Palladium-Loaded Cucurbit[7]uril-Modified Iron Oxide Nanoparticles for C?C Cross-Coupling Reactions

Article abstract of DOI:10.1002/chem.201705082

Cucurbit[7]uril modified iron oxide nanoparticles (CB[7]NPs) were loaded with palladium to form nano-catalysts (Pd@CB[7]NPs) that, with microwave heating, catalysed Suzuki–Miyaura, Sonogashira, and Mizoroki–Heck cross-coupling reactions. Reactions were run in environmentally benign 1:1 ethanol/water solvent under convenient aerobic conditions. In a preliminary screening, conversions and yields were uniformly high with turn over frequencies (TOF) ranging from 64 to 7360 h^?1. The nano-catalysts could be recovered with a magnet and reused several times (6 times for Suzuki–Miayura reaction) without loss of activity.

Full text of DOI:10.1002/chem.201705082

A Journal of
Accepted Article
Title: Palladium-loaded cucurbit[7]uril-modified iron-oxide nanoparticles
for C-C cross-coupling reactions
Authors: Erwann Guenin, Farah Benyettou Benyettou, Hassan
Traboulsi, Laurence Motte Motte, Javed Mazer, Renu
Pasricha Pasricha, John-Carl Olsen Olsen, and Ali Trabolsi
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To be cited as: Chem. Eur. J. 10.1002/chem.201705082
Link to VoR: http://dx.doi.org/10.1002/chem.201705082
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Palladium-loaded cucurbit[7]uril-modified iron oxide
nanoparticles for C-C cross-coupling reactions
Farah Benyettou,[b] Laurence Motte,[c] Hassan Traboulsi,[d] Javed Mazher,[e] Renu Pasricha,[b] John-Carl
Olsen,[f] Ali Trabolsi*[b] and Erwan Guenin* [a,c]
magnetic recovery that avoids filtration and centrifugation.[6]
Abstract: Cucurbit[7]uril modified iron oxide nanoparticles
(CB[7]NPs) were loaded with palladium to form nano-catalysts
Such an approach is cost-effective for cross coupling reactions
that rely on expensive metal catalysts such as palladium,
platinum, or ruthenium. Another benefit of using
nanoparticles, especially those composed of iron oxide, as a
(Pd@CB[7]NPs) that, with microwave heating, catalysed Suzuki-
Miyaura, Sonogashira, and Mizoroki-Heck cross coupling reactions.
All reactions were run in environmentally benign 1/1 ethanol/water
solvent under convenient aerobic conditions. In
a preliminary
catalyst support is synergism. It has been found that
interaction between palladium and Brønsted basic sites on the
surface of iron oxide nanoparticles can enhance catalytic
activity in Heck and Suzuki reactions,[7] whereas acidic support
materials have been found to diminish the catalytic activity of
the metal.[7-8] Phosphine, salen, and N-heterocyclic carbene
ligands have been used to attach palladium to particles for the
catalysis of Suzuki-Miyaura, Mizoroki-Heck, and Sonogashira
cross-coupling reactions.[9] Recently we proposed an
alternative strategy for palladium attachment that relies on a
proline-based ligand and allows for the preparation of an
efficient, recyclable Pd-supported nano-catalyst for the
Suzuki-Miyaura reaction in water and other aerobic media.[10]
Cucurbituril (CB[n]) macrocycles have also been shown to
function as palladium chelating ligands. Equipped with guest
recognition properties and the ability to bind cations to their
carbonyl-lined rims, CB[n] macrocycles,[11] and especially the
water-soluble CB[7],[12] have recently been used to construct
nanomaterial-based supramolecular assemblies that catalyze
organometallic reactions.[13] For example, nanocapsules
coated with polymerized CB[6][14] have been used as
stabilizers of Pd-based nanoparticles that catalyze the Suzuki-
Miyaura reaction[15] (though the capsules and catalyst were
not magnetically recycled). Recently, we reported the
synthesis of CB[7]-coated magnetic iron-oxide nanoparticles
(CB[7]NPs) for biomedical applications.[16] Here, we describe
adsorbing Pd(II) to CB[7]NPs to form recyclable nanoparticles
(Pd@CB[7]NPs) that catalyze Suzuki-Miyaura, Sonogashira
and Mizoroki-Heck reactions. We hypothesized that CB[7]
cavity would favor the reaction between organic species in
aqueous media, acting as a nano-reactor at the surface of the
particles.
screening, all conversions and yields were uniformly high with turn
over frequencies (TOF) ranging from 64 to 7360 h-1. The nano-
catalysts could be recovered with a magnet and reused several times
(6 times for Suzuki Miayura reaction) without loss of activity.
More than 90% of multi-step industrial chemical processes
involve catalysis in at least one step.[1] Development of new,
catalysts that make these processes less costly,
environmentally benign, and more energy efficient is a
primary goal of chemical research. In industry, heterogeneous
catalysis tends to be favored over homogeneous catalysis
because heterogeneous catalysts are easier to recycle.[2] In the
last two decades, nanomaterial-based catalysts with high
surface-to-volume ratio and highly active surface atoms have
been developed and shown to be comparable in activity and
selectivity to homogeneous catalysts.[3] Effective systems in
which the nanomaterial core (as opposed to surface) contains
catalytically active components have also been reported.[4]
Among the various nanomaterials used as solid supports,
magnetic iron oxide nanoparticles (NPs) have emerged as a
particularly convenient option[5] because they allow for simple
[a]
Dr. E. Guenin
Sorbonne Universités, Université de Technologie de Compiègne,
Integrated Transformations of Renewable Matter Laboratory (EA
TIMR 4297 UTC-ESCOM), rue du Dr Schweitzer, 60200 Compiègne,
France. E-mail: erwann.guenin@utc.fr
[b]
[c]
Dr. F. Benyettou, Dr. R. Pasricha, Pr. A. Trabolsi
New York University Abu Dhabi, United Arab Emirates
E-mail: at105@nyu.edu
Pr. L. Motte
Inserm, U1148, Laboratory for Vascular Translational Science, UFR
SMBH, Université Paris 13, Sorbonne Paris Cité, 74 avenue M.
Cachin, 93017 Bobigny, France.
The surface of the NPs was modified with CB[7] by mixing bare
iron-oxide NPs with an excess of CB[7] in water at pH = 2 and
50 °C under microwave irradiation for one hour.[16] Palladium
was adsorbed onto the surface of CB[7]NPs by the addition of
palladium acetate, Pd(AcO)2, to CB[7]NPs in MeOH/H2O
solvent (Scheme 1).[10]
[d]
[e]
[f]
Pr. Hassan Traboulsi
Chemistry Department, College of Sciences, King Faisal University –
Al Ahsa, 31982, Kingdom of Saudi Arabia.
Dr. J. Mazher
Physics Department, College of Sciences, King Faisal University-Al
Ahsa, 31982, Kingdom of Saudi Arabia.
Pr. J.-C. Olsen
Department of Chemistry, RC Box 270216, University of Rochester,
Rochester, NY, 14627, United States of America
Supporting information for this article is given via a link at the end of
the document.
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On the other hand, the 1s peak of carbonyl oxygen is more
intense in the spectrum of Pd@CB[7]NPs than in the spectrum
of CB[7]NPs (compare Figures S10E and S10F). This result is
likely due to the presence of acetate counter ions on the
surface of the Pd@CB[7]NPs.
The TEM image of CB[7]NPs in Figure S12A shows almost
spherical nanoparticles with sizes ranging from 8 to 12 nm.
Upon adsorption of Pd(II) to the particles, size and morphology
remain unaffected, but dark regions on the surface of the
particles appear by TEM. We performed elemental mapping
on both CB[7]NP and Pd@CB[7]NP samples to determine the
nature of these dark regions. We found that CB[7]NPs are
composed of iron and oxygen and, as expected, show no trace
of Pd (Figure S12). The clear outline around the clustered
CB[7]NPs that are visible in STEM images (Figure S12B)
indicate the presence of CB[7] macrocycles on the surface of
the particles. Elemental mapping of Pd@CB[7]NPs (Figure S15)
indicates the iron and oxygen composition and also provides
clear evidence for the presence of Pd(0). Pd(0) particles are
also clearly visible as bright spots in STEM-HADF images
(Figure S13), owing to the high molecular weight of Pd. We
examined lattice planes in order to identify the oxidation state
of the palladium detected. High resolution images of CB[7]NPs
(Figures S12 C and D) exhibit the interplanar spacing (2.54 Å)
that matches with the d-spacing value of (2 2 0) plane of
maghemite. Images of Pd@CB[7]NPs (Figures S15C and D)
exhibit two different plane spacings of 2.2 Å and 2.5 Å which
are characteristic of the (1 1 1) and (2 2 0) planes of Pd(0) and
γ-Fe2O3, respectively. The spacings were analyzed using IFFT
on the highlighted areas. The minimal, scattered presence of
Pd(0) apparent in the images is consistent with the XPS
analysis.
The crystalline structure of the cores of CB[7]NPs and
Pd@CB[7]NPs were confirmed (Figure S16) by powder X-ray
diffraction (PXRD). The reflections in the XRD patterns can be
easily indexed with the inverse spinel structure of maghemite
(ICDD PDF039-1346). The similarity of the data for the two
sample types indicates that the core structure of NPs is
unaffected by Pd(II) treatment. Extra peaks in the pattern
associated with the Pd@CB[7]NP sample correspond to Pd0
(ICDD 98-004-1517) and indicate, as did XPS and TEM analyses,
the presence of palladium nanoparticles in small quantity
(Figure S17).
Scheme 1. Schematic representation of the loading of Pd(II) onto CB[7]NPs
(top) and the catalytic activity of the metal-loaded particles, Pd@CB[7]NPs,
(bottom).
Averages of 450 (± 50) Pd(II) ions per NP and 16 (± 2) Pd(II) ions
per macrocycle were deduced by electron dispersive X-ray
(EDX) analysis (Figure S7). The palladium was strongly bound:
neither several water washes of the particles nor heating of
the particles to 50 °C in water/ethanol for several hours
significantly diminished the amount Pd(II) adsorbed.
The FTIR spectrum of CB[7]NPs features the characteristic 600
cm−1 Fe–O absorption band of iron oxide, as well as separated
C=O bands of CB[7] at 1733 cm−1 and 1636 cm−1 that
correspond to uncomplexed and particle-bound carbonyls,
respectively (Figure S9). The FTIR spectrum of CB[7]NPs
treated with Pd(II) (Figure S9) shows that the chemical
constitution of CB[7]NPs is preserved in the presence of Pd, as
evidenced by the characteristic Fe–O band and CB[7]
absorptions at 1731 and 1632 cm-1, and the fact that no new
peaks are present.
X-ray photoelectron spectroscopy (XPS) was used to analyse
the elemental composition of the surface of the Pd@CB[7]NPs
(Figure S10). Figure S10 displays the Fe 2p XPS spectra
characteristic of CB[7]NPs (Figure S10A) and Pd@CB[7]NPs
(Figure S10B). In these, the 2P3/2 and 2P1/2 peaks are centered
at 710.8 and 724.5 eV, respectively. The Fe 2p3/2 peaks are
associated with satellite peaks. The satellite of the Fe 2p3/2
peak of Fe2O3 is located approximately 8 eV to the right.[17] The
high resolution XPS spectrum presented in Figure S11 shows
intense peaks that correspond to 3d5/2 (337.4 eV) and Pd 3d3/2
(342.7 eV) absorptions of Pd(II).[10] Dissolved Pd(II) ions are
known to bind to the electron-rich oxygens of the carbonyl-
lined portals of surface-attached CB[7].[18] Less intense 3d5/2
and 3d3/2 absorptions at 335.1 eV and 340.9 eV, respectively,
reflect the presence of a small amount of Pd(0).[19] The 1s peak
of nitrogen does not appear in the spectrum of Pd@CB[7]NPs
(Figures S10C and S10D). This signal suppression might be a
consequence of Pd ions and neutral atoms being located
inside and around the macrocycles on the surface of the NPs.
After establishing the presence of Pd(II) on the CB[7]NPs, the
magnetic properties of Pd@CB[7]NPs were determined in the
solid state using
a
magnetic reader.[20] Strong
superparamagnetic signals (4.9 x 108 M.U.)[20] predicted strong
attraction to a magnet and convenient catalyst recycling, a
significant practical advantage.
The obtained Pd@CB[7]NPs were stable for 30 minutes in a
1/1 ethanol/water mixture but subsequently precipitated.
Because of this relative lack of stability in solution,
Pd@CB[7]NPs were evaluated as catalysts in vigorously stirred
water/ethanol solvent mixtures. From a practical standpoint,
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this aggregation was an advantage that facilitated catalyst a cumulative TON of 5760. On the seventh cycle, conversion
recovery and recycling. dropped rather abruptly to 65% (Table 1, entry 8). This
The ability of Pd@CB[7]NPs to act as nano-catalyst for C-C decrease may have been due to deactivation of the palladium
cross-coupling was evaluated in Suzuki-Miyaura, Sonogashira, that was caused by partial discharge of the palladium salt from
and Mizoroki-Heck reactions under microwave irradiation.
Also, although inert atmosphere is a usual requirement for
the macrocycles or formation of palladium oxide. Another
control reaction was run in the presence of 0.1 mol %
these reactions,[21] we were able to run them successfully palladium in the form Pd@CB[7]NPs. However, after the usual
under aerobic conditions, which represents another major 30 minutes of heating at 80
°C, the catalyst particles and
practical advantage. product were removed from the reaction medium and fresh
Suzuki-Miyaura couplings of 4-tolylboronic acid (0.22 mM) and aryl iodide and boronic acid were added. When this partially
4-iodonitrobenzene (0.20 mM) were attempted in vigorously reconstituted mixture was subjected to the same reaction
stirred 1/1 water/ethanol solvent that was maintained at 80 conditions, conversion was less than 5%, indicating that during
°C under microwave irradiation for 30 minutes (Scheme 2). We the initial reaction the nanoparticles had leaked a small
first performed control experiments without palladium and
amount of palladium during the initial reaction and/or that
without CB[7]NPs (Table 1, entry 1), as well as with only less than 100% of the Pd@CB[7]NPs had been recovered by
CB[7]NPs that lacked surface-adsorbed palladium (Table 1, the magnet. Finally, we also evaluated the catalytic efficiency
entry 2). In both cases, no product was detected, which of a mixture of free (unrecoverable) Pd(OAc)2 and CB[7]. With
confirmed that the reaction does not occur to any appreciable these reagents, conversion was only 60%. No Pd NPs were
extent without catalyst and that CB[7]NPs alone do not
catalyze the reaction. In contrast, near quantitative yields of
formed during this reaction, which leads us to conclude that,
beyond allowing for easy recovery, immobilization of Pd onto
product were isolated when Pd@CB[7]NPs were used (Table magnetic CB[7]NPs increases palladium's catalytic activity
1, entries 2-6).
under the given conditions, a result that may be linked to the
synergetic effect already described in the literature.[7]
To test the effectiveness of the Pd@CB[7]NPs in other typical,
palladium-catalyzed reactions, we ran Sonogashira and Mizoroki-
Heck cross couplings. Prior to catalyst evaluation, we performed
the same type of control experiments as described above for the
Suzuki-Miyaura reaction. None of these controls yielded product.
We found that, with Pd@CB[7]NPs, Sonogashira reactions could be
carried out without the usual addition of copper and phosphine
ligands.[21] We also found that, like the Suzuki-Miyaura reactions,
both Sonogashira and Mizoroki-Heck reactions could be performed
under aerobic conditions. A representative Sonogashira reaction
(Scheme 2) involved the condensation of phenylacetylene (0.22
mM) and 4-iodonitrobenzene (0.20 mM) using K2CO3 as a base in a
1/1 water/ethanol solvent mixture heated to 80°C by MW
irradiation for 6 h. Only a small amount of the nano-catalyst (1.25
mg, 0.25 mol%) was necessary to achieve 100% conversion of the
starting materials and 94% isolated yield (TON = 384, TOF = 64 h-1)
of the cross-coupled product. No side-products were detected (see
NMR analysis in the SI). In general, conversions and yields with MW
heating were similar to those obtained when the reaction was
heated in an oil bath. Decreasing the reaction time or the amount
of nano-catalyst resulted in incomplete conversion. Total
conversion was reached for up to three consecutive cycles
(cumulative TON = 1152) before the Pd@CB[7]NPs began to lose
activity and yields decreased (see SI). This decrease is consistent
with the longer reaction time that was required. The greater
exposure to aerobic atmosphere and the prolonged heating during
the 6 h cycles of Sonogashira reaction decreased the catalyst's
activity more per cycle than during the shorter 30 minute Suzuki-
Miyaura reaction cycles. When replacing iodonitrobenzene by
bromo or chloro substrates, we observed the same trend as we saw
with the Suzuki-Miyaura reaction: good conversion with 4-
bromonitrobenzene (82%) and lower conversion with 4-
chloronitrobenzene (20%).
Scheme 2. Suzuki-Miyaura C-C cross-coupling catalysed by Pd@CB[7]NPs.
We then reduced the amount of palladium (0.025 mol % Pd)
which resulted in 100% conversion, 92% isolated yield, turn
over number (TON) of 3680 and turn over frequency (TOF) of
7360 h-1. It is worth noting that 0.025 mol % represents only
250 ppm of Pd and, in these reactions, required the addition
of only 125 µg of Pd@CB[7]NPs, an extremely small amount of
heterogeneous catalyst. Furthermore, no side-products from
1
dehalogenation or homocoupling were detected by H NMR
analysis in any of the crude reaction mixtures.
In order to evaluate the effectiveness of our catalyst for
coupling other halogenated benzenes, we tested 4-bromo and
4-chloronitrobenzene. Conversion with the former (97%, TOF
= 1920 h-1) was similar to that obtained with 4-iodobenzene,
whereas conversion with the latter was low (20%, TOF = 400
h-1), though it was expected to be so due to the lower
reactivity of chlorine. In terms of TOF, our results compare
favorably to those obtained in Suzuki-Miyaura reactions
involving previously reported Pd-based catalysts (see S.I.). To
test the recyclability of the Pd@CB[7]NPs, we ran reactions
with 0.1 mol % Pd (0.5 mg Pd@CB[7]NPs). We were able to
recover the catalyst from these reactions with a small magnet,
and the recovered catalyst could be used up to six more times
with no decrease in conversion (Table 1, entry 7) representing
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similar reactions run in aqueous media (see S.I.). Unlike
dissolved Pd(OAc)2, Pd@CB[7]NPs were recyclable and could
be used several times without losing activity, in particular, in
the Suzuki-Miyaura and Sonogashira reactions. These initial
results demonstrate that Pd@CB[7]NPs are an efficient,
economical, and environmentally benign catalyst system with
potential for application in the pharmaceutical industry and
Scheme 3. Sonogashira C-C cross-coupling catalyzed by Pd@CB[7]NPs.
As a representative Mizoroki-Heck reaction, we condensed the broader chemical industry.
methyl methacrylate (0.88 mM) with 4-iodonitrobenzene
(0.20 mM) for 2 h at 100 °C under MW irradiation (Scheme 3).
Again, low catalyst loading (0.25 mol % Pd) was used. The
Pd
Quantity
mol %
Conversion %a
(isolated
yield)
Entry
X
Conditions
reaction was performed in 1/1 water/ethanol under aerobic
conditions but with NEt3, rather than K2CO3, as base to avoid
saponification of the ester or transesterification with ethanol.
Under these conditions, conversion, yield, TON and TOF were
95%, 90%, 360 and 180 h-1, respectively. Replacing iodine
substitutents with bromine or chlorine affected the results
more dramatically than in the case of Suzuki-Miyaura or
Sonogashira reactions. Conversion with 4-bromonitrobenzene
decreased to 40%, and no product was observed with 4-
chloronitrobenzene under these conditions.
1
2
3
4
5
6
I
I
I
I
I
I
No catalyst
CB[7]NPs
0
0
traces
traces
Pd@CB[7]NPs
Pd@CB[7]NPs
Pd@CB[7]NPs
1
100 (98)
100 (95)
100 (96)
100 (92)
0.25
0.10
0.025
0.10
Pd@CB[7]NPs
Pd@CB[7]NPs
6th cycle
7
8
I
I
100
65
Pd@CB[7]NPs
7th cycle
0.10
9
Br
Cl
Pd@CB[7]NPs
Pd@CB[7]NPs
0.10
0.10
97
20
Scheme 4. Mizoroki-Heck C-C cross-coupling catalyzed by Pd@CB[7]NPs.
10
Table 1. Evaluation of Suzuki-Miyaura reaction conditions. a Conversion was
measured by 1H NMR spectroscopy.
Conclusions
In summary, an initial screening demonstrated that
Pd@CB[7]NPs are effective nano-catalysts for Suzuki-Miyaura,
Sonogashira, and Mizoroki-Heck reactions under conditions
that are convenient and green. Under an air atmosphere and
in an environmentally benign 1/1 ethanol/water solvent
mixture, conversions were high, especially in Suzuki-Miyaura
and Sonogashira reactions involving iodo and bromo
electrophiles. As anticipated, yields were lower when
chlorinated substrates were used.[22] Further investigations
will be conducted to improve yields with these more
challenging substrates. None of the reactions required the
addition of ligands such as phosphines, and the Sonogashira
reaction did not require copper. The Sonogashira and
Mizoroki-Heck reactions could be run at lower temperatures,
with lower catalyst loadings, and for shorter reaction times
than those required when Pd-based catalysts are used in
organic solvents.[6b, 9a, 23] Palladium concentration in the ppm
range was effective for the Suzuki-Miyaura reaction,
representing, to our knowledge, the lowest effective catalyst
loading yet achieved with a CB[7]/Pd nano-catalyst assembly:
20 to 200 times less palladium than used in similar, previously
reported work.[15a] Also, in terms of TOF, the results were
generally high compared to those reported in the literature for
Acknowledgements
This research was sponsored by the European Union, the
Région Haut de France, the Ecole Supérieur de Chimie
Organique et Minérale (ESCOM) and Université de
Technologie de Compiègne (UTC) through FEDER funding of
the chair: “Green Chemistry and Processes”. The research was
also sponsored by New York University Abu Dhabi (NYUAD)
and carried out by using the NYUAD Core Technology Platform
resources. F.B., R.P. and A.T. thank NYUAD for their generous
support.
Conflicts of interest
There are no conflicts to declare.
Keywords: Magnetic nano-catalyst • Suzuki-Miyaura, Mizoroki-
Heck, and Sonogashira cross-coupling reactions • Cucurbit[7]uril
• Palladium
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10.1002/chem.201705082
Chemistry - A European Journal
COMMUNICATION
[12]
[13]
D. Shetty, J. K. Khedkar, K. M. Park, K. Kim, Chem. Soc. Rev.
2015 44, 8747-8761.
References
a) S. Gurbuz, M. Idris, D. Tuncel, Org. Biomol. Chem. 2015 13,
330-347; b) V. Montes-Garcia, J. Pérez-Juste, I. Pastoriza-Santos,
L. M. Liz-Marzàn, Chem. Eur. J. 2014, 20, 10874-10883.
G. Yun, Z. Hassan, J. Lee, J. Kim, N.-S. Lee, N. H. Kim, K. Baek, I.
Hwang, C. G. Park, K. Kim, Angew. Chem. Int. Ed. 2014, 53,
6414-6418.
a) M. Cao, J. Lin, H. Yang, R. Cao, Chem. Commun. 2010, 46,
5088-5090; b) G. Yun, Z. Hassan, J. Lee, J. Kim, N. S. Lee, N. H.
Kim, K. Baek, I. Hwang, C. G. Park, K. Kim, Angew. Chem. Int. Ed.
2014 53, 6414-6418.
F. Benyettou, I. Milosevic, Y. Lalatonne, F. Warmont, R. Assah, J.-
C. Olsen, M. Jouaid, L. Motte, C. Platas-Iglesias, A. Trabolsi, J.
Mater. Chem. B 2013, 1, 5076-5082.
T. Yamashita, P. Hayes, Appl. Surface Sci. 2008, 254, 2441-2449.
R. Chakrabarty, P. S. Mukherjee, P. J. Stang, Chem. Rev. 2011,
111, 6810-6918.
A. Hassine, S. Sebti, A. Solhy, M. Zahouily, C. Len, M. N. Hedhili,
A. Fihri, Appl. Cat. A: Gen. 2013, 450, 13-18.
F. Benyettou, K. Nchimi-Nono, M. Jouiad, Y. Lalatonne, I.
Milosevic, L. Motte, J.-C. Olsen, N. i. Saleh, A. Trabolsi, Chem.
Eur. J. 2015, 21, 4607-4613.
R. Chinchilla, C. Najera, Chem. Soc. Rev. 2011, 40, 5084-5121.
N. Miyaura, A. Suzuki, Chem. Rev. 1995, 95, 2457-2483.
F. Dehghani Firuzabadi, Z. Asadi, F. Panahi, RSC Adv. 2016, 6,
101061-101070.
[1]
I. Chorkendorff, J. W. Niemantsverdriet, in Concepts of Modern
Catalysis and Kinetics, Wiley-VCH Verlag GmbH & Co. KGaA,
2005, pp. 1-21.
[14]
[15]
[2]
[3]
I. Fechete, Y. Wang, J. C. Védrine, Cat. Today 2012, 189, 2-27.
a) L. L. Chng, N. Erathodiyil, J. Y. Ying, Acc. Chem. Res. 2013 46,
1825-1837; b) N. Sharma, H. Ojha, A. Bharadwaj, D. P. Pathak, R.
K. Sharma, RSC Adv. 2015, 5, 53381-53403.
[4]
[5]
a) Y. Lin, J. Ren, X. Qu, Acc. Chem. Res. 2014, 47, 1097-1105; b)
B. Ni, X. Wang, Adv. Sci. 2015, 2, n/a-n/a.
[16]
a) M. B. Gawande, R. Luque, R. Zboril, ChemCatChem 2014, 6,
3312-3313; b) V. Polshettiwar, R. Luque, A. Fihri, H. Zhu, M.
Bouhrara, J.-M. Basset, Chem. Rev. 2011, 111, 3036-3075; c) S.
Shylesh, V. Schunemann, W. R. Thiel, Angew. Chem. Int. Ed.
2010, 49, 3428-3459.
[17]
[18]
[6]
a) R. S. Varma, Sustain. Chem. Proc. 2014, 2, 11; b) D. Wang, D.
Astruc, Chem. Rev. 2014, 114, 6949-6985; c) L. M. Rossi, N. J. S.
Costa, F. P. Silva, R. Wojcieszak, Green Chem. 2014, 16, 2906-
2933; d) R. K. Sharma, S. Dutta, S. Sharma, R. Zboril, R. S.
Varma, M. B. Gawande, Green Chem. 2016, 18, 3184-3209.
J. Shi, Chem. Rev. 2013, 113, 2139-2181.
a) B. Karimi, D. Elhamifar, J. H. Clark, A. J. Hunt, Chem. Eur. J.
2010, 16, 8047-8053; b) A. Cwik, Z. Hell, F. Figueras, Adv. Synth.
Cat. 2006, 348, 523-530.
[19]
[20]
[7]
[8]
[21]
[22]
[23]
[9]
a) B. Karimi, F. Mansouri, H. M. Mirzaei, ChemCatChem 2015, 7,
1736-1789; b) S. Paul, M. M. Islam, S. M. Islam, RSC Adv. 2015,
5, 42193-42221.
[10]
[11]
E. Nehlig, B. Waggeh, N. Millot, Y. Lalatonne, L. Motte, E. Guenin,
Dalton Trans. 2015, 44, 501-505.
K. I. Assaf, W. M. Nau, Chem. Soc. Rev. 2015, 44, 394-418.
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10.1002/chem.201705082
Chemistry - A European Journal
COMMUNICATION
COMMUNICATION
Cucurbit[7]uril modified iron-oxide
nanoparticles (CB[7]NPs) were loaded
with palladium to form nano-catalysts
(Pd@CB[7]NPs) that, with microwave
heating, catalysed Suzuki-Miyaura,
Sonogashira, and Mizoroki-Heck
cross coupling reactions.
Farah Benyettou, Laurence Motte,
Hassan Traboulsi, Javed Mazher, Renu
Pasricha, John-Carl Olsen, Ali Trabolsi*
and Erwan Guenin*
Page No. – Page No.
Title
This article is protected by copyright. All rights reserved.