Moein-Najafabadi and Safaei-Ghomi BMC Chemistry
https://doi.org/10.1186/s13065-024-01270-8(2024) 18:155

BMC Chemistry

Open Access

RESEARCH

Silica/APTPOSS anchored on MnFe2O4 as anefficient nanomagnetic composite for the
preparation of spiro-pyrano [2, 3-c] chromenederivatives
Samira Moein-Najafabadi1 and Javad Safaei-Ghomi1*
Abstract
The synthesis of Octakis [3- (3-amino propyl triethoxysilane) propyl] octa-silsesquioxane (APTPOSS), a derivative ofpolyhedral oligomeric silsesquioxane, was utilized to produce an efficient nanocomposite. MNPs@Silica/APTPOSS
was characterized through scanning electron microscopy, Fourier transform infrared spectroscopy, vibrating sample
magnetometry, X-ray diffraction, and Thermogravimetric analysis. These magnetic nanoparticles, a combination oforganic-inorganic hybrid polyhedral oligomeric silsesquioxane, were utilized as a proficient heterogeneous catalyst
in the one-pot synthesis of spirooxindoles derivatives. Furthermore, they could be swiftly isolated and reused six
times while maintaining their catalytic efficiency.
Keywords Nanocomposite, Oligomeric silsesquioxane, Heterogeneous, One-pot synthesis, Spirooxindoles

Introduction
Utilizing heterogeneous catalysts has emerged as a valuable approach for addressing multiple challenges, suchas catalyst retrieval, product isolation, environmental
impact, and elevated reaction temperatures [1, 2]. In
this context, the utilization of nanometals as catalysts
has experienced rapid expansion, leading to the development of numerous active and efficient nanocatalysts with
distinct advantages over traditional catalysts, including
enhanced activity and durability [3–5].
Magnetic nanoparticles (MNPs) are promising support materials for heterogeneous catalysts because of
their straightforward synthesis, large surface area, great*Correspondence:
Javad Safaei-Ghomi
safaei@kashanu.ac.ir
1
Department of Organic Chemistry, Faculty of Chemistry, University of
Kashan, P.O. Box 87317-51167, Kashan, I. R. of Iranthermal and chemical stability, potential for surface
modification, low toxicity, and cost-effectiveness [6–10].
Additionally, employing an external magnet allows foreasy separation of catalyst-loaded MNPs from reaction
products, eliminating filtration and simplifying catalyst
recycling [11].
Octakis [3-(3aminopropyltriethoxysilane) propyl] octasilsesquioxane, commonly abbreviated as APTPOSS, is asilsesquioxane-based organic-inorganic hybrid material[12]. It consists of a central silicon atom surrounded byeight organic groups, each containing an amino groupand three ethoxy groups. APTPOSS is a versatile material with a wide range of potential applications due to its
unique properties. APTPOSS is often employed as a surface modifier or coating agent due to its ability to form
strong bonds with organic and inorganic substrates [13].
The organic groups on its surface provide functionalgroups that can easily react with other molecules, allowing for tailored surface modifications. This property© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0
International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you
give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified thelicensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images orother third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to thematerial. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation
or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://
creativecommons.org/licenses/by-nc-nd/4.0/.

Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

makes APTPOSS useful in adhesion promotion, surfacefunctionalization, and the development of hybrid materials [14, 15].
In addition to its surface modification capabilities,
APTPOSS also exhibits excellent thermal stability andmechanical strength. The inorganic silica core provides
a rigid framework that enhances the material’s durability
and resistance to high temperatures. This makes APTPOSS suitable for applications in harsh environments or
where high-temperature stability is required [16].
Furthermore, APTPOSS possesses interesting opticalproperties, including high transparency in the visible andnear-infrared regions of the electromagnetic spectrum.
This characteristic makes it a promising material for optical applications such as lenses, coatings, and optoelectronic devices [17]. Overall, Octakis [3-(3 aminopropyl
triethoxysilane) propyl] octasilsesquioxane (APTPOSS)
is a versatile hybrid material with a wide range of potential applications. Its unique combination of organic andinorganic components, excellent surface modification
capabilities, thermal stability, mechanical strength, andoptical properties, make it a valuable material for various
industries and research fields [18, 19].
The indole scaffold is a bicyclic heterocyclic organic
compound. It is a structural component of the aminoacid tryptophan found in many natural products andpharmaceuticals [20, 21]. Indoles exhibit diverse biological activities, including anti-inflammatory, anti-cancer,
and anti-depressant properties [22]. The indole scaffold isalso found in many synthetic compounds, such as the dye
indigo and the drug LSD [23]. Indoles are an importantclass of compounds with a wide range of applications in
the pharmaceutical, agricultural, and materials science
industries (Fig. 1) [24–26].
Utilizing the one-pot multicomponent reaction protocol is a highly effective approach for achieving optimal
synthesis due to its advantages in time and energy efficiency, high atom efficiency, and ease of execution [27].
Nitrogen-containing heterocyclic compounds are important in organic synthesis and medicinal chemistry [28,29]. Among these, spirooxindole derivatives are valuable

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fused heterocycles that are essential building blocks forsynthetic compounds, natural products, and pharmaceutical molecules [30, 31]. While various practical methods have been explored to prepare spiro 4 H-pyrans,each method comes with its own set of advantages andlimitations that restrict their applicability [32, 33]. Therefore, developing a new efficient strategy for producing
these fused heterocyclic structures is imperative. Building upon our previous research endeavors [34–36],
we present a straightforward approach for fabricating
MnFe2O4@SiO2/APTPOSS as a powerful catalyst for the
one-pot reaction involving activated methylene compounds, 1,3 dicarbonyl compounds, and isatins under
mild conditions (Fig. 2).

Results and discussion
Structural analysis of the MnFe2O4@SiO2/APTPOSS as thecatalyst

Figure 3 demonstrates the sequential process for immobilizing MnFe2O4 with a Polyhedral Oligomeric Silsesquioxanes-based inorganic-organic hybrid. The MNPs
(MnFe2O4) were first synthesized using a co-precipitation method in a basic solution. It is known that thesurface of the MNPs can be functionalized using various
surface modifiers. Subsequently, octakis (3 chloropropyl)
octasilsesquioxane was synthesized through hydrolyzing
3-chloropropyltrimethoxysilane in an acidic environment. React ClPOSS with 3-aminopropyltriethoxysilane
to produce APTPOSS. The final step involved treating
MnFe2O4 with an aminopropyltriethoxysilane derivative
and TEOS. The MnFe2O4@SiO2/APTPOSS was distinguished using TEM, SEM, VSM, Fourier transform infrared (FT-IR) analysis, TGA, and X-ray diffraction (XRD)
techniques.
Figure 4 illustrates the X-ray diffraction patterns of thesynthesized APTPOSS, MnFe2O4, and MnFe2O4@SiO2/
APTPOSS. The XRD patterns of the MnFe2O4 nanoparticles with and without POSS show consistent peaks, indicating that the crystalline spinel structure of MnFe2O4
is preserved during the APTPOSS coating process. Specifically, the X-ray diffraction (XRD) patterns reveal six

Fig. 1 Indole scaffold in physiologically and pharmacologically relevant substancesMoein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

Fig. 2 Synthesis of spirooxindole using MNPs@SiO2/APTPOSS

Fig. 3 Preparation routes to MnFe2O4@SiO2/APTPOSS nanoparticles

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Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

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Fig. 4 The X-ray diffraction patterns of (a) APTPOSS, (b) MnFe2O4 and (c) MnFe2O4@SiO2/APTPOSS

Fig. 5 Fourier transform-infrared (FT‐IR) spectra of (a) ClPOSS, (b) MnFe2O4, (c) APTPOSS and (d) MnFe2O4@SiO2/APTPOSS

characteristic peaks corresponding to a cubic phaseof manganese iron oxide at 2θ values of 30.18°, 35.97°,
43.22°, 53.92°, 57.42°, and 63.03° for both MnFe2O4 and
MnFe2O4@SiO2/APTPOSS in Fig. 4(b) and (c). Additionally, the broad peaks observed in Fig. 4(a) and (c) at 2θ
values ranging from 16° to 28° are attributed to an amorphous Si-O bond.
The Fourier transform infrared spectra in Fig. 5 illustrate the characteristic features of ClPOSS, MnFe2O4,
APTPOSS, and MnFe2O4@SiO2/APTPOSS. Notablefeatures of the ClPOSS molecules include peaks at
2955 cm− 1 (C-H bond stretching), 1102 cm− 1 (Si-O-Si
band stretching), and 810 cm− 1 (C-Cl bond stretching).
Figure 5(b) and (d) show common features, including
peaks at 489, 576, 3437, and 1627 cm− 1, which depict thestretching vibrations of Mn-O bonds, Fe-O bonds, O-H
bonds, and O-H bond bending. The successful incorporation of Silica/ POSS-based inorganic-organic hybrid
on the surface of MnFe2O4 is indicated by broad peaks
around 1000–1160 cm− 1 associated with Si-O bondstretching vibrations. Additionally, C-H bond stretchingat 2915–2965 cm− 1 and C-H bond bending vibration at
approximately 1470 cm− 1 is observed in Fig. 5(c) and (d).
Figure 6 illustrates the TGA analysis of MnFe2O4@
SiO2/APTPOSS. It demonstrates a decline in weight ofapproximately 28% between 200 and 500 °C, which can
associated with the degradation of the organic components. Consequently, the catalyst exhibits stability up toless than 200 °C, affirming its suitability for application inorganic reactions at temperatures around 80 °C.
The FE-SEM images in Fig. 7 compare the magnetic
nanoparticles. As depicted in Fig. 7(a), the uncoated
MnFe2O4 seeds have a size of about 38 nm and display
acceptable uniformity. The SEM image in Fig. 7(b) indicates the MnFe2O4 coated with SiO2/POSS have preserved their morphology, but this does not apply toparticle size and aggregation. The observed accumulation
and alterations in particle size lead to the conclusion thatthe nanocatalyst has been effectively synthesized.
To investigate more accurately the morphology of
MnFe2O4@SiO2/APTPOSS nanocomposites, TEM analysis was applied (Fig. 8). TEM images confirmed that theMoein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

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Fig. 6 Thermal gravimetric analysis of MnFe2O4@SiO2/APTPOSS

Fig. 7 The FE-SEM images of (a) MnFe2O4 and (b) MnFe2O4@SiO2/APTPOSS

Fig. 8 The TEM images of MnFe2O4@SiO2/APTPOSS

magnetic nanocomposites have spherical morphology
with uniform distribution.
The magnetic characteristics of MnFe2O4 and MNPs@
SiO2/APTPOSS were examined using a vibrating sample
magnetometer at room temperature (Fig. 9). The magnetization hysteresis loops for two samples are S-likeand show superparamagnetic properties for them. The
saturation magnetization (Ms) is 32.5 Oe for MnFe2O4
and 21.8 Oe for MNPs@SiO2/APTPOSS. The magnetic
saturation value decreases by approximately 10.7 mug− 1
following the coating process, possibly attributed to theMoein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

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Fig. 9 Comparison of VSM analysis for MnFe2O4 and MNPs@SiO2/APTPOSS

Fig. 10 The impact of various solvents on the preparation of oxindole using MnFe2O4@SiO2/APTPOSS

enhanced surface area facilitating successful nanoparticle
coating with SiO2 and APTPOSS.
Different solvents were used to examine the reactivity
of isatin derivatives, 1, 3-dicarbonyl compounds (2a-d),
and malononitrile 1. A good yield was achieved when
the reaction was conducted in ethanol (Fig. 10). Subsequently, the reaction was carried out using different catalysts and without a catalyst. It was found that MnFe2O4@
SiO2/APTPOSS was the most effective catalyst, resulting in a 96% yield of product 3a. The impact of catalystloading was then investigated using 5 mg and 15 mg of
MnFe2O4@SiO2/APTPOSS, respectively. The experimental findings indicated that using 10 mg of MnFe2O4@
SiO2/APTPOSS as a catalyst yielded the most favorable
results. Any deviation from this particular catalyst loading, whether reduced or increased, resulted in a drop in
the total product yield.
Various reaction conditions were explored in the experimental model involving isatin, dimedone, and malononitrile to achieve optimal production yield and showcase
the effectiveness of the catalyst. The results indicated that

conducting the reaction at 80 ̊C with 10 mg of the catalyst(MnFe2O4@SiO2/APTPOSS) in ethanol as the solvent
leads to an enhanced production yield (Table 1, entry 5).
Table 2 displays the results obtained from the synthesis of various spiro[indoline-3,4’-pyrano[3,2-c]chromene],spiro[indoline-3,5’-pyrano[2,3-d]pyrimidine], and spiro[chromene-4,3’-indolines] compounds.
The reactions took place in ethanol as a solvent at a temperature of 80 ̊C, using isatin derivatives and different 1,
3-dicarbonyls.
The catalyst’s reusability is a well-established propertyof significant importance. Our study focused on utilizing
MNPs@SiO2/APTPOSS as a catalyst in optimized conditions. Following the reaction, the catalyst was washedwith acetone and methanol and dried in an oven at 65 °C
for 70 min. It was then directly used with new substrates
under the same conditions. The results demonstrate thatthe catalyst was effectively employed in six consecutive
reaction cycles without a noticeable decrease in productyield, showing initial yields of 97% and 90% by the sixth
cycle (Fig. 11).

Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

Table 1 Reported catalytic system for the formation of
spirooxindole derivativesa
Entry Catalyst

1

-

2

MnFe2O4@SiO2(20 mg)MnFe2O4@SiO2/APTPOSS(10 mg)MnFe2O4@SiO2/APTPOSS(10 mg)MnFe2O4@SiO2/APTPOSS (10 mg)
MnFe2O4@SiO2/APTPOSS(10 mg)MnFe2O4@SiO2/APTPOSS(10 mg)Amino-appended bcyclodextrin (5 mol%)
THAM (30 mol%)TiO2-CNTs (24 mg)

3
4
5
6
7
8
9
10

Solvent/
Temp.
(◦C)
EtOH / 80

Time Yieldb Ref.
(min) (%)
90

30

EtOH / 80

40

60

EtOH / 50

20

75

Solvent15
free / 80
EtOH / 80 10

80

EtOH / 90

reflux94

H2O / 80

30

70

H2O / RT

7h

91

This
work
This
work
This
work
This
work
This
work
This
work
This
work
[37]

EtOH / RT
H2O / RT

4h
6h

94
94

[38]
[39]

97

Bold entry is the best one of the experimenta

Reaction conditions: isatin (1mmol), malononitrile (1 mmol), and 1,3 dicarbonylcompounds (1 mmol) in presence MnFe2O4@SiO2/APTPOSS (10 mg) in EtOH
under reflux conditionsb

Isolated yields

A plausible mechanism for the preparation of spiro
oxindole

A potential mechanism is suggested for the one-step
synthesis of 2-amino-7, 7-dimethyl-2’,5-dioxo-5,6,7,8
tetrahydrospiro[chromene-4,3’-indoline]-3-carbonitrile
via a three-component reaction. At first, an acidic catalytic method was employed to carry out the Knoevenagel
condensation and form intermediate (A) Then, intermediate A underwent a Michael addition with dimedone to
produce intermediate (B) Finally, the target product (3a)was generated through intramolecular cyclization. At theend of the reaction, the catalyst could be recovered byexternal permanent magnet (Fig. 12).

Conclusions
We were able to effectively synthesize composite
nanoparticles in our research by blending manganeseiron oxide MNPs (MnFe2O4) with APTPOSS, resulting in
the production of oxindoles. The reaction was efficiently
carried out quickly and with minimal catalyst usage.
Moreover, the resulting catalyst exhibited numerous benefits, including long-term stability, exceptional catalytic
activity for this specific reaction, effortless separationof the catalyst through an external magnetic field, andstraightforward work-up procedures. Additionally, thecatalyst can be conveniently retrieved and reused multiple times without experiencing a noticeable decline in its
catalytic effectiveness. The present method is expected toPage 7 of 11

apply to generating diverse libraries because of the plentiful availability of isatins and 1, 3-dicarbonyl compounds.
Overall, the widespread adoption of this technique incombinatorial chemistry and drug discovery holds great
promise for advancing the development of new pharmaceutical agents and improving treatment options for various medical conditions.

Experimental section
GeneralAll chemicals and solvents utilized in the investigation
were procured commercially and were not subjected tofurther purification. Fourier transform infrared (FT IR)
spectroscopy was analyzed using a Nicolet Magna-400
spectrometer with KBr pellets. 1H NMR data were gathered in DMSO-d6 using a Bruker DRX 400 spectrometerwith tetramethylsilane as the internal reference. Powder
X-ray diffraction (XRD) was performed using a Philips X’pert diffractometer with monochromatized Cu Kα
radiation (λ = 1.5406 Å). Additionally, the magnetic properties of magnetite nanoparticles were measured utilizing
a vibrating sample magnetometer (PPMS-9 T) at 300 K at
Iran’s Kashan University. The nanoparticles’ morphology
was investigated using field emission scanning electron
microscopy (FE-SEM) with model MIRA3. The microscopic morphology of the nanoparticles was observed
using a Philips transmission electron microscope (TEM)
operating at 100 Kv. Thermogravimetric analysis (TGA)
curves were recorded with a V5.1 A DuPont 2000.
General procedure for the synthesis of MnFe2O4
nanoparticles

Following a 30-minute exposure to nitrogen gas
in 200 mL of purified, deoxygenated water, 5 g ofMn(NO3)2.4H2O and 14 g of Fe(NO3)3.6H2O were dissolved in ultrapure water with vigorous mechanical stirring. Subsequently, the mixture was agitated while 2.0 M
NaOH solution was incrementally added until reachinga pH of 11. The mixture was then heated to 100 °C andmaintained at this temperature for 2 h. Under the influence of an external magnetic field, a black precipitate wascollected and subsequently rinsed with ultrapure water
three times to eliminate contaminants such as OH−,
NO3−, and Na+. Following freeze-drying, pure MnFe2O4
nanoparticles were ultimately obtained.
Preparation of ClPOSS nanoparticles

The initial substance octakis (3 chloropropyl) octasilsesquioxane was synthesized following the procedure
outlined by Dittmar et al. [40]. A mixture of 3 Chloropropyltrimethoxysilane (20 g), 450 ml of methanol, and22.5 ml of concentrated hydrochloric acid was stirred fora minimum of 4 weeks at room temperature. After thisperiod, colorless crystals (3.6 g) were obtained, whichReaction conditions: isatin (1mmol), malononitrile (1 mmol), and 1,3 dicarbonyl compounds (1 mmol) in presence MnFe2O4@SiO2/APTPOSS (10 mg) in EtOH under reflux conditionsb Isolated
yieldsa

Table 2 Preparation of spirooxindole derivatives using MnFe2O4@SiO2/APTPOSS catalysta

Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155
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Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

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Fig. 11 Recycling of MnFe2O4@ SiO2/APTPOSS as the catalyst

Fig. 12 The probable mechanism for the preparation of spirooxindole using MnFe2O4@SiO2/APTPOSS

were subsequently washed with water and dried undervacuum at 60 °C for 24 h.
Preparation of octakis [3-(3 aminopropyltriethoxysilane)
propyl] octasilsesquioxane (APTPOSS)

Under a nitrogen atmosphere, 2.07 g of ClPOSS (twommol) and 4.43 g of 3-Aminopropyltriethoxysilane (20mmol) were combined in a reaction vessel. The solution
was stirred at 100 °C for two days, as illustrated in Fig. 3.
Subsequently, the combination was allowed to cool toambient temperature, followed by filtration of the solution and subsequent washing with methanol and acetone.
The resulting product, APTPOSS, was obtained as a pale
brown solid after drying under a vacuum and was stored
for future use.

Preparation of MnFe2O4@SiO2/APTPOSS MNPs

At first, 1.0 g of the magnetic manganese iron oxidethat was produced was dispersed in a solution containing 1.6 ml of ammonium hydroxide, 10 ml of deionizedwater, and 30 ml of absolute ethanol using ultrasonicvibration for 20 min to create an active site for binding to
MnFe2O4. Subsequently, 0.45 g of APTPOSS previously
sonicated in deionized water, was added to this suspension. Following this, a mixture containing 0.9 ml of tetraethylorthosilicate diluted in ethanol (9 ml) was added
dropwise to the suspension while continuously stirring at
80 °C. The reaction was allowed to progress for two days
until it was completed, as shown in Fig. 3. The MnFe2O4@
SiO2/APTPOSS product was then retrieved using a magnet after the mixture had cooled down. Afterward, theproduct was subjected to multiple washes with acetone
and ethanol and dried in a vacuum at 70 °C.

Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

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Fig. 13 An attractive outline of the reaction

A common procedure for the synthesis of (3a-n)

In a 50-ml round-bottom flask, one mmol each of Isatinderivatives, barbituric acid, dimedone or 4-hydroxycoumarin, and malononitrile were mixed with 10 mgof the catalyst (MNPs@SiO2/APTPOSS). The mixture
was heated at 80 °C in the presence of ethanol until thereaction was complete. The progress of the reaction wasmonitored using thin-layer chromatography. The resulting products were purified by drying and washing withethanol to obtain pure compounds (Fig. 13).
Abbreviations
MNPs	Magnetic nanoparticles.
APTPOSS	[3- (3-amino propyl triethoxysilane) propyl] octa-silsesquioxane.
TEM	Transmission electron microscopy.
SEM	Scanning Electron Microscopy.
VSM	Vibrating Sample Magnetometer.
FT-IR	Fourier transform infrared.
XRD	X-Ray diffraction.
CIPOSS	(3 chloropropyl) octasilsesquioxane.
TEOS	Tetraethyl Orthosilicate.
Ms	Saturation magnetization.
DMSO	Dimethyl sulfoxide.

Supplementary Information

The online version contains supplementary material available at https://doi.
org/10.1186/s13065-024-01270-8.
Supplementary Material 1
Acknowledgements
The authors wish to thank the University of Kashan for providing facilities forthis work.
Author contributions
Samira Moein Najafabadi: Investigation, Writing-Original draft preparation,
Visualization.Javad Safaei Ghomi: Supervision, Conceptualization, Reviewing
and Editing.
Funding
Not applicable.
Data availability
The data about this study is fully accessible in the published article and its
supplementary information file.

Declarations
Ethics approval and consent to participate
Not applicable.
Consent for publication
Not Applicable.
Competing interests
The authors declare no competing interests.
Received: 23 April 2024 / Accepted: 15 August 2024

References
1. Sadeghzadeh SM, Zhiani R, Emrani S. Pd/APTPOSS@ KCC-1 as a new andefficient support catalyst for C–H activation. RSC adv. 2017;7:24885–94.
2. Miceli M, Frontera P, Macario A, Malara A. Recovery/reuse of heterogeneous
supported spent catalysts. Catalysts. 2021;11:591.
3. Isfahani AL, Mohammadpoor-Baltork I, Mirkhani V, Khosropour AR, Moghadam M, Tangestaninejad S, Kia R. Palladium nanoparticles immobilized on
nano‐silica triazine dendritic polymer (Pdnp‐nSTDP): an efficient and reusable
catalyst for Suzuki–Miyaura cross‐coupling and heck reactions. Adv Synth
Catal. 2013;355:957–72.
4. Chadha U, Selvaraj SK, Ashokan H, Hariharan SP, Mathew Paul V, Venkatarangan V, Paramasivam V. Complex nanomaterials in catalysis for chemicallysignificant applications: from synthesis and hydrocarbon processing to
renewable energy applications. Adv Mater Sci Eng. 2022;2022:1–72.
5. Narayan N, Meiyazhagan A, Vajtai R. Metal nanoparticles as green catalysts.
Mater. 2019;12:3602.
6. Dong Y, Xue F, Wei Y. Magnetic nanoparticles supported N-heterocyclic palladium complex: synthesis and catalytic evaluations in Suzuki cross-coupling
reaction. J Phys Chem Solids. 2021;153:110007.
7. Vargas-Ortiz JR, Gonzalez C, Esquivel K. Magnetic iron nanoparticles:
synthesis, surface enhancements, and biological challenges. Processes.
2022;10:2282.
8. Das SK, Chatterjee S, Bhunia S, Mondal A, Mitra P, Kumari V, Pradhan A,
Bhaumik A. A new strongly paramagnetic cerium-containing microporous MOF for CO2 fixation under ambient conditions. Dalton Trans.
2017;46:13783–92.
9. Basu S, Kayal U, Maity S, Ghosh P, Bhaumik A, Mukhopadhyay C. Utility of
the Ditopic Nature of magnetically recyclable NiFe2O4 Nano-Catalyst for theGreen synthesis of two different Spiro [indoline‐pyrrolizine] scaffolds. ChemistrySelect. 2018;3:12755–63.
10. Mondal J, Sen T, Bhaumik A. Fe3O4@ mesoporous SBA-15: a robust and magnetically recoverable catalyst for one-pot synthesis of 3, 4-dihydropyrimidin-2(1 H)-ones via the Biginelli reaction. Dalton Trans. 2012;41:6173–81.
11. Abu-Dief AM, Abdel-Fatah SM. Development and functionalization of magnetic nanoparticles as powerful and green catalysts for organic synthesis.
Beni-Suef University. J Basic Appl Sci. 2018;7:55–67.

Moein-Najafabadi and Safaei-Ghomi BMC Chemistry(2024) 18:155

12. Rathnayake H, White J, Dawood S. Polysilsesquioxane-based organicinorganic hybrid nanomaterials and their applications towards organic
photovoltaics. Synth Met. 2021;273:116705.
13. Chen Y, Feng L, Sadeghzadeh SM. Reduction of 4-nitrophenol and 2-nitroaniline using immobilized CoMn2O4 NPs on lignin supported on FPS. RSC adv.
2020;10:19553–61.
14. Waki M, Mizoshita N, Tani T, Inagaki S. Periodic mesoporous organosilica
derivatives bearing a high density of metal complexes on pore surfaces.
Angew Chem. 2011;49:11871–5.
15. Kowalewska A. (2018) Self-assembly of POSS-containing materials. Polymer/
POSS nanocomposites and hybrid materials: preparation, properties, applications, pp. 45–128.
16. Drobota M, Ursache S, Aflori M. Surface functionalities of polymers for biomaterial applications. Polym. 2022;14:2307.
17. Kim YB, Cho JW, Lee YJ, Bae D, Kim SK. High-index-contrast photonic
structures: a versatile platform for photon manipulation. Light: Sci& Appl.
2022;11:316.
18. Sypabekova M, Hagemann A, Rho D, Kim S. 3-Aminopropyltriethoxysilane(APTES) deposition methods on oxide surfaces in solution and vapor phases
for biosensing applications. Biosens. 2022;13:36.
19. Safaei-Ghomi J, Nazemzadeh SH, Shahbazi‐Alavi H. Preparation and characterization of Fe3O4@ SiO2/APTPOSS core–shell composite nanomagnetics
as a novel family of reusable catalysts and their application in the one‐pot
synthesis of 1, 3‐thiazolidin‐4‐one derivatives. Appl Organomet Chem.
2016;30:911–6.
20. Chadha N, Silakari O. Indoles as therapeutics of interest in medicinal chemistry: Bird’s eye view. Eur J Med Chem. 2017;134:159–84.
21. Heravi MM, Amiri Z, Kafshdarzadeh K, Zadsirjan V. Synthesis of indole
derivatives as prevalent moieties present in selected alkaloids. RSC adv.
2021;11:33540–612.
22. Sachdeva H, Mathur J, Guleria A. Indole derivatives as potential anticancer
agents: a review. J Chil Chem Soc. 2020;65:4900–7.
23. Sravanthi TV, Manju SL. Indoles—A promising scaffold for drug development.
Eur J Pharm Sci. 2016;91:1–0.
24. Gaikwad DD, Chapolikar AD, Devkate CG, Warad KD, Tayade AP, Pawar RP,
Domb AJ. Synthesis of indazole motifs and their medicinal importance: an
overview. Eur J Med Chem. 2015;90:707–31.
25. Ferrer L, Mindt M, Wendisch VF, Cankar K. (2023) Indoles and the advances intheir biotechnological production for industrial applications. Syst Microbiol
Biomanuf 1–17.
26. Almandil NB, Taha M, Gollapalli M, Rahim F, Ibrahim M, Mosaddik A, Anouar
EH. Indole bearing thiadiazole analogs: synthesis, β-glucuronidase inhibition
and molecular docking study. BMC Chem. 2019;13:1–0.
27. Moein Najafabadi S, Safaei Ghomi J. Synthesis of COF-SO3H immobilizedon manganese ferrite nanoparticles as an efficient nanocomposite in the
preparation of spirooxindoles. Sci Rep. 2023;13:22731.
28. Heravi MM, Zadsirjan V. Prescribed drugs containing nitrogen heterocycles:
an overview. RSC Adv. 2020;10:44247–311.

Page 11 of 11

29. Oboudatian HS, Safaei-Ghomi J. Silica nanospheres KCC-1 as a good catalyst
for the preparation of 2-amino-4H-chromenes by ultrasonic irradiation. Sci
Rep. 2022;12:2381.
30. Nasri S, Bayat M, Farahani HV, Karami S. (2020) Synthesis of new functionalized thiazolo pyridine-fused and thiazolo pyridopyrimidine-fused spirooxindoles via one-pot reactions. Heliyon 6.
31. Panda SS, Girgis AS, Aziz MN, Bekheit MS. Spirooxindole: a versatile biologically active heterocyclic scaffold. Molecules. 2023;28:618.
32. Li MM, Duan CS, Yu YQ, Xu DZ. A general and efficient one-pot synthesis ofspiro [2-amino-4H-pyrans] via tandem multi-component reactions catalyzed
by Dabco-based ionic liquids. Dyes Pigm. 2018;150:202–6.
33. Zhiani R, Sadeghzadeh SM, Emrani S. Synthesis of spiroindenopyridazine-4
H-pyran derivatives using Cr-based catalyst complexes supported on KCC-1
in aqueous solution. RSC Adv. 2018;8:6259–66.
34. Ghasemzadeh MA, Mirhosseini-Eshkevari B, Abdollahi-Basir MH. Greensynthesis of spiro [indoline-3, 4′-pyrano [2, 3-c] pyrazoles] using Fe3O4@l-arginine as a robust and reusable catalyst. BMC Chem. 2019;13:119.
35. Ziarani GM, Moradi R, Lashgari N. Asymmetric synthesis of chiral oxindoles
using isatin as starting material. Tetrahedron. 2018;74:1323–53.
36. Zhao H, Zhao Y. Engaging isatins and amino acids in multicomponent onepot 1, 3-dipolar cycloaddition reactions—easy access to structural diversity.
Molecules. 2023;28:6488.
37. Ren Y, Yang B, Liao X. The amino side chains do matter: chemoselectivity
in the one-pot three-component synthesis of 2-amino-4 H-chromenes by
supramolecular catalysis with amino-appended β-cyclodextrins (ACDs) inwater. Catal Sci Technol. 2016;6:4283–93.
38. Toorbaf M, Moradi L. Preparation of GO/SiO2/PEA as a new solid basecatalyst for the green synthesis of some spirooxindole derivatives. RSC Adv.
2021;11:21840–50.
39. Abdolmohammadi S, Rasouli Nasrabadi SR, Dabiri MR, Banihashemi Jozdani
SM. TiO2 nanoparticles immobilized on Carbon nanotubes: an efficientheterogeneous Catalyst in Cyclocondensation reaction of Isatins with Malononitrile and 4-Hydroxycoumarin or 3, 4‐Methylenedioxyphenol under mild
reaction conditions. Appl Organomet Chem. 2020;34:5462.
40. Dittmar U, Hendan BJ, Flörke U, Marsmann HC. Funktionalisierte octa(propylsilsesquioxane)(3-XC3H6) 8 (Si8O12) modellverbindungen für oberflächenmodifizierte kieselgele. J Organomet Chem. 1995;489:185–94.

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