Palladium-metalated porous organic polymers as recyclable catalysts for chemoselective decarbonylation of aldehydes

Article abstract of DOI:10.1039/c8cc03109f

A novel palladium nanoparticle (NP)-metalated porous organic ligand (Pd NPs/POL-xantphos) has been prepared for the chemoselective decarbonylation of aldehydes. This heterogenous catalyst not only has excellent catalytic activity and chemoselectivity, but also holds high activity after 10 runs of reuse. The effective usage of this method is demonstrated through the synthesis of biofuels such as furfuryl alcohol (FFA) via the highly chemoselective decarbonylation of biomass-derived 5-hydroxy-methylfurfural (HMF) with a TON up to 1540. More importantly, 9-fluorenone could be obtained in one step through the decarbonylation of 2-bromobenzaldehyde by using this heterogeneous catalyst.

Full text of DOI:10.1039/c8cc03109f

View Article Online
View Journal
ChemComm
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: W. Li, C. Li, Y. Li,
H. Tang, H. Wang, Y. Pan and Y. Ding, Chem. Commun., 2018, DOI: 10.1039/C8CC03109F.
This is an Accepted Manuscript, which has been through the
Volume 52 Number
1 4 January 2016 Pages 1–216
Royal Society of Chemistry peer review process and has been
accepted for publication.
ChemComm
Accepted Manuscripts are published online shortly after
Chemical Communications
www.rsc.org/chemcomm
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 1359-7345
COMMUNICATION
Marilyn M. Olmstead, Alan L. Balch, Josep M. Poblet, Luis Echegoyenet al.
Reactivity differences of Sc3N@C2n (2n 68 and 80). Synthesis of the
first methanofullerene derivatives of Sc N@D5h-C80
=
3
rsc.li/chemcomm

Please do not adjust margins
ChemComm
Page 1 of 4
View Article Online
DOI: 10.1039/C8CC03109F
Journal Name
COMMUNICATION
Palladium-Metalated Porous Organic Polymers as Recyclable
Catalysts for Chemoselective Decarbonylation of Aldehydes
Wen-Hao Li,‡a Cun-Yao Li,‡b Li Yan,b Hai-Tao Tang,*a Heng-Shan Wanga, and Ying-Ming Pan*a, Yun-
Jie Ding*b
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
www.rsc.org/
A novel palladium nanoparticles (NPs)-metalated porous organic
ligand (Pd NPs/POL-xantphos) has been prepared for
chemoselective decarbonylation of aldehydes. The heterogenous
catalyst not only has excellent catalytic activity and
chemoselectivity, but also hold high activity after 10 runs of reuse.
The effective usage of this method is demonstrated through the
synthesis of biofuels such as furfuryl alcohol (FFA) via the highly
chemoselective decarbonylation of biomass-derived 5-hydroxy-
methylfurfural (HMF) with a TON up to 1540. More importantly, 9-
fluorenone could be obtained in one step through the
decarbonylation of 2-bromobenzaldehyde by using this
heterogeneous catalyst.
Scheme 1. Synthesis of POL-xantphos and corresponding Pd nanocatalyst.
It is imperative to search for new sources of both trans-
portation fuels and bulk chemicals due to the increasing
environmental concerns and urgent shortages of fossil
resources.1 Biomass-derived sugars are wonderful substitutes
for fossil resources due to their structural diversity and
abundance.2 Current strategies for the implementation of
biofuels from biomass-derived sugars are mostly directed to
the fermentation of cellulose into bioalcohols or the
conversion of biomass-derived sugars into synthesis gas with
the subsequent formation of synthetic fuels by a Fischer–
Tropsch process.3 As we all know, biomass-derived sugars are
significantly more oxygen rich than those frequently-used
chemicals and fuels. Thus, the chemoselective deoxygenation
of saccharides is central for the valid utilization of biomass-
derived carbohydrate feedstocks. At present, this goal is
mainly achieved by dehydration and decarbonylation/dec-
arboxylation.4
Furan derivatives are accessible from furfurals which have
already been produced on an industrial scale from biomass-
derived pentose.5 For example, 5-hydroxymethylfurfural (HMF)
which was obtained through selective dehydration from
hexoses or even cellulose6 can further transform into value-
added furan derivatives such as furfuryl alcohol (FFA) through
the decarbonylation by removing a CO moiety. Decarbonyl-
ation of HMF was first reported by Lillwitz, which suffered
from low chemoselectivity or needed a stoichiometric amount
of metal catalysts.7 To overcome the shortcomings, a series of
methods have been developed for effective decarbonylation of
HMF.8 However, high metal loading,8b high pressure in
supercritical CO2,8a low chemoselectivity,8c,8f or molecular
sieves were needed.8b,8e According to previous studies,
compared with homogeneous catalysts, their heterogeneous
counterparts with immobilized metals on high surface solids
could be more effective and chemoselective.9 Thus we intend
to use heterogeneous catalysts to improve the reactivity and
chemoselectivity of the decarbonylation of HMF.
aState Key Laboratory for the Chemistry and Molecular Engineering of Medicinal
Resources, School of Chemistry and Pharmaceutical Sciences of Guangxi Normal
University, Guilin 541004, People’s Republic of China.
E-mail: panym@mailbox.gxnu.edu.cn; httang@gxnu.edu.cn
bDalian National Laboratory for Clean Energy, Collaborative Innovation Center of
Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese
Academy of Sciences, Dalian 116023, China.
Porous organic ligands (POLs), a new kind of porous organic
polymer (POP) material, which can be synthesized through
free-radical polymerization routes from the corresponding
vinylfunctionalized diphosphine monomers by using AIBN
initiator under solvothermal conditions.10-12 Compared with
other supports, POLs have attracted attention from many
chemists due to their high surface area, large pore volume,
E-mail: dyj@dicp.ac.cn
†Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
‡These authors contributed equally to this work.
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
ChemComm
Page 2 of 4
View Article Online
DOI: 10.1039/C8CC03109F
COMMUNICATION
Journal Name
hierarchical porosity, superior stability, high efficiency, and the same curve as fresh Pd/POL-xantphos, which can be
excellent selectivity. More importantly, they have been used ascribed the stability of Pd NPs in the polymer supported
not only as a solid support but also a ligand for various metal catalysts (Figure S9). These structural characteristics are very
catalysts.11 The POLs also can swell in different solvents, and desirable for substrate-catalyst interactions. And the ICP-AES
the structure of those swollen polymers could be described as shows that palladium loading is 4.81 wt%.
solution. The “quasi-homogeneous” character of Metal/POLs
Table 1. Optimization of the reaction conditions.a
makes them have better catalytic activity than the “real
homogeneous” catalysts.12b For example,
a series of
phosphorus-doped porous organic polymers were used as
recyclable catalysts in hydroformyl-ation, isonitrile insertion,
and hydrogenation reactions by our group and others.12Herein,
we report a new Pd NPs-metalated porous organic ligand (Pd
NPs/POL-xantphos)13 as recyclable catalysts for the
chemoselective decarbonylation of aldehydes.
Entry
Catalyst
Ligand
1b
18
34
26
33
30
39
62
93
1c
23
31
33
26
25
27
18
2
1d
<1
6
1e
<1
<1
5
1
2
3
4
5
6
7
8
Pd(PPh3)4
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd NPs/POL-PPh3
/
PPh3
dppm
dppe
dppb
xantphos
/
The new type of porous organic polymer (POL-xantphos)
was designed and synthesized by free-radical polymerization
reaction using the corresponding vinylfunctionalized
diphosphine monomer. After Pd(OAc)2 loading and H2
reduction, the POL-xantphos could be turned into palladium
nanocatalyst Pd NPs/POL-xantphos (Scheme 1). To study the
structure–reactivity relationship, the prepared POL-xantphos
and Pd NPs/POL-xantphos were fully characterized.
10
4
<1
7
9
12
<1
<1
14
<1
<1
[b]
Pd NPs/POL-xantphos[b]
Pd/C[b,c]
/
9
/
42
<1
<1
<1
aReaction conditions: HMF 1a (0.5 mmol), K2CO3 (0.5 mmol), homogeneous
catalyst (5 mol%), ligand (12 mol%), 1,4-dioxane (1.5 mL), 140 oC, 6 h, under air
atmosphere, GC yield. bHeterogeneous catalyst (2 mol%). cDifferent Pd/C were
tested (See Table S1 in supporting information).
Due to the significance of decarbonylation of 5-hydroxymet-
hylfurfural (HMF) in developing sustainable energy, this
reaction was chosen to investigate the reactivity of the Pd
NPs/POL-xantphos (Table 1). And the reaction conditions were
carefully screened and results were depicted in Table 1. When
the reaction was treated with 5 mol% Pd(PPh3)4 in 1,4-dioxane
at 140 oC, the target product furfuryl alcohol (FFA) was
obtained with a yield of 18% (Table 1, entry 1). Then, ligands
were chosen to improve the chemoselectivity of this reaction.
Pd(OAc)2/xantphos was identified as the optimal homogen-
eous catalytic system for the reaction, increasing the yield of
FFA to 39% with poor chemoselectivity (Table 1, entries 2-6).
In order to further increase the yield of FFA, drawing on the
experience from preceding studies on metalated porous
organic ligands,12 we synthesized two heterogeneous catalysts,
Figure 1. a) Pore size distribution curves, b) N2 adsorption-desorption
isotherms, c) TG curve of POL-xantphos, d) SEM image of POL-xantphos.
In the 31P NMR spectrum of fresh Pd NPs/POL-xantphos, the
peak at 28.42 ppm can be ascribed to the palladium
coordinate with P atom (Supporting Information, Figure S8),
and the coordination of Pd nanoparticle with POL-xantphos is
further confirmed by XPS (Figure S7). TG curve of POL-
xantphos shows that the polymer remains intact at
temperatures up to 450 °C (Figure 1c). The nitrogen
adsorption-desorption analysis (Figure 1b) demonstrates that
POL-xantphos and Pd NPs/POL-xantphos have hierarchical
porosity, high surface area and large pore volume, which is
further confirmed by TEM and SEM images (Figure S2-S6 and
Figure 1d). Base on nonlocal density functional theory (NLDFT),
the pore sizes of POL-xantphos and Pd NPs/POL-xantphos were
primarily distributed between 0.7nm and 3 nm (Figure 1a). The
X-ray diffraction (XRD) shows POL-xantphos and Pd/POL-
xantphos are amorphous, XRD of fresh Pd/POL-xantphos
shows a peak at about 40 theta, indicating the appearance of
Pd NPs. XRD of used Pd/POL-xantphos demonstrates almost
13
which were used for the decarbonylation of HFM. The yield
of FFA was amazingly improved to 93% with excellent
chemoselectivity when we used Pd NPs/POL-xantphos (2
mol%) as a catalyst (Table 1, entry 7-8). In the meantime, we
chose the commercial catalyst Pd/C as a comparison, but the
yield of FFA catalysed by Pd/C was only 40% after 6 hours of
reaction (Table 1, entry 9). With this, the optimal conditions to
the decarbonylation of HFM were Pd NPs/POL-xantphos (2
o
mol%) as a catalyst in 1,4-dioxane with K2CO3(1 eq.) at 140 C
under air atmosphere (Table 1, entry 8).
The reusability is another significant characteristic of the
heterogeneous catalyst. We repeated the decarbonylation of
HMF with Pd NPs/POL-xantphos (Figure 2a) up to 10 times.
After each run, the nanocatalyst was recovered by vacuum
evaporation and washed sequentially with ethyl acetate, water,
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
ChemComm
Page 3 of 4
View Article Online
DOI: 10.1039/C8CC03109F
Journal Name COMMUNICATION
Table 2. The decarbonylation of aldehydes.a
and acetone. We were surprised to find that the nanocatalyst
could be used for at least 10 runs without losing any catalytic
activity. TEM images show Pd NPs were formed with no nota-
ble aggregation after the 10th run (Figure 2b and Figure 2c).
b)
c)
Figure 2. a) Recycling studies of Pd NPs/POL-xantphos for the decarbonylation of
HMF, b) TEM image of fresh Pd NPs/POL-xantphos, c) TEM image of used Pd
NPs/POL-xantphos
.
In order to study the industrial application of this catalyst,
we reduced the amount of heterogeneous catalyst to 0.05
mol%. The decarbonylation of 3.78 g of HMF produced the
corresponding product FFA with a yield of 77% and the TON up
to 1540 (Scheme 2).
Scheme 2. Industrial studies of Pd NPs/POL-xantphos for the decarbony-
lation of HMF.
To expand the scope of application of this catalytic system,
we examined the decarbonylation of other aldehydes. The
aldehydes bearing various aromatic substituents reacted
successfully. The electron-donating and electron-accepting
groups (R1 = 4-NMe2, 4-t-Bu, 4-NO2, 4-CN, 4-OMe, 4-COMe, 4-
COOH, 4-Ph, 3-Ph, 2-Ph, 4-vinyl, 4-acetylene) on the benzene
ring of the benzaldehyde all reacted smoothly (Table 2, entries
1-12). Ketonic carbonyl and carboxyl groups did not undergo
decarbonylation under this condition, indicating the
nanocatalyst has high chemoselectivity (Table 2, entries 6-7).
Due to the steric effect, probably, the yield of 3j was much
lower (Table 2, entry 10). Two molecules of CO can also be
successfully removed from the [1,1'-biphenyl]-4,4'-dicarbal-
dehyde with two formyl groups to give the decarbonylated
product 3m (Table 2, entry 13). And fused-ring aryl aldehydes
such as naphthaldehydes (2n), 9-anthraldehyde (2o) and
pyrene-1-aldehyde (2p) have all reacted smoothly in removing
one molecule of CO to give the decarbonylated products with
good yields (Table 2, entries 14-16). Various five and six
membered nitrogen-containing heterocyclic compounds (2q-2t
afforded the products (3q-3t) with good to satisfactory yields
aReaction conditions: aldehydes 2 (0.5 mmol), cyclohexane (2 mL), K2CO3
(0.5 mmol), Pd NPs/POL-xantphos (25 mg, 2 mol% Pd), 150 oC, 8 h, GC yield.
b1,4-Dioxane (1.5 mL) as solvent, t-BuOK (0.5 mmol) as base. cSolvent free.
(Table 2, entries 17-20). Furan or benzothiophene derivatives
can also be decarbonylated smoothly by this method (Table 2,
entries 21-22). The long chain alkyl aldehydes (2w) did not get
a satisfactory yield, maybe because of the influence of β-H
eliminating (Table 2, entries 23). Interestingly, several liquid
starting materials can also react without the involvement of
solvents to give the decarbonyla-ted products (Table 2, entry
11 and entry 23).
)
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
ChemComm
Page 4 of 4
View Article Online
DOI: 10.1039/C8CC03109F
COMMUNICATION
Journal Name
F
F
Pd/POL-xantphos (2 mol%)
4
(a) C. Wang, L. Wang, J. Zhang, H. Wang, J. P. Lewis and F.-S.
Xiao, J. Am. Chem. Soc., 2016, 138, 7880-7883; (b) L. R.
Baker, G. Kennedy, M. V. Spronsen, A. Hervier, X. Cai, S.
Chen, L.-W. Wang and G. A. Somorjai, J. Am. Chem. Soc.,
2012, 134, 14208-14216; (c) E. L. Kunkes, D. A. Simonetti, R.
M. West, J. C. Serrano-Ruiz, C. A. Gärtner and J. A. Dumesic,
Science, 2008, 322, 417-421; (d) S. Wang, V. Vorotnikov and
K2CO3 (1 equiv)
1,4-dioxane, 140 oC, 8 h
(1)
CHO
4a
4b
, 72%
Br
CHO
CHO
Pd/POL-xantphos (2 mol%)
K2CO3 (1 equiv)
1,4-dioxane, 140 o
(2)
C
OHC
CHO
4c
4d
4e
4f
4f
4d
Time
4e
6 h
6%
73%
17%
1%<
19%
51%
1%<
D. G. Vlachos, ACS Catal., 2015, 5, 104-112; (e) M.-Y. Chen,
12 h
48 h
22%
68%
C.-B. Chen, B. Zada and Y. Fu, Green Chem., 2016, 18, 3858-
3866; (f) J. Luo, H. S. Yun, A. V. Mironenko, K. Goulas, J. D.
Lee, M. Monai, C. Wang, V. Vorotnikov, C. B. Murray, D. G.
Vlachos, P. Fornasiero and R. J. Gorte, ACS Catal., 2016, 6,
4095-4104; (g) Y. Yang, Z. Du, Y. Huang, F. Lu, F. Wang, J. Gao
and J. Xu, Green Chem., 2013, 15, 1932-1940.
1) Pd/POL-xantphos (2 mol%)
K2CO3 (1 equiv)
100 oC, 8 h
2) 140 oC, 4 h
O
CHO
Br
(3)
4h, 75%
4g
5
6
(a) P. Gallezot, Chem. Soc. Rev., 2012, 41, 1538-1558; (b) S.
H. Pang, C. A. Schoenbaum, D. K. Schwartz and J. W. Medlin,
ACS Catal., 2014, 4, 3123-3131.
(a) Y. Roman-Leshkov, J. N. Chheda and J. A. Dumesic,
Science, 2006, 312, 1933-1937; (b) H. B. Zhao, J. E. Holladay,
H. Brown and Z. C. Zhang, Science, 2007, 316, 1597-1600; (c)
T. Wang, M. W. Nolte and B. H. Shanks, Green Chem., 2014,
16, 548-572.
Scheme 3. The applications of Pd NPs/POL-xantphos in decarbonylation of 4-
halobenzaldehydes.
Moreover, some special substrates could be converted into
interesting products using this nanocatalyst. For example,
when we used 4-halobenzaldehydes as the raw materials, fluo-
robenzaldehyde 4a can be decarbonylated to fluorobenzene
4b (Scheme 3, eq 1). But when we used 4-bromobenzaldehyde
4c as the substrate, we found that [1,1'-biphenyl]-4,4'-
7
8
L.D. Lillwitz, US4089871 (A), 1973.
(a) F. M. A. Geilen, T. V. Stein, B. Engendahl, S. Winterle, M.
A. Liauw, J. Klankermayer and W. Leitner, Angew. Chem. Int.
Ed., 2011, 50, 6831-6834; (b) J. Dai, X. Fu, L. Zhu, J. Tang, X.
dicarbaldehyde 4f
, [1,1'-biphenyl]-4-carbaldehyde 4e, and
biphenyl 4d can be obtained. And the yields of the products
were dependent on the reaction time (Scheme 3, eq 2).
Another interesting finding is that the amount of produced 9-
fluorenone 4h was more than that of decarbonylated product
when we used 2-bromobenzaldehyde 4g as a substrate in
standard conditions in one step (Scheme 3, eq 3). And this is
the first time that 9-fluorenone 4h was synthesized through
the Pd-catalyzed dimerization of 2-bromobenzaldehyde.
In summary, we have developed a highly chemoselective
and efficient method for decarbonylation of aldehydes with a
novel recyclable and highly stable heterogeneous
nanocatalyst. To study their structure-reactivity relationships,
the prepared POL-xantphos and Pd NPs/POL-xantphos were
fully character-rized. TEM images show that the Pd NPs are
highly discretely distributed in this porous polymer, which
results in the high activity of this nanocatalyst. More
importantly, this nanocatalyst can be reused in the
decarbonylation of HMF, which makes upgrading of this
significant biomass into biofuels possible for industrial
application.
Guo and C. Hu, ChemCatChem, 2016, 8, 1379-1385; (c) J.
Mitra, X. Zhou and T. Rauchfuss, Green Chem., 2015, 17, 307-
313; (d) Q. Meng,; C. Qiu, G. Ding, J. Cui, Y. Zhu and Y. Li,
Catal. Sci. Technol., 2016,
Yang, M.-Y. Chen, J.-J. Dai, Q.-X. Guo and Y. Fu,
ChemSusChem, 2013, , 1348-1351; (f) M. Chatterjee, T.
6, 4377-4388; (e) Y.-B. Huang, Z.
6
Ishizaka, A. Chatterjeeb and H. Kawanami, Green Chem.,
2017, 19, 1315-1326.
9
(a) Y.-B. Zhou, Y.-Q. Wang, L.-C. Ning, Z.-C. Ding, W.-L. Wang,
C.-K. Ding, R.-H. Li, J.-J. Chen, X. Lu, Y.-J. Ding and Z.-P. Zhan,
J. Am. Chem. Soc., 2017, 139, 3966-3969; (b) S. Lin, C. S.
Diercks, Y.-B. Zhang, N. Kornienko, E. M. Nichols, Y. Zhao, A.
R. Paris, D. Kim, P. Yang, O. M. Yaghi and C. J. Chang, Science,
2015, 349, 1208-1213; (c) L. Chen, Y. Yang, Z. Guo and D.
Jiang, Adv. Mater., 2011, 23, 3149-3154; (d) B. Li, Z. Guan, W.
Wang, X. Yang, J. Hu, B. Tan and T. Li, Adv. Mater. 2012, 24
,
3390-3395; (e) T. T. Adint and C. R. Landis, J. Am. Chem. Soc.,
2014, 136, 7943-7953.
10 (a) P. Bhanja, S. Chatterjee and A. Bhaumik, ChemCatChem.,
2016, , 3089-3098; (b) P. Bhanja, R. Gomes and A. Bhaumik,
RSC Adv., 2015, , 74916-74923.
8
5
11 (a) Q. Sun, Z. Dai, X. Meng and F.-S. Xiao, Chem. Soc. Rev.,
2015, 44, 6018-6034; (b) Q. Sun, Z. Dai, X. Meng, L. Wang
and F.-S. Xiao, ACS Catal., 2015, 5, 4556-4567.
We thank the National Natural Science Foundation of China
(21362002), Guangxi Natural Science Foundation of China
(2016GXNSFEA380001 and 2016GXNSFGA380005) and State
Key Laboratory for Chemistry and Molecular Engineering of
Medicinal Resources (CMEMR2017-A02 and CMEMR2017-A07)
for financial supports.
12 (a) W. Tong, W.-H. Li, Y. He, Z.-Y. Mo, H.-T. Tang, H.-S. Wang
and Y.-M. Pan, Org. Lett., DOI: 10.1021/acs.orglett.8b00886;
(b) Q. Sun, Z. Dai, X. Liu, N. Sheng, F. Deng, X. Meng and F.-S.
Xiao, J. Am. Chem. Soc., 2015, 137, 5204-5209; (c) C. Li,; K.
Sun, W. Wang, L. Yan, Y. Sun, Y. Wang, K. Xiong, Z. Zhan, Z.
Jiang and Y. Ding, J. Catal., 2017, 353, 123-132; (d) C. Li, L.
Yan, L. Lu, K. Xiong, W. Wang, M. Jiang, J. Liu, X. Song, Z.
Zhan, Z. Jiang and Y. Ding, Green Chem., 2016, 18, 2995-
3005; (e) R. Cai, X. Ye, Q. Sun, Q. He, Y. He, S. Ma and X. Shi,
Notes and references
1
(a) R. A. Kerr and R. F. Servise, Science, 2005, 309, 78-102; (b)
A. Corma, S. Lborra and A. Velty, Chem. Rev., 2007, 107
ACS Catal., 2017,
Wang, M. Jiang and Y. Ding, ACS Catal., 2016,
7, 1087-1092; (f) W. Wang, C. Li, L. Yan, Y.
6, 6091-6100;
,
2411-2502; (c) G. W. Huber, J. N. Chheda, C. J. Barret and J.
A. Dumesic, Science, 2005, 308, 1446-1450.
(g) Y.-B. Zhou, C.-Y. Li, M. Lin, Y.-J. Ding and Z.-P. Zhan, Adv.
Synth. Catal., 2015, 357, 2503-2508; (h) Z.-C. Ding, C.-Y. Li, J.-
J. Chen, J.-H. Zeng, H.-T. Tang, Y.-J. Ding and Z.-P. Zhan, Adv.
Synth. Catal., 2017, 359, 2280-2287.
2
3
C. Li, X. Zhao, A. Wang, G. W. Huber and T. Zhang, Chem.
Rev., 2015, 115, 11559-11624.
(a) G. W. Huber, S. Iborra and A. Corma, Chem. Rev., 2016,
106, 4044-4098; (b) C. Li, X. Zhao, A. Wang, G. W. Huber and
T. Zhang, Chem. Rev. 2015, 115, 11559-11624.
13 General procedures for the synthesis of POL-xantphos and
Pd NPs/POL-xantphos are depicted in supporting information
(Experimental Section).
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins