Copper(II) incorporated functionalized polystyrene catalyzed: N -arylation of amides under solvent free condition with broad substrate scope

Article abstract of DOI:10.1039/c6ra24459a

We demonstrate here, a new polystyrene supported Cu(ii) catalyzed proficient synthetic methodology for the facile N-arylation of aromatic, aliphatic, cyclic and heterocyclic amides with aryl halides under neat conditions. The catalyst, PS-Cu(ii)-ala, was prepared through the grafting of copper metal on a polystyrene-β-alanine imine network. The catalyst shows a wide range of substrate scope and excellent functional group tolerance, and produces the desired anilides in mostly high yields. The material is thoroughly characterized by DRS-UV, FT-IR, AAS, FE-SEM, TGA analysis and energy dispersive X-ray (EDX) studies. The catalyst can be easily recovered from the reaction medium and reused without significant loss of its catalytic activity suggesting future potential of this catalyst.

Full text of DOI:10.1039/c6ra24459a

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Copper(II) incorporated functionalized polystyrene catalyzed N-arylation of
amides under solvent free condition with broad substrate scope
Md. Mominul Islam,a┼ Mita Halder,b┼ Anupam Singha Roy,*c,d Sauvik
Chatterjee,e Asim Bhaumik*e and Sk. Manirul Islam*a
aDepartment of Chemistry, University of Kalyani, Kalyani, Nadia, 741235, W.B., India.
bDepartment of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700 009, India.
cCatalytic Conversion & Processes Division, CSIR-Indian Institute of Petroleum, Dehradun
248005, India.
dEuropean Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
eDepartment of Material Science, Indian Association for the Cultivation of Science,
Kolkata - 700032, India.
┼These authors contributed equally to this manuscript.
Abstract
We demonstrate here, a new polystyrene supported Cu(II) catalyzed proficient synthetic
methodology for the facile Nꢀarylation of aromatic, aliphatic, cyclic and heterocyclic amides
with aryl halides under neat condition. The catalyst, PSꢀCu(II)ꢀala, was prepared through the
grafting of copper metal on polystyreneꢀβꢀalanine imine network. The catalyst shows wide
range of substrate scope, excellent functional group tolerance, and produces the desired
anilides in mostly high yields. The material is thoroughly characterized by DRSꢀUV, FTꢀIR,
AAS, FEꢀSEM, TGA analysis and energy dispersive Xꢀray (EDX). The catalyst can be easily
recovered from the reaction medium and reused without significant loss of its catalytic
activity suggesting future potential of this catalyst.
1

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Keywords: Polymer supported Cu(II) catalyst, Oneꢀpot synthesis, Cross coupling, CꢀN bond
formation, Neat condition.
*Corresponding authors:
Dr. Anupam Singha Roy, European Bioenergy Research Institute, Aston University,
Birmingham B4 7ET, UK. Eꢀmail: a.singhaꢀroy@aston.ac.uk
Prof. Asim Bhaumik, Department of Material Science, Indian Association for the
Cultivation of Science, Kolkataꢀ700032, India, Phone: +91ꢀ33ꢀ2473ꢀ4971; Fax: +91ꢀ33ꢀ
2473ꢀ2805, eꢀmail: msab@iacs.res.in
Dr. Sk. Manirul Islam, Department of Chemistry, University of Kalyani, Kalyani, Nadia,
741235, W.B., India. Phone: +91ꢀ33ꢀ2582ꢀ8750, Fax: +91ꢀ33ꢀ2582ꢀ8282, Eꢀmail:
manir65@rediffmail.com
1 Introduction
The transition metal catalyzed crossꢀcoupling of amides and aryl halides is one of the most
proficient and powerful method for the synthesis of Nꢀaryl amides, as it plays a significant
role in the synthesis of several biologically, medicinally and materially potent molecules.1
Arguably, aryl amides are one of the most important part in the synthesis of natural as well as
synthetic products.2 In particular, Nꢀarylation involving heterocyclic entities generate highly
significant biologically active molecules and drugs3 as outlined in Figure 1.
O
N
O
N
N
O
O
NH
Methyprylon
EtO2C
N
O
Precursor of drug
against Alzheimer
Tremogenic
activity
Figure 1. Potent molecules bearing amide skeleton.
2

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As a result, amide skeleton synthesis has become one of the most challenging topics towards
the synthetic organic chemists. More than a century ago, after the pioneer work performed by
Goldberg,4 metal catalyzed CꢀN crossꢀcoupling has obtained a significant attention. However,
the traditional methodologies, involving harsh reaction condition, longer reaction time and
low functional group tolerance, require to be developed further. Notably, a lot of alternative
methods for the synthesis of amide bond have been developed. Most of these reaction
pathways are catalyzed by a variety of transition metal catalysts like Fe,5 Co,6 Ni,7 and Pd8
etc. But easy availability, cheap and environmentally benign nature of copper metal have
attracted our concentration to it. However, a number of copper catalyzed crossꢀcoupling of
amides with aryl halides are reported in literature.9 But, homogeneous nature of the catalyst,
lack of recyclability, possibility of metal contamination in end product, utilization of
additives, use of hazardous solvents and obviously use of expensive ligand system etc. insist
to develop a greener alternative, so that, the catalyst become economically cheap and can be
reused further. To avoid these drawbacks, a variety of heterogeneous catalysts were
developed through immobilization of copper metal on various kind of solid supports.10 In
recent times, polymer supported ligands have been developed to immobilize Cu metal onto
it.11 Besides, application of hazardous solvents in the catalytic system makes the
methodology expensive and harmful to the nature. Our group has already explored a number
3

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Scheme 1. Polymeric PSꢀCu(II)ꢀala catalyzed CꢀN cross coupling reactions.
of heterogeneous polymer supported metal catalyst for C–N, CꢀO and C–C cross coupling
reactions.12 Herein, for the first time we report, polymeric βꢀalanine incorporated Cu(II)
catalyzed CꢀN bond formation through the mild and efficient coupling of aromatic, aliphatic,
cyclic and heterocyclic amides with aryl halides under solvent free condition (Scheme 1).
This synthetic protocol may offer potential route for the progress of carbonꢀheteroatom bond
forming reactions employing catalytic amount of PSꢀCu(II)ꢀala.
2 Results and Discussion
To evaluate the optimal reaction conditions, a series of reactions were performed with the
variation of reaction parameters like base, solvent, temperature and the catalyst amount etc.
for the representative reaction of benzamide (1a) with iodobenzene (2a). The results are
summarized in Table 1.
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Table 1 Optimization of reaction conditions.a
O
I
O
PS-Cu(II)-ala
NH2
N
H
+
base, solvent
temp.
3a
2a
1a
Entry
Amount of
Solvent
Base
Temperature Yield
Catalyst (mg)
(°C)
140
140
120
110
120
70
(%)b
ꢀ
1
2
ꢀ
DMF
DMF
pꢀxylene
H2O
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
Cs2CO3
NaHCO3
K3PO4
KF
15
15
15
15
15
15
15
15
15
15
10
25
15
1.8
ꢀ
60
00
00
92
5
3
4
5
neat
CH3CN
NMP
neat
6
7
70
00
62
85
17
10
79
90
ꢀ
8
120
120
120
120
120
120
rt
9
neat
10
11
12
13
14
15c
16d
17e
neat
neat
neat
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
neat
neat
neat
120
120
120
67
78
00
neat
15
neat
aReaction condition: 1a (1.0 mmol), 2a (1.1 mmol), base (1.0 mmol), solvent (2.5 mL), 15 h.
c
d
bIsolated yield. reaction using copper(II) acetate (0.9 mol%). reaction using copper(II)
acetate and βꢀalanine (1:1). ereaction using polymeric ligand (3).
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The best result in terms of yield was obtained using 15 mg (0.9 mol%) of the Cu(II) catalyst
in solvent free condition for 15 h at 120 °C (Table 1, Entry 5). Various bases viz. K2CO3,
Cs2CO3, NaHCO3, K3PO4 and KF were used for this reaction. But K2CO3 was found the best.
Though, NaHCO3 gave comparable product yield. No product was formed at room
temperature. Various solvents viz. DMF, pꢀxylene, H2O, NMP, CH3CN were used for this
reaction, but no one can produce better yield. Polar, low coordinating solvents like DMF and
CH3CN gave low yields whereas water did not initiate the reaction. Water may form a
boundary between the amide and catalyst which disturbs their interaction. Because the
binding of the catalyst to the amide is the initial step of the reaction.9d The catalyst showed
best activity in neat condition at 120 °C. Low yield of the desired Nꢀarylated product was
obtained when homogeneous copper(II) acetate was used as catalyst (Table 1, Entry 15). The
yield slightly increases from the previous one when the mixture of copper salt and βꢀalanine
was used as catalytic system (Table 1, Entry 16). But the yield in the above two cases was
low compared to the polymer supported copper catalyst. No product was obtained when
polymeric ligand (3) was used (Table 1, Entry 17).
After getting the optimal condition, a series of reactions were carried out using aromatic
amide with various aryl halides to explore the catalytic scope. The results are concise in
Table 2. It is quite evident that, besides iodoꢀ, bromobenzene also gives good yield (3a and
3b, Table 2). However, both electron withdrawing and donating groups attached to the phenyl
ring of the aryl halide partner are equally compatible for this reaction.
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Table 2 Nꢀarylation of aromatic amide with aryl halides.a
X
O
O
HN
PS-Cu(II)-ala
FG
NH2
+
°
neat, 120 C
K2CO3, 16 h
FG
3a-db
1
2
O
O
N
N
H
H
3a, X=I, 92% (12.27 h-1)
X=Br, 80% (10.67 h-1)
3b, X=I, 89% (11.87 h-1)
X=Br, 78% (10.40 h-1)
NO2
OMe
O
O
N
H
N
H
3c, 87% (11.60 h-1)
3d, 90% (12.0 h-1)
aConditions:1 (1.0 mmol), 2 (1.1 mmol), catalyst (15 mg, 0.9 mol%), K2CO3 (1.0 mmol),
neat, 120 oC, 15 h, under air. bIsolated yield. TOF given in parentheses.
Next, we investigate our synthetic protocol for the crossꢀcoupling of the aryl halides with
aliphatic amide (Table 3). Acetamide undergoes this CꢀN coupling reaction very smoothly
with iodobenzene as well as bromobenzene resulting good yield.
Table 3 Nꢀarylation of acetamide with aryl halides.a
O
PS-Cu(II)-ala
O
X
FG
+
°
neat, 120 C
HN
5a-db
NH2
O
GF
K2CO3, 15 h
4
2
O
N
N
H
H
5b, 88% (11.73 h-1)
5a, X=I, 91% (12.13 h-1)
X=Br, 83% (11.07 h-1)
OMe
O
O
N
N
N
H
H
5d, X=I, 90% (12.0 h-1)
X=Br, 84% (11.2 h-1)
5c, 87% (11.6 h-1)
aConditions: 4 (1.0 mmol), 2 (1.1 mmol), catalyst (15 mg, 0.9 mol%), K2CO3 (1.0 mmol),
neat, 120 oC, 15 h, under air. b Isolated yield. TOF given in parentheses
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Next, we have studied that cyclic amides also undergo CꢀN crossꢀcoupling reaction to their
corresponding products. The results are concise in Table 4. 2ꢀoxazolidinone reacts with
iodobenzene without any difficulty to give the product in 82% yield (7d, Table 4). We are
pleased to state that along with six membered cyclic amide, seven and eight membered cyclic
amides also go through this coupling reaction to furnish their product in good to moderate
yields (7a, 7b and 7c, Table 4).
Furthermore, our catalytic system equally works proficiently for the crossꢀcoupling of
heterocyclic amides with iodobenzene (Table 5). Thiopheneꢀ2ꢀcarboxamide and Furanꢀ2ꢀ
carboxamide both go through this CꢀN coupling reaction effortlessly. 2ꢀiodo pyridine reacts
with Furanꢀ2ꢀcarboxamide to gives the corresponding heterocyclic product in very good yield
(9e, Table 5).
Table 4 Nꢀarylation of cyclic amides with aryl halides.a
I
O
O
HN
PS-Cu(II)-ala
FG
NH2
+
°
neat, 120 C
K2CO3, 20 h
FG
7a-db
6
2
O
O
N
N
7a, 75% (7.5 h-1)
7b, 70% (7 h-1)
O
O
N
O
N
7d, 82% (8.2 h-1)
7c, 62% (6.2 h-1)
aConditions: 6 (1.0 mmol), 2 (1.2 mmol), catalyst (15 mg, 0.9 mol%), K2CO3 (1.0 mmol),
neat, 120 oC, 20 h, under air. b Isolated yield. TOF given in parentheses.
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Table 5 Nꢀarylation of heterocyclic amides with aryl halides.a
I
O
O
HN
PS-Cu(II)-ala
FG
NH2
+
°
X
neat, 120 C
X
K2CO3, 16 h
FG
9a-db
8
2
O
O
N
N
H
H
S
O
9b, 84% (10.5 h-1)
9a, 85% (10.63 h-1)
OMe
O
OMe
O
N
H
N
H
O
S
9d, 81% (10.13 h-1)
9c, 80% (10 h-1)
O
N
N
H
O
9e, 84% (10.5 h-1)
a
Conditions: 8 (1.0 mmol), 2 (1.1 mmol), catalyst (15 mg, 0.9 mol%), K2CO3 (1.0 mmol),
neat, 120 oC, 16 h, under air. b Isolated yield. TOF given in parentheses.
The most possible reaction mechanism for this PSꢀCu(II)ꢀala catalyzed one pot synthesis of
Nꢀarylated products follows the well recognized mechanisms reported in literature.9d,13
3 Experimental
3.1. Chemicals: Chloromethylated polystyrene (5.5 mmol Cl/gm of resin) was purchased
from SigmaꢀAldrich. All other chemicals used for these investigation purposes were
purchased from commercial sources and were used without purification. Before use, all
solvents were distilled and dried following the standard process.
3.2. Synthetic pathway of the PS-Cu(II)-ala
Synthetic procedure of functionalized polymer supported ligand: The ligand (3) was prepared
from the organically modified chloromethylated polystyrene beads (1) according to literature
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procedure. In first step, polystyrene beads (1) were functionalized to –CHO groups to form
(2)14 and then react with βꢀalanine to give ligand (3)12a, b as the final product.
Loading of metal ions on to the functionalized ligand (3): Copper acetate (30 mg) in acetic
acid solution (8 mL) and 0.5 gm of functionalized polymeric ligand (3) were heated at reflux
condition for 22 h. The ensuing solid (metalꢀloaded functionalized polymer 4) was filtered
and washed with water followed by methanol, repetitively. Finally it was dried in oven at 90
oC for 5 h under vacuum.
3.4. Characterization techniques: A PerkinElmer 2400 C elemental analyzer was used to
collect microꢀanalytical data (C, H and N). The FTꢀIR spectra of the samples were recorded
from 400 to 4000 cmꢀ1 on a PerkinElmer FTꢀIR 783 spectrophotometer. A Mettler Toledo
TGA/SDTA 851 instrument was used for TGA. The morphology of the functionalized
polystyrene and complex was analyzed using a scanning electron microscope (Zeiss EVO40,
UK) equipped with EDX facility. The copper content in the catalyst was determined using a
Varian AA240 atomic absorption spectrophotometer. The Xꢀray photoluminescence
spectroscopic analysis has been performed on a Omicron Nanotechnology GmbH. The EPR
spectra were recorded using a JESꢀFA200ESR spectrometer (JEOL). NMR spectra were
monitored on a Bruker AMXꢀ 400 NMR spectrophotometer (400 MHz for 1H NMR) using
tetramethylsilane as internal standard.
3.5. General procedure for the N-arylation of amides: A mixture of benzamide (121 mg,
1.0 mmol), iodobenzene (~0.2 mL, 1.1 mmol), K2CO3 (138 mg, 1.0 mmol), and PSꢀCu(II)ꢀala
(0.9 mol%) were heated at 120 ºC (oil bath temperature) for 15 h under air. The reaction
mixture was allowed to cool and extracted with ethyl acetate (3 × 20 mL). The organic part
was washed with brine, dried over Na2SO4 (anhy.), and evaporated to leave the crude
product, which was purified by column chromatography over silica gel with pet ether/ethyl
acetate (85:15) as eluent to furnish pure Nꢀphenyl benzamide (3a, 181 mg, 92 %) as a white
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1
crystalline solid. H NMR (400 MHz, CDCl3) δ 7.82 ꢀ 7.80 (m, 2H), 7.73 (bs, 1H), 7.59 ꢀ
7.57 (m, 2H), 7.51 – 7.41 (m, 3H), 7.33 ꢀ 7.29 (m, 2H), 7.11 ꢀ 7.07 (m, 1H).
P
P
O
P
P
H2N
HO
Cu(OAc)2
AcOH
N
O
DMSO
O
Cu
OAc
AcO
NaHCO3
Cu
N
O
N
CHO
CH2Cl
HO
O
O
(1)
P
(2)
(3)
(4)
Scheme 2. Outline for the synthesis of PSꢀCu(II)ꢀala.
3.6. Characterization of supported copper(II) complex.
The overall synthetic route for the preparation of functionalized polymerꢀsupported
copper(II) catalyst is shown in Scheme 2. The catalyst (PSꢀCu(II)ꢀala) was characterized by
elemental analysis (CHN), AAS, UVꢀVis spectra, IR, SEM, TGA, XPS and EPR.
The elemental analysis data for the functionalized polymeric ligand (3) and PSꢀCu(II)ꢀala (4)
are shown in Table 6. The quantity of the Cu metal in the catalyst was determined using AAS
technique. It is found that the catalyst contains just 4.01 wt% of Cu metal.
Table 6. Chemical composition of functionalized polymer supported ligand (3) and PSꢀ
Cu(II)ꢀala catalyst (4)
Compound
C%
74.95
72.00
H%
6.37
6.04
N%
4.60
4.44
Cu%
Ligand 3
PSꢀCu(II)ꢀala
(4)
ꢀ
4.01 (3.98)a
aCopper content of recycled catalyst after 8th cycles.
FT-IR Study: The link of relationship of βꢀalanine and copper metal onto the support were
established by IR spectra (Figure 2). In the FTꢀIR spectrum (Figure 2a), a new peak arose at
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1705 cmꢀ1 which was confirmed to carbonyl C=O bond stretching vibration of the aldehyde
group while the peak nearly at 1264 cmꢀ1 (due to CꢀCl bond stretching of ꢀCH2Cl) was
absent.15 A new peak at 1632 cmꢀ1 was observed which is assigned for the formation of a
C=N bond in Figure 2b. Due to the complexation of Cu metal with the ligand system, this
band moved to lower wave numbers (Figure 2c). In Figure 2c, two peaks at 1574 cmꢀ1 and
1421 cmꢀ1 were exhibited,16 which assigned to the asymmetric and symmetric vibrations of
the bridging acetate ions (ν COO bridged).
DRS-UV study: The DRS UVꢀVis absorption spectra (Figure 3) of the functionalized
polymeric ligand and copper catalyst (PSꢀCu(II)ꢀala) have been recorded as MgCO3/BaSO4
disc. Both of them exhibited broad band around 265 to 330 nm, which may be ascribed to
π* and π→π* shift in
n→
the phenyl ring moiety. LMCT caused the generation of the band at
around 355 to 375 nm in PSꢀCu(II)ꢀala catalyst.
Figure 2. FTꢀIR spectra of (a) aldehyde functionalized polymer, (b) polymer supported Schiff base
ligand and (c) polymer supported Cu(II) catalyst, PSꢀCu(II)ꢀala.
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Figure 3. DRSꢀUVꢀvis spectra of polymeric ligand (3) and PSꢀCu(II)ꢀala Catalyst.
Scanning Electron Micrographs (SEM) and Energy Dispersive X-ray Analyses (EDX):
The SEM image of the functionalized polymeric ligand (3) and PSꢀCu(II)ꢀala catalyst are
given in Figure 4a and 4b. It is reflected that, reasonably homogeneous but insignificant
variation in the particle size is seen all over the specimens. The existence of the copper metal
in the final copper catalyst is also established by EDAX data (Figure 4c).
Figure 4. SEM images of polymeric ligand (3) (a), PSꢀCu(II)ꢀala Catalyst (b) and EDX plot of PSꢀ
Cu(II)ꢀala Catalyst (c).
TGA analysis: To investigate the thermal stability of the catalyst, the catalyst sample was
o
o
heated at a rate of 10 C minꢀ1 under air over the range of temperature of 30–600 C. The
thermograph is given in Figure 5. The Materials, ligand (3) and copper catalyst (4) are stable
to higher temperature around 400 oC. From the curve we can observed that the heterogeneous
copper catalyst is more stable than the corresponding polymer supported ligand (3).
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Figure 5. Thermograph of polymeric ligand (3), PSꢀCu(II)ꢀala Catalyst (4).
XPS Analysis: The XPS binding energies of Cu 2p1/2 and Cu 2p3/2 are found to be 954 and
934 eV, which is agrees well with +2 oxidation state of Cu in PSꢀCu(II)ꢀala.17 A satellite
peak between these two is characteristic feature of 2p → 3d transition of Cu in +2 oxidation
state.17,18 The amount of Cu atoms present on the surface of PSꢀCu(II)ꢀala is found to be 0.40
atomic per cent. The C1s, O1s, N1s peaks are found at 284 eV, 532 eV and 399 eV
respectively confirms the presence of C, O, N.18 The full range scan is shown in Figure 6e
and the narrow range scan is shown in Figure 6aꢀd.
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Figure 6. XPS data of PSꢀCu(II)ꢀala, narrow range XPS spectrum for (a) Cu 2p, (b) O 1s, (c)
N 1s, (d) C 1s and (e) full range spectrum.
EPR Analysis: The EPR (Electron Paramagnetic Resonance) spectroscopic studies have
been carried out with fresh as well as used catalyst in solid state at room temperature. Both
the EPR spectra show (Figure 7) four hyperfine lines which appear due to the coupling of
unpaired electron of copper with its nucleus.19 This indicates +2 oxidation states of copper for
both the fresh and reused catalysts. This implies the oxidation state of the Cu remained
unchanged after the catalytic reaction.
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Figure 7. EPR spectrum of (a) fresh catalyst and (b) used catalyst
4 Recyclability and Reusability of Cu(II) catalyst:
To evaluate the recyclability and reusability of Cu(II)ꢀcatalyst we performed the Nꢀarylation
reaction of benzamide with iodobenzene under optimized conditions. After completion of the
reaction, the crude reaction mixture was centrifuged. The recovered catalyst was washed
thoroughly using water and methanol respectively. Finally the catalyst was dried in oven at
70 °C for 5 h under vacuum for reactivation. It is quite evident that the catalyst can be
recycled for 8th successful runs without prior loss in its catalytic activity (Figure 8). The
possibility of copper metal leaching was examined by IR spectrum and AAS analysis. The
SEM image also indicates the parallel observation (Figure 9a). The IR spectrum of the reused
catalyst was found to be quite similar with the fresh one (Figure 9b). Finally, the AAS
analysis of the reused catalyst also confirms that the copper content in the reused catalyst
remains almost unchanged after 8th successful catalytic runs (Table 6).
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Figure 8. Recycling experiment of PSꢀCu(II)ꢀala.
Figure 9. SEM image (a) and FTꢀIR spectrum (b) of the reused catalyst
Conclusions
In this context, functionalized polystyrene supported copper(II) catalyst was synthesized and
characterized. CꢀN cross coupling reaction was selected to understand the catalytic activity of
this copper(II) catalyst. The reactions were carried out under neat condition. The scope and
utility of this reaction were broad and environment friendly due to the wide span of the
substrates. Aromatic, aliphatic, cyclic and heterocyclic amides successfully coupled with the
aryl iodide as well as aryl bromide in presence of this copper(II) catalyst. The catalyst
exhibited excellent recyclability. As a result, the troubleꢀfree mode of operation, broad
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substrates scope and good recycling of the catalyst allowed us to go ahead for a good future
of this course in academic in addition to in production industry.
Associated Content
Notes
The authors declare no competing financial interest.
†Electronic Supplementary Information (ESI) available. 1H NMR spectral data of all products
listed in Table 2, 3, 4, 5.
Acknowledgements
SMI gratefully acknowledges Department of Science and Technology, (DSTꢀSERB, Project
No SB/ S1/PCꢀ107/2012 dated 10/06/2013), New Delhi, Govt. of India, University Grant
Commission (UGC, Project F. No 43ꢀ180/2014(SR) dated 25th July 2015), New Delhi, Govt.
of India and Department of Science and Technology, Govt. of West Bengal (WBꢀDST,
Project Sanction F. Noꢀ811(Sanc.)/ST/P/S&T/4Gꢀ8/2014,dated 04/01/2016) for financial
support. MMI acknowledges University Grant Commission for his Maulana Azad
fellowships (UGCꢀMANF). MH acknowledges University Grant Commission for her senior
research fellowship. SMI acknowledges DST and UGC, New Delhi, Govt of India, for
providing fund to the Dept. of Chemistry, University of Kalyani through PURSE, FIST and
SAP programme. SMI also acknowledges University of Kalyani for providing personal
research assistance grant (PRG). ASR acknowledges CSIR, New Delhi for his Research
Associateship.
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Graphical Abstract
Copper(II) incorporated functionalized polystyrene catalyzed N-arylation of
amides under solvent free condition with broad substrate scope
Md. Mominul Islam,a┼ Mita Halder,b┼ Anupam Singha Roy,*c,d Sauvik
Chatterjee,e Asim Bhaumik*e and Sk. Manirul Islam*a
aDepartment of Chemistry, University of Kalyani, Kalyani, Nadia, 741235, W.B., India.
bDepartment of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700 009, India.
cCatalytic Conversion & Processes Division, CSIR-Indian Institute of Petroleum, Dehradun
248005, India.
dEuropean Bioenergy Research Institute, Aston University, Birmingham B4 7ET, UK.
eDepartment of Material Science, Indian Association for the Cultivation of Science,
Kolkata - 700032, India.
┼These authors contributed equally to this manuscript.
A new polymer supported Cu(II) catalyst has been reported for Nꢀarylation of various amides
with aryl halides under neat reaction conditions.