Synthesis of Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes Under Solvent-Free Conditions

Full text of DOI:10.1080/00304948.2019.1653126

Organic Preparations and Procedures International
The New Journal for Organic Synthesis
ISSN: 0030-4948 (Print) 1945-5453 (Online) Journal homepage: https://www.tandfonline.com/loi/uopp20
Synthesis of Quinolines, Spiro[4H-pyran-oxindoles]
and Xanthenes Under Solvent-Free Conditions
Farzaneh Mohamadpour, Malek Taher Maghsoodlou, Mojtaba Lashkari,
Reza Heydari & Nourallah Hazeri
To cite this article: Farzaneh Mohamadpour, Malek Taher Maghsoodlou, Mojtaba Lashkari,
Reza Heydari & Nourallah Hazeri (2019): Synthesis of Quinolines, Spiro[4H-pyran-oxindoles] and
Xanthenes Under Solvent-Free Conditions, Organic Preparations and Procedures International,
DOI: 10.1080/00304948.2019.1653126
To link to this article: https://doi.org/10.1080/00304948.2019.1653126
Published online: 19 Aug 2019.
Submit your article to this journal
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at
https://www.tandfonline.com/action/journalInformation?journalCode=uopp20

Organic Preparations and Procedures International, 0:1–21, 2019
# 2019 Taylor & Francis Group, LLC
ISSN: 0030-4948 print / 1945-5453 online
DOI: 10.1080/00304948.2019.1653126
Synthesis of Quinolines, Spiro[4H-pyran-oxindoles]
and Xanthenes Under Solvent-Free Conditions
Farzaneh Mohamadpour,1 Malek Taher Maghsoodlou,1 Mojtaba
Lashkari,2 Reza Heydari,1 and Nourallah Hazeri1
1Department of Chemistry, Faculty of Science, University of Sistan and
Baluchestan, P. O. Box 98135-674, Zahedan, Iran
2Faculty of Science, Velayat University, Iranshahr, Iran
Green multi-component domino reactions (MCRs)1–7 for the synthesis of fine chemicals
have attracted much recent interest.8–9 Quinolines, spiro[4H-pyran-oxindoles] and xanthenes
are reported as having a wide range of medicinal properties.10–17 Quinolines are found to
undergo hierarchical self assembly into a variety of nano-structures and meso structures
with enhanced electronic and photonic functions.18 Xanthenes have been widely used as
pH sensitive fluorescent materials for visualization of biomolecules,19 laser technology,20
luminescent dyes21 and sensitizers in photodynamic therapy.22 (Figure 1).
A number of methodologies for preparation of these compounds have been reported
that include such catalysts as Fe3O4@SiO2-imid-PMAn,23 SBNPTT,24 NO2ꢀFePc/C,25
nano-alumina sulfuric acid26 and many others.27–55 However, some of these methods suffer
from such disadvantages as low yields, long reaction times, harsh reaction conditions, tedi-
ous work-up or excess amounts of reagents or catalysts. As part of our ongoing research
program on the development of green methodologies, we now report a clean and facile
one-pot synthesis of polysubstituted quinolines,56 spiro[4H-pyran] derivatives, 12-aryl-tetra-
hydrobenzo[a]xanthene-11-ones and 14-aryl-14H-dibenzo[a,j]xanthenes, in the presence of
catalytic amounts of citric acid under solvent-free conditions.
Initial screening studies confirmed that the solvent-free technique is optimal for the
preparation of quinolines 3a-g (Scheme 1, Table 1). Thus, the cyclocondensation of 2-
aminobenzophenone (1.0 mmol) and dimedone (1.0 mmol) was carried out with citric
acid (15 mol %) as catalyst at 90 ꢁC for 15 min under solvent-free conditions to give a
yield of 92% (Table 1, Entry 4). The efficiency of citric acid was demonstrated by syn-
thesizing a variety of polysubstituted quinolines at 90 ꢁC under solvent-free conditions,
as shown in Table 2.
We explored citric acid as an environmentally friendly catalyst for the synthesis of
spiro[4H-pyran-oxindoles] through the coupling of isatin/acenaphthequinone (4,
1.0 mmol), malononitrile (5, 1.0 mmol) and 1,3-dicarbonyl compounds (6, 1.0 mmol).
Isatin, malononitrile and dimedone were selected as the model substrates and reacted
with different experimental variants (Scheme 2). The results are summarized in Table 3.
Received September 4, 2018; in final form March 18, 2019.
Address correspondence to Malek Taher Maghsoodlou, Department of Chemistry, Faculty of
Science, University of Sistan and Baluchestan, P.O. Box 98135-674, Zahedan, Iran. E-mail:
mt_maghsoodlou@yahoo.com; mt_maghsoodlou@chem.usb.ac.ir
1

2
Maghsoodlou et al.
Figure 1. Pharmaceutically active compounds with quinoline, spirocyclic oxindole and xan-
thene units.
Scheme 1. Synthesis of polysubstituted quinolines.
The condensation of isatin, malononitrile and dimedone was best catalyzed by 20 mol
% citric acid at 80 ꢁC (Table 3, entry 5). In the absence of catalyst only a trace of prod-
uct was observed (Table 3, entry 1). To ascertain the scope and limitation of the present
protocol, a number of reactions were examined, and the results are summarized in
Table 4. We were pleased to find that all substrates were converted to the corresponding
products in good to excellent yields (82-93%).

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
3
Table 1
Optimization of the Reaction Conditions for the Synthesis of 3aa
Citric acid
(mol %)
Time
(min)
Isolated
Yields (%)
Entry
Temperature (ꢁC)
1
2
3
4
5
6
7
8
Catalyst free
90
90
90
90
rt
40
60
80
100
90
420
40
No product
5
58
74
92
trace
36
67
83
92
94
10
15
15
15
15
15
15
20
25
15
420
55
35
25
15
9
10
15
aReaction conditions: 2-aminobenzophenone (1, 1.0 mmol), carbonyl compound (2, 1.0 mmol)
and citric acid heated at specified various temperatures for the times listed.
We were further interested in the preparation of 12-aryl-tetrahydroben-
zo[a]xanthene-11-ones and the influence of a catalytic amount of citric acid on this
type of reaction (Scheme 3). To obtain the optimized reaction conditions, the condensa-
tion of b-naphthol (1.0 mmol), benzaldehyde (1.0 mmol) and dimedone (1.0 mmol) was
selected as a model. This reaction gave the desired 12-(phenyl)-9,9-dimethyl-8,9,10,12-
tetrahydrobenzo[a]xanthene-11-one and was studied in the presence of different molar
ratios of citric acid at rt-90 ꢁC under solvent-free conditions; the respective results are
summarized in Table 5. The best results were obtained when the reaction was carried
out using 20 mol % of the catalyst at 80 ꢁC (Table 5, entry 5). To assess the efficiency
and generality of the catalyst, b-naphthol (8, 1.0 mmol) was reacted with aromatic alde-
hyde derivatives (9, 1.0 mmol) and dimedone (10, 1.0 mmol). The results are displayed
in Table 6. As Table 6 indicates, aldehydes with both electron-donating substituents
and electron-attracting substituents rings afforded the desired products in high yields
and short reaction times.
We were also interested in the preparation of 14-aryl-14H- dibenzo[a,j]xanthenes
from the reaction between b-naphthol (8, 2.0 mmol) and aromatic aldehyde derivatives
(9, 1.0 mmol) in the present of citric acid under thermal and solvent-free conditions
(Scheme 4). For optimization of the reaction conditions, the reaction of b-naphthol
(2.0 mmol) and benzaldehyde (1.0 mmol) was chosen as the model, carried out in the
presence of different catalytic amounts of citric acid and at various temperatures. The
best result was obtained for the reaction of 2.0 mmol of b-naphthol with 1.0 mmol of
benzaldehyde in the presence of 20 mol % citric acid at 80 ꢁC, which gave 14-phenyl-
14H-dibenzo[a,j]xanthene in 95% yield after 10 min (Table 7, entry 5). The model reac-
tion was performed in the absence of catalyst, which led to only a trace of product after

4
Maghsoodlou et al.
Table 2
Citric Acid Catalyzed Synthesis of Polysubstituted Quinolines
Isolated
Time Yields
(min) (%)
Lit.
ref
Entry Ketone/Ketoester
1
Product
MpꢁC MpꢁC
15
92
191-193 192-19427
2
3
4
5
10
15
15
15
93
89
87
91
155-157 157-15923
154-156 153-15427
128-130 129-13127
99-101 98-9923
6
7
15
10
94
92
105-107 107-10823
114-116 113-11423
7 hours. Different aldehydes and b-naphthol were reacted under the optimized reaction
conditions to afford the corresponding products (Scheme 4, Table 8, entries 1-13). As
shown in Table 8, both electron-donating and electron-withdrawing substituents in the
benzaldehydes satisfactorily reacted with b-naphthol in good to excellent yields.
Comparisons of catalytic abilities reported in the literature for the synthesis of poly-
substituted quinolines, spiro[4H-pyran-oxindoles], 12-aryl-tetrahydrobenzo[a]xanthene-11-
ones and 14-aryl-14H-dibenzo[a,j]xanthenes are shown in Tables 9, 10, 11 and 12.

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
5
Scheme 2. Synthesis of spiro[4H-pyran-oxindoles].
Table 3
Optimization of the Reaction Conditions for the Synthesis of 7aa
Citric acid
(mol %)
Temperature
(ꢁC)
Time
(min)
Isolated
Yields (%)
Entry
1
2
3
4
5
6
7
8
Catalyst free
80
80
80
80
80
rt
40
60
70
90
80
420
75
65
50
40
420
70
55
45
10
40
trace
63
76
94
91
trace
35
57
76
93
5
10
15
20
20
20
20
20
20
25
9
10
11
92
aReaction conditions: isatin (4, 1.0mmol); malononitrile (5, 1.0 mmol), dimedone (6, 1.0 mmol)
and citric acid heated at specified temperatures for the appropriate times.
In summary, a green synthetic route to the facile preparation of polysubstituted qui-
nolines, spiro[4H-pyran-oxindoles], 12-aryl-tetrahydrobenzo[a]xanthene-11-ones and
14-aryl-14H-dibenzo[a,j]xanthenes has been developed using citric acid as a catalyst
under solvent-free reaction conditions. All reactions are completed in a short period of
time and the products are obtained in good to excellent yields. The salient features of
this green approach are easy work-up, the absence of organic solvents and the use of a
readily available green catalyst.

6
Maghsoodlou et al.

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
7

8
Maghsoodlou et al.

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
9

10
Maghsoodlou et al.
Scheme 3. Synthesis of 12-aryl-tetrahydrobenzo[a]xanthene-11-ones.
Table 5
Optimization of the Reaction Conditions for the Synthesis of 11aa
Citric acid
(mol %)
Time
(min)
Isolated
Yields (%)
Entry
Temperature (ꢁC)
1
2
3
4
5
6
7
8
Catalyst free
80
80
80
80
80
rt
40
60
70
90
80
420
45
35
20
10
420
55
45
20
10
10
trace
49
65
81
93
trace
37
59
74
93
5
10
15
20
20
20
20
20
20
25
9
10
11
92
aReaction conditions: b-naphthol (8, 1.0 mmol), benzaldehyde (9, 1.0 mmol), dimedone (10,
1.0 mmol) and citric acid heated at specified temperatures for the appropriate times.
Experimental Section
Melting points of all compounds were determined using an Electro thermal 9100 appar-
1
atus and are uncorrected H NMR spectra were recorded on a Bruker DRX-400 Avance
instrument with CDCl3 or DMSO-d6 as solvents. All reagents and solvents were

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
11
Table 6
Citric Acid Catalyzed Synthesis of 12-aryl-tetrahydrobenzo[a]xanthene-11-ones
Time Yields
(min) (%)
Lit.
ref
Entry Aldehyde
Product
MpꢁC MpꢁC
1
10
25
93 148-150 148-15043
2
84 182-184 184-18643
3
4
25
15
85 163-165 161-16444
94 177-179 175-17844
5
6
15
20
95 165-167 167-16945
87 204-206 202-20443
(Continued)

12
Maghsoodlou et al.
Table 6
(Continued).
Time Yields
(min) (%)
Lit.
ref
Entry Aldehyde
Product
MpꢁC MpꢁC
7
20
25
90 205-207 204-20546
8
86 175-177 176-17843
9
25
10
87 180-182 179-18047
10
96 182-184 184-18545
11
10
94 172-174 171-17343
purchased from Merck, Fluka and Acros chemical companies and were used without
further purification. TLC was done on silica gel plates, using solvents specified in indi-
vidual procedures.

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
13
Scheme 4. Synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes.
Table 7
Optimization of the Reaction Conditions for the Synthesis of 12aa
Citric acid
(mol %)
Time
(min)
Isolated
Yields (%)
Entry
Temperature (ꢁC)
1
2
3
4
5
6
7
8
Catalyst free
80
80
80
80
80
rt
40
60
70
90
80
420
50
35
15
10
420
55
30
20
10
10
trace
47
68
83
95
trace
51
67
79
94
5
10
15
20
20
20
20
20
20
25
9
10
11
95
aReaction conditions: b-naphthol (8, 2.0 mmol), benzaldehyde (9, 1.0 mmol) and citric acid
heated at specified temperatures for the appropriate times.
General Procedures for Preparation of Polysubstituted Quinolines, Spiro[4H-
pyran-oxindoles], 12-aryl-tetrahydrobenzo[a]xanthene-11-ones and 14-aryl-14H-
dibenzo[a,j]xanthenes
Synthesis of polysubstituted quinolines (3): A mixture of 2-aminobenzophenone (1,
1.0 mmol), ketone/ketoester (2, 1.0 mmol) and citric acid (15 mol %) was heated at 90ꢁC
for the appropriate time. After completion of the reaction (TLC using ethylacetate/n-hexane

14
Maghsoodlou et al.
Table 8
Citric Acid Catalyzed Synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes
Time Yields
(min) (%)
Lit.
ref
Entry Aldehyde
Product
MpꢁC
MpꢁC
1
10
20
95
87
182-184 183-18451
2
295-297 297-29843
3
4
20
10
88
91
190-192 191-19345
306-308 308-30952
5
6
10
10
93
93
213-215 212-21352
211-213 213-21452
(Continued)

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
15
Table 8
(Continued).
Time Yields
(min) (%)
Lit.
ref
Entry Aldehyde
Product
MpꢁC
MpꢁC
7
15
89
204-206 204-20543
8
9
10
20
90
86
171-173 172-17352
290-292 289-29051
10
11
20
10
89
94
213-215 212-21351
241-243 240-24253
12k
12
10
92
226-228 227-22843
(Continued)

16
Maghsoodlou et al.
Table 8
(Continued).
Time Yields
(min) (%)
Lit.
ref
Entry Aldehyde
Product
MpꢁC
MpꢁC
13
10
94
195-197 197-19852
Table 9
Comparison of Catalytic Ability of Catalysts Reported in the Literature for Synthesis
of Polysubstituted Quinolinesa
Entry
Catalyst
DSIMHS
FeCl2ꢂ2H2O-RiHA
Conditions
Time/Yield (%) References
1
2
3
4
5
6
7
Solvent-free, 70 ꢁC
25 min/89
35 min/86
35 min/70
45 min/75
210 min/72
35 min/94
15 min/92
[27]
[28]
[29]
[29]
[30]
Solvent-free,90 ꢁC
Cellulose sulfuric acid Solvent-free, 100 ꢁC
Starch sulfuric acid
Amberlyst-15
P2O5/SiO2
Solvent-free, 100 ꢁC
EtOH, Reflux
Solvent-free, 80 ꢁC
Solvent-free, 90 ꢁC
[31]
Citric acid
This work
aBased on reaction of 2-aminobenzophenone (1.0 mmol) and dimedone (1.0 mmol).
Table 10
Comparison of Catalytic Ability of Catalysts Reported in the Literature for Synthesis
of Spiro[4H-pyran-oxindoles]a
Entry
Catalyst
SBNPTT
Silica-Sulfuric acid NPs EtOH, Reflux
Carbon-SO3H
L-Proline
Mg(ClO4)2
Sodium stearate
MgO nanocrystalline
InCl3
Conditions
Time/Yield (%)
References
1
2
3
4
5
6
7
8
9
H2O, Reflux
H2O, Reflux
EtOH, Reflux
EtOH, Reflux
H2O, 80 ꢁC
[24]
[33]
[37]
[38]
[39]
[40]
[41]
[42]
EtOH, Reflux
H2O, 80 ꢁC
EtOH/H2O,50 ꢁC
H2O, 60 ꢁC
EtOH/H2O,50 ꢁC
H2O, 60 ꢁC
H2O, 80 ꢁC
H2O, 80 ꢁC
CH3CN, Reflux
CH3CN, Reflux
Citric acid
Solvent-free, 80 ꢁC Solvent-free, 80 ꢁC This work
aBased on three-component reaction of isatin (1.0mmol), malononitrile (1.0mmol) and dime-
done (1.0mmol)
(3:6) as eluent), 3 ml EtOH was added. The mixture was poured into cold water (10 mL)
and the resulting precipitate was recrystallized from ethanol to give pure product (3a-g).

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
17
Table 11
Comparison of Catalytic Ability of Catalysts Reported in the Literature for Synthesis
of 12-aryl-tetrahydrobenzo[a]xanthene-11-onesa
Entry
Catalyst
Conditions
EtOH, Reflux
Solvent-free, 55 ꢁC
Time/Yield (%) References
1
2
3
4
5
6
7
NO2 ꢀ FePc/C
30 min/91%
20 min/93
30 min/95
300 min/91
120 min/85
300 min/85
10 min/93
[25]
[43]
[45]
[48]
[49]
DSIMHS
Fe3O4@SiO2-SO3H Solvent-free, 110 ꢁC
NaHSO4/SiO2
CAN
Sr(OTf)2
Citric acid
CH2Cl2, Reflux
Microwave irradiation, 120 ꢁC
1,2-Dichloroethane, 80 ꢁC
Solvent-free, 80 ꢁC
[50]
This work
aBased on the three-component reaction of b-naphthol (1.0 mmol), benzaldehyde (1.0 mmol) and
dimedone (1.0 mmol).
Table 12
Comparison of Catalytic Ability of Catalysts Reported in the Literature for Synthesis
of 14-aryl-14H-dibenzo[a,j]xanthenesa
Entry
Catalyst
Conditions
Mg(BF4)2, 80 ꢁC
Time/Yield (%)
References
1
2
3
4
5
6
7
8
[BMim][BF4]
DSIMHS
Fe3O4@SiO2-SO3H
Diatomite-SO3H
[H-NMP][HSO4]
SFP
15 min/95
3 min/94
[35]
[43]
[45]
[51]
[52]
Solvent-free, 90 ꢁC
Solvent-free, 110 ꢁC
Solvent-free, 90 ꢁC
Solvent-free, 110 ꢁC
Solvent-free, 90 ꢁC
Solvent-free, 125 ꢁC
Solvent-free, 80 ꢁC
30 min/94
10 min/93
12 min/94
30 min/98
20 min/98
10 min/95
[54]
[55]
SiO2-Pr-SO3H
Citric acid
This work
aBased on the three-component reaction of b-naphthol (2.0 mmol) and benzaldehyde (1.0 mmol).
Synthesis of spiro[4H-pyran-oxindoles] (7): A mixture of isatin/acenaphthequinone (4,
1.0 mmol), malononitrile (5, 1.0 mmol), and different 1,3-dicarbonyl compounds (6,
1.0 mmol) in the present of citric acid (20 mol %) was heated at 80 ꢁC for the appropri-
ate time. After completion of the reaction (TLC using ethylacetate/n-hexane (3:7) as
eluent), the mixture was cooled to 25 ꢁC, the solid products were filtered and then were
recrystallized from ethanol to give the pure compounds (7a-l).
Synthesis of 12-aryl-tetrahydrobenzo[a]xanthene-11-ones (11): A mixture of b-naphthol
(8, 1.0 mmol), benzaldehyde (9, 1.0 mmol), dimedone (10, 1.0 mmol) and citric acid
(20 mol %) was heated at 80 ꢁC for the appropriate time. After completion of the reac-
tion (TLC using ethylacetate/n-hexane (3:5) as eluent), the mixture was cooled to
25 ꢁC, ethanol was added and the precipitate was separated by filtration. The solid was
recrystallized from ethanol to afford the pure products (11a- k).
Synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes (12): A mixture of b-naphthol (8,
2.0 mmol), benzaldehyde (9, 1.0 mmol) and citric acid (20 mol %) was heated at 80 ꢁC
for the appropriate time. After completion of the reaction (TLC using ethylacetate/n-
hexane (3:5) as eluent), the mixture was cooled to 25 ꢁC and ethanol was added. The

18
Maghsoodlou et al.
Table 13
Spectral Data of Representative Compounds
Compound
Spectral data
1H NMR (400 MHz, CDCl3): 1.19 (6H, s, 2CH3),
2.59 (2H, s, CH2), 3.33 (2H, s, CH2),7.19-7.22
(2H, m, ArH), 7.45 (1H, t, J ¼ 8.0 Hz, ArH), 7.50-
7.56 (4H, m, ArH), 7.80 (1H, t, J ¼ 8.0 Hz, ArH) ,
8.13 (1H, brs, ArH).
1H NMR (400 MHz, DMSO-d6): 1.00 (3H, s, CH3),
1.03 (3H, s, CH3), 2.08-2.19 (2H, m, CH2), 2.53
(2H, s, CH2), 6.79 (1H, d, J ¼ 7.2 Hz, ArH), 6.89
(1H, t, J ¼ 7.2 Hz, ArH), 6.98 (1H, d, J ¼ 6.8 Hz,
ArH), 7.14 (1H, t, J ¼ 6.4 Hz, ArH), 7.22 (2H, s,
NH2), 10.39 (1H, s, NH)
1H NMR (400 MHz, DMSO-d6): 1.02 (3H, s, CH3),
1.04 (3H, s, CH3), 2.04-2.13 (2H, m, CH2), 2.63
(2H, s, CH2), 7.32 (2H, s, NH2), 7.38-8.28 (6H,
m, ArH).
1HNMR (400 MHz, CDCl3): 0.99 (3H, s, CH3), 1.12
(3H, s, CH3), 2.16-2.35 (2H, m, CH2), 2.58 (2H, s,
CH2), 3.71 (3H, s,OCH3), 5.68 (1H, s, CHAr), 6.72
(2H, d, J ¼ 8.4 Hz, ArH), 7.21-7.47 (5H, m, ArH),
7.85 (2H, t, J ¼ 9.2 Hz, ArH), 8.01 (1H, d,
J ¼ 8.4 Hz, ArH).
1H NMR (400 MHz, CDCl3): 1.01 (3H, s, CH3), 1.15
(3H, s, CH3), 2.23 (3H, s, CH3), 2.28 (1H, d,
J ¼ 16.0 Hz, CH2), 2.34 (1H, d, J ¼ 16.0 Hz, CH2),
2.60 (2H, s, CH2), 5.71 (1H, s, CHAr), 7.00–8.06
(10H, m, ArH).
1H NMR (400 MHz, CDCl3): 2.18 (3H, s, CH3), 6.47
(1H, s, CHAr), 6.81(1H, d, J ¼ 7.6 Hz, ArH),
6.81(1H, t, J ¼ 7.6 Hz, ArH), 7.40-7.85 (12H, m,
ArH), 8.42 (2H, d, J ¼ 8.8 Hz, ArH).

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
19
precipitate was separated by filtration and the solid was recrystallized from ethanol to
afford the pure products (12a-m). The products have been characterized by melting
1
points and H NMR spectroscopy. Spectral data of selected products are reported in
Table 13.
Acknowledgments
We gratefully acknowledge financial support from the Research Council of the
University of Sistan and Baluchestan.
References
1. Y. Wang, X. Liu and C. Du, Org. Prep. Proc. Int., 49, 28 (2017).
2. S. F. Hojati and H. Raouf, Org. Prep. Proc. Int., 48, 474 (2016).
3. S. Ameli, A. Davoodnia and M. Pordel, Org. Prep. Proc. Int., 48, 328 (2016).
4. B. Maleki, E. Sheikh, E. Rezaei Seresht, H. Eshghi, S. S. Ashrafi, A. Khojastehnezhad and
H. Veisi, Org. Prep. Proc. Int., 48, 37 (2016).
5. K. Karthikeyan and G. Sivaprasad, Org. Prep. Proc. Int., 47, 449 (2015).
€
€
€
6. M. B. Gurdere, S. M. Ozturk and M. Ceylan, Org. Prep. Proc. Int., 47, 473 (2015).
7. F. Mohamadpour, M. T. Maghsoodlou, R. Heydari and M. Lashkari, Res. Chem. Intermed.,
42,7841 (2016).
8. B. Maleki, Org. Prep. Proc. Int., 48, 303 (2016).
9. F. Mohamadpour, M. T. Maghsoodlou, R. Heydari and M. Lashkari, J. Iran. Chem. Soc., 13,
1549 (2016).
10. R. Kakadiya, H. Dong, A. Kumar, D. Narsinh, X. Zhang, T. C. Chou, T. C. Lee, A. Shah
and T. L. Su, Bioorg. Med. Chem., 18, 2285 (2010).
11. H. Vander Mierde, P. van der Voort and F. Verpoort, Tetrahedron Lett., 49, 6893 (2008).
12. N. Muruganantham, R. Sivakumar, N. Anbalagan, V. Gunasekaran and J. T. Leonard, Biol.
Pharm. Bull., 27, 1683 (2004).
13. Y. L. Chen, K. C. Fang, J. Y. Sheu, S. L. Hsu and C. C. Tzeng, J. Med. Chem., 44, 2374
(2001).
€
14. V. V. Vintonyak, K. Warburg, H. Kruse, S. Grimme, K. Hubel, D. Rauh and H. Waldmann,
Angew. Chem. Int. Ed. Engl., 49, 5902 (2010).
15. S. Yu, D. Qin, S. Shangary, J. Chen, G. Wang, K. Ding, D. McEachern, S. Qiu, Z.
Nikolovska-Coleska, R. Miller, S. Kang, D. Yang and S. Wang, J. Med. Chem., 52, 7970
(2009).
16. A. Fensome, W. R. Adams, A. L. Adams, T. J. Berrodin, J. Cohen, C. Huselton, A.
Illenberger, J. C. Kern, V. A. Hudak, M. A. Marella, E. G. Melenski, C. C. McComas, C. A.
Mugford, O. D. Slayden, M. Yudt, Z. Zhang, P. Zhang, Y. Zhu, R. C. Winneker and J. E.
Wrobel, J. Med. Chem. Soc., 51, 1861 (2008).
17. F. Zelefack, D. Guilet, N. Fabre, C. Bayet, S. Chevalley, S. Ngouela, B. N. Lenta, A.
Valentin, E. Tsamo and M. G. Dijoux-Franca, J. Nat. Prod., 72, 954 (2009).

20
Maghsoodlou et al.
18. X. Zhang, A. S. Shetty and S. A. Jenekhe, Macromolecules, 33, 2069 (2000).
19. J. F. Callan, P. De Silva and D. C. Magri, Tetrahedron, 61, 8551(2005).
20. M. Ahmad, T. A. King, D. K. Ko, B. H. Cha and J. Lee, J. Phys. D: Appl. Phys., 35, 1473
(2002).
21. G. R. Fleming, A. W. E. Knight, J. M. Morris, R. J. S. Morrison and G. W. Robinson, J.
Am. Chem. Soc., 99, 4306 (1977).
22. O. Sirkecioglu, N. Talinli and A. Akar, J. Chem. Res. Synop., 12, 502 (1995).
23. M. Esmaeilpour and J. Javidi, J. Chin. Chem. Soc., 62, 328 (2015).
24. K. Niknam and P. Abolpour, Monatsh Chem., 146, 683 (2015).
25. H. Huang, Y. Yao, Q. Lin, J. Zhao, C. Hu and X. Gou, Russ. J. Gen. Chem., 86, 934 (2016).
26. F. Davod, A. R. Kiasat, M. Enjilzadeh and M. Cheraghchi. Lett. Org. Chem., 13, 58 (2016).
27. F. Shirini, A. Yahyazadeh, K. Mohammadi and N. Ghaffari Khaligh, C. R. Chimie, 17, 370
(2014).
28. F. Shirini, S. Akbari-Dadamahaleh and A. Mohammad-Khah, Chin. J. Catal., 34, 2200
(2013).
29. A. Shaabani, A. Rahmati and Z. Badri, Catal. Commun., 9, 13 (2008).
30. B. Das, K. Damodar, N. Chowdhury and R. Aravind Kumar, J. Mol. Catal. A: Chem., 274,
148 (2007).
31. A.R. Hasaninejad, A. Zare, M. A. Zolfigol, M. Abdeshah, A. Ghaderi and F. Nami-Ana,
Iran. J. Chem. Chem. Eng., 30, 73 (2011).
32. L. M. Wang, N. Jiao, J. Qiu, J. J. Yu, J. Q. Liu, F. L. Guo and Y. Liu, Tetrahedron, 66, 339
(2010).
33. B. Sadeghi, M. Ghasemi Pirbaluti, P. Farokhi Nezhad and R. Abbasi Nezhad, Res. Chem.
Intermed., 41, 4047 (2015).
34. G.-D. Wang, X.-N. Zhang and Z.-Hui Zhang, J. Heterocyclic. Chem., 50, 61 (2013).
35. K. Rad-Moghadam and S.C. Azimi, J. Mol.Catal A: Chem., 363-364, 465 (2012).
36. M. Saeedi, M. M. Heravi, Y. S. Beheshtiha and A. Oskooie, Tetrahedron, 66, 5345 (2010).
37. B. Maheshwar Rao, G. Niranjan Reddy, T. Vijaikumar Reddy, B. L. A. Prabhavathi Devi,
R. B. N. Prasad, J. S. Yadav and B. V. Subba Reddy, Tetrahedron Lett., 54, 2466 (2013).
38. Y. Li, H. Chen, C. Shi, D. Shi and S. Ji, J. Comb. Chem., 12, 231 (2010).
39. C. Wu, R. Shen, J. Chen and C. Hu, Bull. Korean. Chem. Soc., 34, 2431 (2013).
40. L. M. Wang, N. Jiao, J. Qiu, J. J. Yu, J. Q. Liu, F. L. Guo and Y. Liu, Tetrahedron, 66, 339
(2010).
41. B. Karmakar, A. Nayak and J. Banerji, Tetrahedron Lett., 53, 5004 (2012).
42. G. Shanthi, G. Subbulakshmi and P. T. Perumal, Tetrahedron, 63, 2057 (2007).
43. F. Shirini, A. Yahyazadeh and K. Mohammadi, Chin. Chem. Lett., 25, 341 (2014).
44. A. Khazaei, M. A. Zolfigol, A. R. Moosavi-Zare, M. Khojasteh, Z. Asgari, V. Khakyzadeh
and A. Khalafi-Nezhad, Catal. Commun., 20, 54 (2012).

Quinolines, Spiro[4H-pyran-oxindoles] and Xanthenes
21
45. F. Nemati and S. Sabaqian, J. Saudi. Chem. Soc., 21, S383 (2017).
46. M. M. Heravi, H. Alinegjhad, K. Bakhtiari and H. Oskooie, Mol. Divers., 14, 621 (2010).
47. F. Nemati, M. Arghan and A. Amoozadeh, Synth. Commun., 42, 33 (2012).
48. B. Das, K. Laxminarayana, M. Krishnaiah and Y. Srinivas, Synlett., 20, 3107 (2007).
49. S. Sudha and M. A. Pasha, Ultra. Sonochem., 19, 994 (2012).
50. J. Li, W. Tang, L. Lu and W. Su, Tetrahedron Lett., 49, 7117 (2008).
51. H. Naeimi and Z. S. Nazifi, App. Catal. A: Gen., 477, 132 (2014).
52. H. Naeimi and Z.S. Nazifi, C.R. Chimie., 17, 41 (2014).
53. G. B. Dharma Rao, M. P. Kaushik and A. K. Halve, Tetrahedron Lett., 53, 2741 (2012).
54. A. B. Zare and F. Reghbat, Iran. J. Catal., 6, 113 (2016).
55. G. Mohammadi Ziarani, A. R. Badiei and M. Azizi, Scientica Iranica., 18, 453 (2011).
€
56. P. Friedlander, Chemische Berichte., 15, 2572 (1882).