Magnetite tethered mesoionic carbene-palladium (II): An efficient and reusable nanomagnetic catalyst for Suzuki-Miyaura and Mizoroki-Heck cross-coupling reactions in aqueous medium

Article abstract of DOI:10.1002/aoc.4846

In this paper, a highly active, air- and moisture-stable and easily recoverable magnetic nanoparticles tethered mesoionic carbene palladium (II) complex (MNPs-MIC-Pd) as nanomagnetic catalyst was successfully synthesized by a simplistic multistep synthesis under aerobic conditions using commercially available inexpensive chemicals for the first time. The synthesized MNPs-MIC-Pd nanomagnetic catalyst was in-depth characterized by numerous physicochemical techniques such as FT-IR, ICP-AES, FESEM, EDS, TEM, p-XRD, XPS, TGA and BET surface area analysis. The prepared MNPs-MIC-Pd nanomagnetic catalyst was used to catalyze the Suzuki–Miyaura and Mizoroki–Heck cross-coupling reactions and exhibited excellent catalytic activity for various substrates under mild reaction conditions. Moreover, MNPs-MIC-Pd nanomagnetic catalyst could be easily and rapidly recovered by applying an external magnet. The recovered MNPs-MIC-Pd nanomagnetic catalyst exhibited very good catalytic activity up to ten times in Suzuki–Miyaura and five times in Mizoroki–Heck cross-coupling reactions without considerable loss of its catalytic activity. However, MNPs-MIC-Pd nanomagnetic catalyst shows notable advantages such as heterogeneous nature, efficient catalytic activity, mild reaction conditions, easy magnetic work up and recyclability.

Full text of DOI:10.1002/aoc.4846

Received: 12 October 2018
DOI: 10.1002/aoc.4846
Revised: 9 January 2019
Accepted: 9 January 2019
F U L L P A P E R
Magnetite tethered mesoionic carbene‐palladium (II): An
efficient and reusable nanomagnetic catalyst for Suzuki‐
Miyaura and Mizoroki‐Heck cross‐coupling reactions in
aqueous medium
Manjunatha Kempasiddhaiah1 | Vishal Kandathil1 | Ramesh B. Dateer1 | Balappa S. Sasidhar2 |
Shivaputra A. Patil3 | Siddappa A. Patil1
1 Centre for Nano and Material Sciences,
In this paper, a highly active, air‐ and moisture‐stable and easily recoverable
Jain University, Jain Global Campus,
Kanakapura, Ramanagaram, Bangalore
magnetic nanoparticles tethered mesoionic carbene palladium (II) complex
562112, India
2 Organic Chemistry Section, Chemical
(MNPs‐MIC‐Pd) as nanomagnetic catalyst was successfully synthesized by a
simplistic multistep synthesis under aerobic conditions using commercially
Sciences & Technology Division, National
Institute for Interdisciplinary Science and
Technology (CSIR), Thiruvananthapuram
695019, Kerala, India
3 Pharmaceutical Sciences Department,
College of Pharmacy, Rosalind Franklin
University of Medicine and Science, 3333
Green Bay Road, North Chicago, IL 60064,
USA
available inexpensive chemicals for the first time. The synthesized MNPs‐
MIC‐Pd nanomagnetic catalyst was in‐depth characterized by numerous phys-
icochemical techniques such as FT‐IR, ICP‐AES, FESEM, EDS, TEM, p‐XRD,
XPS, TGA and BET surface area analysis. The prepared MNPs‐MIC‐Pd
nanomagnetic catalyst was used to catalyze the Suzuki–Miyaura and
Mizoroki–Heck cross‐coupling reactions and exhibited excellent catalytic activ-
ity for various substrates under mild reaction conditions. Moreover, MNPs‐
MIC‐Pd nanomagnetic catalyst could be easily and rapidly recovered by apply-
ing an external magnet. The recovered MNPs‐MIC‐Pd nanomagnetic catalyst
exhibited very good catalytic activity up to ten times in Suzuki–Miyaura and
five times in Mizoroki–Heck cross‐coupling reactions without considerable loss
of its catalytic activity. However, MNPs‐MIC‐Pd nanomagnetic catalyst shows
notable advantages such as heterogeneous nature, efficient catalytic activity,
mild reaction conditions, easy magnetic work up and recyclability.
Correspondence
Siddappa A. Patil, Centre for Nano and
Material Sciences, Jain University, Jain
Global Campus, Kanakapura,
Ramanagaram, Bangalore 562112, India.
Email: p.siddappa@jainuniversity.ac.in;
patilsiddappa@gmail.com
Funding information
Jain University; DST‐Nanomission, India,
Grant/Award Number: SR/NM/NS‐20/
2014; DST‐SERB, India, Grant/Award
Number: YSS/2015/000010
KEYWORDS
magnetic nanoparticles, mesoionic carbene‐palladium (II), Mizoroki‐heck cross‐coupling,
nanomagnetic catalyst, Suzuki‐Miyaura cross‐coupling
1 | INTRODUCTION
and could be reused.[1] In general, catalysts can be
broadly classified into two types, homogeneous and het-
A catalyst is a chemical substance that can increase the
rate of chemical reaction through altering the activation
energy which is essential for the chemical reaction to pro-
ceed. Unlike the other reagents, catalyst take part in the
chemical reaction but is chemically not used up and
remains unchanged at the end of the chemical reaction
erogeneous depending on the physical state of the catalyst
and reactants in the chemical reaction. In homogeneous
catalysis, catalyst and all the reactants are in the same
phase usually in the liquid phase while in heterogeneous
catalysis, catalysts are solid compounds that are mixed
with liquid or gas phase reactants.[2,3] Homogeneous
Appl Organometal Chem. 2019;e4846.
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© 2019 John Wiley & Sons, Ltd.
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https://doi.org/10.1002/aoc.4846

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KEMPASIDDHAIAH ET AL.
and heterogeneous catalysts both have advantages and
disadvantages. An advantage of homogeneous catalysts
is that the catalyst combines well with reaction mixture
permitting high degree of association between catalyst
and reactants and increases the efficiency of the reaction.
However, it is hard to separate homogeneous catalyst
from the product and lowers its recovery at the end of
the chemical reaction.[4] On the other hand, the utmost
advantage of heterogeneous catalyst is the effortlessness
of separation of the catalyst from the reaction mass and
the disadvantage being their limited activity and selectiv-
ity.[5] Hence, there is an urgent need for a catalyst which
can increase the efficiency of the chemical reaction like
homogenous catalyst and can be isolated easily after reac-
tion completion similar to heterogeneous catalyst.
First free and stable N‐heterocyclic carbene (NHC) was
isolated by Arduengo and co‐workers in 1991 through
deprotonation of 1,3‐bisadamantyl imidazolium chlo-
ride.[6] After that, N‐heterocyclic carbenes (NHCs) have
emerged as potent ligand precursors in organometallic
chemistry and catalysis. However, since last two decades
NHCs have demonstrated significant input over phos-
phines because of their stability in air‐ and moisture, less
toxicity, higher dissociation energies and strong σ‐donor
properties which enhances the stability of the resulting
metal complexes.[7–17] In general NHCs can be classified
into two categories: classic NHCs and mesoionic carbenes
(MICs). NHCs resulting from imidazol‐2‐ylidenes and
1,2,4‐triazol‐5‐ylidenes belong to the class of classic NHCs.
NHCs derived from 1,2,4‐ and 1,3,4‐trisubstituted 1,2,3‐
triazol‐5‐ylidenes and imidazol‐4‐ylidenes belong to the
class of MICs.[18] Recent past, 1,3,4‐trisubstituted 1,2,3‐
triazol‐5‐ylidenes (MICs) and their corresponding metal
complexes have drawn a lot of attention in homogeneous
catalysis of various organic reactions such as carbon–
carbon (C–C) and carbon–nitrogen (C–N) cross‐coupling
reactions.[19] This development may be endorsed from
the stronger σ‐donor ability of the carbene carbon of
1,3,4‐trisubstituted 1,2,3‐triazol‐5‐ylidene than that of
classical NHC.[20–22]
disadvantages of homogeneous catalysts include difficulty
of their recovery from the reaction medium for reuse. This
problem is of economic and environmental concern in
bulk synthesis. To conquer these difficulties, nowadays,
magnetic nanoparticles have been used as a catalyst sup-
port, which include the advantage of very high surface area
and easy recovery and recycling of catalyst. In this way,
magnetic separation offers a convenient and efficient
method for the recovery of the nanomagnetic catalyst from
C–C cross‐coupling reaction systems.[37]
Extensive literature survey reveals that no reports are
available on the synthesis and characterization of 1,3,4‐
trisubstituted 1,2,3‐triazol‐5‐ylidene metal complexes on
the surface of magnetic nanoparticles with high catalytic
activity in Suzuki–Miyaura and Mizoroki‐Heck cross‐
coupling reactions. Thus in continuation of our investiga-
tions on magnetically recyclable nanomagnetic catalysts
in various organic transformations, we report here a
new magnetic nanoparticle supported 1,3,4‐trisubstituted
1,2,3‐triazol‐5‐ylidene‐palladium (II) nanomagnetic cata-
lyst whose ligand system is based on mesoionic carbenes
which is entirely different from NHCs and Schiff‐base
ligand system which were reported in our earlier
work.[38–41] The MNPs‐MIC‐Pd nanomagnetic catalyst
was structurally characterized from spectroscopic and
microscopic techniques. In addition, The MNPs‐MIC‐Pd
nanomagnetic catalyst exhibited very good catalytic
activity in both Suzuki–Miyaura and Mizoroki‐Heck
cross‐coupling reactions. Furthermore, MNPs‐MIC‐Pd
nanomagnetic catalyst can be easily recovered from the
reaction mixture by using an external magnet and reused
up to ten times in Suzuki–Miyaura and five times in
Mizoroki‐Heck cross‐coupling reactions without much
loss in the catalytic activity. The use of environmentally‐
friendly solvent system Ethanol:water (EtOH:H2O) (1:1)
and recyclable MNPs‐MIC‐Pd nanomagnetic catalyst at
room temperature makes our reaction protocol more
interesting for both Suzuki–Miyaura and Mizoroki‐Heck
cross‐coupling reactions. Therefore, our research
endeavors have recognized the atom‐economy and ideal
greener conditions to accomplish an excellent yield for
both Suzuki–Miyaura and Mizoroki‐Heck cross‐coupling
reactions. We wish our research results will add great
value to the environmentally sustainable and green
chemistry research field.
The Suzuki–Miyaura and Mizoroki‐Heck cross‐
coupling reactions are some of the widely used C‐C bond
forming reactions in organic transformations. These
chemical reactions have been applied to the synthesis
of complex natural products, engineering materials such
as conducting polymers, molecular wires, supramolecu-
lar chemistry, liquid crystals and functionalized ole-
fins.[23–32] Therefore, various types of catalysts have been
developed for Suzuki–Miyaura and Mizoroki‐Heck cross‐
coupling reactions. Among these, 1,3,4‐trisubstituted
1,2,3‐triazol‐5‐ylidene metal complexes have shown tre-
mendous catalytic activities and various homogeneous cat-
alysts have been developed.[19,33–36] However, the major
2 | EXPERIMENTAL
2.1 | Materials
Required solvents were purified according to the standard
methods prior to use. Unless otherwise stated, all reactions
were performed under aerobic or nitrogen atmosphere

KEMPASIDDHAIAH ET AL.
3 of 22
conditions in oven‐dried glassware with magnetic stirrer.
All chemicals were purchased from Sigma‐Aldrich and
Avra chemical companies and were used without further
purification. Heating was accomplished by either a heating
mantle or silicone oil bath. Column chromatography was
conducted on Silica gel 60–120 mesh (Merck) and prepar-
ative thin‐layer chromatography was carried out using
0.25 mm Merck TLC silica gel plates using UV light as a
visualizing agent. Yields refer to chromatographically pure
material. Concentration in vacuo refers to the removal of
volatile solvent using a rotary evaporator attached to a
dry diaphragm pump (10–15 mm Hg) followed by
pumping to a constant weight with an oil pump (<300
mTorr). All the organic products were known and identi-
fied by comparison of their physical and spectral data with
those of authentic samples.
vigorously stirred for 30 min at 85 °C. Subsequently 25%
ammonia solution was added drop wise (up to pH = 10)
and stirring was continued for 30 min at 85 °C. Then
reaction mixture was cooled to room temperature and
obtained black colored MNPs were separated by an exter-
nal magnet. MNPs were washed thoroughly with distilled
water up to neutral pH and further washed with ethanol
(2 x 20 ml) and dried over night at 80 °C.
2.4 | Synthesis of 3‐(azidopropyl)
triethoxysilane (APTES) (3)
3‐Chloropropyltriethoxysilane (2) (1.0 g, 4.15 mmol) was
taken in two necked round bottom flask (100 ml) and
sodium azide (0.40 g, 6.15 mmol) was added. The reaction
mixture was refluxed for 48 hr in acetonitrile (CH3CN)
(40 mL) under nitrogen atmosphere in the presence of
tetrabutylammonium iodide (0.076 g, 0.20 mmol). Solvent
was removed under reduced pressure and crude product
obtained was dissolved with diethyl ether (20 ml)
followed by hyflo filtration and removal of diethyl ether
in vacuo to get pure 3‐(azidopropyl)triethoxysilane
(APTES) (3) as colorless liquid. 1H NMR (400 MHz,
CDCl3): δ (ppm) = 3.76–3.81 (m, 6H), 3.48–3.51 (t,
J = 6 Hz, 2H), 1.81–1.88 (m, 2H), 1.17–1.21 (t, J = 8 Hz,
9H), 0.69–0.73 (t, J = 8 Hz, 2H). 13C NMR (100 MHz,
CDCl3): δ (ppm) = 58.57, 53.86, 18.21, 7.95, 7.38.
2.2 | Instrumentation and analyses
Fourier‐Transform infrared spectra were recorded with
PerkinElmer spectrometer. Brunauer–Emmett–Teller sur-
face areas were obtained by physisorption of nitrogen
using Microtrac BELSORP MAX instrument. FESEM
images along with energy dispersive X‐ray spectroscopy
to observe morphology and elemental distributions respec-
tively were obtained with JEOL Model‐JSM7100F. Trans-
mission electron microscope images were obtained using
Jeol/JEM 2100 microscope. X‐ray powder diffractometer
patterns were obtained using Ultima IV X‐Ray Diffractom-
eter. X‐ray photoelectron spectroscopy was obtained using
PHI 5000 Versa probe‐ Scanning ESCA MicroProbe.
Thermogravimetric analysis was carried out by Thermal
analyzer (TGA/DTA) (STA‐2500, NETZSCH, Berlin,
Germany) with a heating rate of 10.0 °C/min. The
palladium content of the MNPs‐MIC‐Pd nanomagnetic
catalyst was determined by Perkin Elmer inductively
coupled plasma‐atomic emission spectroscopy. 1H and
13C NMR spectra were recorded at 400 MHz, and are
reported relative to deuterated chloroform (CDCl3,
δ = 7.27 ppm). 1H NMR coupling constants (J) are reported
in Hertz (Hz) and multiplicities are indicated as follows: s
(singlet), d (doublet), t (triplet), m (multiplet).
2.5 | Synthesis of magnetic nanoparticles
tagged silyl azide (MNPsSA) (4)
Hydroxyl substituted magnetic nanoparticles (1) (3.0 g)
were taken in toluene (60 ml) and sonicated for 1 hr.
Then APTES (3) (1.2 g, 4.85 mmol) was added drop wise
and resultant reaction mixture was heated at 110 °C for
24 hr under nitrogen atmosphere. The reaction mixture
was cooled to room temperature after required time.
Obtained brown colored azide functionalized magnetic
nanoparticles were collected by using an external magnet,
washed with toluene (2 x 20 ml) and acetone (2 x 20 ml)
and dried overnight at 45 °C to obtain pure magnetic
nanoparticles tagged silyl azide (MNPsSA) (4).
2.3 | Synthesis of hydroxyl substituted
magnetic nanoparticles (MNPs) (1)
2.6 | Synthesis of magnetic nanoparticles
attached 1,2,3‐triazole (MNPsT) (6)
Hydroxyl substituted magnetic nanoparticles (MNPs) (1)
were synthesized using 2:1 molar ratio of FeCl3·6H2O
(4.70 g, 17.38 mmol) and FeCl2·4H2O (1.73 g, 8.70 mmol)
by chemical co‐precipitation method. A mixture of
FeCl3·6H2O and FeCl2·4H2O was dispersed in deionized
water (80 ml) and the resultant yellow solution was
Phenyl acetylene (5) (1.5 g, 14.68 mmol) was added to a
stirring mixture of MNPsSA (3.0 g) and copper iodide
(0.56 g, 2.9 mmol) in dimethylformamide:tetrahydrofuran
(DMF:THF) (1:1) (40 ml) solvent mixture at room tem-
perature in the presence of triethylamine (5.94 g,

4 of 22
KEMPASIDDHAIAH ET AL.
41.84 mmol). The stirring of reaction mixture was contin-
ued for three days at room temperature under nitrogen
atmosphere. Obtained brown colored magnetic nanopar-
ticles attached 1,2,3‐triazole (MNPsT) was separated by
an external magnet and washed with diethyl ether (3 x
20 ml), acetone (2 x 20 ml) and 10% ammonia solution
(2 x 20 ml) and dried overnight at 45 °C to get pure mag-
netic nanoparticles attached 1,2,3‐triazole (6).
coupled product was purified by column chromatography
to afford the corresponding products in good yields. All
the cross‐coupled products were known molecules and
were confirmed by comparing the melting point and H
NMR spectroscopic data with authentic samples.
1
1. Biphenyl (Table 3, entries 1, 2 and 3): Colorless crys-
1
tals. Melting point = 67–70 °C; H NMR (400 MHz,
CDCl3): δ (ppm) = 7.74–7.72 (m, 4H), 7.55–7.53 (m,
4H), 7.46 (t, J = 6.0 Hz, 2H).
2.7 | Synthesis of magnetic nanoparticles
tethered 1,2,3‐triazolium salt (MNPsTS) (7)
2. 4‐Methoxybiphenyl (Table 3, entries 4 and 5): White
powder. Melting point = 86–90 °C; 1H NMR
(400 MHz, CDCl3): δ (ppm) = 7.56–7.52 (m, 4H),
7.43 (t, J = 6.0 Hz, 2H), 7.31 (t, J = 6.0 Hz, 1H),
6.98 (d, J = 4.0 Hz, 2H), 3.84 (s, 3H).
Magnetic nanoparticles attached 1,2,3‐triazole (6) (3.0 g)
was dispersed in CH3CN (50 ml) and sonicated for
10 min. Then methyl iodide (5.63 g, 39.66 mmol) was
added drop wise to the reaction mixture and refluxed
for 2 days under nitrogen atmosphere. Obtained solid
was separated from the reaction mixture using an exter-
nal magnet and washed with ether (3 x 20 ml) and dried
overnight at 45 °C to get magnetic nanoparticles tethered
1,2,3‐triazolium salt (MNPsTS) (7).
3. 2‐Methoxybiphenyl (Table 3, entry 6): White powder.
Melting point = 30–32 °C; 1H NMR (400 MHz,
CDCl3): δ (ppm) = 7.53 (d, J = 4.0 Hz, 2H), 7.42 (t,
J = 8.0 Hz, 2H), 7.33 (t, J = 6.0 Hz, 3H), 7.04 (t,
J = 6.0 Hz, 1H), 6.99 (d, J = 8.0 Hz, 1H), 3.80 (s, 3H).
4. 4‐Methylbiphenyl (Table 3, entry 7 and 8): White
crystalline solid. Melting point = 45–47 °C; 1H
NMR (400 MHz, CDCl3): δ (ppm) = 7.59 (d,
J = 8.0 Hz, 2H), 7.51(d, J = 8.0 Hz, 2H), 7.44 (t,
J = 6.0 Hz, 3H), 7.34 (t, J = 6.0 Hz, 2H), 2.40 (s, 3H).
5. 2‐Methylbiphenyl (Table 3, entry 9): Colorless liquid;
1H NMR (400 MHz, CDCl3): δ (ppm) = 7.90 (d,
J = 8.0 Hz, 2H), 7.70 (d, J = 4.0 Hz, 2H), 7.58 (d,
J = 4.0 Hz, 2H), 7.43 (t, J = 6.0 Hz, 2H), 7.37 (t,
J = 6.0 Hz, 1H), 1.38 (s, 3H).
6. 2‐Phenylbenzaldehyde (Table 3, entry 10): Yellow oil.
1H NMR (400 MHz, CDCl3): δ (ppm) = 9.99 (s, 1H),
8.04 (d, J = 8.0 Hz, 1H), 7.73 (t, J = 4.0 Hz, 2H),
7.66 (t, J = 6.0 Hz, 1H), 7.49–7.45 (m, 3H), 7.39 (d,
J = 4.0 Hz, 2H).
7. 4‐Phenylbenzaldehyde (Table 3, entry 11): Yellow
crystals. Melting point = 57–59 °C; 1H NMR
(400 MHz, CDCl3): δ (ppm) = 10.06 (s, 1H), 7.96 (d,
J = 4.0 Hz, 2H), 7.77(d, J = 8.0 Hz, 2H), 7.65 (d,
J = 8.0 Hz, 2H), 7.50 (t, J = 6.0 Hz, 2H), 7.43(t,
J = 6.0 Hz, 1H).
2.8 | Synthesis of magnetic nanoparticles
supported mesoionic carbene‐palladium
(II) complex (MNPs‐MIC‐Pd) (8)
Palladium (II) acetate (0.616 g, 2.74 mmol) was added to
the reaction mixture of magnetic nanoparticles attached
1,2,3‐triazolium salt (2.8 g) and sodium carbonate
(0.247 g, 2.33 mmol) in acetonitrile (CH3CN) (50 mL).
The reaction mixture was heated at 70 °C for 16 hr.
Obtained brown colored solid was separated by an exter-
nal magnet and washed with CH3CN (2 x 20 mL) and
acetone (2 x 20 ml) and dried over night at 45 °C to obtain
pure magnetic nanoparticles supported mesoionic
carbene‐palladium (II) complex (MNPs‐MIC‐Pd) (8).
2.9 | General procedure for Suzuki–
Miyaura cross‐coupling reaction
A mixture of aryl halide (1.0 mmol), arylboronic acid
(1.1 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst
(0.025 mol% Pd respected to aryl halide) and base
(2.2 mmol) was stirred in EtOH:H2O (1:1) system
(10 ml) at room temperature and the reaction progress
was monitored by thin layer chromatography. After com-
pletion of the reaction, the MNPs‐MIC‐Pd nanomagnetic
catalyst was separated by applying an external magnet
followed by addition of dichloromethane (DCM) (2 x
20 ml). The organic layer was washed with water (3 x
10 ml), dried over anhydrous MgSO4 and the solvent
was evaporated under reduced pressure. Then cross‐
8. 4‐Acetylbiphenyl (Table 3, entry 12): White powder.
1
Melting point = 120–123 °C; H NMR (400 MHz,
CDCl3): δ (ppm) = 8.03 (d, J = 4.0 Hz, 2H), 7.69
(d, J = 8.0 Hz, 2H), 7.63 (d, J = 8.0 Hz, 2H), 7.48
(t, J = 6.0 Hz, 2H), 7.41 (t, J = 6.0 Hz, 1H), 2.63
(s, 3H).
9. 4‐Hydroxybiphenyl (Table 3, entries 13 and 14):
White crystals. Melting point = 164–166 °C; 1H
NMR (400 MHz, CDCl3): δ (ppm) = 7.54 (d,
J = 4.0 Hz, 2H), 7.48 (d, J = 4.0 Hz, 2H), 7.43 (t,
J = 6.0 Hz, 2H), 7.32 (t, J = 6.0 Hz, 1H), 6.91 (d,
J = 4.0 Hz, 2H), 5.13 (s, 1H).

KEMPASIDDHAIAH ET AL.
5 of 22
10. 1‐Ρhenylnaphthalene (Table 3, entry 15): White solid.
Melting point = 42–45 °C; 1H NMR (400 MHz,
CDCl3): δ (ppm) = 7.91–7.85 (m, 3H), 7.54–7.47 (m,
6H), 7.44 (t, J = 4.0 Hz, 3H)
2.10 | General procedure for Mizoroki–
Heck cross‐coupling reaction
Aryl halide (1.0 mmol), alkene (1.2 mmol), MNPs‐MIC‐
Pd nanomagnetic catalyst (0.05 mol% of Pd respected to
aryl halide) and base (2.0 mmol) were taken in EtOH:
H2O (1:1) (10 ml). Then reaction mixture was stirred at
room temperature for required time and progress of reac-
tion was monitored by thin layer chromatography. After
reaction, MNPs‐MIC‐Pd nanomagnetic catalyst was sepa-
rated by an external magnet. The reaction mixture was
diluted with water and the resultant mixture was
extracted with dichloromethane (20 ml) to isolate the
product, dried over anhydrous MgSO4, filtered off and
evaporated under reduced pressure. The crude products
were purified by column chromatography to afford the
corresponding products in good yields. All the cross‐
coupled products were known molecules and were con-
11. 4‐Cyanobiphenyl (Table 3, entry 16): Off‐white crys-
1
talline powder. Melting point = 85–87 °C; H NMR
(400 MHz, CDCl3): δ (ppm) = 7.74 (d, J = 8.0 Hz,
2H), 7.69 (d, J = 4.0 Hz, 2H), 7.60 (d, J = 8.0 Hz,
2H), 7.50 (t, J = 6.0 Hz 2H), 7.44 (t, J = 6.0 Hz 1H).
12. 4‐(τert‐butyl)‐1,1′‐biphenyl (Table 3, entry 17): Light
1
brown powder, Melting point = 50–52 °C; H NMR
(400 MHz, CDCl3): δ (ppm) = 7.60 (d, J = 8.0 Hz,
2H), 7.55 (d, J = 8.0 Hz, 2H), 7.48 (d, J = 8.0 Hz,
2H), 7.44 (t, J = 6.0 Hz, 2H), 7.34 (t, J = 6.0 Hz, 1H),
1.37 (s, 9H).
13. 2,4‐Difluoro‐1,1′‐biphenyl (Table 3, entry 18): Pale
1
yellow crystals. Melting point = 61–63 °C; H NMR
(400 MHz, CDCl3): δ (ppm) = 7.47 (d, J = 4.0 Hz,
2H), 7.41 (d, J = 4.0 Hz, 2H), 7.36 (t, J = 6.0 Hz,
2H), 7.25 (t, J = 6.0 Hz, 2H), 6.84 (d, J = 4.0 Hz, 1H).
14. 4‐Nitrobiphenyl (Table 3, entry 19): Pale yellow crys-
tals. Melting point = 110–113 °C; 1H NMR
(400 MHz, CDCl3): δ (ppm) = 8.30 (d, J = 8.0 Hz,
2H), 7.74 (d, J = 8.0 Hz, 2H), 7.63 (d, J = 8.0 Hz,
2H), 7.51 (t, J = 6.0 Hz, 2H), 7.46 (t, J = 6.0 Hz, 1H).
15. 4‐Chloro‐1,1′‐biphenyl (Table 3, entries 20): Color-
1
firmed by comparing the melting points and H NMR
spectroscopic data with authentic samples.
1. (E)‐1,2‐diphenylethene (Table 6, entries 1, 2 and 3):
White solid; 1H NMR (400 MHz, CDCl3):
δ
(ppm) = 7.53 (d, J = 8.0 Hz, 4H), 7.38 (t,
J = 6.0 Hz, 4H), 7.28 (t, J = 6.0 Hz, 2H), 7.12 (s, 2H).
2. (E)‐1‐methyl‐4‐styrylbenzene (Table 6, entries 4 and
5): White solid; 1H NMR (400 MHz, CDCl3): δ
(ppm) = 7.51 (d, J = 4.0 Hz, 2H), 7.42 (d,
J = 4.0 Hz, 2H), 7.37 (t, J = 6.0 Hz, 2H), 7.24 (t,
J = 4.0 Hz, 1H), 7.18 (d, J = 8.0 Hz, 2H), 7.08 (d,
J = 4.0 Hz, 2H), 2.36 (s, 3H).
3. (E)‐1‐methoxy‐4‐styrylbenzene (Table 6, entries 6 and
7): White crystalline solid; 1H NMR (400 MHz,
CDCl3): δ (ppm) = 7.50–7.45 (m, 4H), 7.36 (t,
J = 6.0 Hz, 2H), 7.25 (t, J = 6.0 Hz, 1H), 7.06 (d,
J = 28 Hz, 2H), 6.91 (d, J = 8.0 Hz, 2H), 3.83 (s, 3H).
4. (E)‐4‐styrylbenzonitrile (Table 6, entry 9): Yellow solid;
1H NMR (400 MHz, CDCl3): δ (ppm) = 7.74–7.72 (m,
2H), 7.61 (d, J = 8.0 Hz, 1H), 7.55–7.52 (m, 2H), 7.30
(d, J = 4.0 Hz, 2H), 7.08–7.06 (m, 2H), 6.61 (d,
J = 8.0 Hz, 2H).
1
less crystals. Melting point = 76–78 °C; H NMR
(400 MHz, CDCl3): δ (ppm) = 7.55–7.50 (m, 4H),
7.45–7.33 (m, 5H)
16. 4‐Chloro‐4′‐methoxy‐1,1′‐biphenyl (Table 3, entry
21): White solid. Melting point = 91–93 °C; 1H
NMR (400 MHz, CDCl3): δ (ppm) = 7.49–7.45 (m,
4H), 7.38 (d, J = 8.0 Hz, 2H), 6.98 (d, J = 8.0 Hz,
2H), 3.84 (s, 3H).
17. 17.4′‐Chloro‐[1,1′‐biphenyl]‐4‐carbonitrile (Table 3,
entry 22): White solid. Melting point = 133–
135 °C; 1H NMR (400 MHz, CDCl3): δ (ppm) = 7.73
(d, J = 8.0 Hz, 2H), 7.65 (d, J = 8.0 Hz, 2H), 7.52 (d,
J = 8.0 Hz, 2H), 7.45 (d, J = 8.0 Hz, 2H).
18. [1,1′‐Biphenyl]‐4‐carboxylic acid (Table 3, entry 23):
1
White solid. Melting point = 220–225 °C; H NMR
5. Tert‐butyl cinnamate (Table 6, entries 11, 12 and 13):
Off‐white solid; 1H NMR (400 MHz, CDCl3): δ
(ppm) = 7.53 (d, J = 12 Hz, 1H), 7.45–7.43 (m, 2H),
7.31–7.29 (m, 3H), 6.32 (d, J = 12 Hz, 1H), 1.35 (s, 9H).
6. (E)‐tert‐butyl 3‐(p‐tolyl)acrylate (Table 6, entries 14
and 15): Light yellow liquid; 1H NMR (400 MHz,
CDCl3): δ (ppm) = 7.58 (d, J = 16 Hz, 1H), 7.41 (d,
J = 4.0 Hz, 2H), 7.18 (d, J = 4.0 Hz, 2H), 6.34 (d,
J = 12 Hz, 1H), 2.37(s, 3H), 1.53 (s, 9H).
(400 MHz, CDCl3): δ (ppm) = 12.39 (s, 1H), 7.76–
7.74 (m, 4H), 6.79–6.75 (m, 5H).
19. 4′‐Methoxy‐[1,1′‐biphenyl]‐4‐carboxylic acid (Table 3,
entry 24): White solid. Melting point = 251–254 °C;
1H NMR (400 MHz, CDCl3): δ (ppm) = 12.57 (s,
1H), 7.96 (d, J = 8.0 Hz, 2H), 7.67 (d, J = 8.0 Hz,
2H), 7.03 (d, J = 8.0 Hz, 2H). 6.79 (d, J = 8.0 Hz,
2H), 3.78 (s, 3H).
20. 4′‐Cyano‐[1,1′‐biphenyl]‐4‐carboxylic acid (Table 3,
entry 25): Colorless crystals. Melting point = 261–
263 °C; 1H NMR (400 MHz, CDCl3): δ (ppm) = 12.43
(s, 1H), 7.76 (m, 4H), 6.79 (m, 4H).
7. (E)‐tert‐butyl 3‐(4‐cyanophenyl)acrylate (Table 6, entry
16): Colorless crystals; 1H NMR (400 MHz, CDCl3): δ
(ppm) = 7.74–7.72 (m, 1H), 7.61 (d, J = 8.0 Hz, 1H),

6 of 22
KEMPASIDDHAIAH ET AL.
7.55–7.52 (m, 2H), 7.30 (d, J = 4.0 Hz, 1H), 6.61 (d,
J = 4.0 Hz, 1H), 1.42 (s, 9H).
3 | RESULTS AND DISCUSSION
3.1 | Synthesis of MNPs‐MIC‐Pd
nanomagnetic catalyst
2.11 | Recovery of the MNPs‐MIC‐Pd
nanomagnetic catalyst
Continuing our work on functionalizing magnetic
nanoparticles with variety of derivatives for catalytic
applications,[38–42] in the research accounted here we
determined to demonstrate the synthesis of magnetic
nanoparticles by attaching mesoionic carbene‐palladium
(II) complex on the surface of hydroxyl substituted mag-
netic nanoparticles for the first time. The MNPs‐MIC‐Pd
nanomagnetic catalyst was prepared following the proce-
dure shown in Scheme 1. Firstly, hydroxyl substituted
magnetic nanoparticles (1) were synthesized by using
After the completion of reaction, MNPs‐MIC‐Pd
nanomagnetic catalyst was separated from reaction mix-
ture using an external magnet. The MNPs‐MIC‐Pd
nanomagnetic catalyst was then washed thoroughly with
water (2 x 10 ml), followed by ethanol (2 x 10 ml). The
separated MNPs‐MIC‐Pd nanomagnetic catalyst was
dried over night at 45 °C. The dried MNPs‐MIC‐Pd
nanomagnetic catalyst could be used for next round of
reaction without further purification.
SCHEME 1 Synthetic route of a) MNPs (1) and b) MNPs‐MIC‐Pd nanomagnetic catalyst (8)

KEMPASIDDHAIAH ET AL.
7 of 22
2:1 molar ratio of FeCl3·6H2O and FeCl2·4H2O in the
presence of ammonia solution by chemical co‐preci-
pitation method. On the other hand, (3‐azidopropyl)
triethoxysilane (3) was synthesized using (3‐chloro-
propyl)triethoxysilane (2) and sodium azide in acetoni-
trile at 85 °C for 48 hr. The magnetic nanoparticles
tagged silyl azide (4) was synthesized by the reaction of
hydroxyl substituted magnetic nanoparticles (1) with (3‐
azidopropyl)triethoxysilane (3) in toluene at 110 °C for
24 hr. Then “click” reaction was employed between mag-
netic nanoparticles tagged silyl azide (4) and phenyl acet-
ylene (5) using copper(I) iodide and triethylamine in a
DMF:THF (1:1) solvent mixture at room temperature for
72 hr to get magnetic nanoparticles attached 1,2,3‐triazole
(6). Subsequently, magnetic nanoparticles tethered 1,2,3‐
triazolium salt (7) was prepared through the reaction of
magnetic nanoparticles attached 1,2,3‐triazole (6) with
methyl iodide in acetonitrile at 85 °C for 48 hr. Lastly,
magnetic nanoparticles tethered 1,2,3‐triazolium salt (7)
was treated with palladium (II) acetate in acetonitrile at
70 °C for 24 hr in the presence of sodium carbonate to
get the desired MNPs‐MIC‐Pd nanomagnetic catalyst (8).
around 598 cm−1 and 3400 cm−1 which are attributed to
the Fe‐O and O‐H stretching vibrations of hydroxyl
substituted magnetic nanoparticles. A medium sharp
peak observed at 2097 cm−1 corresponds to the azide
group of (3‐azidopropyl)triethoxysilane (Figure 1b). The
characteristic peaks of Fe‐O, O‐H, Si‐O and N3 stretching
vibrations observed at 583 cm−1, 3413 cm−1, 1005 cm−1
and 2097 cm−1 respectively confirms the successful for-
mation of magnetic nanoparticles tagged silyl azide
(Figure 1c). Typical bands observed at 1632 cm−1 and
1704 cm−1 corresponds to the aromatic ring stretching
of magnetic nanoparticles attached 1,2,3‐triazole
(Figure 1d). FT‐IR spectrum of magnetic nanoparticles
tethered 1,2,3‐triazolium salt (Figure 1e) reveals the slight
3.2 | Spectroscopic and microscopic
characterization of the MNPs‐MIC‐Pd
nanomagnetic catalyst
3.2.1 | FT‐IR spectroscopy
The chemical structures of products formed in each step
were characterized using FT‐IR spectroscopic technique.
Figure 1 shows FT‐IR spectra of MNPs, APTES, MNPsSA,
MNPsT, MNPsTS and MNPs‐MIC‐Pd nanomagnetic cata-
lyst. Figure 1a demonstrates two characteristic peaks
FIGURE 2 FT‐IR spectra of a) MNPs‐MIC‐Pd nanomagnetic
catalyst, b) Suzuki–Miyaura recycled MNPs‐MIC‐Pd nanomagnetic
catalyst and c) Mizoroki‐Heck recycled MNPs‐MIC‐Pd
nanomagnetic catalyst
FIGURE 1 FT‐IR spectra of a) MNPs,
b) APTES, c) MNPsSA, d) MNPsT, e)
MNPsTS and f) MNPs‐MIC‐Pd
nanomagnetic catalyst

8 of 22
KEMPASIDDHAIAH ET AL.
shifting of aromatic ring stretching from 1632 cm−1 to the
lower wave number 1624 cm−1; this confirms the struc-
ture of magnetic nanoparticles tethered 1,2,3‐triazolium
salt. FT‐IR spectrum of MNPs‐MIC‐Pd nanomagnetic cat-
alyst displays the presence of O‐H and aliphatic C‐H
stretching at 3435 cm−1 and 2922 cm−1 respectively. In
loss can be observed in the range 35 °C to 150 °C that is
due to presence of physically absorbed solvent molecules
as well as hydroxyl groups present on the surface of MNPs.
In the second stage, up to 11% weight loss of the MNPs‐
MIC‐Pd nanomagnetic catalyst can be observed from the
range of 150 °C to 730 °C and this is because of the decom-
position of organic moiety immobilized on surface of
MNPs. Moreover, TGA result confirms the successful
immobilization of organic moiety on the surface of MNPs
and also reveals that MNPs‐MIC‐Pd nanomagnetic cata-
lyst is stable up to 230 °C which helps to carry out the
cross‐coupling reactions even at higher temperature.[38,40]
addition, existence of typical bands at 1622 cm−1
,
1406 cm−1, 1019 cm−1 and 584 cm−1 are attributed to aro-
matic ring stretching, Pd‐C stretching, Si‐O stretching
and Fe‐O stretching vibrations (Figure 1f) respectively
which confirms the successful formation of MNPs‐MIC‐
Pd nanomagnetic catalyst. Figure 2 shows the FT‐IR spec-
tra of MNPs‐MIC‐Pd nanomagnetic catalyst and recycled
MNPs‐MIC‐Pd nanomagnetic catalyst. FT‐IR spectra of
ten times recycled MNPs‐MIC‐Pd nanomagnetic catalyst
from Suzuki‐Miyaura cross‐coupling (Figure 2b) and five
times recycled MNPs‐MIC‐Pd nanomagnetic catalyst
from Mizoroki‐Heck cross‐coupling reactions (Figure 2c)
confirmed that MNPs‐MIC‐Pd nanomagnetic catalyst
was unaltered and remained almost same even after ten
cycles in Suzuki‐Miyaura and five cycles in Mizoroki‐
Heck cross‐coupling reactions.[38,40,43]
3.2.3 | TEM analysis
The morphology and size of MNPs and MNPs‐MIC‐Pd
nanomagnetic catalyst were investigated by transmission
electron microscopy (TEM) (Figure 4). The size of the
hydroxyl substituted magnetic nanoparticles varies from
7–10 nm and they are spherical in nature (Figure 4a).
After anchoring of the MIC‐Pd (II) complex, the size of
the nanoparticles was increased from 10–18 nm with
quasi spherical in nature (Figure 4b). In addition, the
magnetic core as a dark spot inside the spherical MNPs‐
MIC‐Pd nanomagnetic catalyst can be seen from the
TEM image. Moreover, MNPs‐MIC‐Pd nanomagnetic cat-
alyst is polycrystalline in nature which is confirmed by
the selected area electron diffraction pattern shown in
Figure 4c.[38–40,43]
3.2.2 | Thermogravimetric analysis
Thermal stability of MNPs and MNPs‐MIC‐Pd nano-
magnetic catalyst was determined by thermogravimetric
analysis (TGA) under N2 atmosphere at the heating rate
of 10 °C/minute from the range of 35 °C to 730 °C. TGA
graph of MNPs (Figure 3a) shows the weight loss of 3%
due to removal of hydroxyl groups present on the surface
of MNPs. TGA curve of MNPs‐MIC‐Pd nanomagnetic
catalyst (Figure 3b) shows the decomposition of
nanomagnetic catalyst in two stages. Initially 2% weight
3.2.4 | FESEM analysis
FESEM analysis was carried out to get more informa-
tion regarding surface morphologies of fresh MNPs‐
MIC‐Pd nanomagnetic catalyst and recycled MNPs‐
MIC‐Pd nanomagnetic catalyst (Figure 5.) The FESEM
image of fresh MNPs‐MIC‐Pd nanomagnetic catalyst
(Figure 5a) exhibits the formation of uniform nanometer
sized spherical particles. Surprisingly, ten times recycled
MNPs‐MIC‐Pd nanomagnetic catalyst (Figure 5b) from
Suzuki–Miyaura cross‐coupling reaction and five times
recycled
MNPs‐MIC‐Pd
nanomagnetic
catalyst
(Figure 5c) from Mizoroki‐Heck cross‐coupling reaction
demonstrates the same morphology and size.[38–41]
3.2.5 | Elemental analysis
Energy‐dispersive X‐ray spectroscopy (EDS) was employed
to confirm the existence of each element present in the
newly synthesized MNPs‐MIC‐Pd nanomagnetic catalyst.
The EDS spectrum (Figure 6) of the MNPs‐MIC‐Pd
nanomagnetic catalyst exhibits characteristic signals
FIGURE 3 TGA curves of a) MNPs and b) MNPs‐MIC‐Pd
nanomagnetic catalyst

KEMPASIDDHAIAH ET AL.
9 of 22
FIGURE 5 FESEM images of a) MNPs‐MIC‐Pd nanomagnetic
catalyst, b) ten times recycled MNPs‐MIC‐Pd nanomagnetic
catalyst from Suzuki–Miyaura and c) five times recycled MNPs‐
MIC‐Pd nanomagnetic catalyst from Mizoroki‐Heck cross‐coupling
reactions
FIGURE
4
TEM images of a) MNPs, b) MNPs‐MIC‐Pd
nanomagnetic catalyst and c) SAED pattern of MNPs‐MIC‐Pd
nanomagnetic catalyst
corresponding to C, N, O, Si, Fe and Pd atoms which
proves the attachment of MIC‐Pd (II) complex on the sur-
face of the MNPs.[44] Furthermore, elemental mapping
was done to understand the distribution of elements pres-
ent in the MNPs‐MIC‐Pd nanomagnetic catalyst as shown
in Figure 7. The elemental mapping result demonstrates
that all elements are distributed uniformly.[40]
3.2.6 | BET surface area analysis
The surface functionalization of MNPs, MNPsSA and
FIGURE 6 EDS spectrum of the MNPs‐MIC‐Pd nanomagnetic
catalyst
MNPs‐MIC‐Pd nanomagnetic catalyst was investigated

10 of 22
KEMPASIDDHAIAH ET AL.
FIGURE 7 EDS elemental mapping of the MNPs‐MIC‐Pd nanomagnetic catalyst
FIGURE 8 Nitrogen adsorption–
desorption curves for a) MNPs, b)
MNPsSA and c) MNPs‐MIC‐Pd
nanomagnetic catalyst
through Brunauer–Emmett–Teller surface area analysis
(BET). Figure 8a‐8c demonstrate the nitrogen
adsorption–desorption curves for MNPs, MNPsSA and
MNPs‐MIC‐Pd nanomagnetic catalyst respectively. BET
result articulates that the amount of N2 adsorbed on
MNPs‐MIC‐Pd nanomagnetic catalyst is greater than
amount of N2 adsorbed on MNPs. BET graph for MNPs‐
MIC‐Pd nanomagnetic catalyst exhibit the presence of
type‐II isotherm. Moreover, the surface area of MNPs
decreased from 94.51 m2 g−1 to 93.13 m2 g−1 through

KEMPASIDDHAIAH ET AL.
11 of 22
surface functionalization of silyl azide which got further
decreased to 74.42 m2 g−1 after functionalization of MIC‐
Pd (II) complex on the surface of MNPs and thus confirms
the formation of MNPs‐MIC‐Pd nanomagnetic catalyst.[40]
3.2.8 | XRD analysis
X‐ray powder diffraction (XRD) technique was used to
determine the crystalline structure of both MNPs and
MNPs‐MIC‐Pd nanomagnetic catalyst. The X‐ray powder
diffraction pattern for MNPs and MNPs‐MIC‐Pd
nanomagnetic catalyst are shown in Figure 9a and 9b
respectively. XRD pattern for MNPs illustrates the differ-
ent peaks at 2θ of 30.09°, 35.59°, 43.07°, 53.43°, 57.37°
and 62.90° corresponding to the different crystal planes
(220), (311), (400), (422), (511) and (440) respectively.
Moreover, the XRD result confirms the MNPs are exists
in cubic spinel structure. The XRD pattern of MNPs‐
MIC‐Pd nanomagnetic catalyst reveals that there is no
much difference in crystal structure of MNPs‐MIC‐Pd
nanomagnetic catalyst as compared with crystal structure
of MNPs.[38–40]
3.2.7 | ICP‐AES analysis
The exact quantity of palladium loaded on the MNPs‐
MIC‐Pd nanomagnetic catalyst was determined through
inductively coupled plasma‐atomic emission spectroscopy
analysis (ICP‐AES). This analysis demonstrates a loading
of 4.87% (w/w) palladium on the MNPs‐MIC‐Pd
nanomagnetic catalyst.
3.2.9 | XPS analysis
X‐ray photoelectron spectroscopy was carried out to iden-
tify the oxidation state of palladium species present in
MNPs‐MIC‐Pd nanomagnetic catalyst and the obtained
XPS spectra for Pd on MNPs‐MIC‐Pd nanomagnetic cata-
lyst is shown in Figure 10. The palladium XPS spectra
only show the peaks of Pd (II) corresponding to the bind-
ing energy of 343.0 eV (Pd 3d3/2) and 337.8 eV (Pd 3d5/2)
suggesting the existence of palladium (II) and confirming
there is no any metallic palladium(0) present in the
nanomagnetic catalyst which may be formed during the
preparation of the MNPs‐MIC‐Pd nanomagnetic
catalyst.[45,46]
FIGURE 9 XRD patterns of a) MNPs and b) MNPs‐MIC‐Pd
nanomagnetic catalyst
3.3 | Application of the MNPs‐MIC‐Pd
nanomagnetic catalyst in Suzuki–Miyaura
cross‐coupling reactions
In continuation of our studies on the application of transi-
tion metal complexes immobilized on MNPs in organic
transformations, herein we report a simple and efficient
method for the Suzuki–Miyaura cross‐coupling reactions
through coupling of aryl halides with arylboronic acids in
the presence of catalytic amounts of MNPs‐MIC‐Pd
nanomagnetic catalyst. Thus, catalytic activity of newly
synthesized MNP‐MIC‐Pd nanomagnetic catalyst was
established in Suzuki–Miyaura cross‐coupling reactions
using environmentally friendly reaction conditions. The
FIGURE 10 XPS spectra for Pd(3d) core level in MNPs‐MIC‐Pd
nanomagnetic catalyst
SCHEME 2 Suzuki‐Miyaura cross‐
coupling reaction of 4‐bromoanisole with
phenylboronic acid

12 of 22
KEMPASIDDHAIAH ET AL.
reaction conditions were optimized through model
Suzuki–Miyaura cross‐coupling reaction of 4‐bromo-
anisole with phenylboronic acid as shown in Scheme 2.
Currently, across the world many researchers have
shown interest to use green solvents for many organic
transformations to avoid hazardous and toxic solvents
because of environmental concern. Therefore, during
the optimization of reaction conditions, environmentally
benign solvents were given highest priority. Conse-
quently, EtOH and H2O were given highest priority as a
green solvent system. The reaction conditions were
optimized with a series of Suzuki‐Miyaura cross‐coupling
reactions of 4‐bromoanisole with phenylboronic acid in
the presence of MNPs‐MIC‐Pd nanomagnetic as shown in
Table 1. The preliminary results revealed that using
Na2CO3 base and EtOH:H2O (1:1) solvent mixture,
0.025 mol% Pd of MNPs‐MIC‐Pd nanomagnetic catalyst
at room temperature for 10 min resulted in highest yield
(Table 1, entry 3). The catalytic activity of the MNPs‐
MIC‐Pd nanomagnetic catalyst with varying base,
solvent, temperature, time and catalyst ratio was also
studied for the model reaction.
TABLE 1 Optimization of conditions for the model Suzuki–Miyaura cross‐coupling reaction in presence of MNPs‐MIC‐Pd nanomagnetic
catalysta
Entry
Base
Solvent
Temperature (°C)
Time (h)
Yield (%)b
1
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
K2CO3
NaOH
EtOH
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
0
2.0
68
2
H2O
2.0
55
3
EtOH:H2O (1:1)
CH3CN
0.16
3.0
94
4
Trace
58
5
MeOH
2.5
6
THF
3.0
Trace
Trace
Trace
Trace
Trace
92
7
Toluene
2.0
8
DCM
3.0
9
DMF
2.0
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
IPA
1.5
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O(1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
0.16
1.0
84
KOH
1.5
81
Et3N
2.0
85
.
Na3PO4 12H2O
3.0
80
CS2CO3
KF
2.0
78
2.0
Trace
38
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
4.0
15
4.0
52
40
0.16
0.16
0.16
0.16
0.08
0.33
0.5
94
50
94
60
93
70
94
RT
RT
RT
RT
RT
RT
82
94
94
0.66
0.83
1.0
94
94
94
aReaction conditions: 4‐bromoanisole (1.0 mmol), phenylboronic acid (1.1 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.025 mol% Pd with respect to aryl
halide), base (2.2 mmol) and solvent (10 ml) in air.
bIsolated yield after separation by column chromatography.

KEMPASIDDHAIAH ET AL.
13 of 22
depicted in Table 1. High conversion was observed at
room temperature (Table 1, entry 3). At lower reaction
temperatures (0 °C and 15 °C) yield decreases even after
long reaction times (Table 1, entries 18 and 19). At higher
reaction temperatures (40 °C, 50 °C, 60 °C and 70 °C)
yield did not improve (Table 1, entries 20–23). Therefore,
all reactions were carried out at room temperature.
3.4 | Effect of base on Suzuki‐Miyaura
cross‐coupling reaction
In the outset, the effectiveness of different bases such as
K2CO3, Na2CO3, NaOH, KOH, Et3N Na3PO4.12H2O,
Cs2CO3 and KF were examined in model Suzuki‐Miyaura
cross‐coupling reaction at room temperature using EtOH:
H2O (1:1) solvent system and MNPs‐MIC‐Pd nano-
magnetic catalyst (0.025 mol% Pd with respect to aryl
halide) (Table 1). Na2CO3 and K2CO3 bases gave excellent
yield (Table 1, entries 3 and 11) while NaOH, KOH, Et3N,
Na3PO4.12H2O and Cs2CO3 resulted in lesser conversion
(Table 1, entries 12–16). However, using base KF led to
low conversion (Table 1, entry 17).
3.7 | Effect of time on Suzuki‐Miyaura
cross‐coupling reaction
To know the effect of time, the model Suzuki‐Miyaura
cross‐coupling reaction was carried out at different time
intervals with MNPs‐MIC‐Pd nanomagnetic catalyst as
depicted in Table 1. Initially, at 5 min 82% yield was
obtained (Table 1, entry 24) and subsequently, at
10 min a higher conversion or maximum yield was
obtained (Table 1, entry 3). Further increase in time
beyond 20 min does not improve the yield (Table 1,
entries 25–29). Hence, 10 min is the optimal reaction time
for the model Suzuki‐Miyaura cross‐coupling reaction.
3.5 | Effect of solvent on Suzuki‐Miyaura
cross‐coupling reaction
The efficiency of a variety of solvents such as EtOH, H2O,
EtOH:H2O (1:1), CH3CN, methanol (MeOH), THF, Tolu-
ene, DCM, DMF and isopropanol (IPA) were studied in
model Suzuki‐Miyaura cross‐coupling reaction at room
temperature using MNPs‐MIC‐Pd nanomagnetic catalyst
(0.025 mol% Pd with respect to aryl halide). The results
indicated that reaction went well with polar solvents such
as EtOH, H2O, EtOH:H2O (1:1) and MeOH (Table 1,
entries 1–3 and 5) except with CH3CN, DCM and DMF
(Table 1, entries 4, 8 and 9). Surprisingly, MNPs‐MIC‐Pd
nanomagnetic catalyst did not show any catalytic activity
in THF, toluene and isopropanol solvents (Table 1,
entries 6, 7 and 10).
3.8 | Effect of catalyst ratio on
Suzuki‐Miyaura cross‐coupling reaction
The quantity of catalyst plays a major role in Suzuki–
Miyaura cross‐coupling reactions. Hence, in order to find
out the suitable quantity of the MNPs‐MIC‐Pd nano-
magnetic catalyst, various catalyst ratios 0.02, 0.025, 0.03,
0.035, 0.04 and 0.045 mol% Pd were used in the model
Suzuki‐Miyaura cross‐coupling reaction (Table 2). A max-
imum yield was obtained using 0.025 mol% Pd of the
MNPs‐MIC‐Pd nanomagnetic catalyst (Table 2, entry 2).
Further, use of higher quantities of the MNPs‐MIC‐Pd
nanomagnetic catalyst (0.03, 0.035, 0.04 and 0.045 mol%
Pd) does not increase the conversion (Table 2, entries
3–6). Hence, 0.025 mol% Pd of MNPs‐MIC‐Pd nano-
magnetic catalyst is best catalyst quantity for model
Suzuki–Miyaura cross‐coupling reaction (Table 2, entry 2).
3.6 | Effect of temperature on
Suzuki‐Miyaura cross‐coupling reaction
To investigate the catalytic activity of MNPs‐MIC‐Pd
nanomagnetic catalyst towards Suzuki‐Miyaura cross‐
coupling reaction at varying temperatures, the model
reaction was carried out at different temperatures as
TABLE 2 Suzuki–Miyaura cross‐coupling in presence of MNPs‐MIC‐Pd nanomagnetic catalyst with various catalyst ratios for the model
reactiona
Entry
Base
Solvent
Temperature (°C)
Pd (mol %)
Yield (%)b
1
2
3
4
5
6
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
RT
RT
RT
RT
RT
RT
0.02
73
94
94
94
94
94
0.025
0.03
0.035
0.04
0.045
aReaction conditions: 4‐bromoanisole (1.0 mmol), phenylboronic acid (1.1 mmol), Na2CO3 (2.2 mmol) and EtOH:H2O (1:1) 10 ml in air.
bIsolated yield after separation by column chromatography.

14 of 22
KEMPASIDDHAIAH ET AL.
TABLE 3 Suzuki‐Miyaura cross‐coupling reactions between aryl halides with arylboronic acids catalyzed by MNPs‐MIC‐Pd nanomagnetic
catalysta
Entry
Aryl halide
Product
Time (h)
Yield (%)b
1
0.08
99
2
3
4
0.08
0.5
98
84
98
0.08
5
0.16
94
6
7
0.08
0.08
95
98
8
0.16
0.16
24
98
94
64
9
c10
c11
c12
13
24
65
89
24
0.16
92
(Continues)

KEMPASIDDHAIAH ET AL.
15 of 22
TABLE 3 (Continued)
Entry
Aryl halide
Product
Time (h)
Yield (%)b
14
0.33
90
c15
24
68
16
17
0.5
92
98
0.08
18
19
0.16
1.0
98
96
20
21
0.16
0.16
95
85
22
23
1.0
81
88
0.16
24
25
0.16
1.0
83
80
aReaction conditions: aryl halide (1.0 mmol), arylboronic acid (1.1 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.025 mol% Pd with respect to aryl halide),
Na2CO3 (2.2 mmol) and EtOH:H2O (1:1) (10 ml) in air.
bIsolated yield after separation by column chromatography; average of two runs.
cReactions were carried out at 70 °C.
of arylboronic acids with a range of aryl halides under
3.9 | Suzuki‐Miyaura cross‐coupling
the aforementioned optimized conditions and the results
are summarized in Table 3. The presented Suzuki–
Miyaura cross‐coupling reaction procedure is very simple,
convenient and has the capability to bear a wide variety
reactions of different aryl halides
To investigate the scope and generality of the Suzuki–
Miyaura cross‐coupling reaction we studied the reaction

16 of 22
KEMPASIDDHAIAH ET AL.
of functional groups. All the aryl bromides with
electron‐withdrawing or electron releasing groups react
with arylboronic acids to afford the corresponding prod-
ucts in high yields (Table 3, entries 2, 5, 8, 9, 12, 14–19,
22 and 25) except 2‐bromobenzaldehyde (Table 3, entry
10) and 4‐bromobenzaldehyde (Table 3, entry 11).
Hence, it can be concluded that the reaction yield was
not dependent on the electronic properties of the substit-
uent on the aryl bromides. Conversely, aryl iodides gave
excellent yields as expected (Table 3, entries 1, 4, 6, 7,
13, 20, 21, 23 and 24). On the other hand, aryl chloride
gave lesser yield compared with their bromide and
iodide counter parts under the same reaction conditions
(Table 3, entry 3) as the C–Cl bond strength is high due
to the stronger 2s–3p interaction. These results indicated
that our newly prepared MNPs‐MIC‐Pd nanomagnetic
catalyst is good catalyst for Suzuki–Miyaura cross‐
coupling
reaction.
Additionally,
MNPs‐MIC‐Pd
nanomagnetic catalyst was further studied towards selec-
tivity through conducting the Suzuki–Miyaura cross‐
coupling reaction using the optimized reaction condi-
tions in the absence of aryl bromide. The biphenyl
homo‐coupled product was negligible even after longer
reaction time. Hence, it is concluded that our newly syn-
thesized MNP‐MIC‐Pd nanomagnetic catalyst is highly
selective.
TABLE 4 Recyclability of MNPs‐MIC‐Pd nanomagnetic catalyst in Suzuki‐Miyaura cross coupling reactions of bromobenzene and
phenylboronic acida
Entry
Base
Solvent
Temperature (°C)
Catalyst run
Fresh
Yield (%)b
1
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
98
98
98
98
98
97
97
97
96
96
95
2
1st recycle
2nd recycle
3rd recycle
4th recycle
5th recycle
6th recycle
7th recycle
8th recycle
9th recycle
10th recycle
3
4
5
6
7
8
9
10
11
aReaction conditions: bromobenzene (1.0 mmol), phenylboronic acid (1.1 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.025 mol% Pd with respect to aryl
halide), Na2CO3 (2.2 mmol) and EtOH:H2O (1:1) (10 ml) in air.
bIsolated yield after separation by column chromatography.
FIGURE 11 The recycling efficiency of
MNPs‐MIC‐Pd nanomagnetic catalyst in
Suzuki‐Miyaura cross‐coupling reaction of
bromobenzene and phenylboronic acid

KEMPASIDDHAIAH ET AL.
17 of 22
revealed that catalyst can be reused for minimum ten
times in Suzuki‐Miyaura cross‐coupling reactions without
loss of its catalytic activity (Figure 11) (Table 4, entries
1–11). After ten cycles, recovered MNPs‐MIC‐Pd
nanomagnetic catalyst was further characterized by
FESEM and FT‐IR spectroscopy. The FESEM image
(Figure 5b) and FT‐IR spectra (Figure 2b) of reused
MNPs‐MIC‐Pd nanomagnetic catalyst indicated that
there is no change in surface morphology and chemical
composition. This result exhibits the high stability of the
MNPs‐MIC‐Pd nanomagnetic catalyst.
3.10 | Recyclability of the MNPs‐MIC‐Pd
nanomagnetic catalyst in Suzuki‐Miyaura
cross‐coupling reactions
For convenient applications of a heterogeneous catalyst,
recyclability of the catalyst is a very important factor. To
explain this matter, catalytic recyclability experiments
were carried out for the Suzuki‐Miyaura cross‐coupling
reaction of bromobenzene with phenylboronic acid. After
completion of Suzuki‐Miyaura cross‐coupling reactions,
MNPs‐MIC‐Pd nanomagnetic catalyst was separated by
applying an external magnet and washed thoroughly with
H2O (2 x 10 ml), followed by EtOH (2 x 10 ml) and dried
at 45 °C overnight. Then the same MNPs‐MIC‐Pd
nanomagnetic catalyst was reused for next cycle without
any further purification. Recycling efficiency of MNPs‐
MIC‐Pd nanomagnetic catalyst is tabulated in Table 4.
The recyclability of MNPs‐MIC‐Pd nanomagnetic catalyst
3.11 | Catalytic activity of MNPs‐MIC‐Pd
nanomagnetic catalyst in Mizoroki–heck
cross‐ coupling reactions
In the second part of our study, we explored the applica-
bility of MNPs‐MIC‐Pd nanomagnetic catalyst in the
Mizoroki–Heck cross‐coupling reaction of aryl halides
with styrene and tert‐butyl acrylate. In order to optimize
the reaction conditions, we have selected the cross‐
coupling of iodobenzene with styrene as a model reac-
tion (Scheme 3). The reaction conditions were optimized
through a series of reactions as listed in Table 5. In
SCHEME
3
Mizoroki‐Heck cross‐coupling reaction of
iodobenzene with styrene in presence of MNPs‐MIC‐Pd
nanomagnetic catalyst
TABLE 5 Optimization of reaction conditions for the model Mizoroki–Heck cross‐coupling reaction in presence of MNPs‐MIC‐Pd
nanomagnetic catalysta
Entry
1
Solvents
Base
Pd (mol %)
0.05
Temperature (°C)
Time (h)
2.0
Yield(%)b
H2O
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
K2CO3
RT
RT
RT
70
‐
2
EtOH
0.05
2.0
‐
3
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
EtOH:H2O(1:1)
DMF
0.05
1.5
95
95
81
85
85
89
95
85
88
74
95
75
53
61
‐
4
0.05
0.5
5
0.05
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
RT
0.16
0.33
0.33
0.5
6
0.05
7
0.05
8
Na2CO3
Na2CO3
K2CO3
0.05
9
0.05
1.0
10
11
12
13
14
15
16
17
0.05
0.5
K2CO3
0.05
1.0
Na2CO3
Na2CO3
NaOH
0.025
0.075
0.05
1.0
1.0
1.0
CS2CO3
Na2CO3
Na2CO3
0.05
1.0
0.05
0.5
MeOH
0.05
0.5
aReaction conditions: iodobenzene (1.0 mmol), styrene (1.2 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.05 mol % Pd with respect to aryl halide), base
(2.0 mmol) and solvent (10 ml) in air.
bIsolated yield after separation by column chromatography.

18 of 22
KEMPASIDDHAIAH ET AL.
TABLE 6 Mizoroki–Heck cross‐coupling of different aryl halides with alkenes in the presence of MNPs‐MIC‐Pd nanomagnetic catalysta
Entry
Aryl halide
Alkene
Product
Time (h)
Yield (%)b
1
1.0
95
2
3
4
1.5
6.0
24
91
82
92
5
6
7
8
24
6
90
58
6
52
24
Trace
9
16
24
82
10
Trace
11
12
13
14
1.0
2.0
5.0
24
91
88
78
90
(Continues)

KEMPASIDDHAIAH ET AL.
19 of 22
TABLE 6 (Continued)
Entry
Aryl halide
Alkene
Product
Time (h)
Yield (%)b
15
24
84
16
16
73
aReaction conditions: aryl halide (1.0 mmol), alkene (1.2 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.05 mol% Pd with respect to aryl halide), Na2CO3
(2.0 mmol) and EtOH:H2O (1:1) 10 ml in air.
bIsolated yield after separation by column chromatography; average of two runs.
order to choose the reaction solvent, various solvents
(H2O, EtOH, EtOH:H2O (1:1), DMF and MeOH) and
amounts of MNPs‐MIC‐Pd nanomagnetic catalyst were
examined. The good results were obtained in EtOH:
H2O (1:1) solvent mixture using 0.05 mol% Pd of
MNPs‐MIC‐Pd nanomagnetic catalyst (Table 5, entry 9).
In addition, the model reaction was examined using
numerous bases such as Na2CO3, K2CO3, NaOH and
CS2CO3 and the good results were observed using two
equivalents of Na2CO3 (Table 5, entry 9). Furthermore,
the effect of temperature was studied and found out that
the reaction proceeded well at room temperature itself
(Table 5, entry 9).
After the optimization of the reaction conditions, a
variety of aryl halides having numerous functional groups
were reacted with styrene and tert‐butyl acrylate under the
optimized conditions and the results are summarized in
Table 6. All the aryl bromides and aryl iodides having
electron‐withdrawing or electron‐releasing groups reacted
with olefins to afford the corresponding products in high
yields (Table 6, entries 1, 2, 4–7, 9, 11, 12 and 14–16) except
1‐bromo‐4‐tertiarybutylbenzene (Table 6, entry 8) and 4‐
iodophenol (Table 6, entry 10). However, aryl chlorides
gave lower yields when compared to their iodide and bro-
mide counterparts (Table 6, entries 3 and 13). Therefore,
obtained results concluded that MNPs‐MIC‐Pd nano-
magnetic catalyst is an efficient catalyst towards
Mizoroki–Heck cross‐coupling reactions for the synthesis
of various substituted olefins.
investigate this issue, the recyclability of the MNPs‐
MIC‐Pd nanomagnetic catalyst was examined for the
cross‐coupling of iodobenzene with styrene under the
optimized conditions. After the completion of the reac-
tion, the MNPs‐MIC‐Pd nanomagnetic catalyst was easily
separated from the products using an external magnet
and used in the next round of reaction after washing with
H2O (2 x 10 ml) followed by EtOH (2 x 10 ml) and dried
at 45 °C. As shown in Figure 12, the MNPs‐MIC‐Pd
nanomagnetic catalyst used over five runs without any
significant loss of activity or palladium leaching. From
sixth recycle onwards, a decrease in catalytic activity
was observed (Table 7). The FESEM image and FT‐IR
spectrum of five times recycled MNPs‐MIC‐Pd nano-
magnetic catalyst was recorded. No change in the mor-
phology was observed through the FESEM image
(Figure 5c) after recycling up to five times which is fur-
ther confirmed by the FT‐IR spectrum (Figure 2c) which
shows that the MNPs‐MIC‐Pd nanomagnetic catalyst is
intact after recycling.
3.12 | Recyclability of the MNPs‐MIC‐Pd
nanomagnetic catalyst in Mizoroki–heck
cross‐coupling reactions
The recyclability of catalyst is an important feature
required for a catalyst for commercial applications. To
FIGURE
12 Recycling
efficiency
of
MNPs‐MIC‐Pd
nanomagnetic catalyst in the reaction of iodobenzene and styrene

20 of 22
KEMPASIDDHAIAH ET AL.
TABLE 7 Recyclability of MNPs‐MIC‐Pd nanomagnetic catalyst in Mizoroki–Heck cross coupling reactions of idobenzene with styrenea
Temperature
(°C)
Catalyst
Run
Yield(%)b
Entry
Base
Solvent
1
2
3
4
5
6
7
8
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
RT
RT
RT
RT
RT
RT
RT
RT
Fresh
95
95
95
95
92
91
88
85
1st recycle
2nd recycle
3rd recycle
4th recycle
5th recycle
6th recycle
7th recycle
aReaction conditions: iodobenzene (1.0 mmol), styrene (1.2 mmol), MNPs‐MIC‐Pd nanomagnetic catalyst (0.05 mol% Pd with respect to aryl halide), Na2CO3
(2.0 mmol) and EtOH:H2O (1:1) 10 ml in air.
bIsolated yield after separation by column chromatography; average of two runs.
mixture, ICP‐AES analysis was carried out for both the
recovered catalyst as well as reaction mixture and found
that the Pd content in MNPs‐MIC‐Pd nanomagnetic cata-
lyst was 4.82% (w/w) and that in the reaction mixture was
0.000419% (w/w) (4.19 ppm). This confirms that the
leaching of Pd from the MNPs‐MIC‐Pd nanomagnetic
catalyst is negligible in the reaction possibly because of
the specific design of nanomagnetic catalyst.
3.13 | Catalyst leaching study
One problem that should be addressed when using het-
erogeneous catalysts is metal leaching in to the reaction
solution. The leaching of palladium from catalyst was
studied for the model Suzuki–Miyaura cross‐coupling
reaction in the optimized reaction conditions. The
MNPs‐MIC‐Pd nanomagnetic catalyst was recovered after
5 min by an external magnet and the same reaction was
further continued for more than 2 hr and the reaction
was monitored by TLC. Further conversion was not
observed and the isolated yield was 82%. After recovery
of MNPs‐MIC‐Pd nanomagnetic catalyst from reaction
3.14 | Comparison of catalysts
Comparison of catalytic activity of MNPs‐MIC‐Pd
nanomagnetic catalyst with previously reported catalysts
TABLE 8 Comparison of results in Suzuki‐Miyaura cross‐coupling reaction between bromobenzene and phenylboronic acid of other
reported catalysts with the MNPs‐MIC‐Pd nanomagnetic catalyst
Entry
Catalyst
Solvent
Temp. (°C)
Time (h)
Yield (%)
Ref.
[47]
1
Click‐catalyst A
Fe3O4@SiO2‐EDTA‐Pd
Si‐IL@Pd(0)NPs
Pdnp@MNP
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
Toluene
70
70
0.75
2
90
97
95
97
85
95
98
93
87
85
69
95
95
98
[48]
[49]
[43]
[50]
[51]
[52]
[52]
[53]
[40]
[41]
[38]
[39]
2
3
50
4
4
60
4
5
Fe3O4/SiO2‐NH2/SA/Pd
NHC‐Pd Complex
P‐PdNPs/CMK‐3
AA‐PdNPs/CMK‐3
Pd/IL‐NH2/SiO2/Fe3O4
SB‐Pd@MNPs
75
1
6
DMF:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
EtOH:H2O (1:1)
50
6
7
40
0.5
0.5
5
8
40
9
25
10
11
12
13
14
RT
RT
70
0.5
3
MNPs@SB‐Pd
NHC‐Pd@MNPs
NO2‐NHC‐Pd@Fe3O4
MNP‐MCP‐Pd
1
RT
RT
2
0.08
Present work

KEMPASIDDHAIAH ET AL.
21 of 22
TABLE 9 Comparison of results in Mizoroki–Heck cross‐coupling reaction between iodobenzene and styrene of other reported catalysts
with the MNPs‐MIC‐Pd nanomagnetic catalyst
Entry
Catalyst
Solvent
DMF
Temp. (°C)
Time (h)
Yield (%)
Ref.
[54]
1
2
3
4
5
6
7
8
9
SiO2@Fe3O4‐Pd
Catalyst
100
90
8
24
3
95
100
96
[55]
[56]
[57]
[58]
[59]
[60]
[39]
DMF
MNP@NHC‐Pd
Pd‐MNPSS
DMF
140
100
RT
140
120
80
H2O
4
89
Pd‐imine@MNPs/Cs
Catalyst
H2O
0.33
15
0.16
5
75
NMP
97
Pd‐Catalyst
DMF
98
NO2‐NHC‐Pd@Fe3O4
MNPs‐MCP‐Pd
MeCN
EtOH:H2O (1:1)
96
RT
1
95
Present work
for Suzuki‐Miyaura and Mizoroki‐Heck cross‐coupling
reactions are presented in Table 8 and Table 9 respec-
tively. Comparison of the results shows that our new
MNPs‐MIC‐Pd nanomagnetic catalyst is extremely active
catalyst towards both Suzuki‐Miyaura and Mizoroki‐
Heck cross‐coupling reactions under mild reaction condi-
tions. Also, MNPs‐MIC‐Pd nanomagnetic catalyst is supe-
rior in terms of non‐toxicity, price, stability and ease of
separation than the previously reported ones. Further-
more, the recyclability MNPs‐MIC‐Pd nanomagnetic cat-
alyst is easier and rapid than those of other reported
catalysts.[38–41,43,47–60]
ORCID
Siddappa A. Patil https://orcid.org/0000-0002-2855-5302
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