Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for Synthesis of 3-Aryl-2-oxazolidinones from Alkenes, Amines, and Carbon Dioxide

Article abstract of DOI:10.1007/s10562-019-03073-2

Abstract: In the present research, a new dendritic fibrous nanosilica (DFNS) based nanocatalyst (DFNS/Dy₂Ce₂O₇) that has high surface zone as well as easy availability of active zones has been properly expanded using an easy approach. DFNS that possess high surface zone is functionalized by amino groups working as the anchors such that the nanoparticles of Dy₂Ce₂O₇ are fine-dispersed onto the DFNS microspheres fibres, without any aggregation. The nanoparticles of Dy₂Ce₂O₇ are produced by a green approach in the attendance of gum of ferula assa-foetida of Dy(NO₃)₃ and (NH₄)₂Ce(NO₃)₆ as ceric and dysprosium sources. The structural evaluation of the samples proved the synthesis of Dy₂Ce₂O₇ NPs. Moreover, a straight way for the production of 3-aryl-2-oxazolidinones by carbon dioxide, olefins, and anilines was obtained utilizing nano catalyst of DFNS/Dy₂Ce₂O₇ in the lack of solvent. The reaction works properly at moderate states. This method that is cheap and simple may be used to different olefins that has proper to excellent 3-aryl-2-oxazolidinones productions. The catalyst may be simply recycled for ten times without considerable losing the activity of its catalytic. Graphic Abstract: [Figure not available: see fulltext.]

Full text of DOI:10.1007/s10562-019-03073-2

Catalysis Letters
https://doi.org/10.1007/s10562-019-03073-2
Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous
Nano‑silica for Synthesis of 3‑Aryl‑2‑oxazolidinones from Alkenes,
Amines, and Carbon Dioxide
Li Feng1 · Xuhao Li1 · Chuang Xu1,2 · Seyed Mohsen Sadeghzadeh3
Received: 13 October 2019 / Accepted: 7 December 2019
© Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract
In the present research, a new dendritic fbrous nanosilica (DFNS) based nanocatalyst (DFNS/Dy2Ce2O7) that has high surface
zone as well as easy availability of active zones has been properly expanded using an easy approach. DFNS that possess high
surface zone is functionalized by amino groups working as the anchors such that the nanoparticles of Dy2Ce2O7 are fne-
dispersed onto the DFNS microspheres fbres, without any aggregation. The nanoparticles of Dy2Ce2O7 are produced by a
green approach in the attendance of gum of ferula assa-foetida of Dy(NO3)3 and (NH4)2Ce(NO3)6 as ceric and dysprosium
sources. The structural evaluation of the samples proved the synthesis of Dy2Ce2O7 NPs. Moreover, a straight way for the
production of 3-aryl-2-oxazolidinones by carbon dioxide, olefns, and anilines was obtained utilizing nano catalyst of DFNS/
Dy2Ce2O7 in the lack of solvent. The reaction works properly at moderate states. This method that is cheap and simple may
be used to diferent olefns that has proper to excellent 3-aryl-2-oxazolidinones productions. The catalyst may be simply
recycled for ten times without considerable losing the activity of its catalytic.
Graphic Abstract
O
O
R'
O
Si
O
CO2
NH2
Dy2Ce2O7
NH2
NH2
N
O
R'
Si
O
O
O
R
R
Keywords Nanocatalyst · Green chemistry · Kinetic · Dy2Ce2O7 · Carbon dioxide
2
* Li Feng
f19860314@126.com
State Key Laboratory of Geodesy and Earth’s Dynamics,
Institute of Geodesy and Geophysics, Chinese Academy
of Sciences, Wuhan 430077, China
* Chuang Xu
chuangxugdut@126.com
3
New Materials Technology and Processing Research Center,
Department of Chemistry, Neyshabur Branch, Islamic Azad
University, Neyshabur, Iran
* Seyed Mohsen Sadeghzadeh
seyedmohsen.sadeghzadeh@gmail.com
1
School of Civil and Transportation Engineering, Guangdong
University of Technology, No100, Waihuan Xi Road,
Guangzhou, Higher Education Mega Center, Panyu District,
Guangzhou 510006, Guangdong, China
Vol.:(0123456789)
1 3

L. Feng et al.
starting compounds under the lack of toxic or proper metal
catalysts at moderate conditions of reaction is a synthetic
issue. Epoxides were synthesized by olefns, [9, 37, 38]
one-pot synthesis of oxazolidinones by olefns, amines as
well as carbon dioxide has attracted diferent interesting,
since the reaction utilizes available and also inexpensive
chemicals olefns, and passes the primary production of
epoxides.
1 Introduction
Recently, the chemical fixation of carbon dioxide has
been investigated because of its ubiquitous, unfamable,
low toxicity, reproducible, cheap, and properties, which
indicated excellent conditions to make the Carbon–Nitro-
gen and Carbon–Carbon bonds in organic syntheses.
These carbon dioxide properties can be described about its
kinetic inertness along with great stability. In this regards,
consider able method was achieved. Utilizing carbon diox-
ide for synthesis of various organic compound, such as
alcohol, amides, esters, carboxylic acids, carbamates,
and carbonates. It was suggested by diferent impressive
catalytic methods. About the reaction of carbon dioxide,
signifcant approach is constructed, and various progresses
were expanding to products such as cyclic carbonates,
salicylic acid, urethane, etc. Carbamates as one of these
compounds are known as an important diverse composite.
Therefore, using CO2 to produce diferent organic com-
pound, likeamides, esters, alcohols, carbonates and car-
boxylic acids as well as carbamates [1-5]. Between them,
carbamates such as 3-aryl-2-oxazolidinones are widely
used in agronomy, pharmaceutics, and organic produc-
tion. Recently, for synthesis of 3-aryl-2-oxazolidinones
are used from carbon dioxide, ethylene oxide, and anilines
[6-11]. Being involved in an old reaction, the mentioned
compounds are formed by CO2 or oxiranes [12], while the
transformationis catalyzed by some organic and inorganic
compounds like phosphanes, salen complexes [13], transi-
tion metal complexes [14], Polymeric Ionic Liquids (PILs)
[15], amines, ionic liquid [16], organocatalysts [17] and
organotin halides [18-21].
The functionalization of solid supports such as porous
silica (such as MCM-41 and SBA-15) by various amines is
one of the best ways to create next-generation CO2 sorbent
materials. One of the critical disadvantages was the drastic
decrease in their textural properties (surface area, pore vol-
ume, etc.), and hence, there was not a signifcant improve-
ment in the CO2 capture capacity and kinetics owing to poor
difusion and restricted accessibility of the amine sites [39,
40]. To overcome this challenge, scientists envisioned DFNS
as a possible good support to design efcient CO2 sorbents
[41, 42]. Owing to its fbrous and open structure, it can have
high amine loadings, with minimal reduction in surface area
and, hence, improved accessibility of the amine sites. To
study these hypotheses, functionalization of DFNS by using
various amines was undertaken [43].
Re2Ce2O7 as a rare earth cerate have been highly consid-
ered because of its wide applications in diverse felds [44-
46]. Various approaches are proposed to produce the rare
earth create [47-49]. These approaches are not eco-friendly
viable and also not cost efective because of the applica-
tion of complex cases during preparation and/or harmful
chemical material. Thus, reduction of the detrimental chemi-
cal materials is necessary to provide clean and impressive
method to produce the nano-scale rare earth cerate.
In the present paper, nanoparticles of DFNS/Dy2Ce2O7
have been prepared to decrease the Dy2Ce2O7 consumption
and the immobilization of nanoparticles of Dy2Ce2O7 on the
DFNS to synthesis the nanocatalyst DFNS/Dy2Ce2O7 could
be appropriate for the aim of preventing the Dy2Ce2O7 NPs
aggregation, enhancing the availability of the active sites
and also conferring heterogen separation property for the
nanocatalyst. Firstly, DFNS suggested by Polshettiwar as
the easily accessible high surface area related to its not pores
and also fbers [50]. In addition, a novel, facile way and
low-temperature was suggested to produce Dy2Ce2O7 NPs
by ferula assa-feotida gum. Then, simple direct production
of oxazolidinones is proposed from olefns, and amines as
well as carbon dioxide by nanocatalyst of DFNS/Dy2Ce2O7
at green reaction conditions. Scheme 1 shows that high yield
of products can be obtained and also the catalyst can be
recycled, easily.
Oxazolidinones have been classifed as fve-membered
heterocyclic compounds, which include N2 and O2. Oxazo-
lidinone preparation are properly investigated due to their
usefulness in agricultural industries and organic produc-
tion [22-24]. The common synthetic approach utilizes
isocyanate and phosgene as carbonyl precursors [25-27].
Nevertheless, the toxicity of these beginning compounds is
not suitable for green chemistry. Other diferent synthetic
approaches that utilized cyclic carbonates or carbon diox-
ide as carbonyl precursors at the metal salt presence are
investigated [28-30]. But, most of the provided reactions
consisting the utilize of CO2 as a surrogate of CO have
been conducted at high pressure of CO2 and using some
valuable metal catalysts [31-33]. Between the reported
synthetic approaches, the three-component cycloaddi-
tion of primary amines afording 2-oxazolidinones, car-
bon dioxide, and epoxide [34-36] are considered as the
most promising synthetic approach by developing carbon
dioxide as source of carbon.Thus, identifying a novel way
to oxazolidinone structures utilizing readily attainable
1 3

Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for…
R'
O
CO2
DFNS/Dy2Ce2O7
NH2
N
O
Oxidant
R'
R
R
Scheme 1 Synthesis of 3-aryl-2-oxazolidinones in the presence of DFNS/Dy2Ce2O7 NPs
2.3 General Approach for the Production
of Nanoparticles DFNS‑NH2
2 Experimental
2.1 Materials and Methods
0.2 g DFNS NPs and 20 mL THF are mixed in a beaker.
After wards, 20 mmol NaH is dispersed in within the mix-
ture with 22 mmol ultrasonication. 3-aminopropyltriethox-
ysilane is released drop-wise under the temperature of 25 °C.
Then stirred for around 16 h under the temperature of 60 °C.
The yield of products is collected and washed by deionized
water and ethanol, then dried under the temperature of 60 °C
for around 2 h and under vacuum for further utilization.
High purity chemicals were procured from Fluka and
Merck. Electrothermal 9100 apparatus were utilized for
the determination of uncorrected melting points in open
capillaries. VERTEC 70 spectrometer (Bruker) in trans-
mission mode were used for the determination of FTIR
spectra. Samples were pulverized and pelletized with spec-
troscopic grade KBr. Determination of size and structure
of nano particles were done via transmission electron
microscope (TEM) (Phillips CM10) operated at 100 kV.
The crystallographic structures of nano particles were
determined using powder X-ray difraction (Bruker D8
Advance model) with Cu ka radiation. Thermal gravim-
etry analysis (TGA) (NETZSCH STA449F3) was utilized
under nitrogen atmosphere with a heating rate of 10 °C/
min. Thin later chromatography (TLC) done on silica gel
polygramSILG/UV 254 plates were used for the determi-
nation of product purity and monitoring of reaction. Shi-
madzu GCMS-QP5050 Mass Spectrometer were used to
record the mass spectra.
2.4 General Procedure for the Preparation of DFNS/
Dy2Ce2O7 NPs
H2N-DFNS (0.1 g) and aqueous (1.1 ml) ceric ammonium
nitrate and also 45 mM dysprosium nitrate are dissolved into
distilled H2O. After that citric acid (0.002 mol) are added in
the mixed solution. The pH of the upper mentioned solution
is adjusted to 9 using tetraethylenepentamine (TEPA) drop-
wise, in the next step ethylene glycol (0.002 mol) as agent of
esterifcation is released the resultant solution. By increasing
temperature along with evaporation of the gel-like solution
causes the synthesis of porous solid mass. The ferula assafe-
otida gum (1 g) is mixed with obtained powders and are
calcinated under the temperature of 700 °C for around 3 h.
2.2 General Approach for the Production
of Nanoparticles of DFNS
In a solution that contains 30 mL of cyclohexane along
with 1.5 mL of 1-pentanol, 2.5 g Tetraethyl orthosilicate
is dissolved. After that a stirred cetylpyridinium bromide
(1 g) and urea (0.6 g) solution is added in 30 mL of H2O.
The obtained mixture aws stirred, continually, for 45 min
under temperature of 25 °C thenset within a tefon-sealed
hydrothermal reactor and heated under the temperature of
120 °C for around 5 h. By centrifugation silica formed is
isolated and after that washed by a mixture of deionized
acetone and water then dried within a drying oven. Under
the temperature of 500 °C and air, it is calcined for around
6 h.
2.5 Catalytic Reactions
The reaction was conducted in a 25 mL stainless autoclave.
DFNS/Dy2Ce2O7 as a catalyst (5 mg), olefn (10 mmol),
TBHP (20 mmol) were added into the stainless autoclave.
The mixture was stirred by a magnetic stirrer and heated to
desired temperature in a water bath. The aniline (1.0 mmol)
were charged into the stainless autoclave. The reactor was
purged with CO2 for three times and then charged with CO2.
Next, the stainless autoclave was heated to desirable tem-
perature and stirred for 10 h. After the reaction is completed,
1 3

L. Feng et al.
the autoclave was cooled to room temperature, and the
remaining CO2 is slowly discharged from the reactor. The
reaction solution was analyzed by using GC and GC–MS.
as association centers for the Dy2Ce2O7 NPs growth on the
site of DFNS fbers. Figure 1 shows the schemes of TEM
and SEM in the case of the H2N-DFNS, DFNS/Dy2Ce2O7,
and DFNS catalysts. As observe in Fig. 1a, d, the nanopar-
ticles of DFNS possessed a frm particle size range around
200 nm. Consequently, in order to form core–shell particles
of H2N-DFNS (refer to Fig. 1b, e) hyperbranched 3-APTES
is coated onto the DFNS. In addition, the metal NPs are
distinguishable, obviously, by the diversity in their contrast
after anchoring the Dy2Ce2O7. The as-prepared NPs of
metal are spherical without considerable aggregation. The
NPs morphology is near-wall Dy2Ce2O7 and NPs diameter
is around 10 nm (Fig. 1c, f).
3 Results and Discussion
Scheme 2 shows that for production of nanocatalysts of
DFNS/Dy2Ce2O7 several stages should be performed. The
DFNS fbers have many groups of Si–OH bond on the sites.
Therefore, to form H2N-DFNS, we can expect that the DFNS
can be functionalized by (3-Aminopropyl)triethoxysilane
(3-APTES). In addition, the amino groups that are on the
H2N-DFNS can use as association centres in the case of
the development of Dy2Ce2O7 NPs on the DFNS site. For
synthesizing Dy2Ce2O7 (nano-scale) an environmentally
friendly and easy way can beused that is extract of gum
from ferula assafeotida as impressive and novel bio fuel.
The amount of extracted Ananas comosus is changed to fg-
ure out its infuence on dimension of Dy2Ce2O7, shape, and
catalytic yield.
The XRD analysis, which can be highly beneficial
method for detecting mean crystallite size and crystalline
structure, is utilized to examine the as-obtained nanostruc-
tured Dy2Ce2O7. The broad peak that is between the range
of 20–30° relates to amorphous silica. Figure 2 shows total
the difraction peaks [51]. As can be seen, all of them are
matched, properly, with pure fuorite Dy2Ce2O7 and also
there are no impurities [52].
The DFNS fbers has many Si–OH bonds on the sites.
Hence, we expected that the DFNS fbers can be function-
alized, easily, by 3-APTES to make H2N-DFNS. In addi-
tion, the groups of amino on the H2N-DFNS canbe used
The Fig. 3 shows the FTIR scheme of DFNS and also
H2N-DFNS. The bands between 3200–3500 and 1663 cm−1
were related to the Si–OH stretching and molecules of water
absorbed on the DFNS site, respectively. Figure 3a presents
O
O
Si
O
EtO
EtO Si
EtO
NH2
NH2
NH2
Si
O
O
O
(DFNS)
Compound 1
(NH4)2Ce(NO3)6
Dy(NO3)3
O
O
Si
O
OEt
Si
NH2
EtO
OEt
Dy2Ce2O7
NH2
OEt
Si
O
O
O
Compound 2
Scheme 2 Schematic illustration of the DFNS/Dy2Ce2O7 NPs preparation
1 3

Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for…
Fig. 1 SEM images of DFNS (a); H2N-DFNS (b); DFNS/Dy2Ce2O7 (c); TEM images of DFNS (d); H2N-DFNS (e); DFNS/D y2Ce2O7 (f)
Dy2Ce2O7 is demonstrated in Fig. 5. As observed, raw DFNS
have no considerable weight loss. Hence, functionalized
carbon nanotubes demonstrate a weight loss by about 4%
under 150 °C temperature resulted from deletion adsorbed
H2O. The elimination of the chemisorbed and physisorbed
solvent on the DFNS/Dy2Ce2O7 material site causing the
weight loss. Moreover, weight loss between temperature of
250–450 °C is near to 17.6 wt%, which is related the organic
group derivatives. Decreasing the weight in the upper men-
tioned temperature rate may be because of using removal of
3-Aminopropyl.
BET specifc surface area of DFNS, and DFNS/Dy2Ce2O7
Fig. 2 XRD analysis of fbrous DFNS/Dy2Ce2O7 NPs
were determined via nitrogen physisorption analysis and
found to be 631, and 309m2/g, respectively. In comparison to
the Si–O–Si band close to 1095 and 799 cm−1 along with
a condensed silica network formation. Figure 3b indicates
the peak at 2925 cm−1 appearing in the H2N-DFNS in com-
parison to the DFNS spectrum according to the stretching
vibration saturated bond of C–H on the aminopropyl groups
(Fig. 3b) [53-55].
DFNS, DFNS/Dy2Ce2O7 experienced a reduction in surface
area. This may be due to the supporting of Dy2Ce2O7 in the
DFNS. Also, the reduction of surface area was more obvious
in DFNS/Dy2Ce2O7 NPs because of poor bicontinuous con-
centric Dy2Ce2O7 morphology of the nanocatalyst. Figure 6
showed that the nitrogen adsorption–desorption isotherms of
DFNS based catalysts. The presence of mesopores in DFNS
is confrmed with the presence of IV isotherm and H1-type
hysteresis loop. The desorption branch of nitrogen isotherm
is used for the calculation of pore size distribution by BJH
method. As tabulated in Table 1, it is found that corre-
sponding pore size distribution exhibited a narrow pore size
The roughness of nanoparticles surface of H2N-DFNS is
specifed using analysis of atomic force microscopy (AFM)
(refer to Fig. 4). As can be observed, the greater height zone
showed by the brighter yellowish white color enhanced by
decreasing T/W, suggesting the improve in the roughness of
catalyst surface. TG analysis of the nano particles of DFNS/
1 3

L. Feng et al.
Fig. 3 FTIR spectra of a DFNS
NPs, and b H2N-DFNS NPs
Fig. 4 Three-dimensional of AFM images of fbrous H2N-DFNS NPs
Fig. 5 TGA curve of raw DFNS (a); and DFNS/Dy2Ce2O7 NPs (b)
distribution peaked at 10 nm (Table 1). The great mesopore
size of DFNS with great capacity can load Dy2Ce2O7 that
have relative large molecular size.
DMSO, and EtOAc (polar aprotic solvents). In the present
work, solvents are determined to have less performance
in comparison tousual heating at solvent-free conditions.
The mean carbonylative cross-coupling yields are isolated
whenever a low production is achieved in polar solvents
while the reaction is performed in less polar solvents like
anisole and/or toluene. At the presence of nanoparticles
of DFNS/Dy2Ce2O7 (10 mg) under the optimal conditions,
by using GC apparatus, the reaction progress is analysed
to obtainthe shortest necessary time. It was determined
that excellent yields of product (3-aryl-2-oxazolidinone
synthesis) are obtained at 20 h.
In this system, the conditions of reaction are optimized
using aniline, carbon dioxide, and olefn usages for 3-aryl-
2-oxazolidinone synthesis catalysed by nanoparticles of
DFNS/Dy2Ce2O7. In the Table 2, the model reaction is
presented the efects of various factors such as time and
solvent. Diferent solvents were used to investigate their
infuences on the production of 3-aryl-2-oxazolidinone.
The outcome sindicated that no synthesises of the prod-
uct to polar protic solvents, such as isopropanol, water,
methanol, and ethanol. The cross-coupling yield of prod-
uct indicated a relatively mean production with DMF,
1 3

Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for…
Fig. 6 adsorption–desorption isotherms of the DFNS NPs (a); and DFNS/Dy2Ce2O7 NPs (b); BJH pore size distributions of the DFNS NPs (c);
and DFNS/Dy2Ce2O7 NPs (d)
Table 1 Structural parameters of DFNS, and DFNS/Dy2Ce2O7 NPs
model reaction can be obtained in the attendance of DFNS/
Dy2Ce2O7NPs (5 mg).
Catalysts
SBET (m2 g−1
)
Va (cm3 g−1
)
DBJH (nm)
Figure 8 shows the efect of temperature on the reaction.
As can be observed, the 3-aryl-2-Oxazolidinone production
increased to around 98% at the 50 °C temperature and under
3.0 MPa CO2 pressure for 20 h. Whereas more increase
in this temperature led to a slight decrease in the yield of
product due to making a negligible quantity of certain by
products such as the isomerization of olefn. Therefore, the
optimal temperature in the case of the parallel reaction of
olefn, aniline, carbon dioxide is near to 50 °C temperature.
The CO2 pressure has a considerable impact on the parallel
reaction. As can be seen in Fig. 9, the reaction rate is rapidly
enhanced in the pressures between 2.0 and 2.5 MPa. From
previous studies, it can be resulted that increasing reaction
pressure isdesirable to produce 3-aryl-2-Oxazolidinone
when the reaction pressure isbelow 2.5 MPa. Therefore, the
CO2 pressure of 2.5 MPa is found as specifc condition. At
DFNS
DFNS/Dy2Ce2O7
631
309
3.8
1.6
10
5
The efects of various reaction parameters have been
investigated to enhance reaction states for the catalyst nan-
oparticles of DFNS/Dy2Ce2O7. As can be seen in Fig. 7,
the catalyst amount was considered as another consider-
able parameter in reaction of the 3-aryl-2-Oxazolidinone-
may synthesis. In addition, the low yield of product of the
cycloaddition reaction was achieved whereas model reaction
was performed in the absence of a catalyst. Moderate 3-aryl-
2-Oxazolidinone may products were obtained while nano-
particles of DFNS/Dy2Ce2O7 (1–4 mg) were weighted onto
sample reaction. It was determined that the most appropriate
1 3

L. Feng et al.
100
90
80
70
60
50
40
30
20
10
0
Table 2 Synthesis of 3-aryl-2-oxazolidinone by DFNS/Dy2Ce2O7
NPs in diferent solvents
Entry
Solvent
Time (h)
Yield (%)a
1
2
3
4
5
6
7
8
MeOH
EtOH
i-PrOH
H2O
n-Hexane
Dioxane
THF
DMF
CH2Cl2
CHCl3
DMSO
CH3CN
EtOAc
Toluene
anisole
solvent-free
solvent-free
solvent-free
solvent-free
solvent-free
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
25
20
15
10
-
-
-
-
-
-
27
32
29
35
30
26
41
43
45
98
98
98
90
32
30
35
40
45
50
55
60
Temperature (oC)
9
10
11
12
13
14
15
16
17
18
19
20
Fig. 8 Efect of temperature on yield of 3-aryl-2-Oxazolidinone
100
90
80
70
60
50
40
30
20
10
0
Reaction conditions: appropriate CO2 (3.0 MPa), aniline (1.0 mmol),
olefn (10 mmol), DFNS/Dy2Ce2O7 NPs (10 mg), TBHP (20 mmol),
and solvent (10 mL), under refux or 100 °C
0
0.5
1
1.5
2
2.5
3
3.5
4
CO2 Pressure (MPa)
aIsolated yields
Fig. 9 Efect of CO2 pressure on the synthesis of 3-aryl-2-Oxazolid-
100
90
80
70
60
50
40
30
20
10
0
inone
0
1
2
3
4
5
6
7
Catalyst amount (mg)
Fig. 7 Efect of increasing amount DFNS/Dy2Ce2O7 NPs on yield of
3-aryl-2-Oxazolidinone
the beginning, the following conditions of reaction areuti-
lized: oxidants under 50 °C at 20 h (10 mol%). Diferent
oxidants such as TBHP, H2O2, Oxone, and UHP as well as
O2 are utilized to increase the yield. The yield of reaction is
greatly sensitive to the base. Accordantly, catalyst basicity is
not the sole parameter in specifying the activity. As senn in
Fig. 10, between oxidants, the best production is illustrated
for TBHP.
Fig. 10 The screening of the oxidant nature
1 3

Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for…
Table 3 Cycloaddition of CO2
O
with terminal olefns and aniline
N
O
DFNS/Dy2Ce2O7
Oxidant
CO2
+
+
NH2
R
R
O
O
O
N
O
N
O
N
O
Me
98 %
90 %
93 %
Me
O
O
O
N
O
N
O
N
O
Cl
97 %
Cl
91 %
99 %
Cl
Reaction conditions: appropriate CO2 (2.5 MPa), aniline (1.0 mmol), olefns (10 mmol), DFNS/
Dy2Ce2O7 NPs (5 mg), and TBHP (20 mmol), under 50 °C
We determined the domain of this transformation by the
fltration experiment for synthesis of 3-aryl-2-Oxazolidinone
at premium states and determined that the catalyst is mag-
netically deleted in situ after around 32% for 10 h removal.
In addition, the reactants are permissible to tolerate more
reaction. The outcomes demonstrated that, after removing
the heterogeneous catalyst, the free catalyst remnant is feeble
active, and the conversion about 34% is obtained after 20 h
of the synthesis of 3-aryl-2-Oxazolidinone. It proved that
the catalyst worked heterogeneously during the reaction and
resentful just slight leaching donein the reaction. Secondly,
for ensuring the heterogeneous pattern of the catalyst, the
mercury poisoning examine is additionally performed. Mer-
cury (0) is imbibed as a metal or using synthesis and dra-
matically deactivated the metal catalyst on active surface and
so tranquilized the catalyst activity. Conducted experiment is
proof of the heterogeneous catalyst. This test has been per-
formed with the aforesaid model of reaction under optimal
states. After 10 h of the reaction, about 300 molar mercury
is released to the reaction compound. The reaction zone is
stirred for above 20 h. In this reaction, no further conversion
is seen after 20 h from the catalyst being poisoned. A kinet-
ics scheme of the reaction under the attendance of Hg(0) is
demonstrated in Fig. 13. The negative outcomes obtained
from the whole heterogeneity experiments (Hg(0) poison-
ing as well as hot fltration) proposed that the solid catalyst
is really heterogeneous and no acquirable metal leaching
performed upon synthesis of 3-aryl-2-Oxazolidinone.
optimal reaction conditions as stated in Table 3. The aryl
olefns nature is frstly explored. In addition, aryl olefns
that bearing a para-chloro group is great substrates, ofering
near-quantitative products. Aryl olefns along with group of
meta- or ortho-chloro are currently great substrates. While
an electron donating group like methyl, is showed to the aryl
group, the production reduced. Therefore, the production is
signifcantly dependent on the electronic infuences of the
aryl olefns. In Table 4, the scope of reaction for aniline
substrates is presented. Diferent amines bearing either elec-
tron-donating (Me, Bu, OMe) and orelectron-withdrawing
(Cl, I, NO2, Br) meta- or para-substituents are exanimated.
Generally, in the reaction, 91–97% amines bearing electron-
donating and 88–93% electron-withdrawing replacements
exclusion of 80% para-nitroaniline are tolerated.
Figure 11 indicated that the catalyst is reused for 10
th consecutive runs. The yield of 3-aryl-2-Oxazolidinone
obtained 95% at the ten run that means only a 3% drop in
performanceis seen in comparison to the related fresh cata-
lyst (98%). In addition, the value of metal leached within the
solution for synthesis of 3-aryl-2-Oxazolidinone after each
runis evaluated using ICP. The catalyst indicated very little
leaching in each turn that 0.6% metal leaching discovered
after the ten run, so showing its consistency at the reaction
states as illustrated in Fig. 12.
In addition, a complete study is performed to clarify
the catalyst heterogeneous nature. Firstly, we done the hot
1 3

L. Feng et al.
Table 4 Cycloaddition of CO2
R'
O
with various amines olefn
N
O
DFNS/Dy2Ce2O7
CO2
+
+
R'
NH2
Oxidant
O
O
O
O
Bu
Me
MeO
N
O
N
O
N
91 %
97 %
96 %
O
O
O
O
O
O2N
Cl
I
N
O
N
O
N
O
80 %
89 %
92 %
O
O
Br
N
O
N
O
N
O
O
Br
Br
90 %
93 %
88 %
O
F
F3C
N
O
N
O
N
O
O2N
91 %
86 %
81 %
Reaction conditions: appropriate CO2 (2.5 MPa), anilines (1.0 mmol), olefn (10 mmol), DFNS/
Dy2Ce2O7 NPs (5 mg), and TBHP (20 mmol), under 50 °C
0.6
0.5
0.4
0.3
0.2
0.1
0
100
90
80
70
60
50
40
30
20
10
0
0
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
Reuse
Reuse
Fig. 11 The reusability of catalysts for synthesis of 3-aryl-2-Oxazo-
Fig. 12 Recyclability of the catalyst for synthesis of 3-aryl-2-Oxazo-
lidinone
lidinone
1 3

Green synthesis of Dy2Ce2O7 Nanoparticles Immobilized on Fibrous Nano-silica for…
6. Niemi T, Perea-Buceta JE, Fernandez I, Hiltunen OM, Salo V,
Rautiainen S, Raisanen MT, Repo T (2016) Chem Eur J 22:1–6
7. Lv M, Wang P, Yuan D, Yao Y (2017) ChemCatChem
9:4451–4455
8. Wang B, Luo Z, Elageed EHM, Wu S, Zhang Y, Wu X, Xia F,
Zhang G, Gao G (2016) ChemCatChem 8:830–838
9. Wang B, Elageed EHM, Zhang D, Yang S, Wu S, Zhang G, Gao
G (2014) ChemCatChem 6:278–283
10. Chen F, Li M, Wang J, Dai B, Liu N (2018) J CO2 Util
28:181–188.
11. Xie YF, Guo C, Shi L, Peng BH, Liu N (2019) Org Biomol
Chem 17:3497–3506
12. Shaikh AAG, Sivaram S (1996) Chem Rev 96:951–976
13. North M, Pasquale R (2009) Angew Chem Int Ed 48:2946–2948
14. Yan P, Jing HW (2009) Adv Synth Catal 351:1325–1332
15. Baba A, Nozaki T, Matsuda H (1987) Bull Chem Soc Jpn
60:1552–1554
16. North M, Young C (2011) Catal Sci Technol 1:93–99
17. Supasitmongkol S, Styring P (2014) Catal Sci Technol
4:1622–1630
Fig. 13 Reaction kinetics, Hg (0) poisoning, and hot fltration studies
for synthesis of 3-aryl-2-Oxazolidinone
18. Elmas S, Subhani MA, Harrer M, Leitner W, Sundermeyer J,
Mueller TE (2014) Catal Sci Technol 4:1652–1657
19. Pena Carrodeguas L, Gonzalez-Fabra J, Castro-Gomez F, Bo C
(2015) Chem Eur J 21:6115–6122
4 Conclusions
20. Montoya CA, Paninho AB, Felix PM, Zakrzewska ME, Vital
J, Najdanovic-Visak V, Nunes AVM (2015) J Supercrit Fluid
100:155–159
Synthesis of Dy2Ce2O7NPs on the DFNS microspheres fb-
ers by utilizing ferula assa-feotidagum that is recently sug-
gested as novel and impressive bio fuel is proved to be an
environmental friendly approach. The DFNS/Dy2Ce2O7
were active not the 3-aryl-2-Oxazolidinone synthesis for the
epoxidation and for the 3-aryl-2-Oxazolidinone synthesis.
This novel catalytic approach may be developed for other
substrates. In comparison with systems that have two distinct
catalysts, the bifunctional catalysts stated here is simple to
be reused without considerable removing its catalytic reac-
tivity. In the case of green chemistry, the straight produc-
tion of 3-aryl-2-oxazolidinones of carbon oxide, olefns, and
anilines catalyzed using the cheap DFNS/Dy2Ce2O7 system
with solvent free condition could possess excellent applica-
tion possible.
21. Macherla VR, Liu J, Sunga M, White DJ, Grodberg J, Teisan S,
Lam KS, Potts BC (2007) J Nat Prod 70:1454–1457
22. Mukhtar TA, Wright GD (2005) Chem Rev 105:529–542
23. Barbachyn MR, Ford CW (2003) Angew Chem Int Ed
42:2010–2023
24. Dyen ME, Swern D (1967) Chem Rev 67:197–246
25. Murdock KC (1968) J Org Chem 33:1367–1371
26. Babad H, Zeiler AG (1973) Chem Rev 73:75–91
27. Wang P, Qin J, Yuan D, Wang Y, Yao Y (2015) ChemCatChem
7:1145–1151
28. Sekine K, Mawatari T, Yamada T (2015) Synlett 26:2447–2450
29. Li DY, Chen HJ, Liu PN (2015) Adv Synth Catal 357:1193–1198
30. Liu AH, Li YN, He LN (2012) Pure Appl Chem 84:581–602
31. Ueno A, Kayaki Y, Ikariya T (2013) Green Chem 15:425–430
32. Zhao Y, Yang Z, Luo S, He L (2013) Catal Today 200:2–8
33. Seayad J, Seayad AM, Ng JKP, Chai CLL (2012) Chem-
CatChem 4:774–777
34. Yang ZZ, Li YN, Wei YY, He LN (2011) Green Chem
13:2351–2353
35. Phung C, Ulrich RM, Ibrahim M, Tighe NTG, Lieberman DL,
Pinhas AR (2011) Green Chem 13:3224–3229
Acknowledgements The authors are grateful for the fnancial sup-
port provided by the National Natural Science Foundation of China
(No. 21477010), Guangdong Provincial Natural Science Fund
(No.2017A030313321) and the Open Research Fund Program of
the State Key Laboratory of Geodesy and Earth’s Dynamics (Grant
No.SKLGED2018-1-3-E).
36. Ca’ ND, Gabriele B, Rufolo G, Veltri L, Zanetta T, Costa M,
(2011) Adv Synth Catal 353:133–146
37. Song QW, Yu B, Li XD, Ma R, Diao ZF, Li RG, Li W, He LN
(2014) Green Chem 16:1633–1638
38. Lin XZ, Yang ZZ, He LN, Yuan ZY (2015) Green Chem
17:795–798
39. Samanta A, Zhao A, Shimizu GKH, Sarkar P, Gupta R (2012)
Ind Eng Chem Res 51:1438–1463
40. Didas SA, Choi S, Chaikittisilp W, Jones CW (2015) Acc Chem
Res 48:2680–2687
References
41. Singh B, Polshettiwar V (2016) J Mater Chem A 4:7005–7019
42. Patil U, Fihri A, Emwas A, Polshettiwar V (2012) Chem Sci
3:2224–2229
1. Huang K, Sun CL, Shi ZJ (2011) Chem Soc Rev 40:2435–2452
2. Pinaka A, Vougioukalakis GC (2015) Coord Chem Rev
288:69–97
43. Maity A, Polshettiwar V (2017) Chemsuschem 10:3866–3913
44. Steele BCH, Heinzel A (2001) Nature 414:345–352
45. Meng G, Ma G, Ma Q, Peng R, Liu X (2007) Solid State Ionics
178:697–703
3. Yu D, Teong SP, Zhang Y (2015) Chem Rev 293–294:279–291
4. Goeppert A, Czaun M, Jones JP (2014) Chem Soc Rev
43:7995–8048
5. Peppel W (1958) J Ind Eng Chem 50:767–770
46. Liu ZG, Ouyang JH, Sun KN (2011) Fuel Cell 11:153–157
1 3

L. Feng et al.
47. Wang C, Wang Y, Zhang A, Cheng Y, Chi F, Yu Z (2013) J
Mater Sci 48:8133–8139
52. Hongsong Zh, Suran L, Shaokang G (2012) JMEPEG
21:1046–1050
48. Bezerra Lopes FW, de Souza CP, Vieira de Morais AM, Dallas
JP, Gavarri JR (2009) Hydrometallurgy 97:167–172
49. Besikiotis V, Knee CS, Ahmed I, Haugsrud R, Norby T (2012)
Solid State Ionics 228:1–7
53. Jiang X, He S, Li S, Baia Y, Shao L (2019) J Mater Chem A
7:16704–16711
54. Jiang X, Li S, He S, Bai Y, Shao L (2018) J Mater Chem A
6:15064–15073
50. Bayal N, Singh R, Polshettiwar V (2017) Chemsuschem
10:2182–2191
55. Dong Z, Le X, Li X, Zhang W, Dong C, Ma J (2014) Appl Catal
B 158–159:129–135
51. Ran F, Yang X, Xu X, Bai Y, Shao L (2019) Electrochim Acta
301:117–125
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