Sulfonic acid supported phosphonium based ionic liquid functionalized SBA-15 for the synthesis of 2-amino-3-cyano-4,6-diarylpyridines

Article abstract of DOI:10.1080/15533174.2014.988234

The surface of SBA-15 was functionalized using diphenylphosphine and then it was treated with butane sultone and sulfuric acid to obtain Bronsted acid HO₃S-phosphonium based ionic liquid functionalized SBA-15 with 4-methylbenzenesulfonate (p-TS

Full text of DOI:10.1080/15533174.2014.988234

This article was downloaded by: [ECU Libraries]
On: 25 April 2015, At: 15:18
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,
37-41 Mortimer Street, London W1T 3JH, UK
Synthesis and Reactivity in Inorganic, Metal-Organic,
and Nano-Metal Chemistry
Publication details, including instructions for authors and subscription information:
http://www.tandfonline.com/loi/lsrt20
Sulfonic Acid Supported Phosphonium Based Ionic
Liquid Functionalized SBA-15 for the Synthesis of 2-
Amino-3-cyano-4,6-diarylpyridines
Leila Ma'mania, Elham Hajihosseinia, Mina Saeedib, Mohammad Mahdavia, Ali Asadipourc,
Loghman Firoozpourd, Abbas Shafieea & Alireza Foroumadicd
a Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences
Research Center, Tehran University of Medical Sciences, Tehran, Iran
b Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences,
Tehran, Iran
c Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of
Click for updates
Medical Sciences, Kerman, Iran
d Drug Design and Development Research Center, Tehran University of Medical Sciences,
Tehran, Iran
Accepted author version posted online: 01 Apr 2015.
To cite this article: Leila Ma'mani, Elham Hajihosseini, Mina Saeedi, Mohammad Mahdavi, Ali Asadipour, Loghman Firoozpour,
Abbas Shafiee & Alireza Foroumadi (2015): Sulfonic Acid Supported Phosphonium Based Ionic Liquid Functionalized SBA-15 for
the Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines, Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal
Chemistry, DOI: 10.1080/15533174.2014.988234
To link to this article: http://dx.doi.org/10.1080/15533174.2014.988234
Disclaimer: This is a version of an unedited manuscript that has been accepted for publication. As a service
to authors and researchers we are providing this version of the accepted manuscript (AM). Copyediting,
typesetting, and review of the resulting proof will be undertaken on this manuscript before final publication of
the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the
content, and all legal disclaimers that apply to the journal relate to this version also.
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained
in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no
representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the
Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and
are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and
should be independently verified with primary sources of information. Taylor and Francis shall not be liable for
any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever
or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of
the Content.
This article may be used for research, teaching, and private study purposes. Any substantial or systematic
reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any

form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://
www.tandfonline.com/page/terms-and-conditions

ACCEPTED MANUSCRIPT
Sulfonic Acid Supported Phosphonium Based Ionic Liquid Functionalized SBA-15 for the
Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines
Leila Ma’mani,1 Elham Hajihosseini,1 Mina Saeedi,2 Mohammad Mahdavi,1 Ali
Asadipour,3 Loghman Firoozpour,4 Abbas Shafiee,1 and Alireza Foroumadi 3,4,∗
1Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences
Research Center, Tehran University of Medical Sciences, Tehran, Iran
2Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences,
Tehran, Iran
3Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical
Sciences, Kerman, Iran
4Drug Design and Development Research Center, Tehran University of Medical Sciences,
Tehran, Iran
The surface of SBA-15 was functionalized using diphenylphosphine and then it was
treated with butane sultone and sulfuric acid to obtain Brønsted acid HO3S-phosphonium
based ionic liquid functionalized SBA-15 with 4-methylbenzenesulfonate (p-TS-) as a
counteranion. [HO3S-PhospIL@SBA-15], efficiently catalyzed synthesis of 2-amino-3-
cyano-4,6-diarylpyridine derivatives through the reaction of chalcones, malononitrile, and
ammonium acetate in good yields at 50 °C in EtOH.
∗ Corresponding author. e-mail: aforoumadi@yahoo.com
1
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Keywords
2-amino-3-cyano-4,6-diarylpyridine,
chalcones,
functionalized
SBA-15,
malononitrile, supported ionic liquid
2
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
INTRODUCTION
Pyridine and its derivatives are one the most the important N-heterocycles and have
considered as versatile precursors for the preparation of agrochemicals and pharmaceuticals.[1]
Among them, 2-amino-3-cyano-4,6-diarylpyridine derivatives have aroused significant interest
over the past decades due to a wide variety of pharmacological properties. They are known as
IKK-β inhibitors,[2] A2A adenosine receptor antagonists[3] and potent inhibitor of HIV-1
integrase[4]
In spite of the fact that various methods have been reported for the synthesis of 2-amino-
3-cyano-4,6-diarylpyridine derivatives in the literature,[5-12] development of a facile, mild,
inexpensive, green and efficient approaches to access these compounds is still desirable.
Since the first report on the use of ionic liquids (ILs) as a catalyst in Friedel-Crafts
acylation,[13] they have attracted lots of attention because of their remarkable catalytic properties
as well as other applications such as using as a reaction medium.[14] Immobilization of ILs on the
solid supports[15] particularly mesoporous silica nanoparticles (MSNs) is highly desirable for
their versatile advantageous caused by heterogeneous support. It has been revealed that using
supported IL catalysts offer different advantageous such as convenient separation from reaction
mixture and easily use in gas-phase reaction.[16]
Recently, MSNs have been the center of attention due to well-defined pores possessing a
narrow diameter distribution, high pore volume, silanol functionalization opportunity, and
3
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
specific surface area.[17] Among the various MSNs, SBA-15 material has shown important
textural properties such as large specific surface areas (above 1000 m2·g−1), uniform-sized pores
(in range 4-30 nm), small crystallite size of primary particles, thick framework walls, and
complementary textural porosity.[18] These advantages have made SBA-15 a useful support with
high surface-to-volume ratio, variable framework compositions, and high thermal stability.[19]
Experimental
All reagents were purchased from Merck and Aldrich and used without further
1
purification. Melting points were taken on a Kofler hot stage apparatus and are uncorrected. H
NMR spectra were recorded on Bruker FT-400 using TMS as an internal standard.
Synthesis of ordered mesoporous SBA-15 silica
2D hexagonal SBA-15 was synthesized according to the literature.[20] The synthesis of
SBA-15 is briefed as follows: pluronic P123 (13.9 g) was dissolved in distilled water (252 g)
and concentrated HCl (7.7 g). After complete dissolution, TEOS (25.0 g) was added at once. The
mixture was left under stirring at 35 °C for 24 h, followed by hydrothermal treatment at 100 °C
for 48 h under static conditions. For template removal, the as-synthesized silica powders were
first shortly slurried in a mixture of ethanol-HCl and subsequently calcined at 550 °C for 2 hours.
4
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Synthesis of phosphine functionalized SBA-15
It was synthesized according to literature.[21] . SBA-15 (1 g) and triethylamine (4 mmol)
were added to a solution of chlorodiphenylphosphine (4 mmol) in dry CH2Cl2 (100 mL). The
mixture was refluxed under argon atmosphere for 12 h, then separated by filtration or centrifuge,
washed with CH2Cl2 (3×10 ml), and dried in vacuum at 60 °C for 12 h.
Synthesis of sulfonic acidic supported phosphonium ionic liquid functionalized SBA-15
[HO3S-PhospIL@SBA-15]
A solution of phosphine functionalized SBA-15 (1 g) and 1,4-butane sultone (4 mmol) in
toluene (50 mL) was refluxed overnight. The obtained solid was separated by filtration, washed
potently with methanol and acetone to remove the unreacted 1,4-butane sultone, and dried in
vacuum. Then, equivalent amounts of the later solid and p-TSA was heated at 70 °C for 24 h to
obtain the acidic catalyst with 4-methylbenzenesulfonate (p-TS-) counteranion.[22]
pH-analysis of [HO3S-PhospIL@SBA-15]
To an aqueous solution of NaCl (1 M, 25 mL) with an initial pH 5.93, the [HO3S-
PhospIL@SBA-15] (50 mg) was added and the resulting mixture stirred for 3 h when the pH of
solution decreased to ~1.0. This is equal to a loading of 1.97 mmol SO3H g-1 of catalyst.
Additionally, this result was confirmed by back-titration analysis of the catalyst.
5
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
General procedure for the synthesis of 2-amino-3-cyano-4,6-diarylpyridines derivatives 4
A mixture of chalcone derivative (1 mmol), malononitrile (1 mmol), ammonium acetate
(2 mmol), and [HO3S-PhospIL@SBA-15] (3 mg, 0.6 mol%) in EtOH (2 mL) was stirred at 50
°C. After completion of reaction (checked by TLC), the mixture was filtered off, washed with
boiling EtOH, and allowed to be recrystallized.
All compounds were known and their physical data were found to be identical compared with
those of reported in the literature.
2-Amino-4,6-diphenyl-nicotinonitrile 4a
mp 187-189 °C (186 °C [5]); 1H NMR (CDCl3, 400 MHz,): δH 5.21 (s, 2H, NH2), 7.22 (s, 1H,
H5), 7.30-7.48 (m, 6H, Ph), 7.60-7.65 (m, 2H, Ph), 8.12 (d, J = 7.6 Hz, 2H, Ph).
RESULTS AND DISCUSSION
The [HO3S-PhospIL@SBA-15] was characterized by different techniques including X-
ray powder diffraction (XRD), N2 adsorption–desorption analysis, FT-IR, transmission electron
microscopy (TEM), pH analysis, and back titration. The ion-exchange pH-analysis and back
titration demonstrated a loading of 1.97 mmol SO3H g-1 for the obtained [HO3S-PhospIL@SBA-
15]. XRD utilizes as a sensitive technique for the determination of ordered mesoporous
structures. As shown in Figure 1 a, the XRD pattern can be indexed to the reflections of the
SBA-15 structure. In SBA-15, the sharp peak related to the (100) diffraction has appeared at
2θ=0.97º along with two distinct shoulder peaks of (212) and (200) reflections at 1.47 and 1.70 º.
6
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
The aforementioned reflections in the XRD pattern confirm the 2D symmetry. Except for the
anticipated decrease in XRD peaks intensity, no significant changes were observed during the
functionalization. This confirms that the functionalization mainly accomplished inside of the
meso-channels. As it has been mentioned the positions of XRD peaks remained virtually fixed
which proved the retention of the meso-structure after functionalization. TEM were applied to
recognize the structural order of the extracted mesoporous solid SBA-15 (Figure 1b). In FTIR
Figure 1 c, characteristic absorption bands due to the stretching of Si-O-Si bond appear at 1090
cm−1 which overlapped with S–O and P–O stretching peaks. The stretching of S=O and C=C
groups in organic group appear at 1370 and 1679 cm−1, respectively. The stretching and out of
plane bending of acidic O–H group are observed at 3400–3500 and 800 cm−1, respectively.
As shown in Figure 1d the specific surface areas of the extracted SBA-15 and [HO3S-
PhospIL@SBA-15] are calculated by the multiple-point Brunauer–Emmett–Teller (BET) around
690.04 and 355.23 m2 g−1, respectively. Also the pore diameter distributions are determined
using BJH (Barrett–Joyner–Halenda) averaged ~3.2 and 1.8 nm, respectively. These results show
that the surface area and pore size have decreased after functionalization. Despite these
decreases, the shape of the hysteresis loop was typically identical. This observation confirms that
the pore shape does not significantly change during the modification process to prepare [HO3S-
PhospIL@SBA-15].
In continuation of our ongoing program on the design and synthesis of proficient
catalysts [23, 24] and also novel heterocycles;[25-27] herein, we have developed a user-friendly, high
yield, and economically and environmentally benign procedure for the synthesis of 2-amino-3-
7
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
cyano-4,6-diarylpyridines 4 through the reaction of different chalcones 1, malononitrile 2, and
ammonium acetate 3 using [HO3S-PhospIL@SBA-15] as a recyclable and environmentally
benign catalyst (Scheme 1).
In this context, we prepared SBA-15 material according to literature.[23] Subsequently, its
surface was modified through the reaction of the corresponding silica and
chlorodiphenylphosphine in the presence of triethyl amine in dry dichromethane. The later
compound was refluxed with a toluene solution of butane sultone leading to the formation of the
heterogenized zwitterion. To obtain the desired HO3S-Phosphonium based ionic liquid
functionalized SBA-15, it was treated with p-TSA. TEM image and the structure of the catalyst
were shown in Figure 2.
Next, we focused on the reaction of various chalcones 1, malononitrile 2, and ammonium
acetate 3 (Scheme 1). For this purpose, we selected the reaction of chalcone 1a malononitrile 2,
and ammonium acetate 3 as a model reaction to obtain the best reaction conditions. For the
accurate screening, the model reaction was conducted in various solvents and temperature in the
presence of different amount of catalyst. Some results are summarized in Table 1. AS can be
seen in Table 1, the best result was obtained in EtOH at 50 °C in the presence of 3 mg (0.6
mol%) catalyst. Under the optimized conditions, the related product 4a was obtained in 90%
yield.
At the end of the reaction, the catalyst was filtered, washed with hot diethyl ether, dried at
50 °C under vacuum for 1 h, and reused in another reaction. It is worth to mention that the
catalyst could be used for five times without an important change in its activity.
8
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
With these results in hand, we investigated the scope of our reaction with utilizing a
variety of chalcones bearing different substituents on the aromatic ring (Table 2). It was found
that chalcones possessing electron-donating as well as electron-withdrawing substituents
afforded high yields of products 4.
A proposed mechanism is depicted in Scheme 2. Probably, the Michael addition of
malononitrile 2 to activated chalcone derivative 1 leads to the formation of intermediate 5 which
tolerates reaction with ammonium acetate to form 6. Intramolecular cyclization reaction
following oxidation affords the title compounds 4. It is clear that all steps including increasing
the electrophilicity of the carbonyl groups as well as nitrile are catalyzed by the acidic catalyst.
CONCLUSION
In conclusion, various 2-amino-3-cyano-4,6-diarylpyridine derivatives were prepared
through the reaction of different chalcones, malononitrile, and ammoniumacetate in the presence
of green, recyclable, and efficient [HO3S-PhospIL@SBA-15] in EtOH at 50 °C. The important
advantages offered by this protocol are high yields of products, user-friendly procedure including
simple isolation and purification of the products, using environmentally friendly solvent and
recyclability of catalyst. It should be noted that the catalyst could be easily separated and reused
free times without significant reduction in activity.
9
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
ACKNOWLEDGEMENT
The authors gratefully acknowledge the Research Council of Kerman University of
Medical Sciences and Iran National Science Foundation (INSF).
10
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
REFERENCES
1. Chaubey, A.; Pandey, S.N. Asian J. Pharm. Clin. Res. 2001, 4, 5.
2. Murata, T.; Shimada, M.; Sakakibara, S.; Yoshino, T.; Kadono, H.; Masuda, T.; Shimazaki,
M.; Shintani, T.; Fuchikami, K.; Sakai, K.; Inbe, H.; Takeshita, K.; Niki, T.; Umeda, M.;
Bacon, K.B.; Ziegelbauer, K.B.; Lowinger, T.B. Bioorg. Med. Chem. Lett. 2003, 13, 913.
3. Mantri, M.; De Graaf, O.; Van Veldhoven, J.; Göblyös, A.; Von Frijtag Drabbe Künzel,
J.K.; Mulder-Krieger, T.; Link, R.; De Vries, H.; Beukers, M.W.; Brussee, J.; Ijzerman, A.P.
J. Med. Chem. 2008, 51, 4449.
4. Deng, J.; Sanchez, T.; Al-Mawsawi, L.Q.; Dayam, R.; Yunes, R.A.; Garofalo, A.; Bolger,
M.B.; Neamati, N. Bioorg. Med. Chem. 2007, 15, 4985.
5. Gupta, R.; Jain, A.; Jain, M.; Joshi, R. Bull. Korean Chem. Soc. 2010, 31, 3180.
6. Safari, J.; Banitaba, S.H.; Khalili, S.D. Ultrason. Sonochem. 2012, 19, 1061.
7. Tang, J.; Wang, L.; Yao, Y.; Zhang, L.; Wang, W. Tetrahedron Lett. 2011, 52, 509.
8. Sarda, S.R.; Kale, J.D.; Wasmatkar, S.K.; Kadam, V.S.; Ingole, P.G.; Jadhav, W.N.; Pawar,
R.P. Mol. Divers 2009, 13, 545.
9. Prakash, L.; Verma, S.S.; Shahla, Tyagi, E.; Mital, R.L. J. Fluorine Chem. 1988, 41, 303.
10. Vyas, D.H.; Tala, S.D.; Akbari, J.D.; Dhaduk, M.F.; Joshi, K.A.; Joshi, H.S. Indian J.
Chem. 2009, 48B, 833.
11. Gothwal, R.; Malhotra, G.; Srivastava, Y.K. E-J. Chem. 2011, 8, 119.
11
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
12. Samshuddin, S.; Narayana, B.; Sarojini, B.K.; Yathirajan, H.S.; Raghavendra, R. Der
Pharma. Chemica 2012, 4, 1445.
13. Boon, J.A.; Levinsky, J.A.; Pflug, J.L.; Wilkes, J.S. J. Org. Chem. 1986, 51, 480.
14. Petkovic, M.; Seddon, K.R.; Petkovic, M.; Seddon, K.R.; Rebelo, L.P.N.; Pereira, C.S.
Chem. Soc. Rev. 2011, 40, 1383.
15. Valkenberg, M.H.; deCastro, C.; Hölderich, W.F. Green Chem. 2002, 4, 88.
16. Öchsner, E.; Schneider, M.J.; Meyer, C.; Haumann, M.; Wasserscheid, P. Appl. Catal. A:
Gen. 2011, 399, 35.
17. Beck, J.S.; Vartuli, J.C.; Roth, W.J.; Leonowicz, M.E.; Kresge, C.T.; Schmitt, K.D.; Chu,
C.T-W.; Olson, D.H.; Sheppard, E.W.; McCullen, S.B.; Higgins, J.B.; Schlenkert, J.L. J.
Am. Chem. Soc. 1992, 114, 10834.
18. Huirache-Acuña, R.; Nava, R.; Peza-Ledesma, C.L.; Lara-Romero, J.; Alonso-Núñez, G.;
Pawelec, B.; Rivera-Muñoz, E.M. Materials 2013, 6, 4139.
19. Rahmat, N.; Zuhairi, A.A.; Mohamed, A.R. Am. J. Appl. Sci. 2010, 7, 1579.
20. Choi, M.; Heo, W.; Kleitz, F.; Ryoo, R. Chem. Commun. 2003, 1340.
21. Khalafi-Nezhad, A.; Panahi, F. J. Organomet. Chem. 2013, 741-742, 7.
22. Cole, A.C.; Jensen, J.L.; Ntai, I.; Tran, K.L.T.; Weaver, K.J.; Forbes, D.C.; Davis, Jr. J.H. J.
Am. Chem. Soc. 2002, 124, 5962.
23. Jalili-Baleh, L.; Mohammadi, N.; Khoobi, M.; Ma’mani, L.; Foroumadi, A.; Shafiee, A.
Helv. Chim. Acta 2013, 96, 1601.
24. Khoobi, M.; Ma’mani, L.; Rezazadeh, F.; Zareie, Z.; Foroumadi, A.; Ramazani, A.; Shafiee,
A. J. Mol. Catal. A: Chem. 2012, 359, 74.
12
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
25. Hosseini-Zare, M.S.; Mahdavi, M.; Saeedi, M.; Asadi, M.; Javanshir, S.; Shafiee, A.;
Foroumadi, A. Tetrahedron Lett. 2012, 53, 3448.
26. Zonouzi, A.; Mirzazadeh, R.; Safavi, M.; Ardestani, S.K.; Emami, S.; Foroumadi, A. Iran J.
Pharm. Res. 2013, 12, 679.
27. Alipour, E.; Mousavi, Z.; Safaei, Z.; Pordeli, M.; Safavi, M.; Firoozpour, L.;
Mohammadhosseini, N.; Saeedi, M.; Ardestani, S.K.; Shafiee, A.; Foroumadi, A. Daru J.
Pharm. Sci. 2014, 22, 41.
13
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
TABLE 1 Optimization of the reaction conditionsa
Entry
Solvent
H2O
Temperature (°C) Amount of catalyst (mg) Time (h)
Yield (%)b
1
2
3
4
rt
reflux
rt
4
4
3
3
24
12
12
8
NR
NR
50
H2O
EtOH
EtOH
50
90
5
6
7
CH3CN
CH3CN
PhMe
50
50
5
3
4
8
8
8
75
70
reflux
NR
8
DMF
80
3
8
45
a
Carried out with chalcone 1a, malononitrile 2, and ammonium acetate 3 in the presence of
[HO3S-PhospIL@SBA-15].
b Isolated yields.
14
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
TABLE 2 Synthesis of 2-amino-3-cyano-4,6-diarylpyridines 4
Ar
Ar'
Product 4
mp (°C)
Entry
Yield (%)a
Observed
187-189
Reported
186[5]
C6H5
C6H5
C6H5
90
85
90
85
88
90
82
80
82
85
85
83
80
80
4a
4b
4c
4d
4e
4f
1
2
4-Cl-C6H4
4-MeO-C6H4
4-Me-C6H4
3-NO2-C6H4
4-F-C6H4
C6H5
188-190
190-192
172-174
231-232
205-208
183-185
180-181
179-180
178-180
174-176
183-185
155-157
194-195
190[5]
192-195[6]
175-176[7]
227-230[7]
204-206[12]
182[5]
C6H5
3
C6H5
4
C6H5
5
4-F-C6H4
4-Cl-C6H4
4-Cl-C6H4
4-Cl-C6H4
4-BrC6H4
4-BrC6H4
4-BrC6H4
4-MeO-C6H4
4-MeO-C6H4
6
4g
4h
4i
7
4-MeO-C6H4
4-F-C6H4
C6H5
177[5]
8
181[5]
9
175[5]
4j
10
11
12
13
14
4-F-C6H4
4-MeO-C6H4
4-MeO-C6H4
4-Cl-C6H4
172[5]
4k
4l
181[5]
159-160[7]
195-196[7]
4m
4n
aIsolatd yields.
15
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Fig. 1. XRD pattern (a), TEM (b), FTIR spectra (c), and N2 adsorption-desorption
analysis of SBA-15 and [HO3S-PhospIL@SBA-15].
16
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
O
Ph
P
+
Ph
p-TS-
HO3S
-
p-TS
Ph
Ph
+
P
SO3H
O
Fig. 2. Sulfonic acid supported phosphonium based ionic liquid functionalized SBA-15 [HO3S-
PhospIL@SBA-15].
17
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 1. Synthesis of 2-amino-3-cyano-4,6-diarylpyridines 4.
18
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 2. Proposed mechanism for the formation of 2-amino-3-cyano-4,6-diarylpyridines 4.
19
ACCEPTED MANUSCRIPT