An efficient method for the synthesis of naphtho[2,3-f]pyrano[3,4-c] quinoline derivatives catalyzed by iodine

Article abstract of DOI:10.1002/jhet.1606

A mild and efficient method for the synthesis of naphtho[2,3-f]pyrano[3,4- c]quinoline derivatives via three-component reaction of aromatic aldehyde, anthracen-2-amine, and tetrahydropyran-4-one is described using iodine as catalyst. The features of this procedure are mild reaction conditions, good to high yields, and operational simplicity.

Full text of DOI:10.1002/jhet.1606

January 2014
An Efficient Method for the Synthesis of Naphtho[2,3-f]pyrano[3,4-c]
175
quinoline Derivatives Catalyzed by Iodine
a
b
a
*
W. Wang, M.-M. Zhang, and X.-S. Wang
aSchool of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional
Materials, Jiangsu Normal University, Jiangsu 221116, China
bThe Key Laboratory of Biotechnology on Medical Plant of Jiangsu Province, Jiangsu Normal University, Jiangsu
221116, China
*
E-mail: xswang1974@yahoo.com
Received October 3, 2011
DOI 10.1002/jhet.1606
Published online 28 October 2013 in Wiley Online Library (wileyonlinelibrary.com).
O
O
NH2
I2
THF
+
ArCHO
+
O
N
Ar
A mild and efficient method for the synthesis of naphtho[2,3-f]pyrano[3,4-c]quinoline derivatives via
three-component reaction of aromatic aldehyde, anthracen-2-amine, and tetrahydropyran-4-one is described
using iodine as catalyst. The features of this procedure are mild reaction conditions, good to high yields, and
operational simplicity.
J. Heterocyclic Chem., 51, 175 (2014).
INTRODUCTION
Table 1. It was found that no reaction occurred at reflux con-
dition in the absence of iodine (Table 1, entry 1), and the
yield of 4a was much greater in the presence of various quan-
tities of the iodine, reaching a maximum of 89% yield with
5 mol% iodine (Table 1, entries 4–6). The yield of 4a was
also dependent on temperature (entries 2–4), proceeding
smoothly at reflux in THF. Different solvents were also
tested, and THF appeared to be the best medium for this
transformation (entry 4 vs. 7–10).
Quinoline derivatives are a very interesting class of hetero-
cyclic system because the quinoline ring is an essential core
moiety in a variety of natural and synthetic biologically active
compounds [1]. In particular for polycyclic skeletons contain-
ing quinoline ring, for example, pyranoquinoline has been
reported to possess antimicrobial [2], anticancer [3], selective
human acetylcholinesterase inhibitory [4], antibacterial [5],
and anti-inflammatory properties [6]. In addition, naphthoqui-
noline derivatives are also an important class of heterocycles
with various bioactivities [7].
To the best of our knowledge, there are no literatures
concerning about the synthesis of pentacyclic ring system
of naphtho[2,3-f]pyrano[3,4-c]quinoline, which contains
both naphthalene, pyran, and quinoline rings; this novel
interesting skeleton may possess potential bioactive for
screening. Thus, simple and efficient method to synthesize
naphthopyranoquinoline would be attractive.
This process could tolerate both electron-donating, such
as alkyl and alkoxyl, and electron-withdrawing (halogen)
substituents on the aromatic aldehydes (Table 2). In all
cases, the reactions proceeded efficiently at reflux in THF
to afford the corresponding naphtho[2,3-f]pyrano[3,4-c]
quinolines in good to high yields. Alkylaldehydes, such
as propyl aldehyde, n-butyl aldehyde, and n-heptaldehyde,
were also selected as reactants to react with 2 and 3. How-
ever, they all gave a mixture and were difficult to separate
1
and purify. All the compounds were characterized by H
As a continuation of our research devoted to the develop-
ment of new methods for the preparation of polycyclic
heterocycles catalyzed by iodine [8], herein, we would like
to synthesize 5-aryl-2,4-dihydro-1H-naphtho[2,3-f]pyrano
[3,4-c]quinoline derivatives in THF catalyzed by iodine.
NMR, IR, and HRMS, and the analytical data are all in
good agreement with the proposed structures.
According to the literatures [9], we think that iodine cat-
alyzes the reaction as a mild Lewis acid. The mechanism
was tentatively proposed as shown in Scheme 2. In the pres-
ence of iodine, tetrahydropyran-4-one is in equilibrium
with its enol form [9b]. The Schiff base I may be formed
by the reaction of aromatic aldehyde and anthracen-2-
amine firstly. And then, imino-Diels-Alder reaction be-
tween the iodine-activated Schiff base II and enol takes
place selectively to form the intermediate III for its stability.
The dehydration of III results in dihydronaphtho[2,3-f]pyrano
[3,4-c]quinoline IV, which is further oxidized by air to afford
aromatized final products 4.
RESULTS AND DISCUSSION
Treatment of aromatic aldehyde 1 and anthracen-2-amine
2 with tetrahydropyran-4-one 3 in THF in the presence of
5mol% iodine at reflux condition afford 5-aryl-2,4-dihydro-
1H-naphtho[2,3-f]pyrano[3,4-c]quinoline derivatives in high
yields (Scheme 1).
Using the conversion of 4-chlorobenzaldehyde 1a, 2, and
3 as a model, several parameters were explored as shown in
© 2013 HeteroCorporation

176
W. Wang, M.-M. Zhang, and X.-S. Wang
Vol 51
Scheme 1. The synthetic route of the products 4.
Scheme 2. The possible mechanism for the formation of products 4.
OH
O
O
I2
O
NH2
I2
O
O
+
ArCHO
+
Ar
THF
O
N
Ar
NH2
N
I2
-H2O
ArCHO
+
1
2
3
4
I
Table 1
HO
Synthetic results of 4a under different reaction conditions.a
OH
-H2O
O
Air
4
N
imino-Diels-Alder
Reaction
N
O
I2
N
O
Isolated
yields (%)
Entry
Temp. (ꢀC)
I2 (mol%)
Solvent
Ar
Ar
Ar
II
IV
III
1
2
3
4
5
6
7
8
9
10
Reflux
RT
50
Reflux
Reflux
Reflux
Reflux
Reflux
80
0
5
5
5
1
10
5
5
5
5
THF
THF
THF
THF
THF
THF
CH3CN
Benzene
DMF
CHCl3
0
trace
72
89
78
88
82
83
76
EXPERIMENTAL
Melting points were determined in open capillaries and were
uncorrected. IR spectra were recorded on a Tensor 27 spectrometer
in KBr pellet. H NMR spectra was obtained from a solution in
DMSO-d6 or CDCl3 with Me4Si as internal standard using a
Bruker-400 spectrometer. HRMS analyses were carried out using a
Bruker-micro-TOF-Q-MS analyzer (Bruker Corporation, Karlsruhe,
Germany). All of the reagents were purchased from China National
Pharmaceutical Group Corporation (Shanghai, China); the solvent
1
Reflux
82
aReagents and conditions: 4-chlorobenzaldehyde 1a (0.140 g, 1.0 mmol),
2 (0.193 g, 1.0 mmol), 3 (0.105 g, 1.05 mmol), solvent (10 mL).
Table 2
of THF was dried by Na and redistilled before use.
Synthetic results of 4 catalyzed by iodine in THF.a
General procedure for the synthesis of 5-aryl-2,4-dihydro-
1H-naphtho[2,3-f]pyrano[3,4-c]quinolines 4.
A dry 50mL
flask was charged with aromatic aldehyde (1.0 mmol), anthracen-
2-amine (0.193 g, 1.0 mmol), tetrahydropyran-4-one (0.105 g,
1.05 mmol), I2 (0.05mmol, 0.013g), and THF (10mL). The
reaction mixture was stirred at reflux for 6–13 h, and then, a small
amount of DMF was added to the mixture, until all the precipitate
was dissolved. The products 4 were obtained by filtration, when
the mixture was allowed to cool down to room temperature.
5-(4-Chlorophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-
c]quinoline 4a. m.p. 259–261ꢀC; 1H NMR (CDCl3, 400 MHz):
dH 3.85 (s, 2H, CH2), 4.07 (d, J = 5.2Hz, 2H, CH2), 4.94 (s, 2H,
CH2), 7.52 (s, 4H, ArH), 7.63–7.65 (m, 2H, ArH), 7.86 (d,
J = 9.2 Hz, 1H, ArH), 8.03 (d, J = 9.2 Hz, 1H, ArH), 8.09–8.17
(m, 2H, ArH), 8.46 (s, 1H, ArH), 9.22 (s, 1H, ArH). IR (KBr,
cmÀ1): n 3050, 2966, 2944, 2850, 1552, 1534, 1492, 1476, 1433,
1422, 1365, 1312, 1249, 1223, 1160, 1136, 1107, 1090, 1034,
1015, 979, 955, 890, 878, 829, 739. HRMS (ESI, m/z): Calcd for
C26H19ClNO [M +H]+ 396.1155, found 396.1152.
Isolated
yields (%)
Entry
Ar
Products
Time (h)
1
2
3
4
5
6
7
8
4-ClC6H4
4a
4b
4c
4d
4e
4f
4g
4h
4i
8
13
12
8
89
92
83
87
90
85
93
90
82
87
88
90
4-CH3OC6H4
3,4-(CH3)2C6H3
3-ClC6H4
3,4-Cl2C6H3
3,4-(CH3O)2C6H3
3-CH3OC6H4
2-ClC6H4
4-FC6H4
2-BrC6H4
3-BrC6H4
Piperonyl
6
12
10
10
8
12
12
10
9
10
11
12
4j
4k
4l
aReagents and conditions: 1 (1.0 mmol), 2 (0.193 g, 1.0 mmol), 3 (0.105 g,
1.05 mmol), I2 (0.05 mmol, 0.013 g), THF (10 mL), reflux.
5-(4-Methoxyphenyl)-2,4-dihydro-1H-naphtho[2,3-f]
pyrano[3,4-c]quinoline 4b.
m.p. 234–235ꢀC; 1H NMR
(CDCl3, 400 MHz): dH 3.83 (t, J = 5.2 Hz, 2H, CH2), 3.89 (s,
3H, CH3O), 4.06 (t, J = 5.2 Hz, 2H, CH2), 4.96 (s, 2H, CH2),
7.04 (d, J = 8.8 Hz, 2H, ArH), 7.51 (d, J = 8.4 Hz, 2H, ArH),
7.59–7.63 (m, 2H, ArH), 7.88 (d, J = 9.2 Hz, 1H, ArH), 8.00
(d, J = 9.2 Hz, 1H, ArH), 8.07–8.09 (m, 1H, ArH), 8.12–8.15
(m, 1H, ArH), 8.44 (s, 1H, ArH), 9.20 (s, 1H, ArH). IR (KBr,
cmÀ1): n 2970, 2934, 2840, 1606, 1560, 1531, 1513, 1474,
1424, 1366, 1289, 1242, 1178, 1147, 1108, 1030, 981, 898,
876, 833, 747. HRMS (ESI, m/z): Calcd for C27H21NO2Na
[M + Na]+ 414.1470, found 414.1484.
CONCLUSION
In conclusion, we found a mild and efficient method for the
synthesis of 5-aryl-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-
c]quinoline derivatives via three-component reaction of
aromatic aldehyde, anthracen-2-amine, and tetrahydropyran-
4-one using iodine as catalyst. The features of this procedure
are mild reaction conditions, good to high yields, and opera-
tional simplicity.
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

January 2014
Synthesis of Naphtho[2,3-f]pyrano[3,4-c]quinoline Derivatives
177
ArH). IR (KBr, cmÀ1): n 3052, 2937, 2899, 2858, 1553, 1537, 1471,
1425, 1364, 1309, 1289, 1271, 1245, 1160, 1139, 1102, 1076, 1047,
1034, 970, 952, 894, 824, 763, 741, 709. HRMS (ESI, m/z): Calcd
for C26H19ClNO [M + H]+ 396.1155, found 396.1289.
5-(p-Tolyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-c]
1
quinoline 4c. m.p. 225–226ꢀC; H NMR (CDCl3, 400 MHz):
dH 2.44 (s, 3H, CH3), 3.83 (t, J = 5.2 Hz, 2H, CH2), 4.06 (t,
J = 5.2 Hz, 2H, CH2), 4.95 (s, 2H, CH2), 7.32 (d, J = 8.0 Hz, 2H,
ArH), 7.44 (d, J = 8.0 Hz, 2H, ArH), 7.59–7.63 (m, 2H, ArH),
7.87 (d, J = 9.2 Hz, 1H, ArH), 7.99 (d, J = 8.8 Hz, 1H, ArH),
8.07–8.09 (m, 1H, ArH), 8.12–8.15 (m, 1H, ArH), 8.43 (s, 1H,
ArH), 9.21 (s, 1H, ArH). IR (KBr, cmÀ1): n 3046, 2937, 2851,
1548, 1531, 1472, 1421, 1364, 1325, 1304, 1247, 1185, 1147,
1108, 1033, 1019, 980, 892, 828, 747. HRMS (ESI, m/z): Calcd
for C27H21NONa [M + Na]+ 398.1521, found 398.1531.
5-(4-Fluorophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano
[3,4-c]quinoline 4.
m.p. 271–274ꢀC; 1H NMR (CDCl3,
400 MHz): dH 3.83 (t, J = 5.2 Hz, 2H, CH2), 4.06 (t,
J = 5.2 Hz,2H, CH2), 4.91 (s, 2H, CH2), 7.19–7.23 (m, 2H,
ArH), 7.52–7.63 (m, 4H, ArH), 7.85 (d, J = 9.2 Hz, 1H, ArH),
8.01 (d, J = 9.2 Hz, 1H, ArH), 8.07–8.15 (m, 2H, ArH), 8.44 (s,
1H, ArH), 9.20 (s, 1H, ArH). IR (KBr, cmÀ1): n 3048, 2987,
2936, 2902, 2850, 1602, 1534, 1509, 1470, 1434, 1322, 1363,
1305, 1217, 1157, 1107, 1079, 1033, 1017, 978, 956, 898,
877, 833, 791, 739. HRMS (ESI, m/z): Calcd for C26H19FNO
[M + H]+ 380.1451, found 380.1475.
5-(2-Bromophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-
c]quinoline 4j. m.p. 218–220ꢀC; 1H NMR (CDCl3, 400MHz): dH
3.77–3.92 (m, 2H, CH2), 3.98–4.04 (m, 1H, CH), 4.08–4.14 (m, 1H,
CH), 4.62–4.83 (m, 2H, CH2), 7.32–7.41 (m, 2H, ArH), 7.46–7.50
(m, 1H, ArH), 7.60–7.65 (m, 2H, ArH), 7.72 (d, J= 8.0 Hz, 1H,
ArH), 7.87 (d, J= 9.2 Hz, 1H, ArH), 8.02 (d, J= 8.8 Hz, 1H, ArH),
8.08–8.16 (m, 2H, ArH), 8.45 (s, 1H, ArH), 9.23 (s, 1H, ArH). IR
(KBr, cmÀ1): n 3048, 2935, 2868, 2835, 1558, 1536, 1469, 1422,
1364, 1313, 1247, 1221, 1161, 1135, 1104, 1078, 1042, 1026, 977,
956, 883, 822, 762, 747, 730. HRMS (ESI, m/z): Calcd for
C26H19BrNO [M + H]+ 440.0650, found 440.0654.
5-(3-Bromophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-
c]quinoline 4k. m.p. 225–226ꢀC; 1H NMR (CDCl3, 400MHz):
dH 3.84 (t, J = 5.2 Hz, 2H, CH2), 4.06 (t, J = 5.2 Hz, 2H, CH2),
4.92 (s, 2H, CH2), 7.37–7.41 (m, 1H, ArH), 7.48 (d, J = 7.6Hz,
1H, ArH), 7.60–7.65 (m, 3H, ArH), 7.72 (s, 1H, ArH), 7.85 (d,
J = 9.2 Hz, 1H, ArH), 8.02 (d, J = 9.2Hz, 1H, ArH), 8.08–8.15 (m,
2H, ArH), 8.45 (s, 1H, ArH), 9.21 (s, 1H, ArH). IR (KBr, cmÀ1):
n 3050, 2962, 2843, 1591, 1553, 1531, 1472, 1432, 1407, 1358,
1312, 1291, 1250, 1161, 1136, 1110, 1069, 1037, 997, 982, 955,
898, 875, 809, 792, 742, 704. HRMS (ESI, m/z): Calcd for
C26H19BrNO [M + H]+ 440.0650, found 440.0693.
5-Piperonyl-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-c]
quinoline 4l. m.p. 235–238ꢀC; 1H NMR (CDCl3, 400 MHz): dH
3.8 (s, 2H, CH2), 4.06 (s, 2H, CH2), 4.96 (s, 2H, CH2), 6.04 (s, 2H,
CH2), 6.94 (d, J = 8.0 Hz, 1H, ArH), 7.01–7.05 (m, 2H, ArH), 7.61
(d, J = 5.2 Hz, 2H, ArH), 7.85 (d, J = 9.2 Hz, 1H, ArH), 7.99 (d,
J = 9.2Hz, 1H, ArH), 8.08 (d, J = 5.2 Hz, 1H, ArH), 8.13 (d,
J = 5.2Hz, 1H, ArH), 8.43 (s, 1H, ArH), 9.20 (s, 1H, ArH). IR
(KBr, cmÀ1): n 3052, 2956, 2931, 2878, 1551, 1536, 1499, 1476,
1433, 1357, 1305, 1233, 1179, 1164, 1141, 1116, 1082, 1042,
978, 941, 896, 872, 861, 801, 733. HRMS (ESI, m/z): Calcd for
C27H20NO3 [M + H]+ 406.1443, found 406.1427.
5-(3-Chlorophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano
[3,4-c]quinoline 4d.
m.p. 213–214ꢀC; 1H NMR (CDCl3,
400 MHz): dH 3.83 (t, J= 5.2 Hz, 2H, CH2), 4.06 (t, J= 5.2 Hz, 2H,
CH2), 4.92 (s, 2H, CH2), 7.42–7.46 (m, 3H, ArH), 7.56 (s, 1H, ArH),
7.60–7.65 (m, 2H, ArH), 7.85 (d, J= 8.8 Hz, 1H, ArH), 8.01 (d,
J= 9.2 Hz, 1H, ArH), 8.07–8.10 (m, 1H, ArH), 8.13–8.15 (m, 1H,
ArH), 8.44 (s, 1H, ArH), 9.21 (s, 1H, ArH). IR (KBr, cmÀ1): n 3044,
2967, 2945, 2882, 2831, 1596, 1570, 1548, 1533, 1475, 1435, 1419,
1383, 1353, 1325, 1306, 1248, 1163, 1139, 1111, 1083, 1058, 1036,
981, 950, 901, 884, 873, 837, 819, 788, 739, 722, 703. HRMS (ESI,
m/z): Calcd for C26H19ClNO [M + H]+ 396.1155, found 396.1200.
5-(3,4-Dichlorophenyl)-2,4-dihydro-1H-naphtho[2,3-f]
pyrano[3,4-c]quinoline 4e.
m.p. 242–243ꢀC; 1H NMR
(CDCl3, 400 MHz): dH 3.83 (t, J = 5.2 Hz, 2H, CH2), 4.06 (t,
J = 5.2 Hz, 2H, CH2), 4.92 (s, 2H, CH2), 7.39–7.41 (m, 1H,
ArH), 7.58–7.65 (m, 3H, ArH), 7.69 (d, J = 2.0 Hz, 1H, ArH),
7.82 (d, J = 9.2 Hz, 1H, ArH), 8.02 (d, J = 9.2 Hz, 1H, ArH),
8.08–8.15 (m, 2H, ArH), 8.45 (s, 1H, ArH), 9.20 (s, 1H, ArH).
IR (KBr, cmÀ1): n 3048, 2947, 2880, 2848, 1556, 1533, 1472,
1433, 1378, 1353, 1307, 1248, 1140, 1110, 1028, 982, 949,
905, 882, 873, 829, 808, 791, 734, 710. HRMS (ESI, m/z):
Calcd for C26H18Cl2NO [M + H]+ 430.0765, found 430.0793.
5-(3,4-Dimethoxyphenyl)-2,4-dihydro-1H-naphtho[2,3-f]
pyrano[3,4-c]quinoline 4f. m.p. 233–235ꢀC; 1H NMR (CDCl3,
400 MHz): dH 3.86 (t, J= 5.2 Hz, 2H, CH2), 3.95 (s, 3H, CH3O),
3.96 (s, 3H, CH3O), 4.07 (m, J=5.2Hz, 2H, CH2), 4.98 (s, 2H,
CH2), 7.00 (d, J= 8.8 Hz, 1H, ArH), 7.10 (d, J= 6.8 Hz, 2H, ArH),
7.60–7.63 (m, 2H, ArH), 7.88 (d, J= 9.2 Hz, 1H, ArH), 8.00 (d,
J= 9.2 Hz, 1H, ArH), 8.07–8.15 (m, 2H, ArH), 8.44 (s, 1H, ArH),
9.21 (s, 1H, ArH). IR (KBr, cmÀ1): n 3057, 2997, 2946, 2877,
2817, 1586, 1515, 1476, 1462, 1473, 1362, 1313, 1252, 1229, 1181,
1142, 1102, 1029, 970, 895, 881, 811, 750, 700. HRMS (ESI, m/z):
Calcd for C28H23NO3Na [M + Na]+ 444.1576, found 444.1588.
5-(3-Methoxyphenyl)-2,4-dihydro-1H-naphtho[2,3-f]
pyrano[3,4-c]quinoline 4g. m.p. 214–215ꢀC; 1H NMR (CDCl3,
400 MHz): dH 3.84 (t, J= 5.2 Hz,2H, CH2), 3.88 (s, 3H, CH3O),
4.06 (t, J= 5.2 Hz, 2H, CH2), 4.94 (s, 2H, CH2), 7.00–7.03 (m,
1H, ArH), 7.08–7.11 (m, 2H, ArH), 7.40–7.44 (m, 1H, ArH),
7.59–7.64 (m, 2H, ArH), 7.88 (d, J= 9.2 Hz, 1H, ArH), 8.00 (d,
J= 9.2 Hz, 1H, ArH), 8.07–8.15 (m, 2H, ArH), 8.44 (s, 1H,
ArH), 9.21 (s, 1H, ArH). IR (KBr, cmÀ1): n 3048, 2969, 2934,
2870, 2838, 1589, 1536, 1477, 1464, 1426, 1363, 1318, 1269,
1242, 1184, 1160, 1105, 1080, 1033, 982, 969, 882, 826, 796,
739, 713. HRMS (ESI, m/z): Calcd for C27H21NO2Na [M + Na]+
414.1470, found 414.1509.
Acknowledgments. We are grateful to the National Natural Science
foundation of China (20802061), the Priority Academic Program
Development of Jiangsu Higher Education Institutions, Qing Lan
Project (08QLT001, 10QLD008) of Jiangsu Education Committee,
and Graduate Foundation of Jiangsu Normal University for
financial support.
5-(2-Chlorophenyl)-2,4-dihydro-1H-naphtho[2,3-f]pyrano[3,4-
c]quinoline 4h. m.p. 223–224ꢀC; 1H NMR (CDCl3, 400 MHz): dH
3.77–3.90 (m, 2H, CH2), 3.99–4.13 (m, 2H, CH2), 4.64–4.85 (m, 2H,
CH2), 7.39–7.44 (m, 3H, ArH), 7.52–7.54 (m, 1H, ArH), 7.60–7.65
(m, 2H, ArH), 7.87 (d, J= 9.2 Hz, 1H, ArH), 8.01 (d, J= 9.2 Hz, 1H,
ArH), 8.07–8.16 (m, 2H, ArH), 8.45 (s, 1H, ArH), 9.22 (s, 1H,
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Journal of Heterocyclic Chemistry
DOI 10.1002/jhet