Base-Free Suzuki–Miyaura Coupling Reaction Using Palladium(II) Supported Catalyst in Water

Article abstract of DOI:10.1007/s10562-019-02723-9

Abstract: The carbon–carbon bond formation via Suzuki–Miyaura reaction was performed in water as green solvent. Pd(OAc)₂(PPh₃)₂ supported on magnesium hydroxide and cerium carbonate hydroxide composite was prepared and characterized by various techniques. The cross-coupling reaction of aryl halides carried out in water using mild conditions. The effects of temperature, solvents, the amount of catalyst and leaving groups were studied to find the optimization conditions for cross-coupling reaction. Various aryl halides were smoothly transformed into the biaryls in good yields. In addition, the catalyst also exhibited stability and catalytic performance in the cross-coupling of aryl halides. Graphical Abstract: [Figure not available: see fulltext.] A new approach is developed for carbon–carbon bond formation via Suzuki–Miyaura reaction.₂ Pd(OAc)₂(PPh₃)₂?supported on mixed magnesium hydroxide and cerium carbonate hydroxide were prepared and characterized by XRD, XPS, SEM–EDX techniques. The cross-coupling reaction of aryl halides can be carried out in water and under mild conditions (80 °C).

Full text of DOI:10.1007/s10562-019-02723-9

Catalysis Letters
https://doi.org/10.1007/s10562-019-02723-9
Base-Free Suzuki–Miyaura Coupling Reaction Using Palladium(II)
Supported Catalyst in Water
Ravi Tomar1 · Nidhi Singh1 · Neeraj Kumar1 · Vartika Tomar1 · Ramesh Chandra1,2
Received: 9 November 2018 / Accepted: 20 February 2019
© Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract
The carbon–carbon bond formation via Suzuki–Miyaura reaction was performed in water as green solvent. Pd(OAc)2(PPh3)2
supported on magnesium hydroxide and cerium carbonate hydroxide composite was prepared and characterized by various
techniques. The cross-coupling reaction of aryl halides carried out in water using mild conditions. The effects of temperature,
solvents, the amount of catalyst and leaving groups were studied to find the optimization conditions for cross-coupling reac-
tion. Various aryl halides were smoothly transformed into the biaryls in good yields. In addition, the catalyst also exhibited
stability and catalytic performance in the cross-coupling of aryl halides.
Graphical Abstract
A new approach is developed for carbon–carbon bond formation via Suzuki–Miyaura reaction.2 Pd(OAc)2(PPh3)2 supported
on mixed magnesium hydroxide and cerium carbonate hydroxide were prepared and characterized by XRD, XPS, SEM–
EDX techniques. The cross-coupling reaction of aryl halides can be carried out in water and under mild conditions (80 °C).
Keywords Base-free · Suzuki–Miyaura coupling · Water as solvent · Pd(II) catalyzed · Magnesium hydroxide and cerium
carbonate hydroxide composite
1 Introduction
The carbon–carbon bond formation is a very interesting
Electronic supplementary material The online version of this
article (https://doi.org/10.1007/s10562-019-02723-9) contains
supplementary material, which is available to authorized users.
topic in organic chemistry. The Suzuki–Miyaura reaction is
one of the important reactions in C–C cross coupling reac-
tion [1]. Symmetrical and unsymmetrical biaryl products
of an arylboronic acid and aryl halides have good applica-
tions in various areas like preparation of materials, natural
products, bioactive molecules, herbicides, antifungal, anti-
inflammatory, antirheumatic, antitumor, and antihyperten-
sive agents and conducting polymers [2].
* Ravi Tomar
ravitomar451@gmail.com
* Ramesh Chandra
rameshchandragroup@gmail.com
1
Drug Discovery & Development Laboratory, Department
Therefore, Suzuki–Miyaura reaction has attracted
researchers for development of new methodologies and
catalytic routes. On the other hand, it usually proceeds by
of Chemistry, University of Delhi, Delhi 110007, India
2
Dr. B. R. Ambedkar Center for Biomedical Research,
University of Delhi, Delhi 110007, India
Vol.:(0123456789)
1 3

R. Tomar et al.
using phosphine-based palladium catalysts, palladium nano-
particles [3–5], microwave technology [6–11], nucleophilic
carbene ligands [12–15], ionic liquids [16–21], palladium
supported on various species like carbon [22–25], silica
[26], zeolites [27], metal–organic frameworks [28], and so
on [29, 30]. Choudary and co-workers [31] had reported
Suzuki coupling reaction using a nano-palladium catalyst
with KF as the base (Scheme 1a). Zhang et al. [32] had also
reported phosphine-free Suzuki–Miyaura reaction in water
with sodium carbonate, while Biao Jiang et al. [33] showed
ligand-free Suzuki–Miyaura reaction in water using trieth-
ylamine as base. Recently, Kohki Ebitani and co-workers
[34] demonstrated Suzuki–Miyaura coupling using hydrotal-
cite-supported palladium with potassium carbonate. These
methods have used homogeneous bases and various solvents
which increase the cost of production. Therefore, any meth-
odology or catalytic route which eliminates the homogenous
base and can be performed in the greener solvent, then cost
of production will be low.
protocols need some modifications using water as solvents,
heterogeneous catalyst, base-free condition.
Recently, magnesium hydroxide and cerium carbon-
ate hydroxide composite eliminated the homogenous base
for Henry reaction [49]. We have an ongoing research on
the development of a new solid base catalyst for base-
free reaction at our laboratory [50–53]. In this study,
we have extended the scope of solid base catalyst for
greener approach for base-free Suzuki–Miyaura reaction.
From green and substantial chemistry points of view, for
Suzuki–Miyaura reaction, we have designed our basic aim
for the reaction to develop a new catalytic system which
employs (i) heterogeneous Pd-salt catalyst, (ii) without
any homogenous base, and (iii) without air or oxygen. To
realize this aim, Pd(OAc)2(PPh3)2 supported on mixed
magnesium hydroxide and cerium carbonate hydroxide
Pd(OAc)2(PPh3)2/MgCe-HDC was synthesized [54], which
acted as efficient catalyst for the cross-coupling of aryl hal-
ides and phenylboronic acids to obtain the desired symmet-
ric or unsymmetric biaryls at 80 °C under base-free aqueous
condition. To the best of our knowledge, it is the first report
about the application of MgCe-HDC for Suzuki–Miyaura
reaction.
Palladium(II) salts supported catalysts have been
reported many times for different organic transformations
like oxidation of alcohols [35, 36], Heck reaction [37–40],
Suzuki–Miyaura reaction [41], Sonogashira reaction [42],
and so on [43]. Generally, Suzuki–Miyura reaction was
reported in DMF [10], aq. DMF [44], Toluene–water [45],
aq. EtOH [46], dioxane [47], dioxane–water [31], and so on
[32, 34, 48]. For green approaches, Suzuki–Miyaura reaction
The catalyst was characterized by X-ray diffraction (XRD)
patterns (see Figure S1, in the Supporting Information)
confirming the phase of magnesium hydroxide and cerium
carbonate hydroxide in Pd(II) supported catalyst. Figure S3
iv. Palladium-catalyzed, ligang-free Suzuki reaction in water
K. B. Sharpless and Biao Jiang et al.
i. Suzuki coupling reaction of chloroarenes using LDH-Pd0
B. M. Choudhary et al.
B(OH)2
X
B(OH)2
Cl
LDH-Pd0
Pd(OAc)2, Et3N
Air, rt, water
R1
R2
R2
+
R1
+
R2
R1
KF, 100 °C
Dioxane/water
10 h
R1
R2
v. Suzuki-Miyaura coupling reaction using hydrotalcite-supported
palladium catalyst Kohki Ebitani et al.
ii. Phosphine-Free palladium acetate catalyzed Suzuki reaction in
water Y. Zhang et al.
B(OH)2
X
B(OH)2
X
PdCl2/HT
Surfactant
Pd(OAc)2
R1
R1
R2
+
+
R1
R2
R1
K2CO3, 40 °C
EtOH,1.5 h
Na2CO3, 50 °C
water-PEG, 10 h
iii. Suzuki coupling reaction of chloroarenes using gold
nanoparticles R. Guo et al.
vi. Present work
B(OH)2
R2
X
B(OH)2
Cl
R2
R1
Au catalyst
R1
R2
R1
+
H2O, 80 °C
Pd(OAc)2(PPh3)2/
MgCe-HDC
NaOH, 80 °C
water, 4 h
R1
R2
Base-free
35 examples
Yields of up to 90 %
R
1 = electrowithdrawing,
electrodonating
X = Br, I
Scheme 1 Previous reports versus present work
1 3

Base-Free Suzuki–Miyaura Coupling Reaction Using Palladium(II) Supported Catalyst in Water
(Supporting Information) showed the XRD pattern of cata-
lyst after 5th run. SEM–EDX was also performed and shown
in Figure S2(i) (see Supporting Information). Figure S2(i)
represents: (a) low magnified SEM images of the MgCe-
HDC (b) high magnified SEM images of the MgCe-HDC,
(c) high magnified SEM image of Pd(OAc)2(PPh3)2/MgCe-
HDC and (d–i) elemental mapping images of six elements:
(d) C K edge, (e) Ce L edge, (f) Mg K edge, (g) O K edge,
(h) P K edge, (i) Pd L edge. Figure S2(ii) showed the SEM
image of catalyst after 5th run. We can conclude that pal-
ladium (II) species distributed in uniform patterns does not
alter the porosity of material after loading of Pd(II) species.
Figure S4 (see Supporting Information) represents the XPS
spectrum of Pd(OAc)2(PPh3)2/MgCe-HDC and MgCe-HDC.
As shown in Figure S4 (Supporting Information), the signals
centered at about 332.2 and 337.4 eV for supported Pd(II) on
MgCe-HDC as assigned to Pd 3d 5/2 and Pd 3d 3/2 regions,
respectively, indicative of the existence of Pd(II) species
[55]. The binding energy values 130, 282.3, 286.3 and 530
correspond to P 2p, C 1s(C–C), C 1s(C–O) and O 1s spec-
trum [56–59]. Figure S10 (see Supporting Information) rep-
resents the XPS spectrum of Pd(OAc)2(PPh3)2/MgCe-HDC
after 5th Run. The TGA (Figure S9, Supporting Information)
analysis shows a two-step weight loss in the material. The
first weight loss (7.13 wt% and 0.2638 mg) corresponds to
the decomposition of Mg(OH)2 to MgO and water, whereas
the second weight loss (14.51 wt% and 0.4985 mg) indicates
a loss of water and carbon dioxide from CeCO3OH. The pH
of catalyst in water was 10.44.
The aryl chloride has shown less reactivity towards
phenylboronic acid in this simple catalytic system at
80 °C without other additives in pure water as a solvent
(Table 1, entry 4). Thus, Pd(OAc)2(PPh3)2/MgCe-HDC can
be used as cheap and greener catalyst for aryl halide in the
Suzuki–Miyura reaction in water.
Inspired by these stimulating results, various reaction
parameters, including the amount of catalyst, temperature,
and solvents, were screened broadly order to optimize the
reaction condition for the coupling of boronic acid and
aryl bromide. For solvents optimization, we have carried
out three solvents i.e. DMF, DMSO, and water in present
work (Table 2, entries 1, 2 and 4). The aryl bromide showed
better yield with phenylboronic acid in water as compared
to other solvents. Next, the amount of catalyst for cross-
coupling reaction was investigated (Table 1). When the cata-
lyst was increased to 100 mg, biaryl was obtained with an
isolated yield of 55.5% after reaction for 2 h. by increasing
the amount of catalyst to 200 and 300 mg, only 38.4 and
32.9% yield of biaryl were obtained (Table 2, entries 5 and
6). Even with a very low amount of catalyst (50 mg), a 20%
of the yield of biaryl was still obtained (Table 2, entry 50).
Effect of temperature was observed from room temperature
to 373 K (Table 2). The yield first increased till 353 K; after
353 K, the yields gradually decreased till 373 K. At 343 and
353 K, aryl bromide was coupled with phenylboronic acid
in quantitative yield (Table 2, entries 4 and 9).
With the optimal conditions in hand, the reaction condi-
tions were then applied to the coupling of a variety of the
substrates (Table 3). The electron-rich and electron-with-
drawing groups containing boronic acids were coupled with
Pd(OAc)2(PPh3)2/MgCe-HDC was employed and com-
pared with a variety of partners, including aryl halides
(iodo-, chloro-, fluoro-) and aryl tosylate for phenylboronic
acid in the Suzuki–Miyaura reaction (Table 1). The aryl
iodide was found to react smoothly with phenylboronic acid
while aryl bromide and aryl tosylate have shown moderate
reactive behavior (Table 1, entries 1–3).
Table 2 Optimization of the reaction conditions for Suzuki reaction
B(OH)2
Br
Pd(OAc)2(PPh3)2/MgCe-HDC
+
Entry
Solvent
Catalyst (mg)
Tempara-
Yielda (%)
ture (K)
1
2
3
4
5
6
7
8
DMF
DMSO
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
100
100
50
353
353
353
353
353
353
rt
333
343
363
373
33.7
25.9
20.8
55.8
38.4
32.9
36.3
38.9
45.4
25.9
23.3
Table 1 Performance
of
different
leaving
groups
B(OH)2
X
Pd(OAc)2(PPh3)2/MgCe-HDC
H2O, 2 h, 80 °C
100
200
300
100
100
100
100
100
+
Entry
Leaving group (X)
Yielda (%)
1
2
3
4
I
90.8
55.5
24.6
19.5
Br
OTs
Cl
9
10
11
Reactions conditions: aryl-X (0.5 mmol), phenyl boronic acid
(0.6 mmol), H2O (4 mL), catalyst (100 mg), 80 °C, 2 h
Reactions conditions: aryl-X (0.5 mmol), phenyl boronic acid
(0.6 mmol), solvent (4 mL), 2 h
aIsolated yield
aIsolated yield
1 3

R. Tomar et al.
Table 3 Suzuki–Miyaura reaction of aryl halide derivatives and boronic acids
B(OH)2
X
R2
Pd(OAc)2(PPh3)2/MgCe-HDC
H2O, 80 °C
R1
R2
+
R1
Me
CN
Me
OMe
5, X = Br, 43.4 %
10, X = I, 45.6 %
4, X = Br, 47.6 %
9, X = I, 83.2%
3, X = Br, 48.7 %
8, X = I, 49.9 %
1, X = Br, 55.8 % 2, X = Br, 21.2 %
6, X = I, 90.8 % 7, X = I, 60.5 %
Me
Me
CN
OMe
CHO
11, X = Br, 47.3 % 12, X = Br, 43.4 %
CN
CHO
13, X = Br, 84.6 %
CHO
14, X = Br, 42.8 %
CHO
CHO
15, X = Br, 87.6 %
Me
Me
OMe
CHO
CHO
CHO
19, X = Br, 81.5 %
Me
CHO
CHO
20, X = Br, 59.4 %
18, X = Br, 45.9 %
Me
16, X = Br, 34.0 % 17, X = Br, 13.51 %
CN
OMe
NH2
NH2
21, X = Br, 47.3 % 22, X = Br, 19.6 %
NH2
NH2
NH2
25, X = Br, 75.3 %
24, X = Br, 29.5 %
23, X = Br, 22.9 %
Me
Me
CN
OMe
H2N
H2N
28, X = Br, 78.6 %
H2N
H2N
H2N
30, X = Br, 45.2 %
29, X = Br, 41.5 %
Me
26, X = Br, 81.6 % 27, X = Br, 41.18 %
Me
CN
OMe
OMe
31, X = Br, 54.3 % 32, X = Br, 23.9 %
OMe
OMe
OMe
OMe
35, X = Br, 56.0 %
34, X = Br, 40.4 %
33, X = Br, 67.6 %
Reactions conditions: aryl-X (0.5 mmol), boronic acid derivatives (0.6 mmol), H2O (4 mL), catalyst (100 mg), 80 °C, 2 h
Isolated yield
different aryl halides derivatives using Pd(OAc)2(PPh3)2/
MgCe-HDC in water at 80 °C for 2 h. The iodobenzene
was coupled with phenylboronic acid, 4-cyanoboronic
acid, 4-methylboronic acid, 4-methoxyboronic acid, and
2-Methylboronic acid (Table 3, entries 1–5). The iodo-
benzene seemed to be less reactive towards 4-methyl, and
2-methoxy with yields of 49.9% and 45.6% as compared to
other boronic acids. The bromobenzene was tolerated well
1 3

Base-Free Suzuki–Miyaura Coupling Reaction Using Palladium(II) Supported Catalyst in Water
and engaged in reactions with these boronic acids except
4-cyanoborononic acid. Electron-rich group at para-position
encouraged the reaction with 2-bromobenzaldehyde while
–CN, –H, and –Me showed yield range of 42.0–47.3%.
3-Bromobenzaldehyde also coupled with boronic acids, out
of them cross-coupling 2-methylboronic acid gave a good
yield.
Ce(NO3)3·6H2O (10 mmol) and water (100 mL) were added
in another 200 mL beaker salts were let dissolve completely
and dropped into the 200 mL of beaker while pH was kept
to be 10. Gel was obtained and aged for 4 h at 338 K, filtered
and washed with water (~4 L), thoroughly up to neutral pH.
The obtained semi-solid was dried in an oven overnight at
373 K then solid was crushed to convert it to powder form.
4-Cyanoboronic acid was less compatible with the opti-
mal reaction conditions. 2-bromoaniline gave moderate
yield with phenylboronic acid. On the other hand, it gave
effective yield with 4-methoxyboronic acid while it gave
comparatively low yield with cyano-, methyl- group contain-
ing boronic acids. However, surprisingly these results were
opposite when 4-bromoaniline coupled with boronic acids.
Phenylboronic acid and 4-methylboronic acid gave good
yield with 4-bromoaniline. 3-Methoxyaniline also coupled
with five boronic acids, except 4-cynoboronic acid other all
have moderate yields. In these cases, however, biphenyl was
formed as a byproduct from self- coupling of phenyl boronic
acid as confirmed by 1H-NMR (Table 3, entries 11, 21, and
31).
2.2 Preparation of Supported Pd(OAc)2(PPh3)2
Over Mixed Magnesium Hydroxide and Cerium
Carbonate Hydroxide Composite
Pd(OAc)2(PPh3)2 supported on mixed magnesium hydroxide
and cerium carbonate hydroxide (Pd(OAc)2(PPh3)2/MgCe-
HDC) were prepared according to literature with a modi-
fied procedure [54] (synthesis of Pd(OAc)2 on hydrotalcite).
A typical preparation procedure is as follows: 112 mg of
Pd(OAc)2 and 216 mg of PPh3 were dissolved in 10 mL of
toluene. 1 g of magnesium hydroxide and cerium carbonate
hydroxide were added to this solution and the mixture was
stirred at 80 °C for 1 h. After the reaction, the solution was
filtered and washed with toluene (40 mL). The residue was
dried at 100 °C for 30 min and finally grained to obtain the
desired Pd(OAc)2(PPh3)2/MgCe-HDC.
To examine the scope of recycling of the heterogene-
ous catalyst, the catalyst was used 5 times with no loss in
catalytic activity as shown in Figure S11 (see Supporting
Information). The catalytic activity, however, decreased after
the 2nd run, which could either be due to temporary poison-
ing by organic impurities or loss in recovery of the catalyst
material.
2.3 General Procedure for Suzuki Reaction
A typical procedure for Suzuki reaction is as follows: aryl
halide (0.5 mmol) was weighed in 25 mL round bottom flask
containing boronic acids (0.6 mmol), and Pd(OAc)2(PPh3)2/
MgCe-HDC (100 mg). The reactants and catalyst were dis-
persed in water (4 mL), the RB was mounted on an oil bath
at 353 K and the mixture was stirred for 2 h. The reaction
was monitored by thin layer chromatography (TLC). After
completion of the reaction, the catalyst was separated by
filtration. Then the solution was extracted with ethyl acetate
and brine solution. The organic phase was dried over anhy-
drous Na2SO4 and concentrated under vacuum. The crude
product was purified by column chromatography on silica
gel to afford pure product. The pure product was analyzed
using 1H- and 13C-NMR techniques and compared with lit-
erature NMR data.
In conclusion, we developed a simple, efficient pro-
cedure for the Suzuki–Miyaura cross-coupling in water.
Pd(OAc)2(PPh3)2/MgCe-HDC catalyst was prepared and
investigated in the synthesis of symmetrical or unsymmet-
rical biaryls under the base-free condition without using
any promoter. Furthermore, it can acquire good to excellent
yields (up to 90.8%) with a wide substrate scope (35 exam-
ples). This methodology can be extended to the synthesis of
nitrogen, oxygen-based heterobiaryls. Further applications
of these base-free systems in other transformations are cur-
rently under examination in our laboratory.
2 Experimental Section
2.1 Preparation of Mixed Magnesium Hydroxide
and Cerium Carbonate Hydroxide
2.4 General Procedure for Reuse of the Catalyst
First, run of the Suzuki reaction catalyzed by
Pd(OAc)2(PPh3)2/MgCe-HDC was performed by the above-
described procedure. Recovered catalyst was washed with
toluene (20 mL) and water (20 mL). Afterwards, the catalyst
was dried at 100 °C for 30 min and the obtained catalyst was
ready for reuse.
A typical preparation procedure for mixed magnesium
hydroxide and cerium carbonate hydroxide, using our pre-
vious method [49], is as follows: Na2CO3·10H2O (30 mmol,
8.6 g), NaOH (70 mmol, 2.8 g) and water (60 mL) were
taken into a 200 mL beaker. Mg(NO3)2·6H2O (30 mmol),
1 3

R. Tomar et al.
29. Schroeter F, Soellner J, Strassner T (2017) ACS Catal
7:3004–3009
Acknowledgements The present work was supported by the SERB
(DST) and the University of Delhi. We thank USIC (University of
Delhi, Delhi, India) for providing the NMR, IR instrument facilities
and Japan Advanced Institute of Science and Technology (Japan) for
SEM–EDS, XPS, XRD instruments facilities. RT is thankful to SERB
(DST) senior research fellowship and also thankful to JAIST for JASSO
fellowship during Japan stay. This study was funded by Science and
Engineering Research Board (EMR/2016/002976).
30. Chen X, Engle KM, Wang DH, Jin-Quan Y (2009) Angew Chem
Int Ed 48:5094–5115
31. Choudary BM, Madhi S, Chowdari NS, Kantam ML, Sreedhar B
(2002) J Am Chem Soc 124:14127–14136
32. Liu L, Zhang Y, Wang Y (2005) J Org Chem 70:6122–6125
33. Liang Q, Xing P, Huang Z, Dong J, Sharpless KB, Li X, Jiang B
(2015) Org Lett 17:1942–1945
34. Choudhary H, Jia J, Nishimura S, Ebitani K (2017) Asian J Org
Chem 6:274–277
References
35. Kakiuchi N, Maeda Y, Nishimura T, Uemura S (2001) J Org Chem
66:6620–6625
36. Kakiuchi N, Nishimura T, Inoue M, Uemura S (2001) Bull Chem
Soc Jpn 74:165–172
1. Suzuki A (2011) Angew Chem Int Ed 50:6723–6733
2. Horton DA, Bourne GT, Smythe ML (2003) Chem Rev
103:893–930
37. Ping EW, Venkatasubbaiah K, Fuller TF, Jones CW (2010) Top
Catal 53:1048–1054
3. Kogan V, Aizenshtat Z, Popovitz-biro R, Neumann R (2002) Org
Lett 4:3529–3532
38. Inamoto K, Kawasaki J, Hiroya K, Kondo Y, Doi T (2012) Chem
Commun 48:4332–4334
4. Thathagar MB, Beckers J, Rothenberg G (2002) J Am Chem Soc
124:11858–11859
39. Duan H, Li M, Zhang G, Gallagher JR, Huang Z, Sun Y, Luo Z,
Chen H, Miller JT, Zou R et al (2015) ACS Catal 5:3752–3759
40. Mangala K, Sinija PS, Sreekumar K (2015) J Mol Catal A Chem
407:87–92
5. Reetz MT, Westermann E (2000) Angew Chem Int Ed 39:165–168
6. Leadbeater NE, Marco M (2002) Org Lett 4:2973–2976
7. Wu TYH, Schultz PG, Ding S (2003) Org Lett 5:3587–3590
8. Kabalka GW, Pagni RM, Wang L, Namboodiri V, Hair CM (2000)
Green Chem 2:120–122
41. Yılmaz N, Baran T, Baran A, Menteş (2017) Appl Catal A Gen
531:36–44
42. Sharma KK, Biradar AV, Das S, Asefa T (2011) Eur J Inorg Chem
2011:3174–3182
9. Elazab HA, Moussa S, Siamaki AR, Gupton BF, El-Shall MS
(2017) Catal Lett 147:1510–1522
43. Opanasenko M, Štěpnička P, Čejka J (2014) RSC Adv
4:65137–65162
10. Ramírez-Rave S, Morales-Morales D, Grévy J-M (2017) Inorg
Chim Acta 462:249–255
44. Liu C, Ni Q, Bao F, Qiu J (2011) Green Chem 13:1260–1266
45. Jiang X, Sclafani J, Prasad K, Repic O, Blacklock TJ (2007) Org
Process Res Dev 11:2005–2008
11. Akiyamaa T, Taniguchib T, Saitoc N, Doib R, Honmad T,
Tamenorid Y, Ohkie Y, Takahashie N, Fujiokaa H, Sato Y et al
(2017) Green Chem 19:3357–3369
46. Li Y, Hong XM, Collard DM, El-Sayed MA (2000) Org Lett
2:2385–2388
12. Herrmann WA, Reisinger C-P, Spiegler M (1998) J Organomet
Chem 557:93–96
47. Grasa GA, Hillier AC, Nolan SP (2001) Org Lett 3:1077–1080
48. Paul S, Islam MM, Islam SM (2015) RSC Adv 5:42193–42221
49. Tomar R, Singh N, Rathee G, Kumar N, Tomar V, Chandra R
(2017) Asian J Org Chem 6:1728–1732
13. Navarro O, Nolan SPSPN (2003)
125:16194–16195
J Am Chem Soc
14. Xiong Z, Wang N, Dai M, Li A, Chen J, Yang Z (2004) Org Lett
6:3337–3340
50. Tomar R, Rathee G, Chandra I, Kumar N, Tomar V (2018) Chem-
istrySelect 3:1645–1649
15. Asensio Revert JMM, Gomez-Sal P, Andrés R, de Jesús E (2017)
Dalton Trans. https://doi.org/10.1039/C7DT00643H
16. Revell JD, Ganesan A (2002) Org Lett 4:803–805
17. Mathews CJ, Smith PJ, Welton T (2000) Chem Commun
14:1249–1250
51. Tomar R, Sharma J, Nishimura S, Ebitani K (2016) Chem Lett
45:843–845
52. Arya K, Tomar R (2015) Res Chem Intermed 41:3389–3400
53. Arya K, Tomar R, Rawat DS (2014) Med Chem Res 23:896–904
54. Mora M, Jiménez-Sanchidrián C, Ruiz JR (2006) J Colloid Inter-
face Sci 302:568–575
18. Patil JD, Korade SN, Patil SA, Gaikawad DS, POre DM (2015)
RSC Adv. https://doi.org/10.1039/C5RA17186E
19. Keesara S, Babu GN, Pal S (2017) Appl Organometal Chem. https
://doi.org/10.1002/aoc.3778
55. Nefedov VI, Salyn YV, Moiseev II, Sadovskii AP, Berenbljum AS,
Knizhnik AG, Mund SL (1979) Inorg Chim Acta 35:343–344
56. Hussain N, Borah A, Darabdhara G, Gogoi P, Azhagan VK,
Shelke MV, Das MR (2015) New J Chem 39:6631–6641
57. Velauthamurty K, Higgins SJ, Rajapakse RMG, Bacsa J,
van Zalinge H, Nichols RJ, Haiss W (2009) J Mater Chem
19:1850–1858
20. Wang M, Yuan X, Li H, Ren L, Sun Z, Hou Y, Chu W (2015)
Catal Commun 58:154–157
21. Han Y, Lin C, Meng Q, Dai F, Sykes AG, Berry MT, May PS
(2014) Inorg Chem 53:5494–5501
22. Chen X, Hou Y, Wang H, Cao Y, He J (2008) J Phys Chem C
112:8172–8176
58. Chen B, Li J, Dai W, Wang L, Gao S (2014) Green Chem
16:3328–3334
23. Cornelio B, Rance Ga, Laronze-Cochard M, Fontana A, Sapi J,
Khlobystov AN (2013) J Mater Chem A 1:8737–8744
24. Ray C, Dutta S, Sahoo R, Roy A, Negishi Y, Pal T (2016) Chem
Asian J 11:1588–1596
59. Ning Y, Yang Z, Zhao H (1996) Platin Met Rev 40:80–87
25. Modak A, Bhaumik A (2016) J Mol Catal A Chem 425:147–156
26. Zhi J, Song D, Li Z, Lei X, Hu A (2011) Chem Commun
47:10707–10709
Publisher’s Note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations.
27. Sharma M, Sharma M, Hazarika A, Satyanarayana L, Karunakar
GV, Bania KK (2017) Mol Catal 432:210–219
28. Choudhary H, Nishimura S, Ebitani K (2014) J Mater Chem A
2:18687–18696
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