A ppm level Rh-based composite as an ecofriendly catalyst for transfer hydrogenation of nitriles: Triple guarantee of selectivity for primary amines

Article abstract of DOI:10.1039/c8gc03595d

Hydrogenation of nitriles to afford amines under mild conditions is a challenging task with an inexpensive heterogeneous catalyst, and it is even more difficult to obtain primary amines selectively because of the accompanying self-coupling side reactions. An efficient catalytic system was designed as Fe₃O₄@nSiO₂-NH₂-RhCu@mSiO₂ to prepare primary amines through the transfer hydrogenation of nitrile compounds with economical HCOOH as the hydrogen donor. The loading of rhodium in the catalyst could be at the ppm level, and the TOF reaches 6803 h^-1 for Rh. This catalytic system has a wide substrate range including some nitriles that could not proceed in the previous literature. The experimental results demonstrate that the excellent selectivity for primary amines is guaranteed by three tactics, which are the strong active site, the inhibition of side products by the hydrogen source and the special pore structure of the catalyst. In addition, the catalyst could be reused ten times without activity loss through convenient magnetic recovery.

Full text of DOI:10.1039/c8gc03595d

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DOI: 10.1039/C8GC03595D
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A ppm level Rh based composites as ecofriendly catalyst for
transfer hydrogenation of Nitriles: Triple guarantee of selectivity
for primary amine
Received 00th January 20xx,
Accepted 00th January 20xx
Lei Liua,b†, Jifan Lib,c†, Yongjian Aic, Yuhong Liua*, Jialiang Xiongc, Hongdong Wanga, Yijun Qiaoa,
Wenrui Liua, Shanchao Tana, Shaofei Fenga, Kunpeng Wanga, Hongbin Sunb* and Qionglin Liangc*
DOI: 10.1039/x0xx00000x
www.rsc.org/
Hydrogenation of nitrile to afford amine under mild conditions is a accompanying self-coupling reaction (Scheme 1).14-16 The
challenging work with inexpensive heterogeneous catalyst, and it is selective synthesis of primary amine through designing a
even more difficult to obtain primary amine selectively because of suitable catalytic system is a challenging task because of the
the accompanying self-coupling side reactions. An efficient catalytic high reactivity of intermediate imines.
NH2
N
system was designed as Fe3O4@nSiO2-NH2-RhCu@mSiO2 to
prepare primary amines through transfer hydrogenation of nitrile
compounds with economical HCOOH as the hydrogen donor. The
loading of rhodium in the catalyst could be at the ppm level, and
the TOF reaches 6803 h-1 for Rh. This catalytic system has a wide
substrate range including some nitriles that could not proceed in
previous literature. The experimental results demonstrate that the
excellent selectivity for primary amine is guaranteed by three
armors, which are the strong active site, the inhibition of side
products by the hydrogen source and the special pore structure of
the catalyst. In addition, the catalyst could be reused ten times
without activity loss through convenient magnetic recovery.
R
H•
H•
NH
R
R
expected
Cat

Cat

-NH3
R
H•
N
N
R
R
H
R
-NH3
H•
R
unexpected
unexpected
Scheme 1. The challenging selectivity of primary amine in nitrile
reduction.
Introduction
In comparison to traditional catalytic hydrogenation that
most researchers have focused on17-26, transfer hydrogenation
allows more benign conditions without the need of high
temperature and pressure equipment27, 28. Most of the current
studies are based on isopropanol and borane ammonia complex
as the hydrogen source. In 2014~2017, Sun’s group successively
reported the graphene supported bimetal NPs (NiPd, FePd,
CuNi) catalyzed the hydrogenation of R-NO2 or R-CN to R-NH2
with NH3BH3 as hydrogen donor.29-31 Contemporarily, Li’s group
developed respectively the monometallic Co and bimetal alloy
NPs (two of Co, Ni, and Cu), which were embedded in N-doped
Aromatic and aliphatic primary amines (denoted as R-NH2), as
significant pharmaceuticals and agrochemicals intermediates,
have attracted extensive interest from both academic and
industrial researchers, who are exploring more simple and
efficient strategies to establish carbon−nitrogen saturated
bonds.1-7 In this regard, hydrogenation of aromatic or aliphatic
nitrile (R-CN) compounds represented a convenient and
valuable process for the preparation of both aromatic and
aliphatic primary amines.8-13 Selectivity is a crucial problem in
the hydrogenation of nitriles because of the resulting mixtures
of primary, secondary and even tertiary amines via the
carbon, to selectively yield the imines or amines through the
33
transfer hydrogenation of nitriles in isopropanol.32,
Liu’s
group described the chemodivergent synthesis of primary and
secondary amines with nitriles and NH3BH3 as reactants and
catalyzed by homogeneous Co-pincer in 2016.34 In 2017, Fu’s
group fabricated a heterogeneous Ni2P to reduce nitrile
compounds to primary amines in the presence of NH3BH3 and
Rezaei’s group realized Chemo-selective reduction of nitrile
a. State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, People’s
Republic of China. E-mail: liuyuhong@tsinghua.edu.cn
b. Department of Chemistry, Northeastern University, Shenyang 110819, People’s
Republic of China. E-mail: sunhb@mail.neu.edu.cn
c. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry
of Education), Department of Chemistry, Tsinghua University, Beijing 100084,
People’s Republic of China. E-mail: liangql@mail.tsinghua.edu.cn
† This work was contributed equally by these authors.
Electronic Supplementary Information (ESI) available: [details of any supplementary
information available should be included here]. See DOI: 10.1039/x0xx00000x
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compounds using magnetic carbon nanotubes-supported Pt(II) turns out that the conversion of benzonitrile was unrealizable
View Article Online
catalyst and NaBH4.35, 36
in the presence of only low-loading Rh. Due to the good
DOI: 10.1039/C8GC03595D
Among all hydrogen carriers, formic acid is a readily performance of bimetallic integration, we tried to modulate the
available hydrogen donor. It is accessible via CO hydration, CO2 catalyst’s activity with a second transition metal such as Fe, Co,
reduction, and it is also a natural biomass-derivative, which Ni, Cu, which often appears in hydrogenation. Fortunately,
possesses the characters of high hydrogenation kinetics and when we turned to copper, the catalytic activity dramatically
hydrogen capacity.37 Consequently, transfer hydrogenation of increased, and the catalytic ability of the low-loading rhodium
nitrile by using HCOOH as a hydrogen donor represent a green, catalyst enabled the complete transformation of benzonitrile to
safe, and economical protocol. To the best of our knowledge, primary amines. To protect the catalytic active site, we designed
there are only two examples available for the reduction of a multiporous silica shell to encapsulate the metal sites, as we
nitriles using HCOOH up to the present. One is an inchoate work had observed that the reaction solution turned blue after a
on reducing the 2,4-dimethylbenzonitrile to the corresponding while and the selectivity of target product reduced due to the
benzyl amine using 10% Pd/C.38 The other is that Beller’s group dissolution of copper in the absence of outer mesoporous silica
transformed a series of nitrile compounds by employing shell (Table 1, entry 10).
commercially available Pd/C (10%) in 2014.39 But tremendous Table 1. Optimization of the catalyst and reaction conditions for
loading of palladium are needed in both of the previous works. transfer hydrogenation of nitrile to primary amine[a].
To develop an approach of low-loading noble metal and wide
N
range of substrate is endowed with significance and challenge.
Cat.
NH2
N
H
N
+
+
Bimetallic NPs, which integrate two distinct transition
metal atoms in different proportions, shine as the rising star in
the field of nanocatalysis recently.40 In comparison to their
single metal counterparts, they show reinforced properties
because of the altered electronic character through the strong
metal–metal interactions.41-44 The bimetallic alloy not only
precede in higher catalytic kinetics and selectivity than their
single analogues, but also enable to minimize the level of noble
metals in the components.45, 46
I
1a
III
II
Ratiob
10:1
10:1
10:1
10:1
10:1
20:1
Yield I (%)c
Entry
Hydrogen doner
HCOOH-NEt3
Conv. (%)c
Catalyst
FS-NH2-Rh@mSiO2
-
n.r.
23
1
2
3
20
HCOOH-NEt3
HCOOH-NEt3
HCOOH-NEt3
HCOOH-NEt3
FS-NH2-RhFe@mSiO2
FS-NH2-RhCo@mSiO2
13
14
15
14
98
4
5
FS-NH2-RhNi@mSiO2
FS-NH2-RhCu@mSiO2
FS-NH2-RhCu@mSiO2
>99
Based on our general interest in transfer hydrogenation,47-
98
HCOOH-NEt3
HCOOH-NEt3
HCOOH
>99
6
7
55
we herein developed a ppm level Rh-based catalytic
FS-NH2-RhCu@mSiO2
FS-NH2-RhCu@mSiO2
FS-NH2-RhCu@mSiO2
FS-NH2-RhCu
90
-
30:1
-
>99
n.r.
n.r.
reduction of nitriles to yield selectively primary amines with the
economical HCOOH as hydrogen donor. It can be concluded
from the above literature review that most of the active sites of
the catalyst are palladium. While rhodium and palladium
usually exist in the form of intergrown ore and their properties
are similar, few studies on applying Rh to catalyze the transfer
hydrogenation of nitriles have been conducted, so we focused
the active metal on rhodium. Considering the recyclability and
stability of the heterogeneous catalyst, we fabricated a
multilayered heterogeneous catalyst, Fe3O4@nSiO2-NH2-
RhCu@mSiO2. The inner core Fe3O4 sphere endows the catalyst
with magnetic recyclability; the active metals are embedded in
the inner layer silica shell by anchoring with -NH2 and
encapsulating with outer silica shell. The porous outer shell
make the reactants can reach the active sites. The preparation
flowchart of the catalyst are shown in scheme 2.56, 57
8
9
-
-
NEt3
HCOOH-NEt3
20:1
10
85
>99
aReaction conditions:benzonitrile (1 mmol), catalyst (10 wt%) FS represent for Fe3O4@nSiO2, hydrogen donor
(2 ml), 40 oC, 3 h. bRatio of HCOOH/NEt3 is based on molar ratio. cDetermined by GC using toluene as an
internal standard. n.r. = no reaction.
Subsequently, the influence of NEt3 concentration was
investigated (Table 1, entries 5-7). It is worth noting that no N-
formylbenzylamine was formed in any case. While neither
formic acid nor triethylamine alone allowed the reaction to
proceed, demonstrating a handful of base in HCOOH is
necessary (Table 1, entries 8-9).
The practical constitutes of the optimal catalyst are 0.05%
Rh and 7.29% Cu, which were determined by ICP-MS. That
signifies each batch reaction requires only 49 ppm Rh and the
TOF reached 6803 h-1 for Rh and 29 h-1 for Cu respectively. To
elucidate the real active catalyst species, a hot filtration test was
conducted. Once conversion rate reached 30% (20 min,
detected by GC), the optimal catalyst was separated with a
magnet and the reaction tube continued for 2 h under the
original condition. The additional conversion is not noticeable,
which manifested the amount leaching out was negligible.
Characterization
Scheme 2. The preparation flowchart of the core-shell-shell
structured catalyst.
Results and Discussion
Initially, we explored the reduction of benzonitrile 1a as a
benchmark system in the presence of low-loading Rh catalyst
with HCOOH/NEt3 (10:1) combination (Table 1, entries 1-5). It
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DOI: 10.1039/C8GC03595D
Figure 1. The HRTEM image (a,
characterization (d) of the catalyst.
b and c) and SAED
Initially, the morphology of the optimum catalyst was
characterized by high-resolution TEM. As shown in Figure 1a,
the material we fabricated presents uniform bubble-like
nanosphere and the average size is about 500 nm. Through
improving the resolution (Figure 1b, c and S1), we can
distinguish the inner core, the active metal site in the interlayer
and the pore structure of the catalyst. It’s worth mentioning
that only copper was detected by EDX, while rhodium element
content is below the detection threshold of this system
probably (Figure S2). Then we characterized this red circle area
in figure 1c by selected area electron diffraction (SAED). Figure
1d highlights a typical RhCu alloy phase with crystal lattice of
0.1815 nm, which is smaller than the Rh(200) spacing (0.1902
nm) but larger than the Cu(200) spacing (0.1808 nm). The
diffraction pattern of ferric oxide is indistinguishable probably
due to the so thick SiO2 coating.
The catalyst was further analyzed by X-ray photoelectron
spectroscopy (XPS) to obtain more in-depth information. The
survey XP spectrum (Figure. 2a) shows the existence of
elements C, O, Si, Cu and Rh. No detection of Fe element in
Fe3O4 may be attributed to the thick silica shell. The Rh 3d (300–
320 eV) and Cu 2p (925–975 eV) regions were also examined
(Fig. 2b and c). The Rh 3d spectrum shows the peak at 306.7 eV
that can be assigned to metallic Rh. And two main peaks are
observable in the Cu 2p region at 932.6 and 952.6 eV, indicating
that Cu atoms are in the metallic state. The negative shift for Rh
3d5/2 (~ 0.5 ev) and positive shift for Cu2p1/2 (~ 0.4 ev) compared
with their reference values indicate the altered electron
property, which is an additional evidence of alloying.
Figure 2. XPS spectra of the catalyst: (a) Survey; (b) Rh 3d; (c) Cu
2p.
The N2 sorption characterization was performed on the
catalyst, and the results are shown in Figure 3a. The material
displays typical type IV isotherm with an apparent hysteresis
loop in the low relative pressure region (0.05 < P/P0 < 0.4),
demonstrating the presence of about 2 nm pore. This is
confirmed by corresponding pore distribution curve (the inset,
BJH method). The high BET surface area of the material
(273.787 m2/g) indicates the abundant pore structure that is
beneficial to mass transfer process, which is in accord with
HRTEM images.
The magnetic recovery performance of the catalyst is
excellent (Figure 3b). The saturation magnetization value
reaches 30 emu g-1 in the field of 10000 oe. And the material is
superparamagnetic because of the absence of hysteresis
phenomenon, which is a good feature for heterogeneous
catalysts. The inset also shows that the evenly dispersed
nanoparticles were straightforward collected with a magnet. All
of above indicate the excellent magnetic recovery property of
the catalyst.
Figure 3. (a)N2 adsorption-desorption isotherm (the inset: pore
size distribution) (b) Magnetization curves (the inset: magnetic
separation in ethanol) of the catalyst.
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Table 2. Substrate scope of the transfer hydrogenation to afford which could be attributed to the ultra-strong activation to cyano
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primary amines[a].
group of active sites.
DOI: 10.1039/C8GC03595D
N
FS-NH2-RhCu@mSiO2
40 oC, 3 h
NH2
R
+
HCOOH/NEt3
R
Yield (%)b
98
Entry
1
Substrate
Conversion (%)b
Product
N
NH2
NH2
NH2
NH2
NH2
>99
N
N
>99
>99
2
3
95
93
93
N
N
4
5
>99
>99
92
97
N
N
N
NH2
NH2
NH2
>99
6
7
8
O
O
O
O
95
93
>99
>99
O
O
O
O
N
N
NH2
9
>99
>99
>99
96
Figure 4. Recyclability of the optimum catalyst.
Cl
Cl
The reusability is an essential advantage for heterogeneous
catalyst, thus recyclability should be verified. In this regard, we
conducted the reusability experiment for the FS-NH2-
RhCu@mSiO2 catalyst in model reaction. The regained catalyst
via magnetic separation were implemented in a new batch after
lavation with ethanol and drying. We can concluded from Figure
4 that the catalyst exhibited almost no activity change after ten
runs, even the reactions were carried out under relatively harsh
acidic conditions. We attributed the robustness to the
anchoring effect of NH2 and protective effect of outer
mesoporous silica shell to active sites.
NH2
NH2
NH2
NH2
10
97
96
Cl
Cl
N
N
N
N
N
F
F
F
F
F
F
F
F
11
98
94
12
13
>99
>99
F
F
H2
H2
N
N
H2
H2
N
N
NH2
NH2
14
15
93
98
>99
>99
HO
HO
NH2
16
17
N
>99
>99
96
98
CH3CH2NH2
CH3CN
aReaction conditions: nitriles (1 mmol), HCOOH-NEt3 (2 ml, 20:1) and catalyst (10 wt%) at 40 oC for 3 h.
bDetermined by GC using toluene as an internal standard.
Finally, the scope of substrate was investigated. As shown
in Table 2, 17 aliphatic or aromatic nitriles bearing electron-
withdrawing or electron-donating groups were smoothly
hydrogenated to the corresponding primary amines with
excellent selectivity under mild conditions using the ppm Rh-
based catalyst. The yield of products containing electron-
withdrawing group was slightly higher. Dehalogenation often
occurs in the hydrogenation catalyzed by a lavishly loaded noble
metal catalyst due to the activation of C-X bond.58, 59 However,
we did not detect the dehalogenated products using GC-MS,
which could be attributed to the ultralow rhodium loading
(Table 2, entries 9-12). Furthermore, aromatic nitriles bearing
amino, were smoothly transformed to target products (Table 2,
entries 13, 14), although it wasn’t transfer hydrogenated in
report because of the electronic/conjugation effect of -NH2 on
–CN31. Moreover, aliphatic nitriles are particularly noteworthy,
which is unrealizable using commercially available Pd/C
catalyst.39 In the present system, phenylacetonitrile underwent
the transfer hydrogenation successfully, affording the
corresponding primary amine in 96% yield (Table 2, entry 16),
Figure 5. Plausible Mechanism for the Catalytic Transfer
Hydrogenation of Nitriles to Primary amines by FS-NH2-
RhCu@mSiO2 with HCOOH.
Through the comprehensive analysis of experimental data,
we propose a plausible mechanism (Fig. 5). Initially, the ppm Rh
catalyzed the decomposition of HCOOH to produce active
hydrogen species and the imine intermediate and primary
amine appeared successively through hydrogenation. The
activation of nitrile group and C-N double bond was promoted
by RhCu alloy. The liberated primary amine is immediately
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5
6
7
8
9
R. Severin and S. Doye, Chem. Soc. Rev., 2007, 3V6i,ew14Ar0ti7cl-e Online
1420.
protonated by formic acid, thus reduces its nucleophilicity to
prevent the formation of secondary and tertiary amines. In
addition, the strong activation of the catalyst shortens the
lifetime of the imine intermediates, also avoids the self-coupling
reaction.47 Finally, the microtunnels of the catalyst restrict the
formation of bulky byproducts, such as gem-diamine, secondary
imine, secondary amine, and even tertiary amine. To verify this
point, we fabricated the analogous catalyst by etching the silica
shell with sodium hydroxide to create larger channels according
to the published procedure.60 And the larger pore diameter
(10.7 nm) renders the slightly reduced selectivity (~89%). The
N2-adsorption-desorption isotherm of the analogous catalyst is
shown in Figure S3. These three points constitute the “armor”
of the catalyst, which guarantees the excellent selectivity for
primary amine.
T. E. Mueller, K. C. Hultzsch, M. Yus, F.DFOoIu: 1b0e.1lo03a9n/Cd8MGC.0T3a5d9a5,D
Chem. Rev., 2008, 108, 3795-3892.
T. C. Nugent and M. El-Shazly, Adv. Synth. Catal., 2010, 352,
753-819.
S. Enthaler, K. Junge, D. Addis, G. Erre and M. Beller,
Chemsuschem, 2008, 1, 1006-1010.
S. Enthaler, D. Addis, K. Junge, G. Erre and M. Beller, Chem.
Eur. J., 2008, 14, 9491-9494.
10 X. Li, R. Van Zeeland, R. V. Maligal-Ganesh, Y. Pei, G. Power,
L. Stanley and W. Huang, ACS Catal., 2016, 6, 6324-6328.
11 K. M. Choi, K. Na, G. A. Somorjai and O. M. Yaghi, J. Am.
Chem. Soc., 2015, 137, 7810-7816.
12 X. Li, T. W. Goh, L. Li, C. Xiao, Z. Guo, X. C. Zeng and W.
Huang, ACS Catal., 2016, 6, 3461-3468.
13 X. Li, Z. Guo, C. Xiao, T. W. Goh, D. Tesfagaber and W. Huang,
ACS Catal., 2014, 4, 3490-3497.
14 D. Srimani, M. Feller, Y. Ben-David and D. Milstein, Chem.
Commun., 2012, 48, 11853-11855.
15 S. Chakraborty and H. Berke, ACS Catal., 2014, 4, 2191-2194.
16 S. Gomez, J. A. Peters and T. Maschmeyer, Adv. Synth. Catal.,
2002, 344, 1037-1057.
Conclusions
17 M. Yoshimura, A. Komatsu, M. Niimura, Y. Takagi, T.
Takahashi, S. Ueda, T. Ichikawa, Y. Kobayashi, H. Okami, T.
Hattori, Y. Sawama, Y. Monguchi and H. Sajiki, Adv. Synth.
Catal., 2018, 360, 1726-1732.
18 K. Tokmic, B. J. Jackson, A. Salazar, T. J. Woods and A. R.
Fout, J. Am. Chem. Soc., 2017, 139, 13554-13561.
19 A. Mukherjee, D. Srimani, Y. Ben-David and D. Milstein,
Chemcatchem, 2017, 9, 559-563.
20 C. Bornschein, S. Werkmeister, B. Wendt, H. Jiao, E. Alberico,
W. Baumann, H. Junge, K. Junge and M. Beller, Nature
Commun., 2014, 5, 4111.
21 R. Adam, E. Alberico, W. Baumann, H.-J. Drexler, R. Jackstell,
H. Junge and M. Beller, Chem. Eur. J., 2016, 22, 4991-5002.
22 Y. Cao, L. Niu, X. Wen, W. Feng, L. Huo and G. Bai, J. Catal.,
2016, 339, 9-13.
In summary, we have designed a ppm level Rh based
composites as an efficient and eco-friendly catalyst for the
transfer hydrogenation of nitriles to generate primary amine
with excellent selectivity. A variety of nitriles were transformed
to their corresponding primary amines with high yield using
economical HCOOH as the hydrogen donor. It is the strong
activation of active site to C-N multi bond, inhibition of side
products by hydrogen source and pore structure of the catalyst
that insure the shining performance. The high efficiency,
excellent selectivity, good compatibility and recyclability
highlight the merit of the catalyst, while the economically
available hydrogen source and mild reaction conditions also
render this system a promising methodology for generating
high-value primary amine.
23 S. Elangovan, C. Topf, S. Fischer, H. Jiao, A. Spannenberg, W.
Baumann, R. Ludwig, K. Junge and M. Beller, J. Am. Chem.
Soc., 2016, 138, 8809-8814.
24 R. Adam, C. B. Bheeter, J. R. Cabrero-Antonino, K. Junge, R.
Jackstell and M. Beller, Chemsuschem, 2017, 10, 842-846.
25 S. Chakraborty and D. Milstein, ACS Catal., 2017, 7, 3968-
3972.
Conflicts of interest
26 P. Ji, K. Manna, Z. Lin, X. Feng, A. Urban, Y. Song and W. Lin,
J. Am. Chem. Soc., 2017, 139, 7004-7011.
The authors declare no conflicts of interest.
27 S. Gladiali and E. Alberico, Chem. Soc. Rev., 2006, 35, 226-
236.
28 H.-U. Blaser, H. Steiner and M. Studer, Chemcatchem, 2009,
1, 210-221.
Acknowledgements
29 C. Yu, J. Fu, M. Muzzio, T. Shen, D. Su, J. Zhu and S. Sun,
Chem. Mater., 2017, 29, 1413-1418.
This work was financially supported by the Ministry of Science
and Technology (Nos.2017YFC0906902 and 2017ZX09301032),
National Natural Science Foundation of China (No. 51875303,
21621003 and 21872020) and Macau Science and Technology
Development Fund (129/2017/A3 and 089/2013/A3).
30 O. Metin, A. Mendoza-Garcia, D. Dalmizrak, M. S. Gultekin
and S. Sun, Catal. Sci, Technol., 2016, 6, 6137-6143.
31 H. Goksu, S. F. Ho, O. Metin, K. Korkmaz, A. M. Garcia, M. S.
Gultekin and S. Sun, ACS Catal., 2014, 4, 1777-1782.
32 J. Long, K. Shen, L. Chen and Y. Li, J. Mater. Chem. A, 2016, 4,
10254-10262.
33 J. Long, K. Shen and Y. Li, ACS Catal., 2017, 7, 275-284.
34 Z. Shao, S. Fu, M. Wei, S. Zhou and Q. Liu, Angew. Chem. Int.
Edit., 2016, 55, 14653-14657.
35 Y.-F. Zen, Z.-C. Fu, F. Liang, Y. Xu, D.-D. Yang, Z. Yang, X. Gan,
Z.-S. Lin, Y. Chen and W.-F. Fu, Asian. J. Org. Chem., 2017, 6,
1589-1593.
36 S. J. T. Rezaei, H. Khorramabadi, A. Hesami, A. Ramazani, R.
Amani and R. Ahmadi, Ind. Eng. Chem. Res., 2017, 56,
12256-12266.
Notes and references
1
2
T. E. Muller and M. Beller, Chem. Rev., 1998, 98, 675-703.
J. Seayad, A. Tillack, C. G. Hartung and M. Beller, Adv. Synth.
Catal., 2002, 344, 795-813.
3
4
F. Pohlki and S. Doye, Chem. Soc. Rev., 2003, 32, 104-114.
W. J. Tang and X. M. Zhang, Chem. Rev., 2003, 103, 3029-
3069.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
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Page 6 of 7
COMMUNICATION
Journal Name
37 H. H. Khoo, W. L. Ee and V. Isoni, Green Chem., 2016, 18,
1912-1922.
View Article Online
DOI: 10.1039/C8GC03595D
38 G. R. Brown and A. J. Foubister, Synthesis, 1982, 1036-1037.
39 M. Vilches-Herrera, S. Werkmeister, K. Junge, A. Boerner and
M. Beller, Catal. Sci, Technol., 2014, 4, 629-632.
40 D. Wang and Y. Li, Adv. Mater., 2011, 23, 1044-1060.
41 S. E. Habas, H. Lee, V. Radmilovic, G. A. Somorjai and P. Yang,
Nature Mater., 2007, 6, 692-697.
42 D. Xu, Z. Liu, H. Yang, Q. Liu, J. Zhang, J. Fang, S. Zou and K.
Sun, Angew. Chem. Int. Edit., 2009, 48, 4217-4221.
43 M. Sankar, N. Dimitratos, P. J. Miedziak, P. P. Wells, C. J. Kiely
and G. J. Hutchings, Chem. Soc. Rev., 2012, 41, 8099-8139.
44 R. Ferrando, J. Jellinek and R. L. Johnston, Chem. Rev., 2008,
108, 845-910.
45 I. N. Francesco, F. Fontaine-Vive and S. Antoniotti,
Chemcatchem, 2014, 6, 2784-2791.
46 S. Guo, S. Zhang and S. Sun, Angew. Chem. Int. Edit., 2013,
52, 8526-8544.
47 L. Liu, Y. Liu, Y. Ai, J. Li, J. Zhou, Z. Fan, H. Bao, R. Jiang, Z. Hu,
J. Wang, K. Jing, Y. Wang, Q. Liang and H. Sun, iScience, 2018,
8, 61-73.
48 Y. Ai, M. He, Q. Lv, L. Liu, H.-b. Sun, M. Ding and Q. Liang,
Chem. Asian. J., 2018, 13, 89-98.
49 H. B. Sun, Y. J. Ai, D. Li, Z. K. Tang, Z. X. Shao and Q. L. Liang,
Chem. Eng. J., 2017, 314, 328-335.
50 Y. J. Ai, Z. N. Hu, Z. X. Shao, L. Qi, L. Liu, J. J. Zhou, H. B. Sun
and Q. L. Liang, Nano Res., 2018, 11, 287-299.
51 J. J. Zhou, Y. N. Li, H. B. Sun, Z. K. Tang, L. Qi, L. Liu, Y. J. Ai, S.
Li, Z. X. Shao and Q. L. Liang, Green Chem., 2017, 19, 3400-
3407.
52 Y. L. Hongjie Bao, Lei Liu, Yongjian Ai, Junjie Zhou, Li Qi,
Ruihang Jiang, ZenanHu, Jingting Wang, Hongbin Sun,
Qionglin Liang, Chem. Eur. J., 2018, 24, 14418-14424.
53 Y. Ai, L. Liu, C. Zhang, L. Qi, M. He, Z. Liang, H.-b. Sun, G. Luo
and Q. Liang, ACS Appl. Mater. Interfaces, 2018, 10, 32180-
32191.
54 Y. Ai, M. He, F. Zhang, Y. Long, Y. Li, Q. Han, M. Ding, H.-b.
Sun and Q. Liang, J. Mater. Chem. A, 2018, 6, 16680-16689.
55 Z. Hu, J. Zhou, Y. Ai, L. Liu, L. Qi, R. Jiang, H. Bao, J. Wang, J.
Hu, H.-b. Sun and Q. Liang, J. Catal., 2018, 368, 20-30.
56 P. Li, C.-Y. Cao, H. Liu, Y. Yu and W.-G. Song, J. Mater. Chem.
A, 2013, 1, 12804-12810.
57 L. Liu, Y. Ai, D. Li, L. Qi, J. Zhou, Z. Tang, Z. Shao, Q. Liang and
H.-B. Sun, Chemcatchem, 2017, 9, 3131-3137.
58 W. Jiang, B. Xu, Z. Xiang, X. Liu and F. Liu, Appl. Catal., A,
2016, 520, 65-72.
59 A. M. Tafesh and J. Weiguny, Chem. Rev., 1996, 96, 2035-
2052.
60 J. Ge, Q. Zhang, T. Zhang and Y. Yin, Angew. Chem. Int. Edit.,
2008, 47, 8924-8928.
6 | J. Name., 2012, 00, 1-3
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Green Chemistry
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DOI: 10.1039/C8GC03595D
The 49 ppm Rh catalyst selectively transforms nitriles to primary amines with economical
HCOOH and exhibits a TOF value of 6803 h-1.