One-pot multicomponent condensation reaction of aldehydes with cyclic ketones

Article abstract of DOI:10.1080/00397911003706990

Under microwave irradiation, the one-pot multicomponent condensation reaction of three molar aromatic aldehydes with two molar cyclic ketones having free,'-methylene positions such as cyclopentanone or cyclohexanone in the presence of ammonium acetate and

Full text of DOI:10.1080/00397911003706990

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One-Pot Multicomponent Condensation
Reaction of Aldehydes with Cyclic
Ketones
Ping Wu a , Xi-Mei Cai b , Qi-Fang Wang b & Chao-Guo Yan b
a Yangzhou Polytechnic University, Yangzhou, China
b College of Chemistry and Chemical Engineering, Yangzhou
University, Yangzhou, China
Version of record first published: 25 Feb 2011
To cite this article: Ping Wu, Xi-Mei Cai, Qi-Fang Wang & Chao-Guo Yan (2011): One-Pot
Multicomponent Condensation Reaction of Aldehydes with Cyclic Ketones, Synthetic Communications:
An International Journal for Rapid Communication of Synthetic Organic Chemistry, 41:6, 841-850
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Synthetic Communications1, 41: 841–850, 2011
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397911003706990
ONE-POT MULTICOMPONENT CONDENSATION
REACTION OF ALDEHYDES WITH CYCLIC KETONES
Ping Wu,1 Xi-Mei Cai,2 Qi-Fang Wang,2 and Chao-Guo Yan2
1Yangzhou Polytechnic University, Yangzhou, China
2College of Chemistry and Chemical Engineering, Yangzhou University,
Yangzhou, China
GRAPHICAL ABSTRACT
Abstract Under microwave irradiation, the one-pot multicomponent condensation reaction
of three molar aromatic aldehydes with two molar cyclic ketones having free a,a0-methylene
ethylene positions such as cyclopentanone or cyclohexanone in the presence of ammonium
acetate and acetic acid afforded dicyclocalkenopyridines with two a-arylidene groups in
good yields. In similar reaction conditions, 1-tetralone, which has only one a-methylene
position, results in 10-aryl-2,3:5,6-dibenzoacridines.
Keywords Acridine; aldol condensation; aromatic aldehyde; cyclic ketone; microwave
irradiation; pyridine
INTRODUCTION
The pyridyl heterocyclic core is a widespread subunit in numerous natural
products and pharmaceuticals. These facts consequently generate interest in develop-
ing a new efficient synthetic procedure of pyridines.[1–4] Polysubstituted pyridines
have been synthesized using various methods and procedures, and two methods have
distinct advantages over other procedures. One is the two-step Kro¨hnke synthesis[5–9]
via condensation of pyridinium salts with a,b-unsaturated ketones in the presence of
a mixture of ammonium acetate and acetic acid. The second method is Hantzsch-
type synthesis via cyclocondensation of aromatic aldehyde, acetophenone, and a
Received March 19, 2008.
Address correspondence to Chao-Guo Yan, College of Chemistry and Chemical Engineering,
Yangzhou University, Yangzhou, China. E-mail: cgyan@yzu.edu.cn
841

842
P. WU ET AL.
nitrogen derivative such as ammonium acetate or urea.[10] The key step of this
reaction is Michael addition of the second molecule of acetophenone to a,b-unsatu-
rated ketones formed in situ from the aldol condensation of aromatic aldehyde with
acetophenone to form 1,5-diketone. Recently, several improved procedures have
been developed for this method, including solvent-free reaction conditions,[11,12]
reaction in aqueous media,[13]
a
one-pot procedure under microwave
irradiation,[14,15] and direct heating of a,b-unsaturated ketones and ammonium acet-
ate in the presence of a catalytic amount of acetic acid.[16] In continuation of our
efforts to develop new, facile, and efficient synthetic methods for polysubstituted
pyridines, herein we report the interesting results of microwave-assisted one-pot
reactions of aromatic aldehydes with cyclic ketones.
RESULTS AND DISCUSSION
When a mixture of cyclopentanone 1a, aromatic aldehydes 2a–f, ammonium
acetate, and acetic acid was heated under microwave irradiation, Hantzsch-type syn-
thesis of pyridine occurred with the formation of dicyclopenta[b,e]pyridines. After
workup, in our experiments the main products were dicyclopenta[b,e]pyridines with
two additional a-arylidene groups. Then an optimized molar ratio of aromatic alde-
hydes (3 mol) and cyclopenanone (2 mol) was used in the same reactions. Com-
pounds 3a–e were prepared in 65–78% yields. Cyclohexanone 1b reacted similarly
to give dicyclohexa[b,e]pyridine (sym-ocathydroacridine) with two additional benzy-
lidene groups 3f–j (Scheme 1).
The dibenzylidene derivatives of dicyclocalkenopyridines have been prepared
by several methods in the literature. One is conventionally heating the mixture of
aldehyde, cyclic ketone, and ammonium acetate.[17] The second is heating dicy-
cloalkenopyridines with aromatic aldehyde in acetic anydride.[18] The third is letting
cyclic ketone react with formaldedyde to form bis (2-oxocycloalkyl)methane, which
in turn is heated with ammonium acetate.[19] The structures of the dicycloalkeno-
1
pyridine derivatives 3a–j were characterized by infrared (IR), H NMR, and 13C
NMR, as well as mass spectroscopy. It should be mentioned that the reaction under
microwave irradiation is very clean, and very few by-products have been detected.
Scheme 1. One-pot synthesis of dicycloalkenopyridines 3a–j.

ONE-POT MULTICOMPONENT CONDENSATION
843
Figure 1. Molecular structure of 3g. Hydrogen atoms are omitted for clarity.
Therefore, the workup procedure involves only a simple filtration of the precipitate
followed by crystallization with alcohol. In all instances, the products can be
1
obtained in a high purity, with very good H and 13C NMR results. Their struc-
tures were further confirmed by x-ray crystal analysis of the representative com-
pound 3g (Fig. 1). In the molecule of 3g, the p-chlorophenyl group in the
4-position of the pyridine ring is torsioned from the plane of the pyridine ring.
Each fused cyclohexene ring is in screw-boat conformation attached to a p-chlorol-
benzylidene group.
The formation of 3a–j is very interesting and involves three molecules of aro-
matic aldehydes and two molecules of ketones as well as one molecule of ammonia.
The reaction mechanism of Hantzsch-type synthesis of pyridine via cyclocondensa-
tion of aromatic aldehyde with acetophenone and a nitrogen source has long been
established,[20–23] which includes several steps: aldol condensation of aromatic alde-
hyde with acetophenone to give a,b-unsaturated ketones, Michael addition of the
second molecule of acetophenone to a,b-unsaturated ketones to form 1,5-diketone,
which in turn cyclizes with a nitrogen source to form a hydropyridine ring. This
kind of mechanism also should apply to the formation of dicycloalkenopyridines.
Scheme 2. One-pot synthesis of dicycloalkenopyridines 4a–e.

844
P. WU ET AL.
Figure 2. Molecular structure of the compound 4c. Hydrogen atoms are omitted for clarity.
According to this mechanism, the 2-substituted cyclic ketone, which has one
methylene group, would produce the normal bicyclic fused pyridines in the reactions.
In fact, when 1-tetralone 1c is heated with aromatic aldehydes in the presence
of NH4OAc=HOAc under microwave irradiation, the normal 10-aryl-2,3–5,6-
dibenzotetrahydroacridines 4a–e are formed in excellent yields (Scheme 2), which
has been reported recently.[14] X-ray crystal structure of 4c (Fig. 2) further confirms
the proposed structures.
EXPERIMENTAL
Material and Apparatus
Melting points were taken on a hot-plate microscope apparatus. IR spectra
1
were obtained on a Bruker Tensor 27 spectrometer (KBr disc). H NMR spectra
were recorded with a Bruker AV-600 spectrometer with CDCl3 as solvent and tetra-
methylsilane (TMS) as internal standard. High-performance liquid chromatography=
mass spectra (HPLC=MS) were measured on a Fennigan LCQ Deca XP MAX
instrument. Microwave heating was conducted with a Lingjiang LMMC-201 micro-
wave reactor (Nanjing, Chnia). Aromatic aldehydes, cyclic ketones, and other
reagents are commercial reagents and were used as received. Solvents were purified
by standard techniques. The reaction process was monitored by thin-layer
chromatography (TLC).

ONE-POT MULTICOMPONENT CONDENSATION
845
Table 1. Crystal data of the compounds 3g and 4c
Parameter
3g
4c
Empirical formula
Formula weight
Temperature (K)
C
34H27Cl6N
662.27
273 (2)
C27H20ClN
393.89
273 (2)
Wavelength (A)
Crystal system, space group
Unit cell dimensions
0.71073
Monoclinic, P2 (1)=n
0.71073
Triclinic, P-1
˚
a (A)
11.8330 (14)
11.2754 (14)
23.607 (3)
8.8056 (13)
10.4493 (15)
11.9107 (17)
79.633 (2)
76.310 (2)
69.007 (2)
988.6 (2)
˚
b (A)
˚
c (A)
a (ꢀ)
b (ꢀ)
c (ꢀ)
90
91.556 (2)
90
3
˚
Volume (A )
Z, calculated density (g cmꢁ3
3148.5 (7)
4, 1.397
)
2, 1.323
0.206
Absorption coefficient (mmꢁ1
F (0 0 0)
Crystal size (mm)
)
0.571
1360
412
0.40 ꢂ 0.30 ꢂ 0.30
2.10 to 25.00
0.30 ꢂ 0.30 ꢂ 0.20
2.50–25.00
h range for data collection (ꢀ)
Limiting indices
ꢁ14 ꢃ h ꢃ 12,ꢁ12 ꢃ k ꢃ 13,
ꢁ28 ꢃ l ꢃ 28
ꢁ10 ꢃ h ꢃ 8, ꢁ12 ꢃ k ꢃ 12,
ꢁ14 ꢃ l ꢃ 13
Reflections collected=unique
Completeness (%)
15923=5539 [R (int) ¼ 0.0374]
99.9
non
5159=3426 [R (int) ¼ 0.0173]
98.4
Absorption correction
Max. and min. transmission
Refinement method
Semi-empirical from equivalents
0.9407 and 0.9220
Full-matrix least-squares on F2
3426=0=262
1.079
0.8943 and 0.8473
Full-matrix least-squares on F2
5539=0=370
Data=restraints=parameters
Goodness of fit on F2
Final R indices [I > 2rI]
R indices (all data)
1.060
R1 ¼ 0.0911, wR2 ¼ 0.2588
R1 ¼ 0.1339, wR2 ¼ 0.1339
1.266 and ꢁ1.103
R1 ¼ 0.0442, wR2 ¼ 0.1075
R1 ¼ 0.0637, wR2 ¼ 0.1188
0.151 and ꢁ0.236
Largest difference peak
ꢁ3
˚
and hole (e A
)
General Procedure for the Preparation of 3a–j
To a 50-mL flask, Aromatic aldehyde (3.0 mmol), cyclic ketone (2.0 mmol),
ammonium acetate (3.0 g), and acetic aid (2.0 mL) were added. The mixture was
put in the microwave and heated for about 2–4 min (520 W). After cooling, the reac-
tion mixture was diluted with 50 mL of water, and the resulting precipitate was col-
lected with filtration. The crude product was recrystallizated with ethanol to give
1
the pure solid sample for analysis with IR, HPLC=MS, and H NMR and 13C
NMR specotroscopy.
Selected Data for 3a–j
Compound 3a. Yield 65%, mp 230.6 ꢀC. 1H NMR (600 MHz, CDCl3) d 7.33
(s, 2H, PhH), 7.62 (d, 4H, J ¼ 7.8 Hz, PhH), 7.50 (t, 2H, J ¼ 7.8 Hz, PhH), 7.44–7.39
(m, 2H, PhH), 7.29–7.27 (m, 3H, PhH, CH ¼), 3.20 (s, 4H, 2CH2), 3.00 (s, 4H,
2CH2). 13C NMR (600 MHz, CDCl3) d 160.9, 143.7, 141.6, 138.0, 138.0, 136.8,

846
P. WU ET AL.
136.8, 129.1, 128.6, 128.4, 128.1, 128.0, 126.7, 122.0, 29.4, 27.7. IR (KBr) t 2913 (w),
2375 (w), 1632 (m), 1493 (m), 1444 (m), 1377 (vs), 1239 (m), 1193 (m), 1077 (w), 816
(w), 761 (m) cmꢁ1. MS (m=z): 411.80.
Compound 3b. Yield 74%, mp 235.6–236.6 ꢀC. 1H NMR (600 MHz, CDCl3) d
7.67 (s, 2H, ArH), 7.43 (d, 4H, J ¼ 7.8 Hz, ArH), 7.27–7.24 (m, 4H, ArH, CH ¼),
7.20–7.19 (d, 4H, ArH, CH ¼), 3.12 (s, 4H, 2CH2), 2.95–2.93 (m, 4H, 2CH2), 2.41 (s,
3H, CH3), 2.37 (s, 6H, CH3). 13C NMR (600MHz, CDCl3) d 135.3, 131.5, 130.7,
129.3, 129.2, 128.6, 128.5, 128.1, 128.0, 127.8, 127.7, 126.5, 120.0, 28.4, 26.7. IR (KBr)
t 3012 (w), 2915 (m), 1632 (m), 1571 (w), 1509 (s), 1453 (w), 1382 (vs), 1294 (w), 1238
(m), 1179 (w), 1123 (w), 1029 (w), 896 (w), 808 (m), 720 (w) cmꢁ1. MS (m=z): 553.67.
1
Compound 3c. Yield 78%, mp >250 ꢀC. H NMR (600 MHz, CDCl3) d7.56
(s, 1H, ArH), 7.43 (d, 3H, J ¼ 8.4 Hz, ArH), 7.39 (d, 2H, J ¼ 7.8 Hz, ArH), 7.29 (d,
4H, J ¼ 7.2 Hz, ArH), 7.23 (d, 2H, J ¼ 7.2 Hz, CH ¼), 7.19 (s, 2H, ArH), 3.06 (d,
J ¼ 7.2 Hz, 4H, 2CH2), 2.89 (d, J ¼ 7.2 Hz, 4H, 2CH2); 13C NMR (600 MHz, CDCl3)
d 136.1, 135.6, 134.7, 133.5, 131.8, 130.9, 129.5, 129.3, 128.7, 128.7, 128.3, 128.2,
128.1, 128.0, 127.9, 126.7, 123.9, 120.4, 120.3, 28.5, 26.9. IR (KBr) t 2912 (w),
2841 (w), 1631 (w), 1537 (w), 1491 (s), 1457 (w), 1357 (m), 1265 (w), 1239 (m),
1130 (w), 1090 (s), 1011 (w), 825 (w), 797 (m), 703 (w) cmꢁ1. MS (m=z): 513.60.
Compound 3d. Yield 70%, mp 186.8 ꢀC. 1H NMR (600 MHz, CDCl3) d 7.65
(s, 2H, ArH), 7.55 (d, 3H, J ¼ 8.4 Hz, ArH), 7.33 (d, 2H, J ¼ 8.4 Hz, CH ¼), 7.28 (s,
1H, ArH), 7.01 (d, 3H, J ¼ 8.4 Hz, ArH), 6.96 (d, 3H, J ¼ 8.4 Hz, ArH), 3.88, 3.86 (s,
s, 9H, 3OCH3), 3.14 (s, 4H, 2CH2), 2.99–2.97 (t, J ¼ 7.2 Hz, 4H, 2CH2); 13C NMR
(600 MHz, CDCl3) d139.4, 131.2, 131.0, 130.4, 130.3, 130.0, 129.4, 127.4, 114.3,
114.09, 114.0, 113.9, 55.3, 29.3, 27.8; IR (KBr) t 2923 (w), 2836 (w), 1605 (m),
1511 (s), 1453 (w), 1383 (w), 1293 (w), 1248 (vs), 1176 (m), 1125 (m), 1031 (w),
814 (w) cmꢁ1. MS (m=z): 501.80.
Compound 3e. Yield 69%, mp >250 ꢀC. 1H NMR (600 MHz, CDCl3) d 9.28
(s, 1H, OH), 9.21 (s, 2H, OH), 7.45 (s, 2H, ArH), 7.15 (s, 2H, ArH), 7.05–7.04 (m,
3H, ArH), 6.90 (s, 2H, ArH), 6.84 (d, 2H, J ¼ 8.4 Hz, CH ¼), 3.84–3.81 (m, 9H,
3OCH3), 3.08 (s, 4H, 2CH2), 2.99 (s, 4H, 2CH2). 13C NMR (600 MHz, CDCl3) d
161.2, 148.5, 148.4, 147.3, 146.8, 144.1, 139.6, 136.7, 130.1, 128.6, 122.8, 122.0,
121.9, 116.6, 116.5, 113.9, 113.4, 57.0, 56.8, 56.5, 40.5, 40.4, 40.21, 40.1, 39.9, 29.7,
28.3, 19.3. IR (KBr) t 2932 (w), 1598 (w), 1513 (vs), 1457 (w), 1382 (m), 1271 (s),
1208 (m), 1123 (m), 1030 (w), 810 (w) cmꢁ1. MS (m=z): 549.67.
Compound 3f. Yield 71%, mp 158.9–159.6 ꢀC. 1H NMR (600 MHz, CDCl3) d
8.36 (s, 2H, PhH), 7.62 (d, 6H, J ¼ 6.6 Hz, PhH), 7.54–7.52 (m, 5H, PhH), 7.41 (d,
2H, J ¼ 7.2 Hz, PhH), 7.29 (d, 2H, J ¼ 7.2 Hz, CH ¼), 3.03 (s, 4H, CH2), 2.60 (s,
4H, CH2), 1.89 (s, 4H, CH2). IR (KBr) t 3052 (w), 3020 (w), 2935 (m), 2858 (w),
1596 (w), 1544 (m), 1492 (m), 1442 (m), 1384 (vs), 1265 (w), 1183 (w), 1032 (w),
918 (w), 967 (w), 867 (w),753 (m), 694 (s), 616 (w). 13C NMR (600 MHz, CDCl3)
d 149.9, 149.5, 138.5, 138.4, 136.4, 129.7, 129.4, 128.7, 128.3, 128.1, 127.4, 126.6,
126.5, 28.2, 27.9, 23.1. MS (m=z): 440.27.
1
Compound 3g. Yield 70%, mp 195.6–196.8 ꢀC. H NMR (600 MHz, CDCl3)
d 8.02 (s, 2H, ArH), 7.38 (d, 2H, J ¼ 7.8 Hz, ArH), 7.30–7.28 (m, 8H, ArH, ¼CH),

ONE-POT MULTICOMPONENT CONDENSATION
847
6.99 (d, 2H, J ¼ 7.8 Hz, ArH), 2.74 (s, 4H, CH2), 2.35 (s, 4H, CH2), 1.67 (s, 4H,
CH2). 13C NMR (600 MHz, CDCl3) d 149.7, 148.5, 136.7, 136.6, 133.6, 132.4,
130.9, 129.7, 129.6, 129.2, 129.1, 128.3, 128.1, 125.7, 125.6, 28.1, 27.8, 22.9. IR
(KBr) t 2932 (w), 1630 (m), 1489 (w), 1385 (s), 1091 (w), 1019 (w), 834 (w), 582
(w) cmꢁ1. MS (m=z): 541.73.
1
Compound 3h. Yield 67%, mp 226.5–228.5 ꢀC. H NMR (600 MHz, CDCl3)
d 7.94 (s, 2H, ArH), 7.24 (d, 4H, J ¼ 8.4 Hz, ArH, CH ¼), 6.88 (d, 2H, J ¼ 8.4 Hz,
ArH), 6.82 (d, 2H, J ¼ 9.0 Hz, ArH), 6.75 (d, 4H, J ¼ 9.0 Hz, ArH), 3.69–3.66 (d,
9H, 3OCH3), 2.68 (t, 4H, J ¼ 6.6 Hz, 2CH2), 2.27 (t, 4H, J ¼ 6.0 Hz, 2CH2), 1.55
(t, 4H, J ¼ 6.0 Hz, 2CH2). 13C NMR (600 MHz, CDCl3) d 158.8, 158.3, 150.0,
135.0, 131.0, 129.5, 129.4, 126.0, 114.1, 113.5, 55.3, 28.2, 28.0, 23.1. IR (KBr) t
2932 (w), 1605 (m), 1507 (s), 1458 (w), 1385 (m), 1248 (vs), 1174 (m), 1029 (m),
839 (m) cmꢁ1. MS (m=z): 529.73.
Compound 3i. Yield 75%, mp 226.4–228.0 ꢀC. 1H NMR (600 MHz, CDCl3) d
7.95 (s, 2H, ArH), 7.05 (d, 2H, J ¼ 9.0 Hz, CH ¼), 6.68 (d, 1H, J ¼ 7.8 Hz, ArH), 6.37
(s, 2H, ArH), 6.30 (s, 4H, ArH), 3.67–3.64 (m, 15H, OCH3), 3.50 (s, 3H, OCH3),
2.61–2.50 (m, 4H, CH2), 2.27–2.14 (m, 4H, CH2), 1.52 (s, 4H, CH2). IR (KBr) t
2935 (w), 2835 (w), 1608 (s), 1502 (m), 1459 (m), 1385 (w), 1293 (m), 1259 (m),
1209 (s), 1159 (s), 1038 (m), 925 (w), 836 (w), 582 (w). 13C NMR (600 MHz, CDCl3)
d 160.5, 159.8, 159.0, 157.2, 149.9, 145.9, 135.6, 131.0, 130.1, 129.9, 121.5, 120.7,
120.0, 104.6, 103.7, 98.8, 98.3, 55.5, 55.4, 28.1, 27.7, 23.0. MS (m=z): 619.53.
1
Compound 3j. Yield 72%, mp > 250 ꢀC. H NMR (600 MHz, CDCl3) d 8.00
(s, 2H, ArH), 7.62 (d, 4H, J ¼ 8.4 Hz, ArH), 6.90–6.89 (m, 2H, CH ¼), 6.70 (d, 2H,
J ¼ 9.0 Hz, ArH), 6.65 (d, 4H, J ¼ 8.4 Hz, ArH), 2.91 (s, 7H, CH3), 2.88–2.83 (m,
11H, CH3), 2.80–2.78 (m, 4H, CH2), 2.37 (t, 4H, J ¼ 6.0 Hz, CH2), 1.61 (t, 4H,
J ¼ 6.0 Hz, CH2). IR (KBr) t 2927 (w), 1608 (s), 1519 (vs), 1478 (w), 1443 (w),
1384 (m), 1353 (m), 1223 (w), 1188 (w), 1160 (w), 946 (w), 823 (m), 763 (w), 553
(w). 13C NMR (600 MHz, CDCl3) d 149.6, 148.8, 148.6, 148.4, 132.9, 130.2,
128.6, 128.5, 126.3, 125.8, 125.7, 111.6, 111.5, 111.4, 40.0, 39.8, 27.6, 22.6. MS
(m=z): 568.93.
General Procedure for the Preparation of 4a–e
Aromatic aldehyde (1.0 mmol), 1-tetralone (2.0 mmol), ammonium acetate
(3.0 g), and acetic acid (2.0 mL) was added to a 50-mL flask. The mixture was put
into a microwave and heated for about 2–4 min (520 W). After cooling, the reaction
mixture was diluted with 50 mL of water, and the resulting precipitate was collected
by filtration. The crude product was recrystallized with ethanol to give the pure solid
sample.
Selected Data for 4a–e
1
Compound 4a. Yield 68%, mp 164–165 ꢀC. H NMR (600 MHz, CDCl3) d
8.45 (d, 2H, J ¼ 7.8 Hz, ArH), 7.36 (t, 2H, J ¼ 7.2 Hz, ArH), 7.31–7.26 (m, 3H,
ArH), 7.21–7.18 (m, 3H, ArH), 7.08–7.07 (m, 3H, ArH), 2.75–2.68 (m, 4H,

848
P. WU ET AL.
2CH2), 2.53–2.50 (m, 4H, 2CH2). 13C NMR (600 MHz, CDCl3) d 147.8, 145.1, 139.7,
138.3, 135.7, 135.5, 135.4, 133.0, 127.9, 127.3, 126.4, 126.3, 126.3, 126.3, 126.2, 126.0,
125.7, 125.5, 125.3, 125.1, 124.7, 124.6, 124.1, 123.6, 123.4, 123.0, 25.8, 25.2, 23.5. IR
(KBr) t 3029 (w), 2943 (w), 2835 (w), 1631 (w), 1547 (m), 1489 (w), 1434 (w), 1387
(s), 1225 (m), 1167 (w), 1031 (w), 945 (w), 807 (w), 762 (s) cmꢁ1. MS (m=z): 359.60.
1
Compound 4b. Yield 79%, mp 165.2–166.7 ꢀC. H NMR (600 MHz, CDCl3)
d 8.42 (d, 1H, J ¼ 7.2 Hz, ArH), 7.97 (d, 1H, J ¼ 8.4 Hz, ArH), 7.70 (s, 1H, ArH),
7.31 (t, 1H, J ¼ 7.2 Hz, ArH), 7.24 (t, 1H, J ¼ 7.2 Hz, ArH), 7.14 (d, 2H, J ¼ 7.2 Hz,
Hz, ArH), 7.06 (d, 3H, J ¼ 7.2 Hz, ArH), 6.92 (d, 1H, J ¼ 7.8 Hz, ArH), 2.96 (t, 2H,
J ¼ 6.0 Hz, CH2), 2.76 (t, 2H, J ¼ 6.6 Hz, CH2), 2.65 (t, 2H, J ¼ 7.2 Hz, CH2), 2.56 (t,
2H, J ¼ 7.8 Hz, CH2), 2.49 (t, 2H, J ¼ 7.8 Hz, CH2), 2.24 (s, 3H, CH3). 13C NMR
(600 MHz, CDCl3) d 187.9, 150.0, 143.2, 138.8, 137.8, 137.3, 136.8, 135.5, 134.9,
134.8, 133.6, 133.2, 133.1, 130.0, 129.3, 129.2, 128.9, 128.7, 128.6, 128.2, 128.1,
127.4, 127.0, 125.3, 28.9, 28.2, 27.3, 25.8, 21.4, 21.3. IR (KBr) t 3033 (w), 2949
(w), 2839 (w), 1660 (m), 1587 (s), 1506 (w), 1444 (w), 1387 (m), 1293 (m), 1222
(m), 1181 (w), 1126 (w), 1027 (w), 877 (m), 736 (s) cmꢁ1. MS (m=z): 373.67.
1
Compound 4c. Yield 75%, mp 200.0–201.8 ꢀC. H NMR (600 MHz, CDCl3)
d 8.49 (d, 2H, J ¼ 7.8 Hz, ArH), 7.40 (d, 2H, J ¼ 8.4 Hz, ArH), 7.34 (t, 2H,
J ¼ 7.2 Hz, ArH), 7.25 (t, 2H, J ¼ 7.2 Hz, ArH), 7.13 (d, 2H, J ¼ 7.2 Hz, ArH),
7.08 (d, 2H, J ¼ 8.4 Hz, ArH), 2.76 (t, 4H, J ¼ 7.2 Hz, 2CH2), 2.56 (t, 4H, J ¼ 7.8 Hz,
Hz, 2CH2). 13C NMR (600 MHz, CDCl3) d 150.2, 146.2, 137.7, 136.3, 135.2, 133.7,
131.0, 130.1, 128.9, 128.8, 128.6, 128.2, 127.6, 127.5, 127.1, 127.0, 125.3, 63.7, 28.1,
25.8. IR (KBr) t 3035 (w), 2926 (w), 1597 (w), 1545 (m), 1488 (m), 1386 (vs), 1225
(w), 1168 (w), 1088 (m), 1014 (w), 944 (w), 833 (m), 735 (s) cmꢁ1. MS (m=z): 393.87.
1
Compound 4d. Yield 71%, mp 187.9–188.6 ꢀC. H NMR (600 MHz, CDCl3)
d 8.62 (d, 2H, J ¼ 7.8 Hz, ArH), 7.44 (t, 2H, J ¼ 7.8 Hz, ArH), 7.34 (t, 2H, J ¼ 7.2 Hz,
ArH), 7.23 (d, 2H, J ¼ 7.2 Hz, ArH), 7.15 (d, 2H, J ¼ 8.4 Hz, ArH), 7.05 (d, 2H,
J ¼ 8.4 Hz, ArH), 3.91 (s, 3H, OCH3), 2.87–2.85 (m, 4H, 2CH2), 2.72–2.69 (m,
4H, 2CH2). 13C NMR (600 MHz, CDCl3) d 159.1, 150.1, 147.3, 137.8, 135.5,
130.0, 129.9, 129.2, 128.6, 127.4, 127.0, 125.3, 114.0, 55.3, 28.2, 25.9. IR (KBr) t
3033 (w), 2919 (w), 2833 (w), 1608 (m), 1548 (w), 1510 (s), 1427 (w), 386 (s), 1291
(m), 1241 (s), 1173 (m), 1033 (w), 838 (m), 806 (w), 735 (m), 660 (w), 515 (w) cmꢁ1
.
MS (m=z): 389.53.
Compound 4e. Yield 64%, mp > 250 ꢀC. 1H NMR (600 MHz, CDCl3) d 9.28
(s, 1H, OH), 8.57 (d, 2H, J ¼ 7.8 Hz, ArH), 7.40 (t, 2H, J ¼ 7.2 Hz, ArH), 7.31 (t, 2H,
J ¼ 7.2 Hz, ArH), 7.21 (d, 2H, J ¼ 7.2 Hz, ArH), 7.04 (d, 2H, J ¼ 8.4 Hz, ArH),
6.72–6.68 (m, 2H, ArH), 3.89 (s, 3H, OCH3), 2.84 (t, 4H, J ¼ 7.2 Hz, CH2), 2.70
(t, 4H, J ¼ 7.2 Hz, CH2). 13C NMR (600 MHz, CDCl3) d 150.1, 147.4, 146.7,
145.1, 137.8, 135.4, 129.8, 129.1, 128.6, 127.4, 127.0, 125.3, 121.7, 114.6, 111.2,
56.1, 28.2, 25.8. IR (KBr) t 3444 (w), 2926 (w), 2836 (w), 2345 (w), 1604 (w), 1543
(w), 1512 (s), 1464 (w), 1416 (w), 1387 (m), 1266 (m), 1238 (w), 1193 (m), 1120
(w), 1021 (w), 750 (m) cmꢁ1. MS (m=z): 405.53.

ONE-POT MULTICOMPONENT CONDENSATION
849
Supporting Information
Crystallographic data (CCDC-628460 for 3g, CCDC-618867 for 4c) have been
deposited at the Cambridge Crystallographic Database Centre.
ACKNOWLEDGMENTS
This work was financially supported by the National Natural Science Foun-
dation of China (Grant No. 20672091), China. We are grateful to Ms. Min Shao
for assistance with measuring the x-ray single-crystal structures.
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