Conversion of furfural to tetrahydrofuran-derived secondary amines under mild conditions

Article abstract of DOI:10.1039/d0gc00119h

The production of amino-containing compounds from biomass is an important goal of research programs. Starting from carbohydrate-based furfural, a simple and highly efficient system was developed for producing a library of secondary and tertiary tetrahydrofurfurylamines under mild conditions (25 °C/1 bar H₂) with excellent yields (>90%). Commercially available Pd/Al₂O₃ proved to be a suitable catalyst and exhibited outstanding performance.

Full text of DOI:10.1039/d0gc00119h

View Article Online
View Journal
Green
Chemistry
Cutting-edge research for a greener sustainable future
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: S. Jiang, E. Muller,
F. Jerome, M. Pera-Titus and K. De Oliveira Vigier, Green Chem., 2020, DOI: 10.1039/D0GC00119H.
Volume 20
This is an Accepted Manuscript, which has been through the
Number
May 2018
Pages 1919-2160
9
7
Royal Society of Chemistry peer review process and has been
accepted for publication.
Green
Chemistry
Cutting-edge research for a greener sustainable future
rsc.li/greenchem
Accepted Manuscripts are published online shortly after 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
Information for Authors.
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 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 1463-9262
PAPER
Paul T. Anastas et al.
The Green ChemisTREE: 20 years after taking root with the 12
principles
rsc.li/greenchem

Please do not adjust margins
Page 1 of 6
Green Chemistry
View Article Online
DOI: 10.1039/D0GC00119H
COMMUNICATION
Conversion of furfural to tetrahydrofuran-derived secondary
amines under mild conditions
Shi Jiang,a,b Eric Muller,c François Jerôme,a Marc Pera-Titusb* and Karine De Oliveira Vigiera*
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
The production of amino-containing compounds from biomass is the manufacture of pharmaceuticals (e.g. furosemide), fibers,
an important goal of research programs. Starting from perfumes, polymers...9-10 The synthesis of furfurylamines has
carbohydrate-based furfural, a simple and highly efficient system been investigated from FF and 5-hydroxymethylfurfural by RA
was developed for producing a library of secondary and tertiary using homogeneous and heterogeneous catalysts.11-12 In the
tetrahydrofurfurylamines under mild conditions (25 °C/1 bar H2) literature, many works are dedicated to the synthesis of
with excellent yields (>90%). Commercially available Pd/Al2O3 furfurylamine THF-derived amines can be further generated by
proved to be a suitable catalyst and exhibited outstanding deep hydrogenation of the furan ring and was used as a
performance.
regulator in the synthesis of polybutadiene rubber with a
precise control of the microstructure,13 as well as for the
synthesis of poly(2-vinyl-4,4-dimethylazlactone) (pVDMA)-
derived (co)polymers with lower critical solution
temperature.14 Alternatively, THF amines can also be
synthesized through amination of furfuryl alcohol followed by
the saturation of the furan ring in the presence of Raney Ni at
Introduction
With the depletion of fossil fuel resources, transformation of
renewable and abundant biomass into valuable chemicals and
functional materials has become a growing field of interest.1
To date, the production of a broad range of chemicals from
lignocellulose containing C, H and O atoms, such as ethanol,
hexitols, furfural, 5-hexamethylfurfural, aldehydes/ketones
and acids, attracts continuous exploration.2 Nonetheless, the
synthesis of added-value N-compounds from biomass-derived
platform molecules sugars is still limited and has become an
important goal of research programs.3
Furfural (FF), issued directly from carbohydrates, is an
attractive and commercial platform molecule, which has been
identified as one of the top value-added chemicals with huge
market potential.4 FF can be used for producing a variety of
valuable derivatives, such as furfuryl alcohol,5 2-methylfuran,6
succinic acid,7 and maleic acid.8 FF also can be converted into
amino-compounds by reductive amination (RA). Furfurylamine
and tetrahydrofurfurylamine are important intermediates in
o
180 C, an amine and 0.1 MPa H2.15 Homogeneous catalysts
such as Ru-acridine complex and triruthenium dodecacarbonyl
complex have been also used for such reaction from furfuryl
alcohol.16 In our group, we synthesized the THF-amines with
high yields from furfural trough cascade reaction combining C-
C and C-N condensation reactions in the presence of Pd/Al2O3
and Amberlyst 26 catalysts.17 Based on these results, it was of
interesting to see if this catalyst can be applied to the direct RA
of furfural to THF-amines.
R
O
O
O
Pd/Al2O3
N
H
R: - alkyl chain
- aromatic group
EtOH, H2 ballon, rt
O
Pd/Al2O3
O
N
H
+
Amine
Neat, H2 ballon, rt
Pd/Al2O3
N
EtOH, ACN, H2
a. IC2MP UMR CNRS_Université de Poitiers 7285, ENSIP 1 rue Marcel Doré, TSA
41195, 86073 Poitiers Cedex 9, France, Email: karine.vigier@univ-poitiers.fr.
Scheme 1. Library of furan- and THF-derived secondary and tertiary amines that
can be achieved by RA of FF with amines over Pd/Al2O3.
b. Eco-Efficient Products and Processes Laboratory (E2P2L), UMI 3464 CNRS-Solvay,
3966 Jin Du Road, Xin Zhuang Ind. Zone, 201108 Shanghai, China, Email:
marc.pera-titus-ext@solvay.com
c. SOLVAY-Advanced Organic Chemistry & Molecule Design Laboratory, 85 Avenue
des Frères Perret, 69192 Saint Fons, France.
Here, we report that Pd/Al2O3 is an active, selective and
recyclable catalyst for the direct RA of FF to secondary THF-
amines at very mild conditions (Scheme 1) in the presence of
hydrogen and different amines. This strategy was further
extended to the one-pot synthesis of tertiary THF-amines using
acetonitrile (ACN).
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
Please do not adjust margins

Please do not adjust margins
Green Chemistry
Page 2 of 6
COMMUNICATION
Green Chemistry
as confirmed by mass/NMR analysis. The reactioVniewraAtreticloe fOntlhinee
conversion of 3a to 4a is slightly higherDtOhaI:n10t.1h0e39o/Dn0eGoCf0201a19tHo
4a (25.1 h-1 vs. 18.8 h-1). Based on previous work11,12 and on
control experiment, pure 2a could be fully converted to 4a and
3a could be also converted to 4a. The reaction pathway of 1a
to 4a is depicted scheme 2. Furfuryl or THF-alcohol was not
detected due to the very fast condensation between FF and
BuNH2.
Results and Discussion
The reaction between FF and 1-butylamine (BuNH2) was
chosen as a model example. In a first set of experiments, 1
mmol of FF (20 wt% in EtOH) were reacted in EtOH with 1
mmol of BuNH2 in the presence of 10 mg of supported Pt and
Pd catalysts (5 wt% metal loading) at room temperature for 12
h and 0.1 MPa H2 pressure (Table 1, entries 1-5). In all cases,
the FF conversion was above 99% with a carbon balance higher
than 90%. When 10 mg of Pt/C (5wt% Pt) was used as catalyst
(10 wt% with respect to FF), the furfurylimine (1a) and
furfurylamine (2a) were obtained as main products with 20%
and 70% yield, respectively, whereas the target THF-derived
amine (4a) was obtained with only 2% yield (entry 1). Pt/Al2O3
exhibited a similar performance with 78% and 10% yield of 1a
and 2a, respectively, and trace amounts of 4a (entry 2). A
drastically different behaviour was observed over 10 mg Pd
catalysts (0.45 mol% with respect to FF), favouring the
formation of 4a. Pd/Al2O3 exhibited the highest yield (97%) of
4a (entry 4). For comparison, Pd/C showed 24% yield of 4a
along with product 2a with 74% yield (entry 3). In all cases, the
THF-imine (3a) was not detected.
The Pd/Al2O3 catalyst loading was decreased from 10 to 5
mg (entry 5), a decline of the 4a yield from 97% to 77% was
observed along with an increase of the 2a yield from <1% to
20%. These results point out that 2a is a reaction intermediate
and that depending on the catalyst loading and thus the
reaction time, this product can be converted into 4a or not. A
high yield of 4a (>95%) could be attained at shorter times (90
min instead of 12 h) by increasing the temperature and H2
pressure to 80 oC and 1 MPa, respectively, with excellent
selectvity (entry 6), and the TOF could be increased from 17.9
to 143.3 h-1.
The effect of the solvent was further studied. EtOH
favoured the formation of 4a (entry 4), while THF promoted 2a
with 78% yield (entry 7). In the presence of toluene, 1a was
formed and only traces of 4a were detected (entry 8). Finally,
under neat conditions, 2a was the main product with 85% yield
(entry 9), which could be further increased under a slight
excess of BuNH2 (entry 10). This difference in the selectivity
can be ascribed to the solvent properties as it is reported in
the literature.18 Protic solvent (ethanol) is more active than
aprotic polar and aprotic apolar solvents in such reaction. They
promote the reaction between furfural and BuNH2, and they
could decreased solvent-catalyst interactions that will inhibit
the activity of the catalyst in the hydrogenation reaction.
The kinetic profile of the reaction over Pd/Al2O3 was
studied at room temperature and 0.1 MPa H2 pressure (Fig. 1).
Furfurylimine (1a) was spontaneously formed upon contacting
FF with BuNH2, After 30 min of reaction, about 18% of product
3a was generated along with product 1a, 2a and 4a with 30%,
50% and 2% yield, respectively. Indeed, after another 30 min,
product 2a reached a maximum yield of 72%, at the same time
we could get 11% yield of 3a and 12% yield of 4a.The yield of
4a increased gradually to 97% after 12 h on the benefit of 2a
a
Table 1. Catalyst screening for the RA of FF with BuNH2
O
N
H
2a
O
O
Cat.
N
O
H2N
+
1a
a
O
N
H
4a
Yield / %[e]
Entry
Catalyst
Solvent
TOFf(h-1)
1a
20
78
-
-
-
2a
70
10
74
<1
20
<1
78
57
85
98
4a
2
1
2
3
4
Pt/C
Pt/Al2O3
Pd/C
Pd/Al2O3
Pd/Al2O3
Pd/Al2O3
Pd/Al2O3
Pd/Al2O3
Pd/Al2O3
Pd/Al2O3
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
THF
Toluene
neat
neat
0.4
-
<1
24
97
77
98
10
<1
12
-
4.4
17.9
14.2
143.3
1.8
-
5[b]
6[c]
7
-
<1
27
-
8
9
2.2
-
10[d]
-
[a] Reaction conditions: FF (100 mg, 1.04 mmol), BuNH2 (77 mg), EtOH (5 g), 10 mg
of Pd/Al2O3 (0.45 mol% related to furfural), H2 (0.1 MPa), RT, 12 h; [b] 5mg for 5 wt%
Pd/Al2O3 ( 0.225 mol%); [c] H2 (1 MPa), 80 oC, 90 min; [d] BuNH2 (116 mg); [e] Yield
measured on the crude mixture. The FF conversion was >99% for all the catalytic
tests; [f]Turnover frequency (TOF) = (mol of 4a obtained)/(mol Pd x h).
(a)
Initial
O
N
Internal Standard
1a
O
30 min
3Na
O
1 h
2 h
N
H
2a
O
N
H
4a
6.0 6.2 6.4 6.6 6.8 7.0 7.2 7.4 7.6
Retention time (min.)
(b)100
80
1a
2a
3a
4a
60
40
20
0
0
2
4
6
8
10
12
Time (h)
2 | Green Chem., 2019, 00, 1-3
This journal is © The Royal Society of Chemistry 2019
Please do not adjust margins

Page 3 of 6
Green Chemistry
Please do not adjust margins
Green Chemistry
COMMUNICATION
Fig. 1 (a) Representative chromatogram of the products generated along the
reaction. (b) Kinetic profile of the RA of FF with BuNH2 over Pd/Al2O3. Reaction
conditions: FF (100 mg), BuNH2 (77 mg), EtOH (5 g), Pd/Al2O3 (10 mg), RT, H2 (0.1
MPa).
derived secondary amines over Pd/Al2O3 at very mild
conditions.
View Article Online
DOI: 10.1039/D0GC00119H
With these results in hand, we attempted the one-pot
synthesis of tertiary THF-derived amines over Pd/Al2O3 at mild
conditions. This reaction is challenging due to steric hindrance
disfavouring the formation of iminium/enamine intermediates.
A first experiment was carried out with FF and ethylbutylamine
at 50°C and 1 MPa H2 pressure. A low yield of the tertiary
amine (36%) was achieved after 12 h due to the formation of
furfuyl and THF-alcohols as by-products (Scheme 3).
O
N
H
2a
O
N
O
H
N
4a
1a
O
N
3a
Scheme 2. Reaction pathways for 1a hydrogenation over Pd/Al2O3.
To increase the yield of tertiary THF-amines, FF was
reacted with BuNH2 over Pd/Al2O3 in EtOH combined with N-
alkylation with ACN at a FF/BuNH2/ACN molar ratio of 1/1/3.
The kinetic profile showed that 2a was the primary product
generated, which reacted fast by deep hydrogenation of the
furan ring to 4a (Fig 3). After 100 min, 4a reached a maximum
yield of 93%, which decreased further due to N-alkylation with
ACN at the expense of the N,N-butylethyl-THF-amine (5a). A
possible reaction pathway is proposed in Scheme 4. The yield
of 5a reached a maximum yield of 84% after 12 h.
The recyclability of Pd/Al2O3 was further investigated (Fig.
2) using the reaction conditions that lead to the highest TOF
(143.3 h-1). After each run, the catalyst was separated from the
reaction medium by centrifugation and reused without any
further pre-treatment. The yield of 4a remained almost
constant during the first 5 runs, but displayed a slight decrease
after the 7th run at the expense of 2a while keeping total
selectivity to 4a and 2a around 95%. The spent catalyst after
the 8th run was washed with EtOH and dried in an oven at
80 °C overnight.
[a]
Table 2 Production of THF-derived amines from FF over Pd/Al2O3
100
(*)
R
O
O
Pd/Al2O3
EtOH, H2
N
O
H2N
1 mmol
R
+
H
1 mmol
80
60
40
20
0
R: - alkyl chain & aromatic group
O
O
O
O
N
H
N
N
H
N
H
10
6
H
b
c
d
e
: yield 93%
: yield 97%
: yield 95%
: yield 97%
OH
O
O
O
O
O
N
N
H
OH
N
N
OH
H
H
H
OH
h
: yield 93%
OH
f
g
: yield 97%
: yield 95%
i
: yield 91%
1
2
3
4
5
6
7
8
9
No. of Cycles
O
O
N
N
H
N
Fig. 2 Evolution of the yield of 4a in successive catalytic runs. Reaction conditions:
FF (2 mmol, 200 mg), BuNH2 (2 mmol, 153 mg), EtOH (10 g), Pd/Al2O3 (20 mg), H2
1 MPa), 80 oC, 90 min. The label (*) refers to a catalytic run after catalyst
calcination at 500 oC for 90 min.
H
H
j
k
l
: yield 95%
: yield 93%
: yield 47%
O
O
O
O
O
O
O
N
H
N
H
N
H
The spent catalyst was analyzed by thermogravimetric
analysis (Fig. S1). Two weight losses were observed at 40 °C
and 250 °C, which were similar to those observed on the fresh
catalyst. In contrast, the spent catalyst exhibited three
additional weight losses of ~1.6 wt% / 1.1 wt% / 3.4 wt% in the
range of 250-500 °C, which can be attributed to coke deposits.
By calcining the spent catalyst at 500 °C for 3 h, almost 95%
yield of 4a could be recovered after 90 min (9th run).
m
n
o
: yield 90%
: yield 94%
: yield 90%
N
O
O
N
H
N
N
H
N
H
N
q
p
: yield 93%
r
: yield 85%
: yield 90%
[a]
Reaction conditions: FF (1 mmol), Amine (1 mmol), EtOH (5 g), Pd/Al2O3 (10
mg), H2 (0.1 MPa), RT (b-i)/80°C (j-r), 12 h.
To assess the molecular diversity of THF-amines that could
be could obtained through this catalytic pathway, FF was
reacted over Pd/Al2O3 at room temperature and 0.1 MPa H2
pressure with different amines (Table 2). For alkyl- and
alcoholamines, the corresponding THF-derived amines (b-i)
were obtained with 91-97% yield. Besides, with the exception
of N-benzylamine (47% yield), aromatic amines afforded THF-
derived amines with 90-95% yield. Overall, these results clearly
show the efficient and selective one-pot synthesis of THF-
It is of interest to point out that the reaction temperature is a
key point which can make a balance between self N-alkylation
among acetonitrile and alkylation of THF-butylamine with
acetonitrile to obtain a high yield of tertiary amine and high
atom-economy (Fig. S2). No tertiary amine (5a) was observed
at room temperature, affording the formation of all the
products with a yield of 41%, 56% of products 2a, 4a,
respectively. A further increase of the reaction temperature to
This journal is © The Royal Society of Chemistry 2019
Green Chem., 2019, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Green Chemistry
Page 4 of 6
COMMUNICATION
Green Chemistry
80 °C resulted in a decrease of product 5a maximum yield from
84% to 69% along with 28% yield of 4a.
Furthermore, the catalytic performance of Pd/Al2O3 proved
itself again as a suitable and efficient catalyst for facile
synthesis of amines from bio-derived furfural.
View Article Online
O
N
6h (Yield 25 %)
DOI: 10.1039/D0GC00119H
O
12h (Yield 36 %)
Pd/Al2O3 (10 mg)
EtOH, H2(10 bar), 50 o
O
+
N
H
C
1 mmol
1 mmol
O
O
OH
N
OH
(1)
O
O
Pd/Al2O3
O
+
H2N
(2)
MeCN
Scheme 3 C-N bond formation by RA of FF with ethylbutylamine (1) and RA of FF
with BuNH2 associated with N-alkylation with ACN (2).
O
O
NH2
NH3
NH3
CH3CN
[H2]
[H2]
O
O
[H2]
N
H2N
N
N
H
[H2]
HN
O
O
[H2]
NH3
O
[H2]
N
N
N
N
H
H
NH2
Scheme 4 Proposed reaction pathway for the RA of FF with BuNH2 combined with N-alkylation.
100
80
60
40
20
0
O
Conflicts of interest
There are no conflicts to declare
N
H
4a
O
N
5a
O
Acknowledgements
N
H
2a
The authors would like to thank the French ANR agency for the
funding of FurCab Project ANR-15-CE07-0016. The authors are
also grateful to the Région Nouvelle Aquitaine for the funding
of this project through the FR CNRS INCREASE 3707, the chair
TECHNOGREEN and FEDER.
0
2
4
6
8
10
12
Time / h
Fig. 3 Kinetic profile of the RA of FF with BuNH2 and ACN to N,N-butylethyl-THF-
amine over Pd/Al2O3. Reaction conditions: FF (1 mmol), BuNH2 (1 mmol),
EtOH (5 g), Pd/Al2O3 (10 mg), H2 (1 MPa), 50 oC.
References
1
(a) A. A. Koutinas, C. Du, R. H. Wang and C. Webb, C.
Introduction to Chemicals from Biomass, Wiley, Hoboken,
2008, pp. 77; (b) J. J. Bozell and G. R. Petersen, Green Chem.,
2010, 12, 539; (c) M. Dusselier, M. Mascal, B. F. Sels, Top.
Curr. Chem., 2014, 353, 1. (d) G. W. Huber, S. Iborra and A.
Corma, Chem. Rev., 2006, 106, 4044; (d) Y. Liu, Y. Nie, X. Lu,
X. Zhang, H. He, F. Pan, L. Zhou, X. Liu, X. Ji and S. Zhang,
Green Chem., 2019, 21, 3499.
Conclusions
We presented in this study the one-pot synthesis of secondary
and tertiary THF-derived amines starting from furfural and
amines at very mild conditions. Commercially available
Pd/Al2O3 was found an efficient catalyst for producing a library
of amines with excellent yield by simply choosing the solvent.
In particular, ethanol favoured the synthesis of tetrahydro-
furfurylamine (98%). By reacting furfural, 1-butylamine and
acetonitrile in ethanol, a one-pot multi-reaction could occur
favouring the synthesis of N,N-butylethyl-THF-amines.
2
3
(a) N. Ji, T. Zhang, M. Zheng, A. Wang, H. Wang, X. Wang, J.
G. Chen, Angew. Chem. Int. Ed., 2008, 47, 8510; (b) J. Lange,
Angew. Chem. Int. Ed., 2015, 54, 13186; (c) A. Wang, T.
Zhang, Acc. Chem. Res., 2013, 46, 1377; (d) S. Jiang, C.
Verrier, M. Ahmar, J. Lai, C. Ma, E. Muller, Y. Queneau, M.
Pera-Titus, F. Jerome, K. De Oliveira Vigier, Green Chem.,
2018, 20, 5104.
(a) S. Imm, S. Bahn, M. Zhang, L. Neubert, H. Neumann, F.
Klasovsky, J. Pfeffer, T. Haas and M. Beller, Angew. Chem.
Int. Ed., 2011, 50, 7599; (b) J. Zhang, N. Yan, Green Chem.,
2016, 18, 5050; (c) V. Froidevaux, C. Negrell, S. Caillol, J-P.
Pascault and B. Boutevin, Chem. Rev., 2016, 116, 14181; (d)
M. Pelckmans, W. Vermandel, F. V. Waes, K. Mooen and B. F.
4 | Green Chem., 2019, 00, 1-3
This journal is © The Royal Society of Chemistry 2019
Please do not adjust margins

Page 5 of 6
Green Chemistry
Please do not adjust margins
Green Chemistry
COMMUNICATION
Sels, Angew. Chem. Int. Ed., 2017, 56, 14540; (e) M.
Pelckmans, T. Renders, S. van de Vyver and B. F. Sels, Green
Chem., 2017, 19, 5303; (f) N. Brun, P. Hesemann and D.
Esposito, Chem. Sci., 2017, 8, 4724.
(a) R. Mariscal, P. Maireles-Torres, M. Ojeda, I. Sádaba, M.
López Granados, Energy Environ. Sci., 2016, 9, 1144; (b) X. Li,
P. Jia, T. Wang, ACS Catal., 2016, 6 (11), 7621; (c) J.-P. Lange,
E. van der Heide, J. van Buijtenen, R. Price, ChemSusChem,
2012, 5 (1), 150.
View Article Online
DOI: 10.1039/D0GC00119H
4
5
6
7
8
9
Y. Ma, G. Xu, H. Wang, Y. Wang, Y. Zhang and Y. Fu, ACS
Catal., 2018, 8, 1268.
K. Yan, G. Wu, T. Lafleur and C. Jarvis, Renew. Sust. Energy
Rev., 2014, 38, 663.
H. Choudhary, S. Nishimura and K. Ebitani, Appl. Catal., A,
2013, 458, 55.
N. Araji, D. D. Madjinza, G. Chatel, A. Moores, F. Jerome and
K. De Oliveira Vigier, Green Chem., 2017, 19, 98.
(a) Q. Girka, N. Hausser, B. Estrine, N. Hoffmann, J. Le Bras, S.
Marinkovic and J. Muzart, Green Chem., 2017, 19, 4074; (b)
Z.Kuo, C. Bixian, Z. Xiaoting, K. Shimin, X. Yongjun, W. Jinjia,
ChemCatChem, 2019, 11, 5562; (c) M. Chatterjee, T. Ishizaka,
H. Kawanami, Green Chem., 2016, 18, 487;
10 (a) J. J. Martínez, E. Nope, H. Rojas, M. H. Brijaldo, F. Passos
and G. Romanelli, J. Mol. Catal. A: Chem., 2014, 392, 235; (b)
X. He, A. H. Conner, J. A. Koutsky, J. Polym. Sci., Part A:
Polym. Chem., 1992, 30, 533; (c) T. Ayusawa, S. Mori, T. Aoki
and R. Hamana, US4598159, 1986; (d) A. Dunbabin, F.
Subrizi, J. M. Ward, T. D. Sheppard and H. C. Hailes, Green
Chem., 2017, 19, 397.
11 (a) S. Nishimura, K. Mizuhori and K. Ebitani, Res. Chem.
Intermed., 2016, 42, 19; (b) M. Chatterjee, T. Ishizaka and H.
Kawanami, Green Chem., 2016, 18, 487; (c) T. Komanoya, T.
Kinemura, Y. Kita, K. Kamata and M. Hara, J. Am. Chem. Soc.,
2017, 139, 11493; (d) A. Dunbabin, F. Subrizi, J. M. Ward, T.
D. Sheppard and H. C. Hailes, Green Chem., 2017, 19, 397; (e)
K. Zhou, B. Chen, X. Zhou, S. Kang, Y. Xu, J. Wei,
ChemCatChem, 2019, 11, 5562; (f) A. Cukalovic, C. V. Stevens,
Green Chem., 2010, 12, 1201.
12 (a) J. A. T. Caetano, A. C. Fernandes, Green Chem., 2018, 20,
2494; (b) D. Chandra, Y. Inoue, M. Sasase, M. Kitano, A.
Bhaumik, K. Kamata, H. Hosono and M. Hara, Chem. Sci.,
2018, 9, 5949; (c) V. M. S. Isca and A. C. Fernandes, Green
Chem., 2018, 20, 3242; (d) D. Deng, Y. Kita, K. Kamata and M.
Hara, ACS Sust. Chem. Eng., 2019, 7, 4692; (e) A. García-Ortiz,
J. D. Vidal, M. J. Climent, P. Concepción, A. Corma and S.
Iborra, ACS Sust. Chem. Eng., 2019, 7, 6243.
13 (a) Y. Han, X, Chen, M. Lu, CN101845109A, 2010; (b) M, Lu,
Y. Ji, J. Dong. Y. Han, T. Yang, CN102358757A, 2012; (c) Z.
Xiao, J. Zeng, F. Lv, CN103508986B, 2015; (d) L. Lin, W. Chen,
Y, Sun, CN106349195A, 2017.
14 (a) Y. Zhu, J. Quek, A. B. Loew, P. J. Roth, Macromolecules,
2013, 46, 6475; (b) Y. Zhu, R. Batchelor, A. B. Lowe, P. J.
Roth, Macromolecules, 2016, 49, 672.
15 Y. Liu, K. Zhou, H. Shu, H. Liu, J. Lou, D. Guo, Z. Wei, X. Li,
Catal. Sci. Technol., 2017, 7, 4129.
16 (a) C. Gunanathan and D. Milstein, Angew. Chem., Int. Ed.,
2008, 47, 8661; (b) S. Imm, S. Bahn, L. Neubert, H. Neumann
and M. Beller, Angew. Chem., Int. Ed., 2010, 49, 8126.
17 S. Jiang, C. Ma, E. Muller, M. Pera-Titus, F. Jerôme, K. De
Oliveira Vigier, ACS Catal., 2019, 9, 8893.
18 S. Song, Y. Wang, N. Yan, Mol. Catal., 2018, 454, 87.
This journal is © The Royal Society of Chemistry 2019
Green Chem., 2019, 00, 1-3 | 5
Please do not adjust margins

Green Chemistry
Page 6 of 6
View Article Online
DOI: 10.1039/D0GC00119H
Graphical Abstract
Conversion of furfural to tetrahydrofuran-derived secondary amines under mild conditions
H2
R
O
R: - alkyl chain
- aromatic group
N
H
H2
O
O
Pd/Al2O3
H2
N
H
H2
N
H2
O
O
H
 One-pot
 Atom Economy
 Mild Conditions
Catalytic conversion of furfural to secondary tetrafurfurylamine under mild conditions of
temperature and hydrogen pressure