Production of 5-(formyloxymethyl)furfural from biomass-derived sugars using mixed acid catalysts and upgrading into value-added chemicals

Article abstract of DOI:10.1016/j.carres.2020.108140

In this work, 5-(formyloxymethyl)furfural (FMF) has been produced from biomass-derived hexose sugars within a biphasic reaction mixture consisting of aqueous formic acid (85%), a strong Br?nsted acid catalyst, and 1,2-dichloroethane as an organic extractant. Using a combination of aqueous hydrobromic acid and formic acid, under optimized condition (80 °C, 8 h, 10 wt% substrate loading), 68% isolated yield of FMF was obtained from fructose. FMF has been demonstrated as a renewable chemical building block for the synthesis of renewable chemicals of commercial significance such as 5-methylfurfural, 2,5-diformylfuran, and 2,5-furandicarboxylic acid in good to excellent isolated yields.

Full text of DOI:10.1016/j.carres.2020.108140

Carbohydrate Research 497 (2020) 108140
Contents lists available at ScienceDirect
Carbohydrate Research
journal homepage: www.elsevier.com/locate/carres
Production of 5-(formyloxymethyl)furfural from biomass-derived sugars
using mixed acid catalysts and upgrading into value-added chemicals
Saikat Dutta
Department of Chemistry, National Institute of Technology Karnataka (NITK), Surathkal, Mangalore, 575025, Karnataka, India
A R T I C L E I N F O
A B S T R A C T
Keywords:
In this work, 5-(formyloxymethyl)furfural (FMF) has been produced from biomass-derived hexose sugars within
a biphasic reaction mixture consisting of aqueous formic acid (85%), a strong Brønsted acid catalyst, and 1,2-
dichloroethane as an organic extractant. Using a combination of aqueous hydrobromic acid and formic acid,
under optimized condition (80 ◦C, 8 h, 10 wt% substrate loading), 68% isolated yield of FMF was obtained from
fructose. FMF has been demonstrated as a renewable chemical building block for the synthesis of renewable
chemicals of commercial significance such as 5-methylfurfural, 2,5-diformylfuran, and 2,5-furandicarboxylic
acid in good to excellent isolated yields.
Catalysis
5-(formyloxymethyl)furfural
Biomass
Renewable synthesis
Formic acid
1. Introduction
5-(bromomethyl)furfural (BMF) (Scheme 1), both of which can be pro-
duced directly from carbohydrates in satisfactory yields [9]. The hy-
The transition from the petroeconomy to the bioeconomy is driven
by incentives in renewable research, strict environmental regulations,
drophobic nature of CMF and BMF allows their relatively
straightforward isolation from the aqueous media by solvent-solvent
extraction. CMF and BMF have the potential to replace 1 in various
derivative chemistry [10]. However, both CMF and BMF have halogen
atoms in them that pose challenges in recycling the mineral acids used.
The economic feasibility of many derivative chemistries of CMF and
BMF mandate the efficient recovery of HCl and HBr, respectively, during
the transformation [11]. Besides, the production of CMF and BMF re-
quires the use of concentrated HCl and HBr, which are challenging to
work with. Therefore, there is significant interest in developing new
hydrophobic, stabler analogs of 1 that are straightforward to isolate
from the aqueous reaction mixture, but not containing halogen atoms in
their moieties [12]. Esters of 1, such as 5-(acetoxymethyl)furfural (AMF)
and 5-(formyloxymethyl)furfural (FMF 2), have attracted significant
attention over the past decade as non-halogenated, hydrophobic analogs
of 1 by using inexpensive carboxylic acids [13]. Being hydrophobic but
not containing halogen atoms, 2 enjoys the best of both worlds. Formic
acid, used for the preparation of 2, is a biogenic carboxylic acid and
relatively innocuous for the environment. Although purified CMF or 1
can be conveniently converted into AMF or 2, there is no significant
advantage in doing so since the two-step process entails producing 1 in
the first step [14]. One-pot preparation of 2 from biomass-derived car-
bohydrates using formic acid (FA) as the catalyst and reagent has also
been reported [15]. However, the synthesis of 2 using FA alone requires
relatively demanding conditions such as high reaction temperature and
and public outlook about
a greener, sustainable future [1].
Biomass-derived carbohydrates have been envisaged as a source of
renewable carbon that could potentially be transformed into fuels and
value-added chemicals via the chemical-catalytic pathway to maximize
the economic, environmental, and social benefits [2,3]. In this regard,
the acid-catalyzed hydrolysis and dehydration of carbohydrates into
furanics and levulinates is known for more than a century [4]. The
reasonably fast and biomass agnostic process enables selective removal
of oxygen atoms from the sugar molecules in the form of water without
extensive defunctionalization or carbon-carbon bond scission reactions
[5]. Production of 5-(hydroxymethyl)furfural (HMF 1) by the
acid-catalyzed dehydration of hexoses is a well-documented process in
the literature [6]. As a biorenewable chemical intermediate, 1 has been
used for the synthesis of a wide spectrum of products, including fuels
and fuel additives, solvents, monomers, agrochemicals, surfactants,
plasticizers, and pharmaceuticals [7]. One of the major advantages of 1
is that its structure contains only C, H, and O atoms. Though excellent
yields of 1 have been realized from simple sugars like fructose, its pro-
duction from polymeric carbohydrates requires special reaction condi-
tions. Besides, the inherent hydrophilicity and instability of 1 in aqueous
acid continue to dismay its purification, scalability, and process eco-
nomics [8]. The isolation problem of 1 can be alleviated by transforming
it into hydrophobic analogs like 5-(chloromethyl)furfural (CMF) and
E-mail address: sdutta@nitk.edu.in.
https://doi.org/10.1016/j.carres.2020.108140
Received 8 July 2020; Received in revised form 12 August 2020; Accepted 25 August 2020
Available online 29 August 2020
0008-6215/© 2020 Elsevier Ltd. All rights reserved.

S. Dutta
Carbohydrate Research 497 (2020) 108140
long duration [16]. 2,5-Dimethylfuran, a novel fuel oxygenate and
chemical feedstock, has also been sourced from 2 [17]. FA is primarily
sourced from methanol; however, novel synthetic routes have also been
explored [18]. Biogenic FA can be produced by the selective oxidation of
glucose or during the acid-catalyzed dehydration of hexoses [19]. FA has
a multitude of applications in sustainable chemistry as a one-carbon
(C1) compound, and show unusual reactivities when compared to
other carboxylic acids in the homologous series [20]. We envisioned that
a combination of FA with a strong Brønsted, non-nucleophilic acid
would help in the dehydration of carbohydrates into 1 and its esterifi-
cation with FA. Acid catalysts with a nucleophilic anion such as HCl and
HBr would lead to CMF and BMF, respectively, that would react with
formic acid in situ forming 2. Since pure 1 or CMF reacts with formic
acid to form 2, we anticipated that it will form exclusively or as a major
product in the reaction mixture. With no halogen atom incorporated into
the product molecule, the recovery problem of HCl or HBr would be
alleviated and make the process economically more attractive. There-
fore, in the acid mixture, FA would act as a reagent rather than an acid
catalyst. We propose using an aqueous-organic biphasic reaction
mixture that would help 2 to sequester into the organic solvent as soon
as it forms and shielded from hydrolysis and other decomposition
pathways in aqueous acid. After the reaction, the organic solvent con-
taining 2 could simply be phase-separated, and the aqueous acid recy-
cled. FA can be isolated from the acid mixture by vacuum distillation. In
this work, selective derivatization of 2 into important renewable
chemicals has also been undertaken.
Table 1
Production of FMF 2 from fructose using a mixture of formic acid and a strong
Brønsted acid catalyst. Reaction conditions: fructose (2 g), FA (20 mL, 85%),
acid catalyst (160 mol%), DCE (40 mL).
S/N
Acid catalyst
Reaction conditions
Yield of FMF (%)[a]
1
FA
Reflux, 20 h
Reflux, 8 h
Reflux, 16 h
Reflux, 8 h
Reflux, 16 h
Reflux, 24 h
15
48
50
68
38
42
2[b]
3
FA + HCl
FA + CH3SO3H
FA + HBr
FA + H2SO4
FA + H3PO4
4[c]
5
6
a
Isolated yield.
b
c
CMF formed as co-product was transformed into FMF.
BMF formed as co-product (minor) was transformed into FMF. Around 10%
LA was isolated from the aqueous layer along with 0.1 g of insoluble humin.
explained by the superior nucleophilicity of the chloride ion. Interest-
ingly, when purified CMF was reacted with FA in the presence of an
equivalent amount of ammonium formate, 2 was obtained in 87% iso-
lated yield within 1 h at 60 ◦C. However, ammonium chloride is pro-
duced as a salt waste. Therefore, the DCE layer containing the mixture of
CMF and 2 was phase-separated from the reaction mixture and then
reacted with fresh FA at 80 ◦C till the conversion of CMF was complete.
Evaporation of DCE and chromatographic purification gave a 48% iso-
lated yield of 2. When CH3SO3H was used as the Brønsted acid in
combination with FA, 2 was isolated from the DCE layer in a 50% yield
after refluxing for 16 h (entry 3). The longer duration was required due
to the lower Brønsted acidity of CH3SO3H when compared to HCl.
Shorter reaction time led to lower yields due to incomplete conversion of
fructose. When sulphuric acid was used, under identical conditions, the
yield of 2 was only 38%. Although the acidity of CH3SO3H and H2SO4 is
similar, the lower yield of 2 can be attributed to indiscriminate dehy-
dration of sugars by the latter, which led to noticeably more insoluble
humin formation. When H3PO4 was used as the catalyst, the reaction
provided only a 42% yield of 2 even after 24 h of refluxing. When HBr
(aq, 48%) was used as the catalyst, a mixture of BMF and 2 was initially
obtained, which was then transformed entirely into 2 by reacting with
fresh FA. After purification, 2 was isolated in 68% yield. The higher
yield of 2 in the case of HBr can be attributed to the stronger Brønsted
acidity of HBr and the easier transformation of BMF into 2 during the
reaction. The conversion of BMF to 2 also relatively faster when
compared to CMF since the bromide group is considerably more labile
and forms 2 by nucleophilic substitution reaction. Alternatively, 2 is
formed by the esterification of 1, formed as an intermediate by the hy-
drolysis of BMF. When the reaction was refluxed for 4 h, 2 was isolated
in only 42% yield. The lower yield of 2 was due to the incomplete
conversion of fructose. When the reaction time was extended to 12 h, the
yield of 2 was 53%. This is due to the fact that 2 (also BMF) continue to
degrade slowly in aqueous acid. Thus, the reaction should be quenched
2. Results and discussion
Initially, the dehydration of fructose was attempted in FA alone using
1,2-dichloroethane (DCE) as the extracting solvent. DCE was chosen as
solvent since chlorinated solvents work best in preparing furanics like
CMF and BMF, has a decent boiling point, and chemically inert under the
reaction conditions applied. In a typical reaction, fructose (2 g) was
dissolved in 20 mL of FA (85%, aq.) and 20 mL of DCE was added. The
biphasic mixture was placed in a pre-heated oil-bath and refluxed for 20
h under constant magnetic stirring. After cooling down the reaction
mixture, the DCE layer was phase separated and distilled off to obtain 2
in only 15% yield (after chromatographic purification over silica gel).
Slower kinetics of the dehydration of fructose by a weak acid like FA
(pKa 3.74) was responsible for the low yield of 2 since prolonging the
reaction time for another 12 h afforded additional 10% yield of 2. The
combination of FA with various strong Brønsted acids was then exam-
ined as a catalyst mixture for the production of 2 from fructose (Table 1).
When a mixture of HCl (35%, aq.) and FA was used (entry 2), the
reaction kinetics accelerated significantly. However, even after using
only a small quantity of HCl (5% of the total volume of acid catalyst),
CMF formed in noticeable quantity along with 2. The observation can be
Scheme 1. Structure of HMF 1 and some of its hydrophobic congeners (top), and preparation of FMF 2 by acid-catalyzed dehydration of fructose in formic
acid (bottom).
2

S. Dutta
Carbohydrate Research 497 (2020) 108140
at optimum time (ca. 8 h) when the rate of decomposition of 2 becomes
faster than its generation. The mixture of HBr and FA was then used as
the catalyst mixture for the formation of 2 from other sugars and car-
bohydrates. Glucose afforded a 52% yield of 2 under identical condi-
tions. The result may be explained by the relatively straightforward and
more selective dehydration of fructose from its fructofuranose form.
Glucose dehydrates into 1 directly or via isomerization into fructose first
during the reaction. In both cases, more side products form, and the
selectivity to 1 decreases. The trend is in accordance with most literature
reports for the preparation of 1. Sucrose gave a 58% yield of 2,
marginally better than glucose, possibly due to the presence of fructose
(50 mol%) in the sucrose moiety. In the case of polymeric carbohydrates
(e.g., starch, cellulose), the reaction mixture was refluxed for 24 h, but 2
was obtained in lower yields. The results may be explained by the
feedstock’s insolubility in the reaction mixture and slower kinetics of the
depolymerization step, leading to more side reactions. Polymeric car-
bohydrates like starch (soluble) gave poor yield of 2 (ca. 10%) even after
refluxing for 24 h. The result can be explained by the incomplete con-
version of starch due to slow depolymerization under the reaction
conditions used. However, a long time did not improve the yield any
further.
Scheme 2. Selective preparation of various renewable chemicals from FMF 2.
In the present case, the dilution of the FA also plays an important
role. When the reaction was carried out using 85% formic acid, 2 formed
as the major product. The mixture was then converted entirely to 2 by
reacting with fresh formic acid. When the reaction was repeated with
98% formic acid keeping all other parameters unaltered, BMF was found
to form as the major product. This demonstrates that the transformation
of BMF to 2 by nucleophilic substitution reaction is not the only
mechanistic pathway. The hydrolysis of BMF to 1 followed by its
esterification with formic acid, is also a viable route. When diluted
formic acid (ca. 50%) was used, 2 formed almost exclusively. The ex-
clusivity of 2 in the reaction mixture makes the next step of reacting with
fresh formic acid redundant. However, the reaction takes a much longer
time to give a decent yield. For example, after 20 h of reaction with 50%
formic acid (along with 160 mol% HBr), fructose gave around 35% yield
of 2.
reaction, a mixture of 2 and powdered Bi(NO3)3⋅5H2O (0.8 eq.) was
placed in a pre-heated (50 ◦C) oil bath and magnetically-stirred
continuously during the course of the reaction. The reaction was moni-
tored by FTIR spectroscopy, and stirring was continued till the conversion
of 2 was complete. DFF 4 was separated from the reaction mixture by
solvent extraction and isolated in 65% yield. When the oxidation of 2
was attempted in nitric acid (aq. 69%), FDCA 6 was isolated in a 48%
yield. In a typical reaction, 2 was dissolved in excess aqueous nitric acid
(8 mL for 0.5 g of 2) and heated at 80 ◦C overnight under constant
magnetic stirring. The reaction mixture was cooled down, and 6 was
filtered off as a white crystalline solid. Rehydration followed by
ring-opening of 2 in hot (ca. 120 ◦C) water led to the formation LA 5. The
reaction was conducted in a glass pressure reactor, and 5 was recovered
from the aqueous mixture in 92% isolated yield using ethyl acetate as
the extracting solvent.
Hydrolysis of 2 in excess of boiling water afforded 1 in excellent
isolated yield (ca. 90%). However, the extraction of 1 from the aqueous
reaction mixture required excess of organic solvent [21]. Besides,
chromatographic purification of 1 from levulinic acid (LA 5), formed as
a minor side product, was necessary [22]. However, when 2 was reacted
with anhydrous methanol at a slightly elevated temperature (ca. 50 ◦C)
in the presence of a catalytic amount of anhydrous K2CO3, 1 formed as
the sole product in near-quantitative yield. Interestingly, the reaction
did not work without the base catalyst. 1 was successfully isolated in
94% yield and in good purity by simply evaporating excess methanol.
Methyl formate, the volatile by-product, escaped from the reaction
mixture as soon as it formed. Catalytic reduction of 2 to 5-methylfurfural
(MF 3) was attempted by catalytic transfer hydrogenation conditions
using a combination of FA and ammonium formate and 5%Pd/C as the
catalyst. The reaction was conducted under conventional heating and
magnetic stirring. The reaction was monitored by TLC for the disap-
pearance of 2. The reaction completed within 1 h at 70 ◦C and 3 was
extracted from the reaction mixture by chloroform in 89% isolated yield.
MF 3 has been recognized as a potential fuel oxygenate and renew-
able furanic intermediate for further value addition [23]. Selective
oxidation of 2 was also attempted. The formylmethyl arm of 2 was
selectively oxidized to form 2,5-diformylfuran (DFF 4), whereas com-
plete oxidation of 2 led to 2,5-furandicarboxylic acid (FDCA 6) (Scheme
2). Both 4 and 6 have received attention as biorenewable monomers for
various polymeric applications [24,25]. Selective oxidation of 2 into 4
was achieved by using bismuth nitrate as the oxidant. Bismuth nitrate
has already been used as an inexpensive, non-toxic oxidant for con-
verting 1 into 4 in the presence of a heterogeneous catalyst [26]. In this
work, the reaction was conducted at a slightly elevated temperature
under the solvent-free condition without using any catalyst. In a typical
2.1. Conclusion
In summary, FMF 2 has been produced in decent isolated yields from
biomass-derived hexoses within an aqueous-organic biphasic system
using a mixture of formic acid and a strong Bronsted acid catalyst. FMF 2
was catalytically reduced to MF 3, a promising biofuel candidate,
selectively. FMF 2 was also converted into DFF 4 and FDCA 6, promising
renewable monomers for biopolymers, by selective oxidation. Meth-
anolysis and hydrolysis of FMF 2 led to HMF 1 and LA 5, respectively, in
excellent isolated yields. Lower concentration (ca. 50%) of formic acid
along with HBr formed 2 almost exclusively; however, longer duration
was required due to slower kinetics.
3. Experimental procedures
3.1. Production of 5-(formyloxymethyl)furfural (FMF 2) from fructose
Fructose (2.002 g) was added in a mixture of formic acid (FA, 20 mL)
and hydrobromic acid (2 mL, 48% aq., 160 mol%) taken in a 100 mL
round-bottomed flask and stirred to dissolve. To the solution, 20 mL 1,2-
dichloroethane (DCE) was added, and the biphasic reaction mixture was
placed in a pre-heated oil-bath and connected with a reflux condenser.
The mixture was refluxed for 8 h under constant magnetic stirring. After
the reaction, the mixture was cooled down to RT and filtered through a
filter paper under vacuum. The mixture was then transferred in a
separating funnel, and the DCE layer (bottom) was separated. The
aqueous layer washed with fresh DCE (10 mL). The DCE layers were
3

S. Dutta
Carbohydrate Research 497 (2020) 108140
combined and washed with distilled water (10 mL). The DCE layer was
then transferred in a 100 mL round-bottomed flask and 20 mL FA was
added. The biphasic mixture was heated in an oil-bath (60 ◦C) till all 5-
(bromomethyl)furfural (BMF), formed as a co-product, got converted
into FMF 2. The DCE layer was then phase-separated in a separatory
funnel, washed with water, and dried over anhydrous Na2SO4. Evapo-
ration of DCE under reduced pressure provided 2 as a brown liquid. The
liquid was chromatographed (Silica gel 60–120 mesh, CHCl3) to obtain
purified 2 as a light yellow liquid (1.162 g, 68%). 1H NMR (CDCl3, 300
MHz) δ (ppm): 9.64 (1H, s), 8.15 (1H, s), 7.28 (1H, d, 3.0 Hz), 6.68 (1H,
d, 3.0 Hz), 5.25 (2H, s). 13C NMR (CDCl3, 75 MHz) (δ ppm): 177.8,
160.1, 154.6, 152.8, 122.0, 112.9, 56.9. FTIR (ATR, cmꢀ 1): 3003, 2931,
2841, 1724, 1670, 1521, 1148, 1020, 748.
The chloroform layers were combined, dried over anhydrous Na2SO4,
and evaporated under reduced pressure to yield 4 as a light-yellow solid
(0.272 g, 65%). The compound was found to be NMR (1H&13C) pure;
however, the trace colored impurity may be removed by passing through
a plug of silica using chloroform as eluent. Alternatively, the trituration
of the solid in hot petroleum ether (60–80) produced need-like colorless
crystals of DFF 4. 1H NMR (CDCl3, 300 MHz) δ (ppm): 9.89 (s, 2H), 7.37
(s, 2H); 13C NMR (CDCl3, 75 MHz) δ (ppm): 179.2, 154.2, 119.2; FTIR
(ATR, cmꢀ 1): 3132, 3101, 2852, 1674.
3.6. Preparation of 2,5-furandicarboxylic acid (FDCA 6) from FMF 2
FMF 2 (0.500 g, 3.24 mmol) was taken in a 100 mL round-bottomed
flask and dissolved in 8 mL aqueous HNO3 (69%). The flask was placed
in a pre-heated (60 ◦C) oil-bath and stirred magnetically for 2 h. Then,
the temperature was increased to 80 ◦C and stirred overnight. After the
reaction, the flask was cooled down to room temperature, and excess
aqueous HNO3 was distilled off under reduced pressure. The residue was
then suspended in ice-cold water (10 mL) and filtered under vacuum.
FDCA 6 was obtained as a white crystalline solid. The solid was dried in
a hot-air oven at 60 ◦C until a constant weight was obtained (0.242 g,
48%). 1H NMR (DMSO‑d6, 300 MHz) δ (ppm): 7.29 (2H, s); 13C NMR
(CDCl3, 75 MHz) δ (ppm): 159.3, 147.5, 118.9.
3.2. Isolation of levulinic acid (LA 5)
The aqueous layer was filtered through a filter paper, and the filtrate
was saturated by adding sodium chloride. The saturated solution was
cooled in ice-water and extracted with ethyl acetate (6 × 10 mL). The
ethyl acetate layers were combined, dried over anhydrous Na2SO4, and
evaporated in a rotary evaporator under reduced pressure to yield a
brown liquid. The liquid was chromatographed over silica gel (60–120
mesh) using diethyl ether as eluent. Evaporation of the solvent provided
levulinic acid as light yellow oil (0.132 g, 10%). 1H NMR (CDCl3, 300
MHz) δ (ppm): 2.77 (t, 2H, J = 6.6 Hz), 2.64 (t, 2H, J = 6.6 Hz), 2.22 (s,
3H); 13C NMR (CDCl3, 75 MHz) (δ ppm): 206.6, 177.8, 37.7, 29.8, 27.7;
FTIR (ATR, cmꢀ 1): 3300, 2928, 1704, 1211, 1161.
3.7. Preparation of levulinic acid (LA 5) from FMF 2
FMF 2 (0.496 g, 3.22 mmol) was taken in a 100 mL glass pressure
vessel fitted with a Teflon-top and suspended in 20 mL water. A mag-
netic stir rod was introduced, the reactor was sealed, placed in a pre-
heated (120 ◦C) oil-bath, and stirred magnetically for 4 h. After the re-
action, the pressure vessel was cooled down to RT and opened. The
solution was saturated with solid NaCl, transferred into a separating
funnel, and extracted with ethyl acetate (5 × 10 mL). The organic layers
were combined, dried over anhydrous Na2SO4, and evaporated in a ro-
tary evaporator under reduced pressure to obtain crude LA as a brown
oil. The oil was passed through a plug of silica gel (60–120 mesh) using
diethyl ether as the eluent. LA was obtained as a clear liquid (0.344 g,
92%) by evaporating diethyl ether under reduced pressure.
3.3. Quantification of insoluble humin
The aqueous layer was passed through a pre-weighed filter paper,
and the filter paper was washed with an excess of distilled water. The
filter paper was dried in a hot-air oven at 60 ◦C till a constant weight was
achieved.
3.4. Preparation of 5-methylfurfural (MF 3) from FMF 2
FMF 2 (0.498 g, 3.23 mmol) was taken in a 50 mL round-bottomed
flask and dissolved in 3 mL of formic acid (85%). To the solution,
ammonium formate (1.020 g, 16.18 mmol) and 5%Pd/C (0.050 g) were
added. The flask was fitted with a magnetic stirring rod and a reflux
condenser and placed in a pre-heated (80 ◦C) oil-bath. The suspension
was stirred magnetically and monitored by TLC at regular intervals for
the disappearance of 2. After reaction (~1 h), the flask was cooled down
to room temperature, and the content was transferred into a separating
funnel. The reaction mixture was extracted with chloroform (3 × 10
mL). The chloroform layer was washed with distilled water, dried over
anhydrous Na2SO4, and evaporated in a rotary evaporator under
reduced pressure to provide crude 3 as a light-brown liquid. The slight
colored impurity in 3 was removed by passing it through a plug of silica
gel using chloroform as the eluent. Evaporation of the solvent under
reduced pressure afforded MF 3 as a clear liquid (0.318 g, 89%). 1H NMR
(CDCl3, 300 MHz) δ (ppm): 9.34 (s, 1H), 7.04 (d, 1H), 6.10 (d, 1H), 2.26
(s, 3H); 13C NMR (CDCl3, 75 MHz) δ (ppm): 176.7, 159.7, 151.7, 124.0,
109.4, 13.8; FTIR (ATR, cmꢀ 1): 2923, 1673, 1218, 1020.
3.8. Preparation of 5-(hydroxymethyl)furfural (HMF 1) from FMF 2
3.8.1. Strategy A
FMF 2 (0.502 g, 3.26 mmol) was taken in a 50 mL round-bottomed
flask and dissolved in 10 mL of dry methanol. To the solution, 0.020 g
of anhydrous K2CO3 was added, and the suspension was stirred
magnetically at 50 ◦C. The reaction was monitored by TLC for the
disappearance of 2. After the reaction, the reaction mixture was cooled
down to RT and filtered. Methanol was distilled off using a rotary
evaporator under reduced pressure to obtain crude 1. The crude 1 was
diluted in chloroform and passed through a plug of silica using 10% (v/
v) ethyl acetate in chloroform as the eluent. The evaporation of the
solvent under reduced pressure afforded 1 as a light-brown oil (0.386 g,
94%). 1H NMR (CDCl3, 400 MHz) δ (ppm): 9.59 (s, 1H), 7.24 (d, 1H,
3.20 Hz), 6.54 (d, 1H, 3.20 Hz), 4.73 (s, 2H); FTIR (ATR, cmꢀ 1): 2924,
2853, 1671, 1508, 1090.
3.5. Preparation of 2,5-diformylfuran (DFF 4) from FMF 2
3.8.2. Strategy B
FMF 2 (0.520 g, 3.37 mmol) was taken in a 100 mL round-bottomed
flask, and powdered Bi(NO3)3⋅5H2O (1.06 g, 2.68 mmol, 0.8 eq.) was
added. A magnetic stirring bar was added, and the flask was placed in a
pre-heated oil bath. The mixture was stirred magnetically and moni-
tored by TLC for the disappearance of 2. After a latent period of around
8–10 min, the evolution of brown NO2 gas started. The reaction took
nearly 45 min to complete. After the reaction, the flask was cooled down
to RT, and the yellow paste was extracted with chloroform (6 × 10 mL).
FMF 2 (0.500 g, 3.24 mmol) was added drop-wise in 50 mL of boiling
water taken in a 100 mL round-bottomed flask under vigorous magnetic
stirring. The reaction was monitored by TLC for the disappearance of 2.
After the reaction, the homogeneous solution was cooled down to RT.
The solution was transferred in a separating funnel and extracted with
ethyl acetate (5 × 10 mL). The ethyl acetate layers were combined, dried
over anhydrous Na2SO4, and evaporated under reduced pressure to yield
1 as a light yellow liquid (0.370 g, 90%).
4

S. Dutta
Carbohydrate Research 497 (2020) 108140
[13] (a) E.-S. Kang, Y.-W. Hong, D.W. Chae, B. Kim, B. Kim, Y.J. Kim, J.K. Cho, Y.
G. Kim, From lignocellulosic biomass to furans via 5-acetoxymethylfurfural as an
alternative to 5-hydroxymethylfurfural, ChemSusChem 8 (2015) 1179–1188,
https://doi.org/10.1002/cssc.201403252;
Declaration of competing interest
The authors declare that they have no known competing financial
interests or personal relationships that could have appeared to influence
the work reported in this paper.
(b) K. Kumar, A. Dahiya, T. Patra, S. Upadhyayula, Upgrading of HMF and
biomass-derived acids into HMF esters using bifunctional ionic liquid catalysts
under solvent free conditions, ChemistrySelect 3 (2018) 6242–6248, https://doi.
org/10.1002/slct.201800903.
Acknowledgments
[14] S. Shinde, K. Deval, R. Chikate, C. Rode, Cascade synthesis of 5-(acetoxymethyl)
furfural from carbohydrates over Sn-mont catalyst, ChemistrySelect 3 (2018)
8770–8778, https://doi.org/10.1002/slct.201802040.
This study was financially supported by the Science and Engineering
Research Board (SERB), India for funding support under the grant
number YSS/2015/001649. The author thanks Dr. Anukul Jana, TIFR,
Hyderabad, India, for helping in the NMR data collection.
[15] J. Zhang, N. Yan, Formic acid-mediated liquefaction of chitin, Green Chem. 18
(2016) 5050–5058, https://doi.org/10.1039/C6GC01053A.
[16] J. Yetao, C. Wei, Y. Sun, Z. Li, X. Tang, X. Zeng, L. Lin, S. Liu, One-pot conversion of
biomass-derived carbohydrates into 5-[(formyloxy)methyl]furfural: a novel
alternative platform chemical, Ind. Crop. Prod. 83 (2016) 408–413, https://doi.
org/10.1016/j.indcrop.2016.01.004.
[17] (a) Y. Sun, C. Xiong, Q. Liu, J. Zhang, X. Tang, X. Zeng, S. Liu, L. Lin, Catalytic
transfer hydrogenolysis/hydrogenation of biomass-derived 5-formyloxymethylfur-
fural to 2,5-dimethylfuran over Ni–Cu bimetallic catalyst with formic acid as a
hydrogen donor, Ind. Eng. Chem. Res. 58 (2019) 5414–5422, https://doi.org/
10.1021/acs.iecr.8b05960;
Appendix A. Supplementary data
Supplementary data to this article can be found online at https://doi.
org/10.1016/j.carres.2020.108140.
(b) S. De, S. Dutta, B. Saha, One-pot conversions of lignocellulosic and algal
biomass into liquid fuel, ChemSusChem 5 (2012) 1826–1833, https://doi.org/
10.1002/cssc.201200031;
References
(c) T. Thananatthanachon, T.B. Rauchfuss, Efficient production of the liquid fuel
2,5-dimethylfuran from fructose using formic acid as a reagent, Angew. Chem. Int.
Ed. 49 (2010) 6616–6618, https://doi.org/10.1002/ange.201002267;
(d) S.H. Shinde, C.V. Rode, Friedel–crafts alkylation over Zr-mont catalyst for the
production of diesel fuel precursors, ACS Omega 3 (2018) 5491–5501, https://doi.
org/10.1021/acsomega.8b00560;
[1] (a) I. Lewandowski, Bioeconomy: Shaping the Transition to a Sustainable,
Biobased Economy, Springer nature, 2018, https://doi.org/10.1007/978-3-319-
68152-8;
(b) E. de Jong, A. Higson, P. Walsh, M. Wellisch, Product developments in the bio-
based chemicals arena, Biofuels Bioprod. Bioref. 6 (2012) 606–624, https://doi.
org/10.1002/bbb.1360.
(e) X. Zhou, T.B. Rauchfuss, Production of hybrid diesel fuel precursors from
carbohydrates and petrochemicals using formic acid as a reactive solvent,
ChemSusChem 6 (2013) 383–388, https://doi.org/10.1002/cssc.201200718.
[18] J. Hietala, A. Vuori, P. Johnsson, I. Pollari, W. Reutemann, H. Kieczka, Formic acid,
ullmann’s encyclopedia of industrial chemistry, 2016, https://doi.org/10.1002/
14356007.a12_013.pub3.
[2] P. Sudarsanam, R. Zhong, S.V. den Bosch, S.M. Coman, V.I. Parvulescu, B.F. Sels,
Functionalised heterogeneous catalysts for sustainable biomass valorisation, Chem.
Soc. Rev. 47 (2018) 8349–8402, https://doi.org/10.1039/C8CS00410B.
[3] a) S. De, S. Dutta, B. Saha, Critical design of heterogeneous catalysts for biomass
valorization: current thrust and emerging prospects, Catal. Sci. Technol. 6 (2016)
7364–7385, https://doi.org/10.1039/C6CY01370H;
[19] (a) C. Wang, X. Chen, M. Qi, J. Wu, G. Gozaydin, N. Yan, H. Zhong, F. Jin, Room
temperature, near-quantitative conversion of glucose into formic acid, Green
Chem. 21 (2019) 6089–6096, https://doi.org/10.1039/C9GC02201E;
(b) T. Brouwer, M. Blahusiak, K. Babic, B. Schuur, Reactive extraction and
recovery of levulinic acid, formic acid and furfural from aqueous solutions
containing sulphuric acid, Separ. Purif. Technol. 185 (2017) 186–195, https://doi.
org/10.1016/j.seppur.2017.05.036.
(b) M. Hara, K. Nakajima, K. Kamata, Recent progress in the development of solid
catalysts for biomass conversion into high value-added chemicals, Sci. Technol.
Adv. Mater. 16 (2015), 034903, https://doi.org/10.1088/1468-6996/16/3/
034903.
[4] (a) A. von Grote, B. Tollens, Berichte 7 (1874) 1375;
(b) G. Düll, Action of oxalic acid on inulin, Chem. Ztg. 19 (1895) 216–220.
[5] a) L. Yang, G. Tsilomelekis, S. Caratzoulas, D.G. Vlachos, Mechanism of brønsted
acid-catalyzed glucose dehydration, ChemSusChem 8 (2015) 1334–1341, https://
doi.org/10.1002/cssc.201403264;
[20] K.F. Eidman, J.D. Belani, Formic acid, e-EROS encycl, Reagents Org. Synth. (2015)
1–7, https://doi.org/10.1002/047084289X.rf025.pub2.
[21] The Details of the Synthetic Procedure Is provided in the Supplementary
Information File with, Available with This Manuscript.
b) X. Zou, C. Zhu, Q. Wang, G. Yang, Catalytic dehydration of hexose sugars to 5-
hydroxymethylfural, Biofuels Bioprod. Biorefin. 13 (2018) 153–173, https://doi.
org/10.1002/bbb.1932.
[22] Levulinic acid is a well-recognized chemical platform in the biorefinery realm. For
reviews, see. a) F.D. Pileidis, M.M. Titirici, Levulinic acid biorefineries: new
challenges for efficient utilization of biomass, ChemSusChem 9 (2016) 562–582,
https://doi.org/10.1002/cssc.201501405;
[6] A SciFinder Search Found that 6743 Journals and 1877 Patents Were Published
during 2010 2020 Contained ‘5-hydroxymethylfurfural‘ in Their Title or Abstract
(Searched on June 24, 2020).
b) S. Kang, J. Fu, G. Zhang, From lignocellulosic biomass to levulinic acid: a
review on acid-catalyzed hydrolysis, Renew. Sustain. Energy Rev. 94 (2018)
340–362, https://doi.org/10.1016/j.rser.2018.06.016.
[7] R.-J. van Putten, J.C. van der Waal, E. de Jong, C.B. Rasrendra, H.J. Heeres, J.G. de
Vries, Hydroxymethylfurfural, A versatile platform chemical made from renewable
resources, Chem. Rev. 113 (2013) 1499–1597, https://doi.org/10.1021/
cr300182k.
[23] (a) G. Sun, J. An, H. Hu, C. Li, S. Zuo, H. Xia, Green catalytic synthesis of 5-
methylfurfural by selective hydrogenolysis of 5-hydroxymethylfurfural over size-
controlled Pd nanoparticle catalysts, Catal. Sci. Technol. 9 (2019) 1238–1244,
https://doi.org/10.1039/C9CY00039A;
[8] (a) F. Menegazzo, E. Ghedini, M. Signoretto, 5-Hydroxymethylfurfural (HMF)
production from real biomasses, Molecules 23 (2018) 2201, https://doi.org/
10.3390/molecules23092201;
(b) W. Yang, A. Sen, Direct catalytic synthesis of 5-methylfurfural from biomass-
derived carbohydrates, ChemSusChem 4 (2011) 349–352, https://doi.org/
10.1002/cssc.201000369.
(b) M. Dashtban, A. Gilbert, P. Fatehi, Recent advancements in the production of
hydroxymethylfurfural, RSC Adv. 4 (2014) 2037–2050, https://doi.org/10.1039/
C3RA45396K.
[24] (a) Z. Jia, J. Wang, L. Sun, J. Zhu, X. Liu, Fully bio-based polyesters derived from
2,5-furandicarboxylic acid (2,5-FDCA) and dodecanedioic acid (DDCA): from
semicrystalline thermoplastic to amorphous elastomer, J. Appl. Polym. 135 (2018)
46076, https://doi.org/10.1002/app.46076;
[9] (a) M. Mascal, E.B. Nikitin, Dramatic advancements in the saccharide to 5-
(chloromethyl)furfural conversion reaction, ChemSusChem 2 (2009) 859–861,
https://doi.org/10.1002/cssc.200900136;
(b) A.F. Sousa, C. Vilela, A.C. Fonseca, M. Matos, C.S.R. Freire, G.-J.M. Gruter, J.F.
J. Coelho, A.J.D. Silvestre, Biobased polyesters and other polymers from 2,5-fur-
andicarboxylic acid: a tribute to furan excellency, Polym. Chem. 6 (2015)
5961–5983, https://doi.org/10.1039/C5PY00686D;
(b) C.G. Yoo, S. Zhang, X. Pan, Effective conversion of biomass into
bromomethylfurfural, furfural, and depolymerized lignin in lithium bromide
molten salt hydrate of a biphasic system, RSC Adv. 7 (2017) 300–308, https://doi.
org/10.1039/C6RA25025D.
(c) G.Z. Papageorgiou, D.G. Papageorgiou, Z. Terzopoulou, D.N. Bikiaris,
Production of bio-based 2,5-furan dicarboxylate polyesters: recent progress and
critical aspects in their synthesis and thermal properties, Eur. Polym. J. 83 (2016)
202–229, https://doi.org/10.1016/j.eurpolymj.2016.08.004.
[10] (a) M. Mascal, 5-(Chloromethyl)furfural (CMF): a platform for transforming
cellulose into commercial products, ACS Sustain. Chem. Eng. 7 (2019) 5588–5601,
https://doi.org/10.1021/acssuschemeng.8b06553;
(b) N. Kumari, J.K. Olesen, C.M. Pedersen, M. Bols, Synthesis of 5-
bromomethylfurfural from cellulose as a potential intermediate for biofuel, Eur. J.
Org Chem. 2011 (2011) 1266–1270, https://doi.org/10.1002/ejoc.201001539.
[11] S. Dutta, M. Mascal, Novel pathways to 2,5-dimethylfuran via biomass-derived 5-
(chloromethyl)furfural, ChemSusChem 7 (2014) 3028–3030, https://doi.org/
10.1002/cssc.201402702.
[25] (a) T. Xiang, X. Liu, P. Yi, M. Guo, Y. Chen, C. Wendemiotis, J. Xu, Y. Pang, Schiff
base polymers derived from 2,5-diformylfuran, Polym. Int. 62 (2013) 1517–1523,
https://doi.org/10.1002/pi.4452;
(b) A.S. Amarasekara, D. Green, L.D. Williams, Renewable resources based
polymers: synthesis and characterization of 2,5-diformylfuran–urea resin, Eur.
Polym. J. 45 (2009) 595–598, https://doi.org/10.1016/j.eurpolymj.2008.11.012.
[26] D. Baruah, F.L. Hussain, M. Suri, U.P. Saikia, P. Sengupta, D.K. Dutta, D. Konwar,
Bi (NO3)3⋅5H2O and cellulose mediated Cu-NPs-A highly efficient and novel
catalytic system for aerobic oxidation of alcohols to carbonyls and synthesis of DFF
from HMF, Catal. Commun. 77 (2016) 9–12, https://doi.org/10.1016/j.
catcom.2016.01.003.
[12] (a) Z. Wang, Q. Chen, Conversion of 5-hydroxymethylfurfural into 5-ethoxyme-
thylfurfural and ethyl levulinate catalyzed by MOF-based heteropolyacid materials,
Green Chem. 18 (2016) 5884–5889, https://doi.org/10.1039/C6GC01206J;
(b) H. Xin, T. Zhang, W. Li, M. Su, S. Li, Q. Shao, L. Ma, Dehydration of glucose to
5-hydroxymethylfurfural and 5-ethoxymethylfurfural by combining Lewis and
Brønsted acid, RSC Adv. 7 (2017) 41546–41551, https://doi.org/10.1039/
c7ra07684c.
5