Poly(4-vinylpyridinium butane sulfonic acid) hydrogen sulfate: An efficient, heterogeneous poly(ionic liquid), solid acid catalyst for the one-pot preparation of 1-amidoalkyl-2-naphthols and substituted quinolines under solvent-free conditions

Article abstract of DOI:10.1016/S1872-2067(12)60659-7

Poly(4-vinylpyridinium butane sulfonic acid) hydrogen sulfate has been used as an efficient dual acidic catalyst for the one-pot preparation of 1-amidoalkyl-2-naphthols and substituted quinolines under solvent-free conditions. The catalyst was characteriz

Full text of DOI:10.1016/S1872-2067(12)60659-7

Chinese Journal of Catalysis 34 (2013) 1861–1868
a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / c h n j c
Article
Poly(4‐vinylpyridinium butane sulfonic acid) hydrogen sulfate: An
efficient, heterogeneous poly(ionic liquid), solid acid catalyst for the
one‐pot preparation of 1‐amidoalkyl‐2‐naphthols and substituted
quinolines under solvent‐free conditions
Ali Reza Kiasat*, Arash Mouradzadegun, Seyyed Jafar Saghanezhad
Chemistry Department, College of Science, Shahid Chamran University, P. O. Box 61357‐4‐3169, Ahvaz, Iran
A R T I C L E I N F O
A B S T R A C T
Article history:
Poly(4‐vinylpyridinium butane sulfonic acid) hydrogen sulfate has been used as an efficient dual
acidic catalyst for the one‐pot preparation of 1‐amidoalkyl‐2‐naphthols and substituted quinolines
under solvent‐free conditions. The catalyst was characterized by Fourier transform infrared spec‐
troscopy, scanning electron microscopy, and thermo‐gravimetric analysis. The results revealed
several advantages to our new catalyst system, including its reusability, facile work‐up procedure,
eco‐friendly reaction conditions, short reaction time, and high product yields.
Received 6 June 2013
Accepted 10 July 2013
Published 20 October 2013
Keywords:
Solvent‐free
β‐Naphthol
© 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences.
Published by Elsevier B.V. All rights reserved.
Poly(ionic liquid)
Acetamide
Quinoline
2‐Aminobenzophenone
1. Introduction
ers throughout the world, most notably from the perspective of
green chemistry [3]. The synergic effect of performing conden‐
Poly(ionic liquid)s (PILs) have emerged as new materials
with a wide variety of potential application in a number of dif‐
ferent fields, including energy and environmental research,
analytical chemistry, materials science, biotechnology, surface
science, and catalyst development [1]. There are several ad‐
vantages associated with the use of PILs over ionic liquids (ILs),
including enhanced mechanical stability, improved processa‐
bility, durability, and spatial controllability. Two basic strate‐
gies have been reported for the synthesis of PILs, including (1)
the direct polymerization of IL monomers, and (2) the chemical
modification of existing polymers [2].
sation reactions under solvent‐free conditions with a hetero‐
geneous catalyst could enhance their efficiency from an eco‐
nomic as well as an ecological point of view [4,5]. The applica‐
tion of such as eco‐friendly, solvent‐free approach effectively
opens up numerous possibilities for conducting rapid organic
syntheses and functional group transformations more effi‐
ciently [6].
1‐Amidoalkyl‐2‐naphthol derivatives have been identified
as compounds of considerable interest because they possess a
broad range of biological, medicinal, and pharmacological ac‐
tivity [7–13]. Given the importance of these compounds, con‐
siderable research efforts have been devoted to the develop‐
ment of multi‐component reactions (MCRs) for the synthesis of
Organic reactions conducted under solvent‐free conditions
have attracted considerable levels of attention from research‐
*Corresponding author. Tel/Fax: +98‐611‐3331746; E‐mail: akiasat@scu.ac.ir
This work was supported by Shahid Chamran University.
DOI: 10.1016/S1872‐2067(12)60659‐7 | http://www.sciencedirect.com/science/journal/18722067 | Chin. J. Catal., Vol. 34, No. 10, October 2013

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
1‐amidoalkyl‐2‐naphthols from aldehydes, β‐naphthols, and
tored by TLC on silica gel polygram SILG/UV 254 plates. Infra‐
red (IR) spectra were recorded on a BOMEM MB‐Series 1998
Fourier transform infrared spectrophotometer as KBr pellets in
the range of 4000–400 cm−1. 1H and 13C NMR spectra were rec‐
orded in CDCl3 or DMSO‐d6 on a Bruker Advanced DPX 400
MHz spectrometer using TMS as an internal reference. The
thermal stability of the supported catalyst was examined using
a BÄHR SPA 503 thermo‐gravimetric analyzer at a heating rate
of 10 °C/min over a temperature range of 40–950 °C. Scanning
electron microscopy analyses were carried out using a LEO
1455VP scanning electron microscope, operating at 1–30 kV.
Elemental analyses were conducted on an ECS 4010 Costech
elemental combustion system.
amides under a range of different reaction conditions using a
variety of different catalysts, including montmorillonite K10
[14], iodine [15], Fe(HSO4)3 [16], K5CoW12O40·3H2O [17], sul‐
famic acid [18], and thiamine hydrochloride [19].
Of the many different methodologies reported for the prep‐
aration of quinolines, the Friedländer reaction is still one of the
most straightforward protocols, and this reaction has recently
been reviewed in some detail [20]. The Friedländer synthesis
involves a condensation reaction followed by a cyclodehydra‐
tion reaction between an aromatic 2‐aminoaldehyde or ketone
and an aldehyde or ketone possessing an α‐activated meth‐
ylene group [21]. Although various catalysts have been pro‐
posed for the Friedländer annulation reaction, acidic catalysts
have been shown to be superior to basic catalysts for this
transformation [22]. As well as acidic catalysts such as
Brönsted acids [23–27] and Lewis acids [28–30], ionic liquids
[31] and a range of catalysts [32,33] have also been reported to
promote this reaction.
In a continuation of our efforts towards the synthesis of new
solid acid catalysts and their subsequent application in organic
synthesis [34,35], we recently synthesized poly(4‐vinylpyri‐
dinium butane sulfonic acid) hydrogen sulfate, P(4VPBSA)‐
HSO4, as a novel dual acidic PIL heterogeneous catalyst for the
one‐pot preparation of 1,8‐dioxo‐octahydro‐xanthenes under
solvent‐free conditions [36]. To further expand upon the po‐
tential applications of this catalyst, herein we describe our
most recent work towards exploring the catalytic activity of
this catalyst in the one‐pot preparation of amidoalkyl naphthols
(Scheme 1) and substituted quinolines (Scheme 2) under sol‐
vent‐free conditions.
2.2. General procedure for the preparation of the catalyst
1,4‐Butane sultone (2.72 g, 20 mmol) was slowly added to a
dispersion of poly(4‐vinylpyridine) (2.1 g) in toluene at ambi‐
ent temperature, and the resulting mixture was stirred for 2 h.
The temperature was then raised to 70 °C and the mixture was
stirred for 24 h. The mixture was then cooled to ambient tem‐
perature and the resulting solid was filtered. The filter‐cake
was then washed sequentially with dichloromethane and
methanol before being dried under vacuum at 55 °C. The dried
white solid (3.1 g) was dispersed in 15 mL of H2O in a 50 mL
round bottom flask, and excess sulfuric acid was then added
into the flask in a drop‐wise manner at ambient temperature.
Upon completion of the addition, the mixture was stirred for 12
h at ambient temperature. The resulting cream‐colored solid
was washed several times with deionized water before being
dried under vacuum at 55 °C for 24 h. Subsequent elemental
analysis of the catalyst revealed that the CHNS percentages
were as follows: N 6.83%, C 48.47%, H 6.11%, and S 12.74%.
2. Experimental
2.1. General
2.3. Determination of the acidity of the catalyst
All of the commercially available chemicals were purchased
from Fluka and Merck and used without further purification.
Poly(4‐vinyl pyridine) cross‐linked with 2% DVB (100–200
mesh, MW: 60000) was purchased from Fluka. All of the prod‐
ucts were characterized for their physical properties and by
comparison with authentic samples. The reactions were moni‐
To determine the acidity of the catalyst, P(4VPBSA)HSO4 (20
mg) was added to a 25 mL aqueous solution of NaCl (1 mol/L,
pH = 6.64), and the resulting mixture was stirred for 2 h. The
pH of the solution was reduced to 2.81, indicating the presence
of 1.94 mmol/g of H+.
H3C
O
R
NH
OH
O
CHO
OH
P(4VPBSA)HSO4
Solvent-free, 110 oC
CH3
H3N
R
3
1
2a-j
4a-j
Scheme 1. One‐pot preparation of amidoalkyl naphthols.
R
R
R2
R2
R1
X
O
P(4VPBSA)HSO4
Solvent-free, 110 oC
O
NH2
R1
6a-j
N
5a: X = H, R = Ph
5b: X = Cl, R = Ph
7a-j
Scheme 2. One‐pot preparation of substituted quinolones.

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
2.4. Typical procedure for the preparation of the
1‐amidoalkyl‐2‐naphthols
Hz, 1H), 8.00 (d, J = 7.0 Hz, 1H), 8.50 (s, 1H), 9.75 (s, 1H); 13C
NMR (100 MHz, DMSO‐d6): δ 22.3, 47.5, 117.0, 118.5, 122.1,
122.7, 126.1, 126.2, 127.9, 128.2, 128.4, 129.1, 129.2, 129.7,
132.1, 132.7, 139.7, 153.5, 168.4.
A mixture of aromatic aldehyde (1.0 mmol), β‐naphthol (1.0
mmol), acetamide (1.2 mmol), and P(4VPBSA)HSO4 (0.05 g, 10
mol%) was stirred for 10–20 min under solvent‐free conditions
at 110 °C. Upon completion of the reaction by TLC (ethyl ace‐
tate/n‐hexane (2:5, v/v) eluent), the insoluble crude product
was dissolved in hot ethanol and the P(4VPBSA)HSO4 was re‐
moved by filtration. The desired product subsequently precipi‐
tated from the filtrate on cooling and was collected by filtration
in high purity. Further purification could be achieved as neces‐
sary by recrystallization of this material from aqueous ethanol.
3,3‐Dimethyl‐9‐phenyl‐3,4‐dihydroacridin‐1(2H)‐one (Ta‐
ble 3, Entry 5, 7e). IR (KBr, cm–1): 3077, 2954, 2866, 1697,
1
1555, 1477, 1384; H NMR (CDCl3, 400 MHz): δ 1.16 (s, 6H),
2.56 (s, 2H), 3.27 (s, 2H), 7.17 (d, 2H, J = 6.5 Hz), 7.40 (t, 1H, J =
7.5 Hz), 7.47–7.50 (m, 4H), 7.75 (t, 1H, J = 7.0 Hz), 8.06 (d, 1H, J
= 8.5 Hz); 13C NMR (100 MHz, DMSO d6): δ 28.3, 32.8, 47.8, 53.8,
126.0, 127.1, 127.7, 127.9, 128.3, 128.6, 128.7, 128.9, 131.3,
132.1, 134.6, 137.8, 148.7, 150.1, 161.6, 197.7.
Ethyl 6‐chloro‐2‐methyl‐4‐phenylquinoline‐3‐carboxylate
(Table 3, Entry 7, 7g). IR (KBr, cm–1): 3064, 2983, 1725, 1605,
1224, 907, 732; 1H NMR (400 MHz, CDCl3): δ 0.92–0.95 (t, 3H, J
= 7.08 Hz), 2.73 (s, 3H), 4.03–4.07 (q, 2H, J = 7.08 Hz),
7.32–8.00 (m, 8H); 13C NMR (100 MHz, DMSO d6): δ 13.8, 23.7,
61.6, 124.9, 125.7, 129.1, 129.3, 129.4, 129.5, 131.3, 131.4,
131.8, 134.6, 145.1, 145.9, 155.0, 167.5.
2.5. Typical procedure for the preparation of substituted
quinolines
A mixture of 2‐aminobenzophenone (1 mmol), acety‐
lacetone (1.0 mmol), and P(4VPBSA)HSO4 (0.05 g, 10 mol%)
was stirred for 30–60 min under solvent‐free conditions at 110
°C. Upon completion of the reaction by TLC (ethyl ace‐
tate/n‐hexane (2:5, v/v)), the insoluble crude product was dis‐
solved in hot ethanol and the P(4VPBSA)HSO4 was removed by
filtration. The desired product subsequently precipitated from
the filtrate on cooling and was collected by filtration in high
purity. Further purification could be achieved as necessary by
recrystallization of this material from ethanol.
3. Results and discussion
The P(4‐VPBSA)HSO4 catalyst was readily prepared in two
steps via the reaction of P(4VP) with 1,4‐butane sultone fol‐
lowed by acidification of the resulting product with sulfuric
acid (Scheme 3).
FT‐IR spectroscopy was employed to confirm the successful
functionalization of the P(4VP) with 1,4‐butane sultone and its
subsequent acidification with sulfuric acid. The FT‐IR spectrum
of P(4VPBSA)HSO4 is shown in Fig. 1. The spectrum contained
2.6. Selected spectra of some representative compounds
N‐[(3‐nitro phenyl)‐(2‐hydroxy‐naphthalen‐1‐yl)‐methyl]‐
acetamide (Table 2, Entry 3, 4c). IR (KBr, cm–1): 3403, 3141,
3058, 2977, 1641, 1527, 1437, 1348, 1280, 1071, 990, 832,
745; 1H NMR (400 MHz, DMSO‐d6): δ 2.01 (s, 3H), 7.17 (t, J = 8.0
Hz, 1H), 7.19 (d, J = 8.6 Hz, 1H), 7.24 (t, J = 7.4 Hz, 1H), 7.38 (t, J
= 7.4 Hz, 1H), 7.51 (m, 2H), 7.78 (t, J = 8.6 Hz, 2H), 7.83 (br, 1H),
7.97–7.99 (m, 2H), 8.58 (d, J = 8.0 Hz, 1H), 10.16 (s, 1H); 13C
NMR (100 MHz, DMSO‐d6): δ 23.1, 48.2, 118.3, 118.9, 120.9,
121.8, 123.1, 127.3, 123.2, 128.9, 129.2, 130.1, 130.5, 132.7,
133.4, 145.9, 148.2, 153.9, 170.3.
120
115
110
105
100
95
90
N‐[(2‐Chloro phenyl)‐(2‐hydroxy naphthalen‐1‐yl)‐methyl]‐
acetamide (Table 2, Entry 7, 4g). IR (KBr, cm–1): 3418, 3064,
1655, 1580, 1534, 1509, 1470, 1437, 1369, 1334, 1270, 1062,
1036, 815, 752, 569; H NMR (400 MHz, DMSO‐d6): δ 1.91 (s,
3H), 7.56–7.08 (m, 8H), 7.73 (d, J = 7.6 Hz, 1H), 7.78 (d, J = 6.1
85
4000 3500 3000 2500 2000 1500 1000 500
Wavenumber (cm1)
1
Fig. 1. FT‐IR spectrum of P(4VPBSA)HSO4.
O
O
S
O
n
n
H2SO4
n
Toluene
N
N
N
N
N
N
HSO4
HSO4
HO3S
O3S
Scheme 3. Preparation of the P(4‐VPBSA) catalyst.
HO3S
O3S

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
20
0
0.5
P(4VP)
0.0
-20
-40
-60
-80
-100
-0.5
-1.0
-1.5
-2.0
-2.5
0
100 200 300 400 500 600 700 800 900 1000
Temperature (oC)
Fig. 2. TGA curves of P(4VPBSA)HSO4.
P(4VPBSA)HSO4
peaks at 1039, 1113, and 1187 cm–1 corresponding to S=O
stretching vibrations of the –SO3H groups, as well as a broad
peak around 3400 cm–1 corresponding to the OH vibration.
The TGA results (Fig. 2) revealed that the catalyst was com‐
pletely stable below 300 °C and could therefore be applied
without any danger of degradation.
Analysis of the catalyst by SEM allowed for the morphology
of the catalyst particles to be studied. The SEM micrograph of a
sample of the P(4VP) revealed that this material was formed
through the agglomeration of grains with smooth surface. The
SEM micrograph of the acidic catalyst, P(4VPBSA)HSO4,
showed that the primary smoothness had changed, as a conse‐
quence of the chemical modifications, to a coarse surface (Fig
3). It is noteworthy that the dispersion of the catalyst increased
following the functionalization of the P(4VP).
Following the qualification of the catalyst, it was decided to
evaluate the catalytic activity of the catalyst for the preparation
of 1‐amidoalkyl‐2‐naphthols. The reaction of benzaldehyde (1.0
mmol) with β‐naphthol (1.0 mmol) and acetamide (1–1.5
mmol) was selected as a model reaction, and the reaction was
evaluated using different loadings of the P(4VPBSA)HSO4 (i.e.,
5, 10, and 15 mol%) under solvent‐free conditions at 110 °C
(Table 1). The results revealed that a catalyst loading of 10
mol% with 1.2 mmol of acetamide at 110 °C gave the highest
yield with the shortest reaction time. Then use of a higher
loading of the catalyst (15 mol%) did not have a discernible
impact on the yield or the rate of the reaction (Table 1).
Fig. 3. SEM images of P(4VP) and P(4VPBSA)HSO4.
solvent‐free conditions, the generality and synthetic scope of
this coupling protocol were demonstrated through the synthe‐
sis of a series of 1‐amidoalkyl‐2‐naphthols (Table 2). Pleasingly,
a wide range of aromatic aldehydes with electron donating or
electron withdrawing groups was well tolerated under the
optimized reaction conditions. Although the reaction time re‐
mained largely unchanged, we postulated that the electron
withdrawing groups accelerated the reaction on the basis of the
enhanced electrophilicity of the β‐carbon, which facilitates the
subsequent Michael addition. It is also noteworthy that aro‐
matic aldehydes bearing electron withdrawing groups provid‐
ed higher yields of the products. The time taken for complete
conversion (monitored by TLC) as well as the isolated yields
are recorded in Table 2. All of the compounds were character‐
1
ized by IR, and H and 13C NMR, and their spectra were com‐
With the optimal reaction conditions in hand, consisting of a
1:1:1.2 molar ratios of aldehyde, β‐naphthol and acetamide
with a 10 mol% loading of P(4VPBSA)HSO4 at 110 °C under
pared with those of the authentic samples.
We then proceeded to evaluate the catalytic activity of the
Table 1
Optimum conditions for the reaction of β‐naphthol (1 mmol), with benzaldehyde (1 mmol), and acetamide (1–1.5 mmol) with different loadings of
the P(4VPBSA)HSO4 catalyst.
Entry
Acetamide (mmol)
Catalyst (mol%)
T/°C
80
80
100
110
80
110
100
110
Time (min)
Yield (%)
20
1
2
3
4
5
6
7
8
1.0
1.0
1.1
1.2
1.0
1.2
1.2
1.5
—
5
5
120
120
120
80
60
12
45
58
65
72
95
90
89
5
10
10
15
15
15
10

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
Table 2
One‐pot preparation of 1‐amidoalkyl‐2‐naphthols promoted by P(4VPBSA)HSO4 under solvent‐free conditions at 110 °C.
Melting point (°C)
Entry
1
R
Product
Time (min) Yield (%)
Found
Ref.
H C
O
3
H
12
95
242–243
245–246 [16]
NH
OH
4a
O N
H C
O
2
3
2
4‐NO2
10
98
245–246
248–250 [16]
NH
OH
4b
O
H C
3
3
4
3‐NO2
3‐F
10
20
92
90
243–245
249–250
241–242 [16]
248–249 [16]
NH
OH
O N
2
4c
O
H3C
NH
OH
F
4d
H3C
H3C
O
5
6
4‐CH3
15
15
91
89
220–221
184–186
222–223 [16]
183–185 [16]
NH
OH
4e
MeO
H3C
O
4‐OMe
NH
OH
4f
O
H3C
7
2‐Cl
4‐CN
4‐OH
4‐Cl
15
10
15
10
96
97
92
93
210–211
255–257
212–214
224–226
213–215 [16]
260–262 [37]
207 [38]
NH
OH
Cl
4g
NC
H3C
O
8
NH
OH
4h
O
HO
H C
3
9
NH
OH
4i
O
Cl
H3C
10
223–225 [16]
NH
OH
4j
catalyst in the preparation of substituted quinolines. Following
the optimization of the reaction conditions (i.e., 2‐aminoben‐
zophenone (1.0 mmol) and acetylacetone (1.2 mmol) with a 10
mol% loading of P(4VPBSA)HSO4), a series of substituted quin‐
olines were prepared at 110 °C under solvent‐free conditions
(Table 3).
Given the increasing levels of interest in green chemistry,
we decided to evaluate the recyclability and reusability of the
catalyst. Upon completion of the reaction, the separated cata‐
lyst was washed with hot ethanol and dried. The catalyst was
then used for four more cycles. Pleasingly, the catalyst gave a
consistent performance across all four cycles (Fig. 4).

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
Table 3
One‐pot preparation of substituted quinolines via the reaction of an aminoketone (1.0 mmol) with an α‐CH acidic ketone (1.2 mmol) in the presence
of the P(4VPBSA)HSO4 catalyst under solvent‐free conditions at 110 °C.
Melting point (°C)
Time
(min)
45
Yield
(%)
88
Entry
1
Aminoketone
Ketone
Product
Found
Ref.
Ph
Ph
O
114
112–115 [27]
O
O
O
N
NH
2
6a
7a
O
5a
5a
Ph
EtO
2
3
4
50
60
40
90
75
92
95
93 [27]
O
OEt
O
N
7b
Ph
6b
O
5a
5a
142
152
138–141 [27]
151–153 [27]
6c
N
7c
O
O
O
O
Ph
O
6d
N
7d
O
Ph
5
6
7
5a
30
40
45
95
91
92
190
152
110
192 [39]
151 [31]
108 [31]
N
6e
7e
Ph
O
Ph
O
Cl
Cl
O
O
N
NH2
6f
7f
5b
5b
EtO
Ph
O
O
O
Cl
OEt
N
6g
7g
Ph
O
8
9
5b
5b
50
35
78
80
165
186
163 [31]
Cl
Cl
6h
N
7h
Ph
O
O
O
O
O
187–188 [39]
6i
N
7i
Ph
O
10
5b
30
93
210
211 [39]
Cl
N
6j
7j
To demonstrate the superiority of P(4VPBSA)HSO4 over the
other catalysts reported in the literature for the same reaction,
the reaction of benzaldehyde with β‐naphthol and acetamide
was considered as a representative example and conducted in
the presence of a range of different catalysts (Table 4). Alt‐
hough comparative yields of the desired product were obtained
in all cases, with the exception of the P(4VPBSA)HSO4‐catalyzed
and sulfamic acid‐catalyzed procedures, all of the other re‐
ported procedures required long reaction time, or high load‐
ings of the catalyst (Table 4, Entry 5). These results clearly
demonstrate that the P(4VPBSA)HSO4 catalyst is equal to and
in many cases much more efficient for this reaction than the
other catalysts.
The performance of the current catalyst was also compared

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
[4] Davoodnia A, Zare‐Bidaki A, Behmadi H. Chin J Catal, 2012, 33:
Time
Yield
100
80
60
40
20
0
100
80
60
40
20
0
1797
[5] Sayyafi M, Seyyedhamzeh M, Khavasi H R, Bazgir A. Tetrahedron,
2008, 64: 2375
[6] Singh M S, Chowdhury S. RSC Adv, 2012, 2: 4547
[7] Kusakabe Y, Nagatsu J, Shibuya M, Kawaguchi O, Hirose C, Shirato
S. J Antibiot, 1972, 25: 44
[8] Remillard S, Rebhun L I, Howie G A, Kupchan S M. Science, 1975,
189: 1002
[9] Ren H, Grady S, Gamenara D, Heinzen H, Moyna P, Croft S L,
Kendrick H, Yardley V, Moyna G. Bioorg Med Chem Lett, 2001, 11:
1851
[10] Benedini F, Bertolini G, Cereda R, Dona G, Gromo G, Levi S, Mizrahi
J, Sala A. J Med Chem, 1995, 38: 130
1
2
3
Run
4
5
[11] Clark R D, Caroon J M, Kluge A F, Repke D B, Roszkowski A P,
Strosberg A M, Baker S, Bitter S M, Okada M D. J Med Chem, 1983,
26: 657
Fig. 4. Reusability of the catalyst in the reaction of benzaldehyde (1.0
mmol) with β‐naphthol (1.0 mmol) and acetamide (1.2 mmol) at 110 °C
under solvent‐free conditions.
[12] Shen A Y, Tsai C T, Chen C L. Eur J Med Chem, 1999, 34: 877
[13] Ravindran A, Srivastava R. Chin J Catal, 2011, 32: 1597
[14] Kantevari S, Vuppalapati S V N, Nagarapu L. Catal Commun, 2007,
8: 1857
[15] Das B, Laxminarayana K, Ravikanth B, Rao B R. J Mol Catal A, 2007,
261: 180
with a range of other reported catalysts for the preparation of
substituted quinolines, as shown in Table 5. The results of this
comparison study revealed that P(4VPBSA)HSO4 accelerated
the rate of the reaction considerably at the same time as
providing a high yield of the desired product.
[16] Shaterian H R, Yarahmadi H, Ghashang M. Bioorg Med Chem Lett,
2008, 18: 788
4. Conclusions
[17] Nagarapu L, Baseeruddin M, Apuri S, Kantevari S. Catal Commun,
2007, 8: 1729
[18] Patil S B, Singh P R, Surpur M P, Samant S D. Ultrason Sonochem,
2007, 14: 515
[19] Lei M, Ma L, Hu L H. Tetrahedron Lett, 2009, 50: 6393
[20] Marco‐Contelles J, Perez‐Mayoral E, Samadi A, do Carmo Carreiras
M, Soriano E. Chem Rev, 2009, 109: 2652
[21] Friedländer P. Ber Deutsch Chem Ges, 1882, 15: 2572
[22] Fehnel E A. J Org Chem, 1966, 31: 2899
[23] Yadav J S, Rao P P, Sreenu D, Rao R S, Kumar V N, Nagaiah K, Pra‐
sad A R. Tetrahedron Lett, 2005, 46: 7249
[24] Wang G W, Jia C S, Dong Y W. Tetrahedron Lett, 2006, 47: 1059
[25] Narasimhulu M, Srikanth Reddy T, Chinni Mahesh K, Prabhakar P,
Bhujanga Rao C, Venkateswarlu Y. J Mol Catal A, 2007, 266: 114
[26] Dabiri M, Baghbanzadeh M, Nikcheh M S. Monatsh Chem, 2007,
138: 1249
We have developed a facile and environmentally friendly
protocol for the syntheses of 1‐amidoalkyl‐2‐naphthols and
substituted quinolines in the presence of poly(4‐vinylpyridine
butane sulfonic acid) as a novel environmentally safe hetero‐
geneous solid acid catalyst under solvent‐free conditions. This
method offers several advantages over the existing catalytic
systems including high yields, recyclable catalyst, short reac‐
tion time, facile work‐up, and the ability to perform the reac‐
tion under solvent‐free conditions.
References
[1] Mecerreyes D. Prog Polym Sci, 2011, 36: 1629
[2] Yuan J Y, Antonietti M. Polymer, 2011, 52: 1469
[3] Tanaka K, Toda F. Chem Rev, 2000, 100: 1025
[27] Ghassamipour S, Sardarian A R. Tetrahedron Lett, 2009, 50: 514
[28] Barbero M, Bazzi S, Cadamuro S, Dughera S. Tetrahedron Lett,
Table 4
Comparison of P(4VPBSA)HSO4 with other reported catalysts in the reaction of benzaldehyde with β‐naphthol and acetamide.
Entry
Catalyst/Condition
Montmorillonite K10/neat 125 °C
I2/Solvent‐free 125 °C
Fe(HSO4)3/Solvent‐free 85 °C
K5CoW12O40·3H2O/125 °C
Sulfamic acid/Ultrasound r.t.
Thiamine HCl/EtOH reflux
P(4VPBSA)HSO4/Solvent‐free 110 °C
Catalyst loading (mol%)
Time (min)
Yield (%)
89
Ref.
[14]
[15]
[16]
[17]
[18]
[19]
this work
1
2
3
4
5
6
7
0.1 g
5
5
90
330
65
120
15
85
83
90
89
90
95
1
50
10
10
240
12
Table 5
Comparison of P(4VPBSA)HSO4 with several other reported catalysts for the reaction of 2‐aminobenzophenone with acetyl acetone.
Entry
Catalyst/Temperature (°C)
NaAuCl4·2H2O/80
[Hbim]BF4/100
Oxalic acid/80
HClO4‐SiO2/60
P(4VPBSA)HSO4/Solvent‐free/110
Catalyst loading (mol%)
Time
1 d
3.3 h
2 h
2.5 h
45 min
Yield (%)
Ref.
[32]
[31]
[26]
[25]
1
2
3
4
5
3
100
10
0.2 g
10
46
94
90
92
88
this work

Ali Reza Kiasat et al. / Chinese Journal of Catalysis 34 (2013) 1861–1868
Graphical Abstract
Chin. J. Catal., 2013, 34: 1861–1868 doi: 10.1016/S1872‐2067(12)60659‐7
Poly(4‐vinylpyridinium butane sulfonic acid) hydrogen sulfate: An efficient, heterogeneous poly(ionic liquid), solid acid
catalyst for the one‐pot preparation of 1‐amidoalkyl‐2‐naphthols and substituted quinolines under solvent‐free conditions
Ali Reza Kiasat *, Arash Mouradzadegun, Seyyed Jafar Saghanezhad
Shahid Chamran University, Iran
R
O
HO3S
R2
X
CHO
HSO4
SO3H
O
H
H3N
CH3
-
2a j
N
3
O
HSO4
N
HO3
S
NH2
N
R1
R
OH
HSO4
N
5a: X = H, R = Ph
5b: X = Cl, R = Ph
6
1
NH
HSO4
P(4VP)
HSO4
N
N
SO3H
R
HSO4
HO3S
N
HSO4
H3C
O
NH
R2
N
H
R
HSO4
HSO4
NH
HSO4
-
4a j
N
R1
-
OH
7a j
The application of poly(ionic liquids) (PILs) as novel catalysts provides chemists with the advantages of ionic liquids (ILs) as well as those
of heterogeneous catalysts. Poly(4‐vinylpyridinium butane sulfonic acid) hydrogen sulfate has been used as dual acidic PIL for the
one‐pot multi‐component syntheses of 1‐amidoalkyl‐2‐naphthols and substituted quinolones.
2010, 51: 2342
[34] Kiasat A R, Mouradzadegun A, Saghanezhad S J. J Serb Chem Soc,
2013, 78: 469
[35] Kiasat A R, Mouradzadegun A, Saghanezhad S J. J Serb Chem Soc,
2013, doi: 10.2298/JSC121108008K. Ref. No. 5503
[36] Kiasat A R, Mouradzadegun A, Saghanezhad S J. Res Chem In‐
termed, doi: 10.1007/s11164‐013‐1194‐0
[37] Mahdavinia G H, Bigdeli M A, Heravi M M. Chin Chem Lett, 2008,
19: 1171
[38] Kotadia D A, Soni S S. J Mol Catal A, 2012, 353‐354: 44
[39] Ghorbani‐Vaghei R, Akbari‐Dadamahaleh S. Tetrahedron Lett,
2009, 50: 1055
[29] Zolfigol M A, Salehi P, Ghaderi A, Shiri M. Catal Commun, 2007, 8:
1214
[30] Genovese S, Epifano F, Marcotullio M C, Pelucchini C, Curini M.
Tetrahedron Lett, 2011, 52: 3474
[31] Palimkar S S, Siddiqui S A, Daniel T, Lahoti R J, Srinivasan K V. J Org
Chem, 2003, 68: 9371
[32] Atechian S, Nock N, Norcross R D, Ratni H, Thomas A W, Verron J,
Masciadri R. Tetrahedron, 2007, 63: 2811
[33] Das B, Damodar K, Chowdhury N, Kumar R A. J Mol Catal A, 2007,
274: 148