The selective hydrogenolysis of C-O bonds in lignin model compounds by Pd-Ni bimetallic nanoparticles in ionic liquids

Article abstract of DOI:10.1039/c7dt02498c

β-O-4 and α-O-4 linkages can be selectively cleaved by Pd-Ni bimetallic nanoparticles in ionic liquids using hydrogen gas as the hydrogen donor under ambient pressure and neutral conditions. No hydrogenation of the benzene ring takes place in the catalytic system. An obvious improvement in activity is found compared with single nickel and palladium catalysts based on the results of experiments and characterization. After the reaction, the catalytic system still remains in the reactor by simple extraction, which can be reused without further treatment.

Full text of DOI:10.1039/c7dt02498c

View Article Online
View Journal
Dalton
Transactions
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: K. Sun, G. Lu, J.
Zhang and C. Cai, Dalton Trans., 2017, DOI: 10.1039/C7DT02498C.
This is an Accepted Manuscript, which has been through the
Volume 45 Number
1 7 January 2016 Pages 1–398
Royal Society of Chemistry peer review process and has been
accepted for publication.
Dalton
Transactions
Accepted Manuscripts are published online shortly after
An international journal of inorganic chemistry
www.rsc.org/dalton
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1477-9226
PAPER
Joseph T. Hupp, Omar K. Farha et al.
Efficient extraction of sulfate from water using
framework
a Zr-metal–organic
rsc.li/dalton

Please do not adjust margins
Dalton Transactions
Page 1 of 6
View Article Online
DOI: 10.1039/C7DT02498C
Dalton Transactions
ARTICLE
Selective hydrogenolysis of C‐O bonds in lignin model compounds
by Pd‐Ni bimetallic nanoparticles in ionic liquids
Kang‐kang Sun, Guo‐ping Lu*, Jia‐wei Zhang and Chun Cai
Received 00th January 20xx,
Accepted 00th January 20xx
The β-O-4 and ɑ-O-4 linkages can be selectively cleaved by Pd-Ni bimetallic nanoparticles in ionic liquids using hydrogen
gas as the hydrogen donor under ambient pressure and neutral conditions. No hydrogenation of benzene ring takes place in
the catalytic system. A obvious improvement in activity is found compared with single nickel and palladium catalysts based
on the results of experiments and characterization. After the reaction, the catalytic system still stays in reactor by simple
extraction, which can be reused without further treatment.
DOI: 10.1039/x0xx00000x
www.rsc.org/
4 linkages,10 however, ɑ‐O‐4 linkages fails to be cleaved, and the
hydrogenation of arenols cannot be suppressed in the presence
of H2. On the other hand, ionic liquids (ILs) as green solvents are
not only more effective at lignin dissolution than other
solvents,2i,11 but also suitable medias for the generation and
stabilisation of metal nanoparticles (MNPs),12 in which the
reaction medium with MNPs can be reused directly by simple
extraction or distillation. A few reports have developed several
metal NPs in ILs for the selective reductive cleavage of C–O and
HDO.13
Based on these results, we envisage to explore a Pd‐Ni
BMNPs in ILs for the selective hydrogenolysis of C‐O bonds.
Herein, a facile and stable Pd‐Ni BMNPs in [bmim]OTf is
introduced by which the β‐O‐4 and ɑ‐O‐4 linkages can be cleave
selectively, moreover no hydrogenation of arene occurs. To the
best of our knowledge, there is the first example on selective
hydrogenolysis of C‐O bonds by Pd‐Ni BMNPs in ILs.
Introduction
Lignin is the only large‐volume renewable polyaromatic
feedstock, which is a potential alternatives to fossil fuels for the
production of fuels and chemicals in the near future.1 However,
the current strategy including hydrolysis, reduction, oxidation
and microbe for the degradation of lignin into value‐added
products is inefficient,2 so it is typically viewed as a waste
stream in current biorefinery processes. Inspired by the
structure of lignin which is mainly bonded through several types
of Caryl‐O linkages,1,2j selective hydrogenolysis of C‐O bonds,
especially β‐O‐4 linkages has become one of the most
significant and challenging accesses for the utilization of lignin.3
Compared with other metals, nickle catalysts show excellent
selectivity in the cleavage of the Caryl‐O ether linkages.4 A series
of powerful and high‐selective nickel catalysts have been
disclosed to selective hydrogenolysis of aryl ethers.5 Meanwhile,
palladium catalysts can selective activation of the Caryl‐O bonds,6
and the cleavage of β‐O‐4 linkages via hydrogen transfer is also
achieved by these catalysts.7 Therefore, we reason that the Pd‐
Ni bimetallic nanoparticles (BMNPs) are more powerful and
higher selective catalysts for the hydrogenolysis of lignin than
single Ni and Pd catalyst, because they usually show a
combination of properties associated with two different metals
and performance superior to their monometallic counterparts
due to a phenomenon collectively referred as synergistic
effects.8
Results and discussion
The hydrogenolysis of C‐O bonds performance of Pd‐Ni
BMNPs were investigated via selecting 1a as the model
substrate (Table 1). Various Pd‐Ni BMNPs in different ILs were
prepared for the hydrogenolysis of 1a (entries 1‐9). Only
[bmim]OTf and [bsmim]OTf provided moderate yields (entries
6, 9). However the obviously aggregation of NPs was observed
during the reaction in [bsmim]OTf, so [bmim]OTf was selected
for the further studies. Other types BMNPs in [bmim]OTf were
also applied in the reaction, but no satisfactory result was
observed (entry 10‐17). The temperature was also optimized,
and 130 oC was the best option. Pd NPs results in a poor yield,
and no reaction occurred catalyzed by Ni NPs (entries 22, 23).
Moreover, a simple mixture of Pd and Ni NPs did not lead to a
obvious increase in catalytic activity (entry 24), which verified
the roles of the synergistic effects in BMNPs.
Several nickle based BMNPs have been prepared for the
cleavage of β‐O‐4 linkage,9 in which the combination of nickle
and other noble metals can obvious improve the yields and
selectivity of hydrogenolysis. More recently, our group has
designed a efficient Pd‐Ni BMNPs for the hydrogenolysis of β‐O‐
Chemical Engineering College, Nanjing University of Science & Technology,
Xiaolingwei 200, Nanjing 210094, P. R. China. E‐mail: glu@njust.edu.cn
A higher ratio of nickel in BMNPs lead to a more active
catalyst when the total loading of palladium is held constant in
Electronic Supplementary Information (ESI) available: More experimental, details,
ICP and TEM data and NMR studies. See DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1‐3 | 1
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 2 of 6
View Article Online
DOI: 10.1039/C7DT02498C
ARTICLE
Journal Name
Table 1 Optimization reaction conditions.a
yield (%)b
entry
IL
T (oC)
catalyst
2a
4a
12
2
5
16
0
4
0
0
1
2
3
4
5
6
7
[hmim]NTf2
[hmim]Br
[hmim]HSO4
[hmim]BF4
[hmim]OAc
[bmim]OTf
[bupy]BF4
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
80
120
130
160
130
130
130
130
130
130
130
130
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Fe4
Pd1Cu4
Pd1Co4
Pd1Zn4
Pd1Sn4
Ir1Ni4
25
12
13
14
0
70
7
0
72
<1
2
39
0
0
0
0
0
17
78
87
91
13
0
15
8
[pmpip]NTf2
[bsmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
[bmim]OTf
9c
2
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
<1
<1
5
0
0
0
0
0
7
1
2
9
0
0
0
3
0
Ru1Ni4
Au1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pd1Ni4
Pdd
Fig. 1 TEM images of (a) (b) freshly prepared Pd1Ni7 BMNPs in [bmim]OTf (c) (d) Pd1Ni7
BMNPs after 4 cycles. The inset images show the size distribution of Pd‐Ni BMNPs.
Nie
Pdd+Nie
Pd1Ni1
Pd1Ni2
Pd1Ni6
Pd1Ni7
Pd1Ni8
Furthermore, X‐ray photoelectron spectrum (XPS) was also
carried out to evaluate the surface composition and electronic
state of the Pd‐Ni bimetallic catalyst. The XPS results indicate
that the ratio of the surface concentration between Pd and Ni is
0.22, which is higher than the results determined by ICP‐MS
(Table S3 in ESI), so the structure of Pd‐Ni BMNPS is mixed alloy,
9
73
93
0
0, 1f, 3g
0
99, 98f, 76g
98
a Conditions: Catalyst 5 mol% (the amount of palladium in the catalyst), IL 1.0 mL,
1a 0.5 mmol, H2 1 atm, 12 h. b GC yields with dodecane as the internal standard. on the surface of which Pd mainly distributes. The hydrogen
Only products 2a, 3a and 4a was found in the reaction, so the yield of 2a is the
transfer ability of Pd is weakened due to the surrounded Ni
atoms in BMNPs, which makes great contributions to the
inhibition in hydrogenation selectivity (geometric effects).14
same as the yield of 3a. c The obviously aggregation of NPs was observed during
the reaction. d 5 mol% Pd NPs was used. e 20 mol% Ni NPs was used. f 4 mol% of
g
palladium in the catalyst was used. 3 mol% of of palladium in the catalyst was
Because nickel can be easily oxidized to oxide and hydroxide
when exposed to oxygen and moisture in air, the Ni spectral
used.
the reaction at 5 mol% (entries 20, 25‐29), and a Pd/Ni molar feature of the catalyst consists of metallic Ni as well as Ni oxide
ratio of 1/7 was found to be optimal presumably owing to the and hydroxide, which may segregate its terrace zones, thus
enhancement of hydrogen storage capacity.9 The Pd1Ni7 BMNPs preventing benzene ring coordination and hydrogenation.9c
was detected by the inductively coupled plasma mass
As illustrated in Fig. 2b, the peaks located at 335.8 eV and
spectrometry (ICP‐MS) (see ESI, Table S3), which confirmed that 340.7 eV can be assigned to Pd 3d5/2 and Pd 3d3/2, which
the Pd/Ni ratio was consistent with the designed composition confirmed the formation of the Pd‐Ni alloy in the BMNPs.15 The
of the Pd1Ni7 BMNPs. The excellent yield was also afforded other doublet at 338.3 eV and 343.2 eV is ascribed to the +2
when the amount of palladium in BMNPs could be dropped to oxidation state of Pd.8e,16 The 3d5/2 binding energy of Pd shifted
4 mol% (entry 28).
from 335.6 eV in the Pd catalysts to 335.8 eV in Pd‐Ni BMNPs
Encouraged by these remarkable results, further (see Fig. S1 in ESI), indicating electron transfer from Pd to
investigations on the morphologies of the catalyst were made. Ni9,10,17 that creates more electron‐rich Ni sites. The electron‐
Pd1Ni7 NPs were separated from [bmim]OTf by centrifugation, rich Ni center may spur the conversion from H• to H‐, which
which was suspended in ethanol, deposited on a copper grid significantly speeds up the hydrogenolysis process (electronic
coated by a carbon film and then used in transmission electron effects).9b Based on experimental and XPS results, it can be
microscopy (TEM) measurements. As shown in Fig. 1, the as purposed that Ni and Pd promote the participation of each
prepared Pd‐Ni BMNPs are well‐proportioned, anomalously other in the hydrogenolysis reaction through the formation of
spherical, and the average size of the NPs is about 1.5 nm and alloy NPs.
2.0 nm for the freshly prepared and 4 cycle‐samples,
respectively. Nevertheless, Pd‐Ni BMNPs are aggregated
obviously after reusing four times (Fig. 1c, 1d).
2 | J. Name., 2012, 00, 1‐3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Page 3 of 6
Dalton Transactions
View Article Online
DOI: 10.1039/C7DT02498C
Journal Name
ARTICLE
Entry
Ar1
Ph
Ph
Ph
Ph
Ar2
Ph
Yield (%)b
>99
1
2
3
4
5
6
7
8
2,6‐dimethylphenyl
3,5‐dimethoxyphenyl
2,6‐dimethoxyphenyl
2,6‐dimethoxyphenyl
Ph
87
98
95
58
46
73
85
4‐MeOC6H5
4‐MeOC6H5
3‐MeOC6H5
3‐MeOC6H5
2‐MeOC6H5
2,6‐dimethoxyphenyl
a Conditions: 1 0.5 mmol, Pd1Ni7 BMNPs 4 mol% (the amount of palladium in the
catalyst), [bmim]OTf 1 mL, H2 1 atm, 130 oC, 16 h. b GC yields of 2 with dodecane
as the internal standard.
Table 3 The hydrogenolyisis of ɑ‐O‐4 linkages by Pd‐Ni BMNPs in [bmim]OTf.a
Entry
Ar3
Ph
Ph
Ph
Ph
4‐MeO
3‐MeO
4‐O2N
Ar4
Ph
Yield (%)b
83
1
2
3
4
5
6
7
2,6‐dimethylphenyl
2,6‐dimethoxyphenyl
3,5‐dimethoxyphenyl
2,6‐dimethoxyphenyl
2,6‐dimethoxyphenyl
2,6‐dimethoxyphenyl
89
98
95
62c
71c
>99d,e
a Conditions: 1 0.5 mmol, Pd1Ni7 BMNPs 4 mol% (the amount of palladium in the
catalyst), [bmim]OTf 1 mL, H2 1 atm, 100 oC, 16 h. b GC yields of 6 with dodecane
as the internal standard. c 130 oC. d 80 oC. e p‐toluidine and 2,6‐dimethoxyphenol
were obtained as the final products.
Fig. 2 XPS spectrum of Pi1Ni7 BMNPs: (a) Ni 2p region (b) Pd 3d region.
With the optimized conditions in hands, a series of β‐O‐4
lignin model compounds were selected to investigate the β‐O‐4
bond cleavage in more detail (Table 2). Introducing methyl or
methoxyl group in Ar2 ring have no obvious influence in the
reaction in all cases, while a evident decrease of yield was
observed in the cases of Ar1 with methoxyl group (entries 5‐8)
owing to the increased BDE of the β‐O‐4 linkage and the yield of
undesired products
and was found in all reactions (Table 2), so the yields of
the same as the yields of . The ɑ‐O‐4 lignin model compounds
4 2, 3
(See Table S2 in ESI).18 Only products
4
2 are
3
have more reactive than the β‐O‐4 ones (Table 3), and the
hydrogenolysis can be achieved at 100 oC. The methoxyl group
on Ar1 ring can inhibit the process (entries 5, 6), while a electron‐
withdraw group (nitro group) on Ar1 ring enhance the
transformation (entry 7). In all cases, no hydrogenation product
or other byproduct was detected (Table 2 and 3). Only products
Scheme 1 Control experiments. Conditions: aryl ether 0.5 mmol, Pd1Ni7 BMNPs 4 mol%
(the amount of palladium in the catalyst), [bmim]OTf 1 mL, H2 1 atm, 130 oC, 16 h; GC
yields.
6
and
7 was found in all reactions (Table 3), so the yields of 6
are the same as the yields of
7
.
Table 2 The hydrogenolyisis of β‐O‐4 linkages by Pd‐Ni BMNPs in [bmim]OTf.a
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1‐3 | 3
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 4 of 6
View Article Online
DOI: 10.1039/C7DT02498C
Dalton Transactions
ARTICLE
Fig. 3 Proposed mechanisms for the hydrogenolysis of β‐O‐4 and ɑ‐O‐4 linkages. Pd1Ni7 BMNPs are depicted by surface for clarity.
Further experiments were also performed to investigate the the product underwent in‐flask extraction with minimum
tentative pathway for the hydrogenolysis. Aryl ethers 4a, 8‐10 amounts of an organic solvent (ethyl ether). The IL phase with
,
12 failed to be cleaved under optimized conditions (eq. 1‐4,6), BMNPs can be reused directly in the next run. The process could
and the hydrogenolysis of 11 proceeded smoothly to afford a be repeated 4 times without an obvious change in yields (Fig.
excellent yield of 3a (eq. 5). Based on these results, it can be 4). The inactivation of the catalyst may be caused by the
concluded that (1) the hydrogens at ɑ and β positions of β‐O‐4 aggregation of the NPs after each reaction (Fig. 1c,1d). The loss
ethanolaryl ethers and the HO‐substituted ɑ‐carbon are of NPs in each run may be another main reason as well.
necessary for the reaction; (2) 11 may be a intermediate of the
hydrogenolysis.7a,7c
Experimental
General
Although the detailed mechanism of this reaction remains to
be elucidated, a tentative pathway for the hydrogenolysis of C‐
O bonds by Pd‐Ni BMNPs was illustrated in Fig. 3. For the β‐O‐4
linkages, the reaction starts with a reversible dehydrogenation
All chemical reagents are obtained from commercial
suppliers and used without further purification. GC‐MS was
performed on an ISQ Trace 1300 in the electron ionization (EI)
mode. GC analyses are performed on an Agilent 7890A
instrument (Column: Agilent 19091J‐413: 30 m × 320 μm × 0.25
μm, carrier gas: H2, FID detection. Transmission electron
microscopy (TEM) images were taken using a PHILIPS Tecnai 12
microscope operating at 120 kv. X‐ray photoelectron
spectroscopy (XPS) were performed on a ESCALAB 250Xi
spectrometer, using a Al Kα X‐ray source (1350 eV of photons)
and calibrated by setting the C 1s peak to 284.80 eV. Inductively
coupled plasma mass spectrometry (ICP‐MS) was analyzed on
Optima 7300 DV. 1H NMR spectra are recorded on an AVANCE
III 500 Bruker spectrometer operating at 500 MHz in CDCl3.
Synthesis of Pd1Ni7 BMNPs in [bmim]OTf
of
1
and chemically adsorbed hydrogen on catalyst to generate
by further
intermediate A,7a,7c which can be transformed to
B
absorbing to BMNPs. According to the Horiuti‐Polanyi‐type
mechanism,19 the atomic hydrogen may insert into either the ɑ
or β position of intermediate
and C’ are yielded following inserting metal to the C‐O bond.
Reductive elimination of aryloxide and enol equivalent ( ) or
carbene (C’) lead to the final products. For the ɑ‐O‐4 linkages,
the benzylic C‐H can be activated by the catalyst to form . Then,
metal inserts to the C‐O bond to produce . The hydorgenolysis
products are obtained though the reductive elimination of
The [bmim]OTf may also enhance the reaction by the non‐
covalent interaction,20 which may play a similar role as the
electron‐withdraw groups in Ar1 ring to enhance the acidic of
B. Therefore, two intermediates C
C
E
F
F.
Pd(OAc)2 (4.5 mg, 0.02 mmol) and Ni(OAc)2 (24.7 mg, 0.14
mmol) in 500 μL methanol was stirred at room temperature for
20 min. Then the solution was added into [bmim]OTf (1.0 mL).
The reaction mixture was stirred at room temperature. After 10
min, methanol were then removed under reduced pressure (0.1
methylene of 5 (See ESI, Fig. S2).
Finally, studies were also conducted to assess the potential
for recycling of the reaction medium, and the reaction of 1a was
selected as the model reaction. After completion of reaction,
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1‐3 | 4
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 5 of 6
View Article Online
DOI: 10.1039/C7DT02498C
Journal Name
ARTICLE
bar) at 35 °C for 30 min using a rotary evaporator, followed by enhancement owing to the synergistic effects based on
the addition of 60 μL of NaBH4 (12.0 mg, 0.32 mmol) solution in experimental and characterization results. Tentative
water (The operations was carried out under N2 atmosphere), mechanisms for the hydrogenolysis of
β‐O‐4 and ɑ‐O‐4
which was prepared immediately before use. The formation of linkagesby the catalyst are also proposed according to the
a deep black solution indicated the formation of metal results of control experiments. Moreover, the ionic liquid with
nanoparticles, the mixture was further stirred for 2 h.
General procedures for the catalytic reactions
Pd‐Ni BMNPs remains in the reactor after simple extraction, and
can be reused several times without further treatment.
Lignin model compounds 0.5 mmol was added into the
catalytic system ([bmim]OTf with Pd1Ni7 BMNPs) equipped with
a magnetic stirrer, then the H2 was induced (H2 was
Acknowledgements
We gratefully acknowledge the Natural Science Foundation
of China (21402093) and Jiangsu (BK20140776) and Chinese
120
100
80
60
40
20
0
Post‐doctoral
Science
Foundation
(2016T90465,
2015M571761) for financial support. This work is a project
funded by the Priority Academic Program development of
Jiangsu Higher Education Institution.
Notes and references
1
(a) A. J. Ragauskas, G. T. Beckham, M. J. Biddy, R. Chandra, F.
Chen, M. F. Davis, B. H. Davison, R. A. Dixon, P. Gilna, M. Keller,
P. Langan, A. K. Naskar, J. N. Saddler, T. J. Tschaplinski, G. A.
Tuskan and C. E. Wyman, Science, 2014, 344. 709; (b) C. O.
0
1
2
3
4
Tuck, E. P
érez, I. T. Horváth, R. A. Sheldon and M. Poliakoff,
Run
Science, 2012, 337, 695; (c) K. Sanderson, Nature, 2011, 474
,
S12; (d) C. Xu, R. A. D. Arancon, J. Labidi and R. Luque, Chem.
Soc. Rev., 2014, 43, 7485.
Fig.4 Catalyst recycling studies
2
(a) J. C. Serrano‐Ruiz and J. A. Dumesic, Energy Environ. Sci.,
provided using a hydrogen balloon. Removing the air from the
reactorwith Ar before this operation). Subsequently, the reactor was
placed into a preheated oil bath at 100 oC or 130 oC and stirred for
16 h. After the reaction completion, the reactor was quenched to
ambient temperature using cooling water, Then, organic
components are extracted with diethyl ether repeatedly until no
more product present in the bottom IL residue (determined by 1H
NMR). The obtained residue was analyzed by GC/MS or GC.
2011,
Hensen, ChemSusChem, 2014,
P. K. Agrawal and C. W. Jones, ChemSusChem, 2012,
4
, 83; (b) X. Huang, T. I. Kor
á
nyi, M. D. Boot and E. J. M.
, 2276; (c) W. Xu, S. J. Miller,
, 667;
7
5
(d) D. R. Vardon, M. A. Franden, C. W. Johnson, E. M. Karp, M.
T. Guarnieri, J. G. Linger, M. J. Salm, T. J. Strathmann and G. T.
Beckham, Energy Environ. Sci., 2015,
Bruijnincx and B. M. Weckhuysen, Nat. Chem., 2014,
(f) G. Fuchs, M. Boll and J. Heider, Nat. Rev. Micro., 2011,
8
, 617; (e) P. C. A.
6
, 1035;
9
,
803; (g) M. P. Pandey and C. S. Kim, Chem. Eng. Technol., 2011,
34, 29; (h) M. Besson, P. Gallezot and C. Pinel, Chem. Rev.,
2014, 114, 1827; (i) G. Chatel and R. D. Rogers, ACS Sustain.
Chem. Eng., 2014, 2, 322; (j) S. K. Hanson and R. T. Baker, Acc.
Chem. Res., 2015, 48, 2037.
Recycling catalytic system
After reaction completion, the mixture was then extracted
with diethyl ether (3×1 mL). The organic layer was collected and
removed in vacuo to afford the crude products, which was
analyzed by GC/MS or GC. The IL phase sperated by extraction
could be reused in the next run directly. To the recovered IL
phase with Pd1Ni7 BMNPs, 1a 0.5 mmol was added. Then, the
H2 was induced (H2 was provided using a hydrogen balloon.
Removing the air from the reactor with Ar was required before
this operation) at room temperature. Subsequently, the reactor
3
4
(a) N. Luo, M. Wang, H. Li, J. Zhang, T. Hou, H. Chen, X. Zhang,
J. Lu and F. Wang, ACS Catal., 2017, 4571; (b) S.‐H. Li, S. Liu, J.
C. Colmenares and Y.‐J. Xu, Green Chem., 2016, 18, 594; (c) Q.
Song, F. Wang and J. Xu, Chem. Commun., 2012, 48, 7019; (d)
M. Tobisu and N. Chatani, ChemCatChem, 2011, 3, 1410; (e) Y.
Ren, M. Yan, J. Wang, Z. C. Zhang and K. Yao, Angew. Chem.
Int. Ed., 2013, 52, 12674; (f) J. M. Nichols, L. M. Bishop, R. G.
Bergman and J. A. Ellman, J. Am. Chem. Soc., 2010, 132, 12554;
(g) M. Zaheer and R. Kempe, ACS Catal., 2015, 5, 1675.
o
o
(a) Z.‐C. Cao and Z.‐J. Shi, J. Am. Chem. Soc., 2017, 139, 6546.
was placed into a preheated oil bath at 100 C or 130 C and
stirred for 16 h. The extraction cycle was then repeated for the
separation of crude products and catalytic system.
(b) B. M. Rosen, K. W. Quasdorf, D. A. Wilson, N. Zhang, A.‐M.
Resmerita, N. K. Garg and V. Percec, Chem. Rev., 2010, 111
,
1346. (c) H. Yue, L. Guo, H. H. Liao, Y. Cai, C. Zhu and M.
Rueping, Angew. Chem. Int. Ed., 2017, 56, 4282; (d) K. Muto,
J. Yamaguchi, D. G. Musaev and K. Itami, Nat. Commun., 2015,
Conclusions
6
, 7508; (e) M. D. Karkas, B. S. Matsuura, T. M. Monos, G.
Magallanes and C. R. J. Stephenson, Org. Biomol. Chem., 2016,
14 1853; (f) B. Sawatlon, T. Wititsuwannakul, Y.
In summary, we have prepared a stable Pd‐Ni BMNPs in
[bmim]OTf, which proves to be an efficient catalyst for the
hydrogenolysis of the
selectivity. Compared with single nickle and palladium catalysts,
the Pd‐Ni bimetallic catalyst has superior activity
,
Tantirungrotechai and P. Surawatanawong, Dalton Trans.,
2014, 43, 18123.
β‐O‐4 and ɑ‐O‐4 linkages with high
5
(a) A. G. Sergeev and J. F. Hartwig, Science, 2011, 332, 439; (b)
F. Gao, J. D. Webb and J. F. Hartwig, Angew. Chem. Int. Ed.,
2016, 55, 1474; (c) A. G. Sergeev, J. D. Webb and J. F. Hartwig,
a
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1‐3 | 5
Please do not adjust margins

Please do not adjust margins
Dalton Transactions
Page 6 of 6
View Article Online
DOI: 10.1039/C7DT02498C
ARTICLE
Journal Name
J. Am. Chem. Soc., 2012, 134, 20226; (d) J. He, C. Zhao and J. 20 (a) R. Kumar, Saima, A. Shard, N. H. Andhare, Richa and A. K.
A. Lercher, J. Am. Chem. Soc., 2012, 134, 20768; (e) X. Cui, H.
Yuan, K. Junge, C. Topf, M. Beller and F. Shi, Green Chem.,
Sinha, Angew. Chem. Int. Ed., 2015, 54, 828; (b) X. Zhang, G.‐
p. Lu and C. Cai, Green Chem., 2016, 18, 5580; (c) Z.‐b. Xu, G.‐
p. Lu and C. Cai, Org. Biomol. Chem., 2017, 15, 2804.
2017, 19, 305; (f) M. Zaheer, J. Hermannsd
örfer, W. P.
Kretschmer, G. Motz and R. Kempe, ChemCatChem, 2014,
6
,
,
91; (g) Q. Song, F. Wang and J. Xu, Chem. Commun., 2012, 48
7019.
6
7
(a) T. Ben Halima, J. K. Vandavasi, M. Shkoor and S. G.
Newman, ACS Catal., 2017,
7, 2176; (b) X. Cui, K. Junge and M.
Beller, ACS Catal., 2016, , 7834. (c) T. Ben Halima, W. Zhang,
6
I. Yalaoui, X. Hong, Y.‐F. Yang, K. N. Houk and S. G. Newman, J.
Am. Chem. Soc., 2017, 139, 1311.
(a) M. V. Galkin, C. Dahlstrand and J. S. M. Samec,
ChemSusChem, 2015, 8, 2187; (b) X. Zhou, J. Mitra and T. B.
Rauchfuss, ChemSusChem, 2014,
X. Zhang, A. Heyden and F. Wang, ACS Catal., 2016,
(d) F. Gao, J. D. Webb, H. Sorek, D. E. Wemmer and J. F.
Hartwig, ACS Catal., 2016, , 7385; (e) M. V. Galkin, S.
Sawadjoon, V. Rohde, M. Dawange and J. S. M. Samec,
ChemCatChem, 2014, , 179.
(a) S. De, J. Zhang, R. Luque and N. Yan, Energy Environ. Sci.,
2016, , 3314; (b) C. J. Serpell, J. Cookson, D. Ozkaya and P. D.
Beer, Nat. Chem., 2011, , 478; (c) Z. Wei, J. Sun, Y. Li, A. K.
7
, 1623; (c) J. Lu, M. Wang,
6
, 5589;
6
6
8
9
9
3
Datye and Y. Wang, Chem. Soc. Rev., 2012, 41, 7994; (d) J. G.
Dickinson and P. E. Savage, ACS Catal., 2014, 4, 2605; (e) J.‐w.
Zhang, G.‐p. Lu, and C. Cai, Green Chem., 2017, 19, 2535; (f) J.‐
w. Zhang, G.‐p. Lu and C. Cai, Catal. Commun., 2016, 84, 25;
(g) Y.‐B. Huang, L. Yan, M.‐Y. Chen, Q.‐X. Guo and Y. Fu, Green
Chem., 2015, 17, 3010.
(a) J. Zhang, H. Asakura, J. van Rijn, J. Yang, P. Duchesne, B.
Zhang, X. Chen, P. Zhang, M. Saeys and N. Yan, Green Chem.,
2014, 16, 2432; (b) J. Zhang, J. Teo, X. Chen, H. Asakura, T.
Tanaka, K. Teramura and N. Yan, ACS Catal., 2014, 4, 1574; (c)
J. Zhang, M. Ibrahim, V. Collière, H. Asakura, T. Tanaka, K.
Teramura, K. Philippot and N. Yan, J. Mol. Catal. A‐Chem.,
2016, 422, 188; (d) C. Zhang, J. Lu, X. Zhang, K. MacArthur, M.
Heggen, H. Li and F. Wang, Green Chem., 2016, 18, 6545; (d)
H. Konnerth, J. Zhang, D. Ma, M. H. G. Prechtl and N. Yan,
Chem. Eng. Sci., 2015, 123, 155.
10 J.‐w. Zhang, Y. Cai, G.‐p. Lu and C. Cai, Green Chem., 2016, 18
,
6229.
11 J. Zakzeski, P. C. A. Bruijnincx, A. L. Jongerius and B. M.
Weckhuysen, Chem. Rev., 2010, 110, 3552; (b) A. Stark,
Energy Environ. Sci., 2011, 4, 19; (c) E. C. Achinivu, R. M.
Howard, G. Li, H. Gracz and W. A. Henderson, Green Chem.,
2014, 16, 1114; (d) S. Zhang, J. Sun, X. Zhang, J. Xin, Q. Miao
and J. Wang, Chem. Soc. Rev., 2014, 43, 7838; (e) Y.‐X. An, N.
Li, H. Wu, W.‐Y. Lou and M.‐H. Zong, ACS Sustain. Chem. Eng.,
2015, 3, 2951.
12 (a) J. Dupont and J. D. Scholten, Chem. Soc. Rev., 2010, 39
,
1780; (b) H. Konnerth and M. H. G. Prechtl, Chem. Commun.,
2016, 52, 9129; (c) J. Hu, Q. Yang, L. Yang, Z. Zhang, B. Su, Z.
Bao, Q. Ren, H. Xing and S. Dai, ACS Catal., 2015, 6724. (d) Q.
Zhang, S. Zhang and Y. Deng, Green Chem., 2011, 13, 2619.
13 (a) L. Chen, J. Xin, L. Ni, H. Dong, D. Yan, X. Lu and S. Zhang,
Green Chem., 2016, 18, 2341; (b) N. Yan, Y. Yuan, R. Dykeman,
Y. Kou and P. J. Dyson, Angew. Chem. Int. Ed.,
2010, 49, 5549.
14 J. Zhang and C. Zhao, ACS Catal., 2016, , 4512.
6
15 M. A. Arellano‐González, A. C. Texier, L. Lartundo‐Rojas and I.
González, J. Electrochem. Soc. 2015, 162, E223.
16 J. Xia, Y. Fu, G. He, X. Sun and X. Wang, Applied Catal. B‐
Environ., 2017, 200, 39.
17 A. S. Camacho, I. Martín‐García, C. Contreras‐Celedón, L.
Chacón‐García and F. Alonso, Catal. Sci. Technol., 2017, 7
,
2262.
18 S. Kim, S. C. Chmely, M. R. Nimlos, Y. J. Bomble, T. D. Foust, R.
S. Paton and G. T. Beckham, J. Phys. Chem. Lett., 2011,
19 F. Zaera, Phys. Chem. Chem. Phys., 2013, 15, 11988.
2, 2846.
6 | J. Name., 2012, 00, 1‐3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins