The Highly Effective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative Esterification Under Mild Conditions

Article abstract of DOI:10.1007/s10562-021-03754-x

The cobalt-based metal organic frameworks (Co-MOFs) catalyst has been prepared with using terephthalic acid and 4,4′-bipyridine as organic linkers by facile solvothermal method for one pot oxidative esterification. The prepared catalyst was pyrolysed at different temperature and then applied for oxidation of aldehyde using molecular oxygen as benign oxidant under mild conditions. The Co-MOFs pyrolysed at 800?°C (denoted as Co-MOFs-800) catalyst exhibited excellent catalytic activity, selectivity and recyclability toward the oxidative esterification of benzaldehydes. Furthermore, it can be reused up to 5 runs without significant loss of activity. Graphic Abstract: [Figure not available: see fulltext.]

Full text of DOI:10.1007/s10562-021-03754-x

Catalysis Letters
https://doi.org/10.1007/s10562-021-03754-x
The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst
for One Pot Oxidative Esterifcation Under Mild Conditions
Pagasukon Mekrattanachai1 · Lei Zhu2,3 · Naruemon Setthaya1 · Chakkresit Chindawong1 · Wei Guo Song2,3
Received: 12 January 2021 / Accepted: 22 July 2021
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021
Abstract
The cobalt-based metal organic frameworks (Co-MOFs) catalyst has been prepared with using terephthalic acid and 4,4′-bipy-
ridine as organic linkers by facile solvothermal method for one pot oxidative esterifcation. The prepared catalyst was
pyrolysed at diferent temperature and then applied for oxidation of aldehyde using molecular oxygen as benign oxidant
under mild conditions. The Co-MOFs pyrolysed at 800 °C (denoted as Co-MOFs-800) catalyst exhibited excellent catalytic
activity, selectivity and recyclability toward the oxidative esterifcation of benzaldehydes. Furthermore, it can be reused up
to 5 runs without signifcant loss of activity.
Graphic Abstract
Keywords Metal organic frameworks · Oxidative esterifcation · Cobalt nanoparticles · Oxidation
1 Introduction
The direct synthesis of esters from the oxidation of alde-
hydes is an important transformation in organic synthe-
sis due to these compounds fnd extensive applications
in the synthesis of various natural and bioactive products
[1–3]. The conventional method for the synthesis of esters
involves the reaction of carboxylic acids or acid deriva-
tives (acid chlorides and anhydrides) with alcohols, which
is a multistep process and often leads to the formation
of large amounts of waste and undesired by-products [4,
5]. In the recent years, direct catalytic transformation of
alcohol or aldehydes to esters, without using acid or acid-
derivative has gained considerable interest. Currently, a
number of various kinds heterogeneous catalysts for oxi-
dative esterifcation to the corresponding esters have been
reported in the literatures. However, most of the reported
* Pagasukon Mekrattanachai
pagasukon.me@up.ac.th
* Wei Guo Song
wsong@iccas.ac.cn
1
School of Science, Department of Chemistry, University
of Phayao, 19 Moo 2 Tambon Maeka Amphur,
Mueang Phayao 56000, Thailand
2
Beijing National Laboratory for Molecular
Sciences, Laboratory of Molecular Nanostructures
and Nanotechnology, CAS Research/Education Center
for Excellence in Molecular Sciences, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
3
University of Chinese Academy of Sciences, Beijing 100049,
China
Vol.:(0123456789)
1 3

P. Mekrattanachai et al.
catalysts are based on noble metals such as Au, Ag, Pd,
including bimetallic Au–Ag on supporting materials
[6–16]. These catalysts are not only expensive, but they
also involve the multistep synthetic procedures. There-
fore, the development of non-noble metal heterogeneous
catalyst with cost-efective and high efciency is a great
attractive for oxidative esterifcation.
2 Experimental Section
2.1 Preparation of Co‑Metal–Organic Frameworks
In this work Co-metal–organic frameworks catalyst was
prepared with a modifed method using the mixed sol-
vent between DI water and dimethylformamide or DMF
(1:1 v/v) as solvent [48–52]. In a typical synthesis,
Co(NO3)2·6H2O (3.75 mmol) was dissolved in the mixed
solvent of DI water and DMF (20 mL) to form a clear solu-
tion. Then terephthalic acid (3.75 mmol) in mixed solvent
(20 mL) was added by NaOH (7.5 mmol) in 5 mL DI water
yielding clear solution. Another linker, 4,4′-bipyridine
(3.75 mmol) in mixed solvent (20 mL) was also prepared.
After that, the terephthalic acid and 4,4′-bipyridine solu-
tions were added into Co(II) solution and the mixture was
stirred for 5 min. The mixture was transferred into Tefon-
lined autoclave and then heated at 120 °C for 12 h. The
powder was separated by centrifugation, washed by DMF,
DI water, and dried at 100 °C for overnight. Finally, the
powder was pyrolysed at high temperature (600, 700, 800
and 900 °C) for 3 h. under Ar gas (100 mL/min, 2 °C/min).
Transition metal nanoparticles (NPs) especially Co,
Cu, Ni, Fe etc. supported on N doped carbon material are
extraordinarily active non-precious metal catalysts for
green, economic and sustainable catalytic process [17–19].
In particular, Co NPs based carbon materials (Co@NC)
are found to be the powerful catalysts for oxidative esteri-
fcation because there are two potential catalytic active
sites consisting of Co NPs and Co–Nx sites in Co@NC
[20–24]. Generally, the common procedure for preparation
of Co NPs based carbon materials is wetness impregna-
tion of carbon materials (carbon black or carbon nanotube)
with Co(II)complex or Co(II) ion precursor, followed by
pyrolysis at 800 °C under inert gas [25–27]. Another facile
method is the carbonization of cobalt-nitrogen containing
metal organic frameworks (MOFs) such as ZIF-67 at tem-
peratures in the range of 600–900 °C to ensure the forma-
tion of Co–N doped graphitic material [28–30].
Metal–organic frameworks (MOFs), an important class
of crystalline porous materials, have received growing
interest for catalytic application [31–34]. MOFs are sol-
ids with permanent porosity which are built from nodes
(metal ions or clusters) coordinated with organic bridging
linkers to form well organized coordination networks. [35,
36]. The most signifcant feature of MOFs is their poten-
tial inner porosity and that guest molecules can access
the pores which are important for catalytic purposes. A
well known zeolite-type cobalt-organic frameworks (Co-
MOFs), ZIF-67 with 2-methylimidazole as organic linker
is widely investigated in several catalytic system such as
Fenton-like catalysis [37], pollutant photodegradation [38,
39], hydrogenation [40–42], epoxidation [43]. It is also
applied for oxidative esterifcation [44–47], and showed
the high activity. However, the investigation of Co-
MOFs with other organic linkers are still rare for organic
transformation.
2.2 Characterization
Powder X-ray difraction (XRD) patterns of the samples
were recorded with D8 Advance, Bruker using Cu-Kα
radiation with wavelength 1.5418 Å, 40 kV, 40 mA. The
cobalt contents in the samples were measured quanti-
tatively by inductively couple plasma atomic emission
spectroscopy (ICP-AES; IPPE-9000, Shimadzu Plasma
Atomic Emission Spectrometer). The surface morphology
of the materials was investigated using a scanning electron
microscope (FESEM, JEOL-6701F electron microscope).
The structure and the elemental distribution were deter-
mined using a high resolution transmission electron micro-
scope (TEM, JEOL 2100F electron microscope). The BET
surface area and pore size were measured using N2 adsorp-
tion/desorption isotherms at 77 K on a BET Micromerit-
ics ASAP 2460. X-ray photoelectron spectroscopy (XPS)
was performed by using an ESCALab220i-XL electron
spectrometer. The basicity of the prepared catalysts were
examined by CO2-TPD analysis. Temperature programmed
desorption (TPD) was carried out by using CO2 as the
probe molecule. Sample was pre-treated in He fow at
300 °C for 60 min and cooled to room temperature. After
being saturated with CO2, the sample was purged with
He for 40 min at room temperature to sweep the physical
molecule. Then sample was heated by 600 °C at the rate
of 10 °C/min. The signals were monitored by a thermal
conductivity detector (TCD). The elemental content (C, N
Herein, the cobalt-organic frameworks (Co-MOFs) with
using terephthalic acid and 4,4′-bipyridine as organic linkers
were prepared and studied in oxidative esterifcation under
O2 molecule as green oxidizing agent. Based on our knowl-
edge, this is the frst time to apply this catalyst for oxidative
esterifcation reaction. The developed Co-MOFs catalyst
has several advantages such as the use of a low cost metal,
high stability and excellent catalytic activity. Furthermore,
good magnetization of the synthesized catalyst allowed it
to be readily separated from the reaction mixture by using
external magnet.
1 3

The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative…
and O) of the prepared catalysts were also determined by
energy dispersive spectroscopy (EDS) technique in con-
junction with TEM.
vessel was evacuated and agitated under 1 MPa of O2, then
the mixture was heated to 60 °C for 3 h. Then, the catalyst
was separated by centrifugation, thoroughly washed with
methanol (3 × 10 mL) and dried at 90 °C overnight. After
that, it was reused for a consecutive reaction with fresh ben-
zaldehyde and methanol.
2.3 Oxidative Esterifcation of Benzaldehyde
and Benzaldehyde Derivative
The Co-metal–organic frameworks catalyst (20 mg), alco-
hol, benzaldehyde or benzaldehyde derivatives (1 mmol),
methanol (5 mL) and K2CO3 (0.5 mmol) were charged into
a reaction vessel equipped with a magnetic stirring bar. The
vessel was evacuated and agitated under 0.5 or 1 MPa of O2,
then the mixture was heated to 60 °C for the desired reac-
tion time. After the completion of reaction, the catalyst was
separated by centrifugation and the fltrate was determined
by GC-FID (Shimadzu GC‐2010‐Plus) and GC‐MS (Shi-
madzu GCMS‐QP2010) by using chlorobenzene as internal
standard.
3 Results and Discussion
3.1 Characterization of the Prepared Catalysts
The phase of prepared Co-MOFs sample has been confrmed
by powder X-ray difraction (XRD). Upon thermal treatment
at diferent temperatures, all XRD patterns showed three
peaks characteristic of metallic Co (JCDPF-15-0806) [38],
the intensity of which gradually increased along with ele-
vated annealing temperature, revealing the improved crystal-
linity of metallic Co and its signifcant efect with annealing
temperature (Fig. 1).
2.4 Reusability Test
The morphology of the prepared Co-MOFs catalysts
were studied by SEM and TEM techniques (Figs. 2 and 3).
The SEM and TEM images for the Co-MOFs pyrolysed at
600–800 °C obviously showed the regular distribution of
Co nanoparticles. The particles size of all samples were
also determined, and the larger particles size was observed
with the increased pyrolysis temperature from 600 to 900 °C
(Fig. 3). The distribution of Co nanoparticles is uniform with
The recyclability of the Co-metal–organic frameworks cata-
lyst was tested for oxidative esterifcation maintaining the
same reaction conditions as described above, except the
reaction was scaled up by factor 2. The Co-metal–organic
frameworks catalyst (40 mg), benzaldehyde (2 mmol),
methanol (10 mL) and K2CO3 (1 mmol) were charged into
a reaction vessel equipped with a magnetic stirring bar. The
Fig. 1 XRD patterns of Co-
MOFs catalysts which were
pyrolysed at 600, 700, 800 and
900 °C for 3 h. under Ar gas
1 3

P. Mekrattanachai et al.
Fig. 2 SEM images of Co-
MOFs catalysts pyrolysed at
600, 700, 800 and 900 °C for
3 h under Ar gas
the sizes of about 5.31, 7.50 and 7.61 nm, for the Co-MOFs
pyrolysed at 600, 700 and 800 °C respectively. While the
size of Co nanoparticles pyrolysed at 900 °C were increased
rapidly to about 47.96 nm and the distribution of Co nano-
particles was not uniform. This might be due to the aggre-
gation of Co nanoparticles at high pyrolysis temperature.
The Co size distribution results indicated that pyrolysis tem-
perature plays an important role in the dispersion of metal-
lic Co particles. And the higher pyrolysis temperature, the
higher Co loading was obtained because the more ligands of
MOFs could decompose at high temperature (Table S1, in
the Supporting Information). However, due to the high Co
metal content, partial particle agglomeration is occurred,
especially at high calcination temperature. The high-reso-
lution TEM (HRTEM) images of all samples (Fig. S1, in
the Supporting Information) unambiguously exhibited the
two lattice fringes with lattice spaces of 0.35–0.36 nm and
0.18–0.21 nm, corresponding to the graphitic layer domains
and the crystalline Co nanoparticle, respectively [39, 53].
This indicates the high crystallinity of the Co-MOFs sam-
ples. The element mapping of Co-MOFs-800 was also
shown in Fig. 4 and it demonstrated the co-existence and
homogenous dispersion of Co, C, O and N species.
pore sizes were in the range of 7.57–11.72 nm (Table S1 in
the Supporting Information).
To gain further insight into the catalyst structure, X-ray
photoelectron spectroscopy (XPS)characterization was per-
formed on the samples. In the cobalt region of Co-MOFs
samples, peaks characteristic of metallic Co were observed
with the typical binding energies of 794.03 and 778.05 eV,
assigned to Co 2p1/2 and Co 2p3/2 electrons of Co metal,
respectively (Fig. 6) [43, 54, 55]. Moreover, a dominant peak
of Co-MOFs samples annealed at 800 and 900 °C catalysts
were obviously seen at 779.06 eV, which should be ascribed
to N-coordinated metal (Co–Nx) [56, 57]. For Co-MOFs-600
and Co-MOFs-700 samples, the low intensity of this peak
was observed. The XPS spectra of C1s for all samples (Fig.
S3, in the Supporting Information) showed the binding
energy that can be assigned to C–C units at 284.5 0.3
eV, and C=O units at 288.5 0.4 eV [58]. In addition, the
N 1s spectrum for Co-MOFs-800 catalyst exhibited main
peak of pyridinic nitrogen with binding energy of 398.94
eV, confrming the coordination of nitrogen from 4,4′-bipy-
ridine linker [55] (Fig.S2 in the Supporting Information).
These results indicate that N atoms have been successfully
embedded in the carbon matrix, and some of them might
associate with the Co species to form Co–Nx sites, which
play an important role in oxidative esterifcation.
All N2 adsorption-desorption isotherms of all Co-MOFs
catalysts were close to type-IV with a hysteresis loop (Fig. 5)
[52]. The Co-MOFs calcined at 600 and 800 °C showed the
slightly higher BET surface area than the others and their
Base on the above results, metallic Co supported N-doped
carbon derived from Co-MOFs (Co@NC) was successfully
1 3

The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative…
Fig. 3 TEM images with their
sizes distribution of Co-MOFs
catalysts pyrolysed at 600, 700,
800 and 900 °C for 3 h under
Ar gas
prepared by carbonization of Co-MOFs at high temperatures
under inert gas.
350 and 400 °C were also observed for Co-MOFs-600
sample. On the other hand, Co-MOFs-900 catalyst exhib-
ited only peak of weak basic site, and the amounts of basic
sites for Co-MOFs-600, Co-MOFs-700, Co-MOFs-800
and Co-MOFs-900 were 1.30, 1.83, 1.87 and 1.13 mmol/g,
respectively. These results indicated that the decrease
of the amounts of strong basic sites contributed to the
declined of the catalysts [59–61].
Moreover, the relationship between basicity and cata-
lytic activity was investigated. CO2 -TPD was employed
to examine the basicity of Co-MOFs pyrolysed at
600–900 °C and the results were shown in Fig 7. For Co-
MOFs catalysts pyrolysed at 600, 700 and 800 °C, the
peaks of strong basic sites between 400 and 500 °C were
observed. And the small peak of weak basic site between
1 3

P. Mekrattanachai et al.
Fig. 4 HRTEM images of Co-
MOFs-800 catalyst and EDS
mapping
Fig. 5 a N2 adsorption–desorption isotherms and b pore size distribution of Co-MOFs catalysts pyrolysed at 600, 700, 800 and 900 °C for 3 h
under Ar gas
1 3

The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative…
Fig. 6 XPS analysis of Co-MOFs catalysts which were pyrolysed at 600, 700, 800 and 900 °C for 3 h under Ar gas
3.2 Catalytic Activity
The catalytic activity of the synthesized Co-MOFs catalysts
was tested for the oxidative esterifcation of benzaldehyde
and benzylic alcohol with methanol to give methyl benzoate.
Typically, the model reaction was performed at 60 °C using
oxygen molecule as an oxidant in the presence of K2CO3 as
base. After fnishing the reaction, the catalyst powder was
removed by centrifugation, and then the fltrate was deter-
mined by GC-FID and GC-MS by using chlorobenzene as
internal standard to confrm the obtained products. As a
result, the main peak of methyl benzoate was observed and
the another was (dimethoxymethyl)benzene or acetal byprod-
uct. The results of the optimization experiments were sum-
marized in Table 1. As can be seen, Co-MOFs calcined at
800 °C (denoted as Co-MOFs-800) showed the best activ-
ity and selectivity to the only targeted product within 12 h
(entry 3). For comparison, the prepared catalyst with diferent
pyrolysis temperatures showed lower activity or/and selectiv-
ity to varying extents (entries 1-4). This indicated that the
higher Co content in the high pyrolysed temperature catalyst,
Fig. 7 CO2-TPD profles of Co-MOFs-600, Co-MOFs-700,
CoMOFs-800 and Co-MOFs-900 catalysts
1 3

P. Mekrattanachai et al.
Table 1 Oxidative esterifcation of benzaldehyde and methanol over Co-MOFs catalysts which were pyrolysed at diferent temperatures
Entry
Catalyst
O2 Pressure (MPa)
Time (h)
Conv. (%)
Sel. (%)
Sel. (%)
CH3
O
O
CH3
OCH3
O
1
2
3
4
5
6
7
8
Co-MOFs-600
Co-MOFs-700
Co-MOFs-800
Co-MOFs-900
Co-MOFs-800
Co-MOFs-800
Co-MOFs-800
Co-MOFs-800a
Co-MOFs-800b
Co-MOFs-800b
No catalyst
1
1
1
1
1
1
0.5
0.5
1
12
12
12
12
9
66
74
100
96
100
94
96
81
75
85
10
51
79
96
92
83
72
94
99
1
49
21
4
8
17
28
6
6
12
12
12
24
24
1
9
10
11
99
99
97
1
1
1
3
Reaction conditions: Co-MOFs catalyst (20 mg), benzaldehyde (1 mmol), methanol (5 mL), K2CO3 (0.5 mmol), 60 °C reaction temperature
aAmount of Co-MOFs-800 was 10 mg
bWithout base
the higher catalytic activity was observed and the optimized
Co loading in this experiment was 32.3 wt%. Although the
Co content of the Co-MOFs catalysts pyrolysed at 900 °C is
the highest (36.2 wt%), its catalytic activity was lower than
that Co-MOFs catalyst pyrolysed at 800 °C. This might be
due to the lowest basic sites in Co-MOFs-900, the aggrega-
tion and the large size of Co nanoparticles (47.96 nm). The
Co-MOFs-800 catalyst was further tested at 0.5 MPa O2.
As a result, it also exhibited the excellent catalytic activity
with 96% conversion and 94% selectivity of methyl benzo-
ate (entry 7). The presence of base was demonstrated to be
necessary for the conversion (entries 9–10). After having
demonstrated the excellent activity of Co-MOFs-800 in the
model reaction, a wide range of aldehydes containing elec-
tron donating as well as withdrawing groups were oxidized
under described experimental conditions. The results were
summarized in Table 2. All the substrates were smoothly
oxidized to give the desired products with excellent catalytic
performances. In general, aromatic aldehydes substituted
with electron-withdrawing groups such as para-nitro, fuoro
and bromo were found to be more reactive and aforded
desired products with high selectivities of ester products than
those containing electron donating groups and lower elec-
tronegativity groups (para-methoxy and chloro groups) [62].
For ortho-nitrobenzaldehyde (entries 6–7), the reactivities
were lower than the others which owing to the steric efect
of substrate structure, resulting the difculty in the interac-
tion between substrate and catalyst surface [63]. According
to the XPS analysis shown above, the catalytic active centres
in this prepared catalyst could be metallic Co NPs and Co–Nx
sites in this prepared catalyst, resulting the excellent catalytic
activity of this catalyst for oxidative esterifcation of benza-
ldehyde. This correspond to the synergistic catalytic efect
between Co–Nx sites and Co NPs in the previous literature
[64].
The catalytic study was then extended to the oxidative ester-
ifcation of various benzylic alcohols using the Co-MOFs-800
catalyst, and the results were summarized in Table 3. As a
result, various benzylic alcohols were converted into the cor-
responding methyl esters in moderate to high conversions
(53–96%). The benzylic alcohols substituted with electron
donating groups (–OCH3 and –CH3) showed a higher conver-
sions (entry 2 and 3) in comparison to benzylic alcohols sub-
stituted with electron withdrawing groups (–Br, –NO2, –Cl).
The aldehyde by-product was also observed in oxidative esteri-
fcation of alcohol. Benzyl alcohol were oxidized to only ben-
zaldehyde, when benzylic alcohols substituted with methoxy
and methyl group were oxidized to desired esters with moder-
ate selectivities (entry 2 and 3). On the other hand, benzylic
alcohols substituted with –Br and –Cl group were oxidized
to higher selectivities (entry 4 and 5). The –NO2 substituted
benzyl alcohol exhibited only 27% selectivity of ester product.
According to this results, when alcohols were used as starting
materials, they exhibited the lower catalytic activity in com-
parison to using aldehydes as starting materials. This might be
due to the low coordination between hydroxyl group and active
Co NPs or Co–Nx sites in the catalyst, therefore, the small
amount of alcohol molecules could adsorb on catalyst surface.
Based on the above results and taking into the previous
reports [8, 45, 65–67], the proposed reaction mechanism for
1 3

The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative…
Table 2 Oxidative esterifcation of benzaldehyde derivatives and
catalyst was only 10% conversion and 3% selectivity of ester
product, eventhough the reaction time was prolong to 24 h.
Meanwhile, the much higher %conversions and %selectivities
of ester product were obtained in the presence of catalyst.
This indicated that, this prepared Co catalyst is essential for
this reaction. Therefore, in the frst step, the active Co–Nx
sites in the catalyst could adsorb benzaldehyde through oxy-
gen atom from carbonyl group, promoting the electrophilic
properties of aldehydes, following nucleophilic attacking
from methanol yielding hemiacetal species. Then, the hemi-
acetal intermediate transforms directly to an ester product
over the catalyst surface with using O2 as an oxidant. For this
step the Co–Nx sites could capture the molecular O2 under
the assistance of the doped nitrogen to form metal alcoholate
specie 1, then β-hydride elimination which is promoted by
K2CO3, takes place to form the ester product. Meanwhile,
further condensation between the hemiacetal and methanol
can occur, and thus the acetal byproduct was also observed.
methanol over Co-MOFs-800 catalyst
Entry Substrates
1
Time (h) Conv. (%) Sel. (%)
12
12
98
84
100
91
O
H
2
O
H
H3CO
3
O
12
12
12
97
100
97
100
100
100
H
H3C
4
O
H
O2N
3.3 Reusability Test
5
O
To demonstrate the stability and reusability of Co-
MOFs-800 catalyst, we have checked the recycling of the
catalyst by using benzaldehyde as a model substrate. After
completion of the reaction, the catalyst was easily recovered
from reaction mixture by using external magnet, washed
with methanol and then dried. The recovered catalyst was
used for fve subsequent runs under similar reaction con-
ditions. The results of recycling experiments were shown
in Fig. 8. The %selectivity of the methyl benzoate product
remained in all cases. This confrmed that the developed
catalyst was quite stable and could be reused efciently with-
out any signifcant loss in activity. Furthermore, the cobalt
content in the recovered catalyst after the ffth run was found
to be almost similar (31.6 wt%) as in the fresh catalyst (32.3
wt%) as determined by ICP-AES analysis. The XRD result
and TEM images of the used catalyst was also similar to the
fresh catalyst, confrming the high stable of our prepared
catalyst (Figs. S4 and S5 in the Supporting Information)
H
NC
6
7
8
12
20
12
75
82
85
100
100
100
NO2
O
O
H
H
NO2
O
H
Cl
9
12
12
99
96
100
100
O
H
Br
10
O
4 Conclusions
H
F
The cobalt-based metal organic frameworks (Co-MOFs)
catalyst has been prepared for the oxidative esterifcation
using molecular oxygen as benign oxidant under mild condi-
tions. The Co nanoparticles pyrolysed at diferent tempera-
tures showed diferent catalytic activities. The Co-MOFs
pyrolysed at 800 °C (denoted as Co-MOFs-800) exhibited
superior catalytic activity toward the oxidative esterifca-
tion of benzaldehyde and benzaldehyde derivatives to the
corresponding methyl ester products, which is ascribed to
the synergistic catalytic efect between Co NPs and Co–Nx
Reaction conditions: Co-MOFs-800 catalyst (20 mg), benzalde-
hyde derivatives (1 mmol), methanol (5 mL), K2CO3 (0.5 mmol), O2
(1 MPa), 60 °C reaction temperature
the oxidative esterifcation of benzaldehyde over metallic Co
supported N-doped carbon derived from Co-MOFs (Co@
NC) was illustrated in Scheme 1. According to the result in
Table 1 (entry 11), the catalytic activity in the absence of
1 3

P. Mekrattanachai et al.
Table 3 Oxidative esterifcation
of various alcohols and
methanol over Co-MOFs-800
catalyst
Entry Substrates
Time (h) Conv. (%)
Sel. (%)
Sel. (%)
O
O
CH3
O
H
R
R
1
2
24
24
53
78
0
100
22
OH
78
OH
H3C
3
24
96
55
45
OH
H3CO
4
24
24
24
50
54
69
82
100
27
18
0
OH
Br
5
OH
Cl
6
73
OH
O2N
Reaction conditions: Co-MOFs-800 catalyst (20 mg), alcohol (1 mmol), methanol (5 mL), K2CO3
(0.5 mmol), O2 (1 MPa), 60 °C reaction temperature
Scheme 1 Mechanism pro-
posed for the oxidative esteri-
fcation of benzaldehyde over
metallic Co supported N-doped
carbon derived from Co-MOFs
(Co@NC)
1 3

The Highly Efective Cobalt Based Metal–Organic Frameworks Catalyst for One Pot Oxidative…
Fig. 8 Reusability of Co-
MOFs-800 catalyst in the
oxidative esterifcation of ben-
zaldehyde. Reaction conditions:
catalyst (40 mg), benzaldehyde
(2 mmol), methanol (10 mL),
K
2CO3 (1 mmol), 60 °C, O2
(1 MPa), 3 h reaction time
8. Jun G, Guoli F, Lan Y, Xinzhong C, Peng Z, Feng L (2017) Chem
Cat Chem 9:1230–1241
active sites in the prepared catalyst. Furthermore, our pre-
pared Co-MOFs-800 catalyst could be reused at least fve
consecutive runs without signifcant loss of activity, con-
frming the high stability of this prepared catalyst.
9. Yajuan H, Yanzhu C, Shuru L, Hengquan Y (2012) J Phys Chem
C 116:6512–6519
10. Ramakrishnan R, Kathiravan K, Sakthivel K, Sivakumar T (2016)
RSC Adv 6:45907–45922
11. Chih Hsiang T, Mengze X, Pranaw K, Brian TG (2018) Catal
Today 306:81–88
Supplementary Information The online version of this article (https://
doi.org/10.1007/s10562-021-03754-x) contains supplementary mate-
rial, which is available to authorized users.
12. Singh S, Patel A, Prakashan P (2015) Appl Catal A 505:131–140
13. Li Y, Wang L, Yan R, Han J, Zhang S (2015) Catal Sci Technol
5:3682–3692
Acknowledgements The authors are grateful to the fnancial sup-
ports from the National Natural Science Foundation of China (NSFC
21333009, 21573244, 21573245), Chinese Academy of Sciences-
Peking University Pioneer Cooperation Team and the Youth Innovation
Promotion Association of CAS (2017049).
14. Wan X, Deng W, Zhang Q, Wang Y (2014) Catal Today
233:147–154
15. Suzuki K, Yamaguchi T, Matsushita K, Iitsuka C, Miura J, Akaogi
T, Ishida H (2013) ACS Catal 3:1845–1849
16. Sanny V, Deepak V, Anil SK, Suman JL (2015) Appl Catal A
489:17–23
Declarations
17. Yasukawa T, Yang X, Kobayashi S (2018) Org Lett 20:5772–5776
18. Xie J, Kammert JD, Kaylor N, Zheng JW, Choi E, Pham HN,
Sang X, Stavitski E, Attenkofer K, Unocic RR, Datye AK, Davis
RJ (2018) ACS Catal 8:3875–3884
Conflict of interest There are no conficts to declare.
19. Cui X, Li Y, Bachmann S, Scalone M, Surkus AE, Junge K, Topf
C, Beller M (2015) J Am Chem Soc 137:10652–10658
20. Su H, Zhang KX, Zhang B, Wang HH, Yu QY, Li XH, Antonietti
M, Shen JS (2017) J Am Chem Soc 139:811–818
21. Feng Y, Jia W, Yan GH, Zeng XH, Sperry J, Xu BB, Sun Y, Tang
X, Lei TZ, Lin L (2020) J Catal 381:811–818
References
1. Ogawa T, Matsui M (1976) J Am Chem Soc 98:1629–1630
2. Wilson SR, Tofgh S, Misra RN (1982) J Org Chem 47:1360–1361
3. Garegg PJ, Olsson L, Oscarson S (1995) J Org Chem
60:2200–2204
22. Eisenberg D, Slot TK, Rothenberg G (2018) ACS Catal
8:8618–8629
23. Slot TK, Eisenberg D, Rothenberg G (2018) Chem Cat Chem
10:2119–2124
4. Otera J, Nishikido J (2010) Esterifcation; methods, reactions, and
applications, 2nd edn. Wiley-VCH, Weinheim
5. Smith MB, March J (1992) March’s advanced organic chemistry.
Wiley, New York
24. Astrakova TV, Sobolev VI, Koltunov KY (2020) Catal Commun
137:105952
25. Cheng TY, Yu H, Peng F, Wang HG, Zhang BS, Su DS (2016)
Catal Sci Technol 6:1007–1015
6. Ning L, Liao S, Liu X, Guo P, Zhang Z, Zhang H, Tong X (2018)
J Catal 364:1–3
26. Jagadeesh RV, Junge H, Pohl MM, Radnik J, Bruckner A, Beller
M (2013) J Am Chem Soc 135:10776–10782
7. Fan C, Wang R, Kong P, Wang X, Wang J, Zhang X (2020) Catal
Commun 140:106002
1 3

P. Mekrattanachai et al.
48. Alireza A, Mohammad S, Mahnaz N, Shokoofeh G (2017) J Mol
Struct 1133:458–463
27. Tang C, Surkus AE, Chen F, Pohl MM, Agostini G, Schneider M,
Junge H, Beller M (2017) Angew Chem Int Ed 56:16616–16620
28. Wang X, Zhou J, Fu H, Li W, Fan X, Xin G, Zheng J, Li X (2014)
J Mater Chem A 4:14064–14070
49. Xu Y, Li B, Zheng S, Wu P, Zhan J, Xue H, Xu Q, Pang H (2018)
J Mater Chem A 6:22070–22076
50. Chao L, Taiqiang C, Weijing X, Xiaobing L, Likun P, Qun C,
Bingwen H (2015) J Mater Chem A 3:5585–5591
51. Tao J, Tong ML, Chen XM (2000). J Chem Soc Dalton Trans.
https://doi.org/10.1039/b005438k
29. Li X, Jiang Q, Dou S, Deng L, Huo J, Wang S (2016) J Mater
Chem A 4:15836–15840
30. Zheng W, Jiang X, Wang X, Kaneti YV, Chen Y, Liu J, Jiang JS,
Yamauchi Y, Hu M (2017) Angew Chem Int Ed 56:8435–8440
31. Jiewei L, Lianfen C, Hao C, Jianyong Z, Li Z, Cheng Yong S
(2014) Chem Soc Rev 43:6011–6061
52. Xu H (2008) Acta Cryst E64:m103
53. Kathiravan M, Thirusangumurugan S, Manzar S, Ahmad
AS, Marga PM, Matthias B, Rajenahally JV (2018) Chem Sci
9:8553–8560
32. Chen L, Chen H, Luque R, Li Y (2014) Chem Sci 5:3708–3714
33. Sun CY, To WP, Wang XL, Chan KT, Su ZM, Che CM (2015)
Chem Sci 6:7105–7111
54. Heejun P, Sojin O, Sujeong L, Sora C, Moonhyun O (2019) Appl
Catal B 246:322–329
34. Gong YN, Ouyang T, He CT, Lu TB (2016) Chem Sci
7:1070–1075
55. Li W, Geng W, Liu L, Shang Q, Liu L, Kong X (2020) Sustain
Energy Fuels 4:2043–2054
35. Adeel CH, Nazir A, Hussein YA, Laypkovc A, Francis V (2015)
Chem Soc Rev 44:6804–6849
56. Wang Z, Xiao S, Zhu Z, Long X, Zheng X, Lu X, Yang S (2015)
ACS Appl Mater Interfaces 7(7):4048–4055
36. Huang YB, Liang J, Wang XS, Cao R (2017) Chem Soc Rev
46:126–157
57. Liu Y, Jiang H, Zhu Y, Yang X, Li C (2016) J Mater Chem A
4:1694–1701
37. Xuning L, Xiang H, Shibo X, Shu M, Jie D, Weizheng C, Song
L, Xiaoli Y, Hongbin Y, Jiajian G, Junhu W, Yanqiang H, Tao Z,
Bin L (2018) J Am Chem Soc 140:12469–12475
38. Huirong C, Kui S, Junying C, Xiaodong C, Yingwei L (2017) J
Mater Chem A 5:9937–9945
58. Liua Y, Wanga C, Jua S, Lia M, Yuana A, Zhu G (2020) Prog Nat
Sci Mater 30:185–191
59. Wang T, Ma H, Liu X, Luo Y, Zhang S, Sun Y, Wang X, Gao J,
Xu J (2019) Chem Asian J 14:1515–1522
60. Bai C, Li A, Yao X, Liu H, Li Y (2016) Green Chem
18:1061–1069
39. Ming Z, Chaohai W, Chao L, Rui L, Jiansheng L, Xiuyun S, Jinyou
S, Weiqin H, Lianjun W (2018) J Mater Chem A 6:11226–11235
40. Feng J, Hailing G, Lei Z, Junjuan L, Yongming C, Svetlana M,
Chenguang L (2019) Microporous Mesoporous Mater 276:98–106
41. Guowu Z, Hua Chun Z (2017) ACS Catal 7:7509–7519
42. Guihao Z, Dingxin L, Jianyong Z (2018) J Mater Chem A
6:1887–1899
61. Liu M, Zhang H, Wang J, Zhao G, Liu D (2020) React Kinet Mech
Catal 129:865–881
62. Vineeta P, Amer NA, Ahmed A, Brigitte S, Pascal R, Rabah B,
Suman JL (2015) RSC Adv 5:88567–88573
63. Hui S, Ke ZX, Bing Z, Hong WH, Qiu YY, Xin LH, Markus A,
Jie CS (2017) J Am Chem Soc 139:811–818
43. Guangli Y, Jian S, Faheem M, Pengyuan W, Guangshan Z (2014)
RSC Adv 4:38804–38811
64. Rui T, Lu GP, Zhao X, Chen Z (2021) Chin Chem Lett 32:685–690
65. Salazar A, Hunemorder P, Rabeah J, Quade A, Jagadeesh RV,
Mejia E (2019) ACS Sustain Chem Eng 7:12061–12068
66. Zhou C, Tan Z, Jiang H, Zhang M (2018) Green Chem
20:1992–1997
44. Wei Z, Hongli L, Cuihua B, Shijun L, Yingwei L (2015) ACS
Catal 5:1850–1856
45. Yu Xiao Z, Yu Zhen C, Lina C, Junling L, Hai Long J (2015)
Chem Commun 51:8292–8295
67. Jiang BL, Lin Y, Wang ML, Liu DS, Xu BH, Zhang SJ (2019) Org
Chem Front 6:801–807
46. Sun KK, Chen SJ, Li ZL, Lu GP, Cai C (2019) Green Chem
21:1602–1608
47. Feng Y, Jia W, Yan G, Zeng X, Sperry J, Xu B, Sun Y, Tang X,
Lei T, Lin L (2020) J Catal 381:570–578
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