4H, ArH), 3.98 (dd, JHH＝14.4 Hz, JHH＝4.2 Hz,
2
2H, 2CH), 3.65 (t, J＝15.0 Hz, 2H), 2.63 (dd, JHH
＝
3
14.4 Hz, JHH＝4.2 Hz, 2H), 0.67 (s, 6H, 2CH3); 13C
NMR (CDCl3, 150 MHz) δ: 206.3, 167.9, 165.0, 135.4,
134.8, 129.3, 129.8, 129.4, 106.5, 60.3, 49.4, 42.7, 28.5;
IR (KBr) ν: 2999 (m), 2924 (w), 1918 (w), 1727 (vs),
1594 (m), 1492 (s), 1417 (m), 1388 (m), 1286 (s), 1019
－1
(m), 984 (m), 839 (s), 680 (w) cm ; MS m/z (%):
445.53 ([M－1]＋, 100), 447.33 ([M＋1]＋, 95).
3,3-Dimethyl-7,11-di(p-bromophenyl)-2,4-dioxa-
spiro[5.5]undecane-1,5,9-trione (1d) White solid,
1
In summary we have developed a three component
reaction involving aromatic aldehydes, acetone with
Meldrum acid or 1,5-dioxaspiro[5,5]undecane-2,4-dione
catalyzed by sodium acetate. This simple and practical
approach can be used to prepare efficiently spiranes and
dispiranes in a diastereospecific fashion.
yield 43%; m.p. 200—202 ℃; H NMR (CDCl3, 600
MHz) δ: 7.48 (d, J＝8.4 Hz, 4H, ArH), 7.11 (d, J＝8.4
2
3
Hz, 4H, ArH), 3.96 (dd, JHH＝14.4 Hz, JHH＝4.2 Hz,
2
2H, 2CH), 3.64 (t, J＝15.0 Hz, 2H), 2.62 (dd, JHH
＝
3
15.2 Hz, JHH＝4.2 Hz, 2H), 0.68 (s, 6H, 2CH3); 13C
NMR (CDCl3, 150 MHz) δ: 206.2, 167.9, 165.0, 135.9,
132.3, 130.1, 122.8, 106.5, 60.1, 49.5, 42.6, 28.5; IR
(KBr) ν: 3034 (w) 2996 (m), 2924 (w), 1726 (vs), 1586
(m), 1489 (s), 1371 (m), 1287－(s), 1070 (m), 984 (m),
Experimental
1
General procedure for the three component reaction
of aldehyde, acetone and Meldrum acid
839 (m), 833 (s), 722 (w) cm ; MS m/z (%): 535.53
([M－1]＋, 100), 537.00 ([M＋1]＋, 65).
A solution of aromatic aldehyde (3.0 mmol), Mel-
drum acid (1.5 mmol) or 1,5-dioxaspiro[5,5]undecane-
2,4-dione (1.5 mmol) and anhydrous sodium acetate
(0.30 g) in 15 mL of acetone was stirred at room tem-
perature for about 48 h. The solvent was evaporated and
the residue was washed with water to give the crude
product, which was then recrystallized from acetone to
yield pure product for analysis.
3,3-Dimethyl-7,11-di(p-methoxyphenyl)-2,4-di-
oxaspiro[5.5]undecane-1,5,9-trione (1e)10 Light yel-
low solid, yield 50%; m.p.173—175 ℃; 1H NMR
(CDCl3, 600 MHz) δ: 7.15 (d, J＝8.4 Hz, 4H, ArH),
6.85 (d, J＝8.4 Hz, 4H, ArH), 3.94 (dd, 2JHH＝14.4 Hz,
3JHH＝3.6 Hz, 2H, 2CH), 3.76 (s, 6H, 2OCH3), 3.65 (t,
2
3
J＝14.4 Hz, 2H), 2.60 (dd, JHH＝14.4 Hz, JHH＝3.6
Hz, 2H), 0.65 (s, 6H, 2CH3); 13C NMR (CDCl3, 150
MHz) δ: 206.2, 166.8, 163.8, 158.9, 127.9, 127.6, 112.8,
104.7, 59.3, 53.7, 47.6, 41.5, 26.9; IR (KBr) ν: 2949 (m),
2840 (w), 1725 (vs), 1610 (m), 1513 (s), 1456 (m), 1379
3,3-Dimethyl-7,11-diphenyl-2,4-dioxaspiro[5.5]-
undecane-1,5,9-trione (1a)10
Light yellow solid,
1
yield 59%; m.p. 203—206 ℃; H NMR (CDCl3, 600
－1
MHz) δ: 7.35—7.28 (m, 6H, ArH), 7.24 (d, J＝7.2 Hz,
(m), 1285 (s), 1029 (m), 838 (m) cm ; MS m/z (%):
4H, ArH), 4.03 (dd, JHH＝15.0 Hz, JHH＝4.2 Hz, 2H,
437.27 ([M－1]＋, 100).
2
3
2
2CH), 3.73 (t, J＝15.0 Hz, 2H, CH), 2.66 (dd, JHH
＝
3,3-Dimethyl-7,11-di(p-tert-butylphenyl)-2,4-di-
oxaspiro[5.5]undecane-1,5,9-trione (1f) White solid,
3
15.0 Hz, JHH＝4.2 Hz, 2H), 0.55 (s, 6H, 2CH3); 13C
NMR (CDCl3, 150 MHz) δ: 207.5, 168.1, 165.2, 137.1,
129.1, 128.6, 128.4, 106.3, 60.5, 50.1, 42.8, 28.3; IR
(KBr) ν: 3031 (w), 2926 (m), 1726 (vs), 1588 (w), 1491
(m), 1452 (m), 1369 (vs), 1118 (m), 853 (m), 703 (s)
1
yield 85%; m.p. 218—221 ℃; H NMR (CDCl3, 600
MHz) δ: 7.35 (d, J＝8.4 Hz, 4H, ArH), 7.16 (d, J＝8.4
2
3
Hz, 4H, ArH), 4.00 (dd, JHH＝14.4 Hz, JHH＝4.2 Hz,
2
2H, 2CH), 3.72 (t, J＝15.0 Hz, 2H), 2.64 (dd, JHH
＝
－1
3
＋
cm ; MS m/z (%): 377.30 ([M－1] , 100).
15.0 Hz, JHH＝4.2 Hz, 2H), 1.25 (s, 18H, 6CH3), 0.49
(s, 6H, 2CH3); 13C NMR (CDCl3, 150 MHz) δ: 208.1,
168.3, 165.2, 134.0, 128.0, 126.0, 106.2, 60.9, 49.5,
42.7, 34.4, 31.1, 28.0; IR (KBr) ν: 2961 (s), 2871 (w),
1730 (vs), 1572 (w), 1467 (m), 1287 (s), 1180 (w), 838
3,3-Dimethyl-7,11-di(p-methylphenyl)-2,4-dioxa-
spiro[5.5]undecane-1,5,9-trione (1b) White solid,
1
yield 66%; m.p. 208—210 ℃; H NMR (CDCl3, 600
MHz) δ: 7.14—7.10 (m, 8H, ArH), 3.96 (dd, 2JHH＝14.4
＋
3
－1
Hz, JHH＝4.2 Hz, 2H, 2CH), 3.68 (t, J＝14.4 Hz, 2H),
(m), 572 (m) cm ; MS m/z (%): 488.86 ([M－1] ,
2.60 (dd, 2JHH＝15.0 Hz, 3JHH＝4.8 Hz, 2H), 2.28 (s, 6H,
2CH3), 0.59 (s, 6H, 2CH3); 13C NMR (CDCl3, 150 MHz)
δ: 207.9, 168.3, 165.4, 138.4, 134.1, 130.1, 129.7, 128.3,
106.2, 60.6, 49.7, 43.0, 28.2, 21.0; IR (KBr) ν: 3003 (w)
2920 (m), 1753 (m), 1723 (vs), 1576 (s), 1512 (s－), 1416
100).
11,5-Bis-phenyl-8,15-dioxadispiro[5.2.5.2]hexade-
cane-3,7,16-trione (1g)10 White solid, yield 57%; m.p.
1
210—212 ℃; H NMR (CDCl3, 600 MHz) δ: 7.35—
7.28 (m, 6H, ArH), 7.24 (d, J＝7.2 Hz, 4H, ArH), 4.00
1
2
3
(w), 1289 (m), 1107 (w), 892 (w), 722 (m) cm ; MS
(dd, JHH＝14.4 Hz, JHH＝4.2 Hz, 2H, 2CH), 3.73 (t,
Chin. J. Chem. 2010, 28, 2451— 2454
© 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
2453

An et al.
FULL PAPER
＋
－1
J＝14.4 Hz, 2H), 2.65 (d, 2JHH＝14.4 Hz, 3JHH＝4.2 Hz,
(m), 712 (w) cm ; MS m/z (%): 529.38 ([M－1] ,
2H), 1.13—1.23 (m, 6H, 3CH2), 0.48 (s, 4H, 2CH2); 13
C
100).
NMR (CDCl3, 150 MHz) δ: 207.5, 168.4, 165.4, 137.2,
129.0, 128.5, 126.4, 106.7, 61.1, 50.1, 42.9, 37.2, 23.6,
21.6; IR (KBr) ν: 2945 (m), 1758 (vs), 1578 (m), 1513
(m), 1420 (m), 1368 (m), 1259 (vs), 1183 (m), 1034 (m),
Supplement data
The single crystal data of compounds 1b and 1c have
been deposited at the Cambridge Crystallographic Da-
tabase Centre with CCDC 755442 (1b) and 755443
(1c).
＋
－1
831 (m), 530 (m) cm ; MS m/z (%): 417.40 ([M－1] ,
100).
1,5-Bis-p-methylphenyl-8,15-dioxadispiro[5.2.5.2]-
hexadecane-3,7,16-trione (1h) White solid, yield
58%; m.p. 178—180 ℃; 1H NMR (CDCl3, 600 MHz) δ:
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7.12—7.09 (m, 8H, ArH), 3.96 (dd, JHH＝15.0 Hz,
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3JHH＝4.2 Hz, 2H, 2CH), 3.69 (t, J＝14.4 Hz, 2H), 2.61
2
3
(dd, JHH＝14.4 Hz, JHH＝4.2 Hz, 2H), 2.28 (s, 6H,
2CH3), 1.24—1.14 (m, 6H, 3CH2), 0.52 (s, 4H, 2CH2);
13C NMR (CDCl3, 150 MHz) δ: 208.1, 168.6, 165.6,
138.4, 134.2, 129.6, 128.2, 106.7, 61.2, 49.7, 43.0, 37.2,
23.6, 21.7, 20.9; IR (KBr) ν: 2930 (s), 2862 (w), 1726
(vs), 1576 (m), 1513 (w), 1411 (w), 1268 (m), 1074 (m),
3
4
5
6
7
－1
825 (m), 722 (w), 523 (m) cm ; MS m/z (%): 445.29
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[5.2.5.2]hexadecane-3,7,16-trione (1i)10 White solid,
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1
yield 71%; m.p. 183—186 ℃; H NMR (CDCl3, 600
MHz) δ: 7.14 (d, J＝4.8 Hz, 4H, ArH), 6.84 (d, J＝8.4
2
3
Hz, 4H, ArH), 3.94 (dd, JHH＝14.4 Hz, JHH＝4.2 Hz,
2H, 2CH), 3.76 (s, 6H, 2OCH3), 3.66 (t, J＝14.4 Hz,
2
3
2H), 2.60 (dd, JHH ＝15.0 Hz, JHH ＝4.2 Hz, 2H)
1.28—1.16 (m, 6H, 3CH2), 0.59 (s, 4H, 2CH2); 13C
NMR (CDCl3, 150 MHz) δ: 207.9, 168.7, 165.7, 159.6,
129.5, 129.3, 114.36, 106.8, 61.6, 55.4, 49.3, 43.2, 37.4,
23.7, 21.8; IR (KBr) ν: 2940 (m), 1726 (vs), 1436 (m),
－1
1301 (s), 1206 (s), 920 (m), 767 (w), 558 (m) cm ; MS
m/z (%): 477.53 ([M－1]＋, 100).
1,5-Bis-p-tert-butylphenyl-8,15-dioxadispiro-
[5.2.5.2]hexadecane-3,7,16-trione (1j) White solid,
1
yield 86%; m.p. 254—256 ℃; H NMR (CDCl3, 600
MHz) δ: 7.33 (d, J＝8.4 Hz, 4H, ArH), 7.15 (d, J＝8.4
2
3
Hz, 4H, ArH), 3.99 (dd, JHH＝14.4 Hz, JHH＝4.2 Hz,
2H, 2CH), 3.72 (t, J＝14.4 Hz, 2H), 2.64 (dd, 2JHH
＝
3
14.4 Hz, JHH＝4.8 Hz, 2H), 1.24 (s, 18H, 6CH3), 1.27
—1.11 (m, 6H, 3CH2), 0.43—0.41 (m, 4H, 2CH2); 13C
NMR (CDCl3, 150 MHz) δ: 208.2, 168.4, 165.3, 151.8,
134.1, 128.0, 125.9, 106.6, 61.4, 49.4, 37.1, 34.5, 31.2,
23.6, 21.6; IR (KBr) ν: 2959 (s) 2866 (w), 1762 (w),
1726 (vs), 1580 (m), 1512 (w), 1416 (w), 1280 (m), 836
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Chin. J. Chem. 2010, 28, 2451— 2454