Magnetic cellulose/Ag as a novel eco-friendly nanobiocomposite to catalyze synthesis of chromene-linked nicotinonitriles

Article abstract of DOI:10.1016/j.carbpol.2016.09.002

In this work, design, preparation and performance of magnetic cellulose/Ag nanobiocomposite as a recyclable and highly efficient heterogeneous nanocatalyst is described. Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) pattern, vibrating sample magnetometer (VSM) curve, field-emission scanning electron microscopy (FE-SEM) image, energy dispersive X-ray (EDX) analysis and thermogravimetric analysis/differential thermal analysis (TGA/DTA) were used for the characterization. Then, its activity was investigated in the synthesis of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitrile derivatives. The main advantages of the reaction are high yields and short reaction times. The remarkable magnetic property of the nanobiocomposite catalyst provides easy separation from the reaction mixture by an external magnet without considerable loss of its catalytic activity.

Full text of DOI:10.1016/j.carbpol.2016.09.002

Accepted Manuscript
Title: Magnetic cellulose/Ag as a novel eco-friendly
nanobiocomposite to catalyze synthesis of chromene-linked
nicotinonitriles
Author: Ali Maleki Hamed Movahed Parisa Ravaghi
PII:
S0144-8617(16)31056-6
DOI:
Reference:
http://dx.doi.org/doi:10.1016/j.carbpol.2016.09.002
CARP 11529
To appear in:
Received date:
Revised date:
Accepted date:
16-6-2016
1-9-2016
2-9-2016
Please cite this article as: Maleki, Ali., Movahed, Hamed., & Ravaghi,
Parisa., Magnetic cellulose/Ag as a novel eco-friendly nanobiocomposite to
catalyze synthesis of chromene-linked nicotinonitriles.Carbohydrate Polymers
http://dx.doi.org/10.1016/j.carbpol.2016.09.002
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Magnetic cellulose/Ag as a novel eco-friendly nanobiocomposite to
catalyze synthesis of chromene-linked nicotinonitriles
Ali Maleki* maleki@iust.ac.ir, Hamed Movahed, Parisa Ravaghi
Department of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, Iran
* Corresponding author. Tel.: +98 21 77240540; fax: +98 21 73021584.
Graphical Abstract
Highlights
•
•
A new, green and magnetic cellulose/Ag nanobiocomposite catalyst was introduced.
The new nanocatalyst was characterized by FT-IR, EDX, FE-SEM, VSM and
TGA/DTA.
•
•
It was efficiently applied in the synthesis of chromene-linked nicotinonitriles.
The heterogeneous nanocatalyst was simply recovered and reused for several times.
Abstract
In this work, design, preparation and performance of magnetic cellulose/Ag nanobiocomposite as a
recyclable and highly efficient heterogeneous nanocatalyst is described. Fourier transform infrared
(FT-IR) spectroscopy, X-ray diffraction (XRD) pattern, vibrating sample magnetometer (VSM) curve,
field-emission scanning electron microscopy (FE-SEM) image, energy dispersive X-ray (EDX) analysis
and thermogravimetric analysis/differential thermal analysis (TGA/DTA) were used for the
characterization. Then, its activity was investigated in the synthesis of 2-amino-6-(2-oxo-2H-
chromen-3-yl)-4-phenylnicotinonitrile derivatives. The main advantages of the reaction are high
yields and short reaction times. The remarkable magnetic property of the nanobiocomposite catalyst
provides easy separation from the reaction mixture by an external magnet without considerable loss
of its catalytic activity.
Keywords: Cellulose/Ag nanobiocomposite; Magnetic nanocatalyst; Cyanopyridine; Chromene-linked
nicotinonitrile; Recyclability.
1. Introduction

Eco-friendly protocols are processes that include developing green materials and safe conditions such
as using biodegradable polymers and complete biological components for waste reduction. As a
result, biopolymers have attracted both academic and industrial interests (Sinha Ray, 2013). Cellulose
production reaches to approximately 700 billion tons each year (Xu, Chen, Rosswurm, Yao, &
Janaswamy, 2016). Diverse benefits of cellulose such as biocompatibility, biodegradability and low
toxicity make it a good alternative to petroleum byproducts (Klemm, Heublein, Fink, & Bohn, 2005).
Biopolymers and inorganic materials affected and improved the multifunctional properties of
cellulose-based hybrids (Dong, Deng, et al., 2014). Lately, as a sustainable alternative of fossil feed
stocks, lignocelluloses have attracted considerable attentions of researchers (Dong, Li, Ma, Yao, &
Sun, 2014). The most plentiful biopolymer on the Earth is cellulose that can be used as an eco-
friendly polymer (Khalil, Bhat, & Yusra, 2012, Y. Feng, Zhang, He, & Zhang, 2016, Li et al., 2015).
Nevertheless, it is not easy to use cellulose as a matrix of polymer composites. Cellulose is neither
meltable nor soluble in common solvents. Therefore, developing new methods to solve cellulose are
required to utilize the natural cellulose (Hameed, Guo, Tay, & Kazarian, 2011; X. Zhang, Liu, Zheng,
& Zhu, 2012). Biopolymers are one of the most prevalent options to produce polymeric
nanocomposites with diverse applications (Kushwaha, Avadhani, & Singh, 2015; Singh & Kushwaha,
2013; Song et al., 2015). Also, the separation of these kind of nanocomposites from the reaction
media could be fast and easy (Kalkan, Aksoy, Aksoy, & Hasirci, 2012; Shi, Ma, Han, Zhang, & Yu,
2014; Wang, Guo, Yang, & Liu, 2010, Klemm, Heublein, Fink, & Bohn, 2005, Fu, Yao, Shi, Ma, &
Zhao, 2014). Accordingly, many researches have focused in this area.
To reach the specific purposes, metal nanocomposites can be used in large scale. Silver-based
nanocomposites have a wide verity of applications in different fields such as textile (Agarwal, Garg,
Kashyap, & Chauhan, 2015), biosensor (D.Q. Feng, Liu, & Wang, 2015), water treatment (Ramana,
Yu, & Seshaiah, 2013; Sumesh, Bootharaju, & Pradeep, 2011), wood dressing (Chakraborty &
Mascharak, 2015) and food packaging (Bott & Tadjiki, 2013). Recently, a magnetic antimicrobial
nanocomposite based on bacterial cellulose and silver nanoparticles has been reported (Sureshkumar,
Siswanto, & Lee, 2010). They have used dopamine as a coating agent on the bacterial cellulose to
stabilize the antibacterial Ag nanoparticles. However, there have been some problems such as
expensive preparation method and considerable loss of the magnetic properties.
In recent years, using nanocomposites in organic reactions as catalysts is a fast-growing field.
Pyridine is one of the most important heterocyclic structures in organic chemistry. The cyanopyridine
scaffold exists in many naturally occurring and synthetic compounds (Banothu, Bavantula, & Crooks,
2013). Moreover, 3-cyanopyridine derivatives play a significant role in the pharmaceutical industries,
because of their wide range of applications such as antitumor, analgesic, anti-inflammatory,
antipyretic, antimicrobial and cardiotonic activities (Bekhit & Baraka, 2005; Manna et al., 1992; F.
Zhang et al., 2011). Various techniques have been developed for the synthesis of coumarin The
improvement of effective coumarins synthetic methods are highly important in synthetic and
medicinal chemistry (Ghashang, Aswin, & Mansoor, 2013, Zhou, Gong, & Zhu, 2009; Zhou, Song,
Lv, Gong, & Tu, 2009). In connection with our previous works on magnetic nanobiocomposite
catalysts (Maleki & Kamalzare, 2014; Maleki, Movahed, & Paydar, 2016; Maleki & Paydar, 2015),
herein, we first synthesized 3-acetylecoumarin 3 from the reaction of salicylaldehyde 1 and methyl
acetoacetate 2 in the presence of a catalytic amount of dimethylamine (Scheme 1). Then, the
compound 3 was used as a starting material beside aryl aldehydes 4, malononitrile 5 and ammonium
acetate 6 in a multicomponent reaction which led to the formation of 2-amino-6-(2-oxo-2H-chromen-
3-yl)-4-phenylnicotinonitrile derivatives 7a-l in the presence of a catalytic amount of magnetic
cellulose/Ag nanobiocomposite.

There are two major novelties in the present nanocatalyst including the structure and the procedure of
the production. In the synthesized magnetic cellulose/Ag nanobiocomposite, γ-Fe2O3 nanoparticles
were supported into the cellulose layers and Ag nanoparticles were immobilized on the surface of the
cellulose. In addition, this procedure have some further advantages such as simple catalyst
recyclability, inexpensive catalyst, environmentally friendly procedure, short reaction times, avoiding
hazardous organic solvents and high yields of the products.
2. Experimental
2.1. General
All the solvents, chemicals and reagents were purchased from Merck, Fluka and Aldrich. Melting
points were measured on an Electrothermal 9100 apparatus and are uncorrected. FT-IR spectra were
1
recorded on a Shimadzu IR-470 spectrometer by using KBr pellet. H and 13C NMR spectra were
recorded on a Bruker DRX-500 Avance spectrometer at 500 and 125 MHz, respectively. FE-SEM
images were obtained on a Sigma Zeiss. EDX spectra were recorded on Numerix DXP–X10P. XRD
measurements were carried out by using a JEOL JDX–8030 (30 kV, 20 mA). TGA and DTA were
measured by a STA504. Magnetic susceptibility measurements were performed by using a Lake Shore
VSM 7410. The known products were identified by comparison of their spectroscopic and analytical
data with authentic samples.
2.1. Preparation of magnetic cellulose/Ag nanobiocomposite
First, poly(ethyleneglycol) (PEG-2000) (0.5 g) and NaOH (4.0 g) were added to distillated water (45
mL) to achieve an aqueous solution of PEG/NaOH. Then, 1.0 g of cellulose was added to the mixture
and swelled for 3 h at room temperature to obtain white suspension. To solve cellulose suspension, it
was cooled down to -15 °C and was held in this temperature overnight (12 h) until it became a solid
frozen mass. The frozen solid was placed at room temperature under strong stirring until
homogeneous cellulose solution was obtained (Yan & Gao, 2008). Next, 2.25 g of FeCl3.6H2O and
0.75 g of FeCl2.4H2O were dissolved in 15 mL distilled water and the solution was stirred vigorously
at room temperature. After that, the solution was added dropwise into the prepared cellulose solution
during 2.5 h. The resultant magnetized cellulose was filtered and washed with distilled water to
eliminate chloride ions. Then, the obtained composite was loaded into 50 mL distilled water and
stirred for 2 h. Also, 0.1 g of poly(vinylpyrrolidinone) (PVP) was added as a stabilizer to 10 mL of
AgNO3 solution (0.05 M). This solution was added to the previous solution of composite and the
resulted mixture was stirred for 30 min. After that, 5 mL of NaBH4 was added dropwise within 2 h to
this mixture. Finally, the resultant magnetic cellulose/Ag nanobiocomposite was washed with water
for several times and was dried at room temperature.
2.3. Synthesis of 3-acetylcoumarin
A mixture of salicylaldehyde 1 (1 mmol) and methyl acetoacetate 2 (1 mmol) in the presence of a
catalytic amount of dimethylamine (10 mol%) in 2 mL distilled water was stirred for 2 min at room
temperature to form pale yellow precipitate. Then, it was filtered, washed several times with distilled
water and recrystallized from ethanol (96%) to give pure 3-acetylcoumarin 3.
2.4. Synthesis of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitriles

3-Acetylcoumarin 3 (1 mmol), aryl aldehydes 4 (1 mmol), malononitrile 5 (1 mmol), ammonium
acetate 6 (1.5 mmol) and magnetic cellulose/Ag nanobiocomposite (0.15 g) were added to a container
which has 5 mL EtOH. The reaction mixture was stirred for an appropriate time (as indicated in Table
2). The progress of the reaction was monitored by TLC. After completion of the reaction, the solid
material was filtered and then dissolved in hot ethyl acetate. After removing the catalyst by an external
magnetic bar, pure 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitriles 7a-l were obtained.
2.5. Spectral data of the synthesized compounds
2-Amino-6-(2-oxo-2H-chromen-3-yl)-4-(3-nitro-phenyl)nicotinonitrile (7b)
IR (KBr, cm-1): 3363 and 3244 (NH2), 3083 (ArH), 2212 (CN), 1728 (C=O), 1572 and 1346 (NO2). 1H
NMR (500 MHz, DMSO-d6) δ, ppm: 7.07 (s, 2H, NH2), 7.11 (s, 1H, coumarin 4-H), 7.45 (s, 1H, PryH),
7.47-7.54 (m, 2H, ArH), 7.84-7.89 (m, 2H. ArH), 8.30-8.48 (m, 4H, ArH). 13C NMR (125 MHz,
DMSO-d6) δ, ppm: 96.1, 115.9, 116.3, 117.1, 119.3, 120.1, 124.2, 125.1, 125.5, 125.9, 125.9, 130.0,
131.3, 133.9, 136.0, 139.4, 145.1, 148.2, 148.7, 154.2, 154.3, 159.2.
2-Amino-6-(2-oxo-2H-chromen-3-yl)-4-(4-choloro-phenyl)nicotinonitrile (7d)
1
IR (KBr, cm-1) 3340 and 3234 (NH2), 3083 (ArH), 2212 (CN), 1722 (C=O). H NMR (500 MHz,
DMSO-d6) δ, ppm: 6.69 (s, 1H, coumarin 4-H), 6.99 (s, 2H, NH2), 7.43-7.78 (m, 8H, ArH), 8.39 (s, 1H,
PryH).
3. Results and discussion
3.1. Morphological characterization
To determine the size and distribution of the nanoparticles, FE-SEM images analysis was used. As
can be seen in Figs. 1a, b, nanoparticles have the spherical morphology and were dispersed properly
on cellulose surface. FE-SEM image of cellulose (without modification) is shown in Fig. 1c, which
have uniform and flat surface before the stabilization of the nanoparticles. To determine the size of the
nanoparticles, 90 particles were used randomly. The particle size distribution was narrow and the
sizes of most of the particles were about 20-25 nm (Fig. 1d). In addition, the average size of the
nanoparticles was about 27.56 nm.
3.2. The X-ray powder diffraction
The XRD pattern of magnetic cellulose/Ag nanobiocomposite was illustrated in Fig. 2a. As it can be
seen, the peaks of the Ag nanoparticles at 2θ = 38.1˚ (1 1 1), 44.2˚ (2 0 0), 64.4˚ (2 2 0), 77.4˚ (3 1 1)
are in good agreement with the well-crystallized silver (JCPDS 04-0783 Fig. 2b). Furthermore, at the
XRD pattern of the prepared γ-Fe2O3, the position of all diffraction peaks match well with those of a
lattice cubic system of γ-Fe2O3 peaks (JCPDS 25-1402 Fig. 2c) at 2θ = 30.2˚ (2 0 6), 35.6˚ (1 1 9),
57.4˚ (1 1 15) and 63.0˚ (4 0 12). The peak presented at 2θ around 20 is related to the cellulose.
According to the XRD patterns of magnetic cellulose/Ag nanobiocomposite, it can be found that in
addition to γ-Fe2O3 peaks, all added peaks are in good agreement with well-crystallized silver.
3.3 .The elemental analysis
The elemental analysis of the magnetic cellulose/Ag nanobiocomposite has been carried out by using
EDX mapping technique. The percentage of carbon, oxygen, iron, silver and gold obtained from EDX
analysis are shown in Fig. 3a. In these results, Au existence in the nanocomposite is due to its

implementation as a coating for material conductivity, Ag is due to Ag nanoparticles, Fe is due to iron
oxide and carbon and oxygen are originated from cellulose.
To determine the dispersion of elements on nanobiocomposite, SEM-EDX mapping was used. The
homogeneity of chemical composition determined by SEM–EDX mapping is presented in Fig. 2(b–f).
The elemental mapping images equal with the corresponding SEM images. The results show that Ag
nanoparticles are distributed uniformly, which approves good dispersion of nanoparticles in the matrix
surface.
3.4. Magnetic characterization
Vibrating sample magnetometer of the magnetic cellulose/Ag nanobiocomposite was shown in Fig. 4.
It indicates that the sample was superparamagnetic with small hysteresis loop at room temperature
(soft magnetic). The magnetic saturation (Ms) value of the magnetic cellulose/Ag nanobiocomposite
was about 6.2 emu g-1, which was good enough to be easily recycled from the liquid reaction mixture.
Therefore, it could have promising applications as a renewable catalyst.
3.5. The thermal stability of the magnetic cellulose/Ag nanobiocomposite
TGA/DTA was used to study the thermal stability of the magnetic cellulose/Ag nanobiocomposite.
TGA and DTA curves of the magnetic cellulose/Ag nanobiocomposite are shown in Fig. 5. The
decomposition of a tiny amount of cellulose in the nanocomposite was observed below 250–260 °C.
Another weight loss was seen at 300–320 °C which is attributed to decomposition of the other
impurities. Major weight loss was occurred at 370–410 °C which is attributed to organic materials
decomposition of the nanobiocomposite. This weight loss temperature was in contrast with cellulose
weight loss temperature that is about 250–260 °C. As a result, its thermal stability has been
significantly improved.
3.6. Application of the nanocatalyst in organic synthesis
The application of the nanocatalyst was investigated in the synthesis of 2-amino-6-(2-oxo-2H-
chromen-3-yl)-4-phenylnicotinonitrile starting from 3-acetylcoumarin (1 mmol), malononitrile (1
mmol), 3-nitro-benzaldehyde (1 mmol) and ammonium acetate (1.5 mmol).
In order to optimize the reaction conditions, various amounts of the nanocatalyst, temperatures and
solvents were investigated (Table 1). The completions of the reactions were monitored by TLC. First
of all, the amount of the nanocatalyst was altered from 0.05 g up to 0.2 g. Our studies showed that
when less than 0.15 g of the nanocatalyst was applied, lower yields of the corresponding products
were resulted (Table 1, entries 2 and 3). Also, when more than 0.15 g of the nanocatalyst was used, no
improvement in the yield of the reaction was observed (Table 1, entry 5). In the absence of the
nanocatalyst, the yield of the product was only trace (Table 1, entry 1). As a result, 0.15 g of the
nanocatalyst was chosen as the optimized amount of the nanocatalyst (Table 1, entry 4).
Furthermore, to investigate the effect of the nanocatalyst species, cellulose, magnetic cellulose and
cellulose/Ag nanocomposite were separately used as a catalyst. The results show that, Ag and Fe2O3
nanoparticles had the most effective role in the reaction. Indeed, cellulose has just been used as a bio
matrix in the magnetic cellulose/Ag nanocomposite (Table 1, entries 6-8). As well as, to optimize

solvent of the reaction, various polar solvents such as H2O, ethanol and acetonitrile and a nonpolar
solvent (dichloromethane) were examined. Finally, based on the results, ethanol was found to be the
most suitable solvent (Table 1, entries 11-13). To optimize the reaction temperature, the reaction was
performed at 25, 60 and 78 ˚C (refluxing). Based on the results, 60 ˚C was selected as the best
temperature to give high yields (Table 1, entries 9-10).
To explore the scope and limitations of the reaction and also efficiency of the magnetic cellulose/Ag
nanobiocomposite, various substituted aromatic aldehydes bearing both electron-withdrawing and
electron-releasing groups were chosen and performed under optimum conditions (Table 2). All cases
were reacted successfully and gave the products in high yields. It was found that, the aromatic
aldehydes including electron-withdrawing groups reacted faster than those included electron-releasing
groups.
A possible mechanism of the reaction is shown in Scheme 2. First, methylacetoacetate was activated
by dimethylamine as a base. Then, a Knoevenagel condensation occurs between salicylaldehyde 1 and
methylacetoacetate 2, followed by a cyclization reaction to obtain 3-acethylcumarine 3. Second, the
ammonia obtained from ammonium acetate 6, as nitrogen source, attacks to ketone 3 (3-
acethylcumarine). The reaction was improved by imine-enamine tautomerization. Subsequently,
another Knoevenagel condensation reaction was carried out between malononitrile 5 and an aryl
aldehyde 4. The catalyst activates both carbonyl groups in the second step as a Lewis acid. Also, both
of the intermediates (a, b) were characterized by FT-IR. Finally, the intermediates (a, b) were reacted
together by Michael condensation to result intermediate (c) (Ghashang et al., 2013). In the
intermediate (c), imine to enamine tautomerization, cycloaddition and aromaticity reaction was
progressed by atmospheric oxygen. The synthesis of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-
phenylnicotinonitrile in the presence of catalytic amount of magnetic cellulose/Ag nanobiocomposite
was done under two conditions which were included under inert atmosphere and also in the presence
of air (O2). The results indicated that the reaction was not completed under inert conditions. But, it was
preceded under aerobic oxidation conditions.
3.7. Catalyst recycling
An important parameter in heterogeneous catalysis is the reusability of the catalyst. Hence, a set of
experiments was performed to check the reusability of the present nanocatalyst for the synthesis of 2-
amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitrile 7b. Due to magnetic properties, the
catalyst was easily separated, washed three times with ethanol and acetone; and reused efficiently for
at least five times without significant loss in its activity (Fig. 4b and Table 2, entry 2).
4. Conclusions
In summary, we have prepared and characterized an efficient magnetic cellulose/Ag
nanobiocomposite. Various analytical techniques were used to characterize the nanocatalyst. FE-SEM
images of the nanobiocomposite was indicated that the sizes of most of the particles were about 20-25
nm. XRD pattern showed that all peaks are in agreement with well-crystallized silver. The EDX
analysis clearly showed that there are Fe, Ag, C and O elements in the nanobiocomposite. In addition,

to investigate the application of the nanobiocomposite, for the first time, it was used as an efficient
nanocatalyst in the synthesis of chromene-linked nicotinonitriles. 2-Amino-6-(2-oxo-2H-chromen-3-
yl)-4-arylnicotinonitrile derivatives were efficiently synthesized in the presence of the present
heterogeneous nanocatalyst via a one-pot four-component condensation of 3-acetylcoumarin,
aldehydes, malononitrile and ammonium acetate in EtOH at 60˚. The superparamagnetic catalyst was
successfully removed from the reaction mixture by an external magnet. Therefore, it could have
promising applications as a recyclable and renewable catalyst in industrial large-scale production. In
addition, this procedure had some further advantages such as simple catalyst recyclability,
inexpensive catalyst, environmentally friendly procedure, short reaction times, avoiding hazardous
organic solvents and high yields of the products.
Acknowledgements
The authors gratefully acknowledge partial support from the Research Council of the Iran University
of Science and Technology.
References
Agarwal, R., Garg, N., Kashyap, S. R., & Chauhan, R. P. (2015). Antibacterial finish of textile using
papaya peels derived silver nanoparticles. Indian Journal of Fibre & Textile Research (IJFTR),
40(1), 105–107.
Banothu, J., Bavantula, R., & Crooks, P. A. (2013a). Facile one-pot multicomponent synthesis of 2-
amino-6-(2-oxo-2H-chromen-3-yl)-4-arylpyridine-3-carbonitriles using Brønsted acidic ionic
liquid as catalyst under solvent-free conditions. Iranian Journal of Catalysis, 3(1), 41–47.
Banothu, J., Bavantula, R., & Crooks, P. A. (2013b). Ournal of, 3(1), 41–47.
Bekhit, A. A., & Baraka, A. M. (2005). Novel milrinone analogs of pyridine-3-carbonitrile derivatives
as promising cardiotonic agents. European Journal of Medicinal Chemistry, 40(12), 1405–1413.
Bott, J., & Tadjiki, S. (2013). Field-Flow Fractionation Supporting Consumer Safety Evaluation of
Silver Nanoparticle Applications in Food Packaging Polymers. AMERICAN LABORATORY,
45(4), 9–12.
Chakraborty, I., & Mascharak, P. K. (2015). Design and construction of a silver (I)-loaded cellulose-
based wound dressing: trackable and sustained release of silver for controlled therapeutic
delivery to wound sites. Journal of Materials Science: Materials in Medicine, 26(10), 1–9.
Dong, Y.-Y., Deng, F., Zhao, J.-J., He, J., Ma, M.-G., Xu, F., & Sun, R.-C. (2014). Environmentally
friendly ultrosound synthesis and antibacterial activity of cellulose/Ag/AgCl hybrids.
Carbohydrate Polymers, 99, 166–72.
Dong, Y.-Y., Li, S.-M., Ma, M.-G., Yao, K., & Sun, R.-C. (2014). Compare study cellulose/Ag
hybrids using fructose and glucose as reducing reagents by hydrothermal method. Carbohydrate
Polymers, 106, 14–21.

Feng, D.-Q., Liu, G., & Wang, W. (2015). A novel biosensor for copper (ii) ions based on turn-on
resonance light scattering of ssDNA templated silver nanoclusters. Journal of Materials
Chemistry B, 3(10), 2083–2088.
Feng, Y., Zhang, J., He, J., & Zhang, J. (2016). Transparent cellulose/polyhedral oligomeric
silsesquioxane nanocomposites with enhanced UV-shielding properties. Carbohydrate
Polymers, 147, 171–7.
Ghashang, M., Aswin, K., & Mansoor, S. S. (2013). An eco-friendly catalytic route for one-pot
synthesis of 2-amino-6-(2-oxo-2Hchromen-3-yl)-4-arylnicotinonitrile derivatives by silica-
supported perchloric acid (HClO4–SiO2) under solvent-free conditions. Research on Chemical
Intermediates, 40(3), 1135–1145.
Hameed, N., Guo, Q., Tay, F. H., & Kazarian, S. G. (2011). Blends of cellulose and poly (3-
hydroxybutyrate-co-3-hydroxyvalerate) prepared from the ionic liquid 1-butyl-3-
methylimidazolium chloride. Carbohydrate Polymers, 86(1), 94–104.
Kalkan, N. A., Aksoy, S., Aksoy, E. A., & Hasirci, N. (2012). Preparation of chitosan‐coated
magnetite nanoparticles and application for immobilization of laccase. Journal of Applied
Polymer Science, 123(2), 707–716.
Khalil, H. P. S. A., Bhat, A. H., & Yusra, A. F. I. (2012). Green composites from sustainable cellulose
nanofibrils: a review. Carbohydrate Polymers, 87(2), 963–979.
Klemm, D., Heublein, B., Fink, H., & Bohn, A. (2005). Cellulose: fascinating biopolymer and
sustainable raw material. Angewandte Chemie International Edition, 44(22), 3358–3393.
Kushwaha, O. S., Avadhani, C. V, & Singh, R. P. (2015). Preparation and characterization of self-
photostabilizing UV-durable bionanocomposite membranes for outdoor applications.
Carbohydrate Polymers, 123(2015), 164–173.
Li, M.-C., Wu, Q., Song, K., Lee, S., Qing, Y., & Wu, Y. (2015). Cellulose nanoparticles: structure–
morphology–rheology relationships. ACS Sustainable Chemistry & Engineering, 3(5), 821–832.
Maleki, A., & Kamalzare, M. (2014). Fe3O4@ cellulose composite nanocatalyst: preparation,
characterization and application in the synthesis of benzodiazepines. Catalysis Communications,
53, 67–71.
Maleki, A., Movahed, H., & Paydar, R. (2016). Design and development of a novel cellulose/γ-
Fe2O3/Ag nanocomposite: a potential green catalyst and antibacterial agent. RSC Advances,
6(17), 13657–13665.
Maleki, A., & Paydar, R. (2015). Graphene oxide–chitosan bionanocomposite: a highly efficient
nanocatalyst for the one-pot three-component synthesis of trisubstituted imidazoles under
solvent-free conditions. RSC Advances, 5(42), 33177–33184.
Manna, F., Chimenti, F., Bolasco, A., Filippelli, A., Palla, A., Filippelli, W., … Mercantini, R. (1992).
Anti-inflammatory, analgesic and antipyretic 4, 6-disubstituted 3-cyanopyridine-2-ones and 3-
cyano-2-aminopyridines. European Journal of Medicinal Chemistry, 27(6), 627–632.
Ramana, D. K. V., Yu, J. S., & Seshaiah, K. (2013). Silver nanoparticles deposited multiwalled
carbon nanotubes for removal of Cu (II) and Cd (II) from water: Surface, kinetic, equilibrium,
and thermal adsorption properties. Chemical Engineering Journal, 223, 806–815.

Shi, L., Ma, F., Han, Y., Zhang, X., & Yu, H. (2014). Removal of sulfonamide antibiotics by oriented
immobilized laccase on Fe 3 O 4 nanoparticles with natural mediators. Journal of Hazardous
Materials, 279, 203–211.
Singh, R. P., & Kushwaha, O. S. (2013). Polymer Solar Cells: An Overview. Macromolecular
Symposia, 327(1), 128–149.
Sinha Ray, S. (2013). Environmentally friendly polymer nanocomposites: types, processing and
properties.
Song, K., Wu, Q., Zhang, Z., Ren, S., Lei, T., Negulescu, I. I., & Zhang, Q. (2015). Porous Carbon
Nanofibers from Electrospun Biomass Tar/Polyacrylonitrile/Silver Hybrids as Antimicrobial
Materials. ACS Applied Materials & Interfaces, 7(27), 15108–16.
Sumesh, E., Bootharaju, M. S., & Pradeep, T. (2011). A practical silver nanoparticle-based adsorbent
for the removal of Hg 2+ from water. Journal of Hazardous Materials, 189(1), 450–457.
Sureshkumar, M., Siswanto, D. Y., & Lee, C.-K. (2010). Magnetic antimicrobial nanocomposite
based on bacterial cellulose and silver nanoparticles. Journal of Materials Chemistry, 20(33),
6948–6955.
Wang, F., Guo, C., Yang, L., & Liu, C.-Z. (2010). Magnetic mesoporous silica nanoparticles:
fabrication and their laccase immobilization performance. Bioresource Technology, 101(23),
8931–8935.
Xu, Q., Chen, C., Rosswurm, K., Yao, T., & Janaswamy, S. (2016). A facile route to prepare
cellulose-based films. Carbohydrate Polymers, 149, 274–281.
Yan, L., & Gao, Z. (2008). Dissolving of cellulose in PEG/NaOH aqueous solution.
Cellulose, 15(6), 789–796.
Zhang, F., Zhao, Y., Sun, L., Ding, L., Gu, Y., & Gong, P. (2011). Synthesis and anti-tumor activity
of 2-amino-3-cyano-6-(1H-indol-3-yl)-4-phenylpyridine derivatives in vitro. European Journal
of Medicinal Chemistry, 46(7), 3149–3157.
Zhang, X., Liu, X., Zheng, W., & Zhu, J. (2012). Regenerated cellulose/graphene nanocomposite
films prepared in DMAC/LiCl solution. Carbohydrate Polymers, 88(1), 26–30.
Zhou, J. F., Gong, G. X., & Zhu, F. X. (2009). Microwave promoted one-pot synthesis of 3-(2′-
amino-3′-cyano-4′-arylpyrid-6′-yl) coumarins. Chinese Chemical Letters, 20(1), 37–39.
Figure captions

Fig. 1 a, b) FE-SEM images of the magnetic cellulose/Ag nanobiocomposite in different
magnifications, c) FE-SEM image of the magnetic cellulose, d) the particle size distribution diagram
of the magnetic cellulose/Ag nanobiocomposite.
Fig. 2 a) XRD pattern of the magnetic cellulose/Ag nanobiocomposite, b) JCPDS of Ag, c) JCPDS of
γ-Fe2O3.
Fig. 3 a) EDX analysis of the magnetic cellulose/Ag nanobiocomposite, (b–f) SEM–EDX mapping:
(b) SEM image and (c–f) the corresponding EDX mapping of Fe, Ag, O and C, respectively.
Fig. 4 a) The magnetic properties of the magnetic cellulose/Ag nanobiocomposite, b) The
recyclability study of the nanocatalyst.
Fig. 5 a) TGA and b) DTA curves of the magnetic cellulose/Ag nanobiocomposite.
Scheme 1 Preparation of: i) 3-acetylcoumarin 3, ii) 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-
phenylnicotinonitrile 7a-l.
Scheme 2 Proposed mechanism for the synthesis of i) 3-acethylcumarine 3 and ii) substituted 2-
amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitriles 7 by using the magnetic cellulose/Ag
nanobiocomposite.
Tables
Table 1 Optimization of the nanocatalyst amount and the reaction conditions in the synthesis of 2-
amino-6-(2-oxo-2H-chromen-3-yl)-4-(3-nitrophenyl)nicotinonitrile 7b as the model reaction.
Yielda
Amount of
catalyst (g)
Temperature
(ºC)
Entry
Catalyst
Solvent
Time (h)
(%)
-
Magnetic
cellulose/Ag
1
2
3
4
-
Ethanol
Ethanol
Ethanol
Ethanol
60
60
60
60
3
3
Magnetic
cellulose/Ag
0.05
0.1
54
75
89
Magnetic
cellulose/Ag
2
Magnetic
cellulose/Ag
0.15
1.5
Magnetic
cellulose/Ag
5
6
0.2
Ethanol
Ethanol
60
60
1.5
1.5
89
32
0.15
Magnetic

cellulose
Cellulose/Ag
Cellulose
7
8
0.15
0.15
Ethanol
Ethanol
60
60
1.5
3
65
Trace
Magnetic
cellulose/Ag
9
0.15
0.15
0.15
0.15
0.15
Ethanol
Ethanol
r.t.
reflux
60
3
35
89
-
Magnetic
cellulose/Ag
10
11
12
13
1.5
1.5
1.5
1.5
Magnetic
cellulose/Ag
Water
Magnetic
cellulose/Ag
Acetonitrile
Dichloromethane
60
25
-
Magnetic
cellulose/Ag
39
Table 2 Synthesis of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-phenylnicotinonitrile derivatives by
using the magnetic cellulose/Ag nanocatalyst.
M.P. (o C)
Literature
Time
(h)
Yielda
(%)
Entry
1
Aldehyde 4
Product
Observed
256-257
258-259 (Banothu,
Bavantula, & Crooks, 2013)
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1.5
84
7a
262-264(Banothu et al.,
2013)
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1.5
262-264
250-252
2
3
89b
7b
7c
252–254(Zhou, Gong, &
Zhu, 2009)
1.5
87

303-305(Banothu et al.,
2013)
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1.5
1.5
2
91
90
85
87
80
88
84
81
305-308
228-230
293-294
332-334
258-260
271-273
262-264
242-244
4
5
7d
7e
7f
224-226 (Ghashang et al.,
2013)
287-289(Banothu et al.,
2013)
6
1.5
2.5
1.5
2
-
7
7g
7h
7i
263-264 (Zhou et al., 2009)
271-273 (Zhou et al., 2009)
268-270 (Zhou et al., 2009)
8
9
10
11
7j
238-240 (Ghashang et al.,
2013)
2
7k

232-234 (Ghashang et al.,
2013)
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2
90
232-234
12
7l
a Isolated yield.
b Yields of the five subsequent runs by using the same recovered catalyst were 87, 86, 83, 81,
and 78%, respectively.