Fe3O4@SiO2-PMA-Cu magnetic nanoparticles as a novel catalyst for green synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles | Scientific Reports

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Carousel with three slides shown at a time. Use the Previous and Next buttons to navigate three slides at a time, or the slide dot buttons at the end to jump three slides at a time. Ferric Oxide Yellow

Fe3O4@SiO2-PMA-Cu magnetic nanoparticles as a novel catalyst for green synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles | Scientific Reports

Elham Arefi, Amir Khojastehnezhad & Ali Shiri

H. Rajabi-Moghaddam, MR Naimi-Jamal & M. Tajbakhsh

Firouz Matloubi Moghaddam, Atefeh Jarahiyan, … Ali Pourjavadi

Reza Taheri-Ledari, Fateme Sadat Qazi, ... Ali Maleki

Reza Taheri-Ledari, Fereshteh Rasouli Asl, … Ali Maleki

Sara Sobhani, Hamed Zarei & José Miguel Sansano

Hassan Sepehrmansourie, Mahmoud Zarei, … Sadegh Rostamnia

Fereshte Hassanzadeh-Afruzi, Somayeh Asgharnasl, … Ali Maleki

Ali Maleki & Razieh Firouzi-Haji

Scientific Reports volume  12, Article number: 11939 (2022 ) Cite this article

The magnetic nanoparticles of Fe3O4 were synthesized through a solid-state reaction of hydrated iron (III) chloride, hydrated iron (II) chloride and NaOH, and then purified by calcination at high temperature. In order to protect ferrite nanoparticles from oxidation and agglomeration, and to manufacture a novel catalytic system of anchored copper on the magnetic substrate, the Fe3O4 was core-shelled by adding tetraethyl orthosilicate. Next, the prepared Fe3O4@SiO2 was supported by phosphomolybdic acid (PMA) as the second layer of nanocomposite at 80 °C in 30 h. Eventually, the new nanocomposite of Fe3O4@SiO2-PMA-Cu was successfully synthesized by adding copper (II) chloride solution and solid potassium borohydride. The structure of magnetic nanocatalyst was acknowledged through different techniques such as EDS, VSM, XRD, TEM, FT-IR, XPS, TGA, BET and FESEM. The synthesis of β-thiolo/benzyl-1,2,3-triazoles from various thiiranes, terminal alkynes and sodium azide was catalyzed by Fe3O4@SiO2-PMA-Cu nanocomposite in aqueous medium. In order to obtain the optimum condition, the effects of reaction time, temperature, catalyst amount and solvent were gauged. The recycled catalyst was used for several consecutive runs without any loss of activity.

Multicomponent reactions (MCRs) are potent synthetic procedures for convenient formation of complex organic molecules with structural variety and molecular complexity in one-pot and in one-step method, in which all reactants, reagents and catalysts are added simultaneously under the same reaction conditions. From view point of green chemistry, these reactions are of particular importance due to the significant reduction in the amount of solvents and energy required to separate and purify the intermediates. Moreover, MCRs play considerable roles in various research fields such as synthetic organic, biomedical, industrial chemistry, pharmaceutical and drug discovery research1,2,3,4.

The Huisgen 1,3-dipolar cycloaddition of azides and terminal alkynes has been identified as click chemistry. Click reactions which offer high yield products in a short reaction time under mild conditions are fast, simple to use, easy to purify, eco-friendly, and regiospecific. The Huisgen 1,3-dipolar cycloaddition has found utilizations in a vast diversity of research areas, including pharmaceutical sciences, organic synthesis, and polymer chemistry5.

1,2,3-Triazoles are a very valuable class of heterocycles that have received special attention in recent decades because of their biological and pharmacological activities such as antimicrobial6,7, antibacterial8, antitubercular9, analgesic10, local anaesthetic11, anticancer12, anti HIV13, antifungal14, antiallergic15, anticonvulsant16, antiproliferative17, antiviral, antioxidants18, antimalarial19 and anti-inflammatory20.

In recent years, one-pot click synthesis of β-hydroxy-1,2,3-triazoles from azides, epoxides and terminal alkynes has been reported in the presence of different copper catalysts21,22,23,24,25,26,27,28,29,30. The strained three-membered heterocycles such as epoxides, thiiranes and aziridines are easily ring opened by various nucleophiles such as azides and amines. However, the synthesis of 1,2,3- triazoles from epoxies has been studied in a limited way using azides and alkynes, and the three-membered thiiranes have not been used except in one case recently reported31.

Recently, ferrite nanoparticles due to recovery and reusability have received great attention in biomedicine32,33,34 and modern catalysis research35. The ferrite-based nanoparticles have been widely used as catalysts to perform various multicomponent reactions36,37 and organic syntheses38,39,40,41,42. Compared to the general separation, magnetic separation has appeared as a powerful, efficient, easy and rapid separation method43,44,45,46,47.

Although nano-ferrites are promising class of the catalysts, but their surfaces are hydrophobic with very potent magnetic attractions and high surface to volume ratio, and they always suffer from adsorption troubles due to their high potential of self-aggregation. On the other hand, they are involved in other problems such as low quantity of functional groups on the surface, which disrupts their performance48,49. In order to stabilize them against oxidation, corrosion and aggregation, their surface is modified with organic or inorganic materials. The surface of nano-ferrites could be improved by means of different materials such as polymers, bio molecules, silica, metals, metal oxides, surfactant, etc.50.

Polyoxometalates (POM) are composed of transition metal oxide anions of molybdenum, tungsten and vanadium. This category of compounds bond small species of metal oxides and bulk solid oxometalates. Their exclusive attributes such as vast physical and chemical adaptability, optical and acidic activities as well as reducing and oxidizing capabilities turn them into the excellent compounds for research on the metal oxide activities51. Phosphomolybdic acid (PMA) is one of the well-known polyoxometalates, which is commercially available and affordable52. But, the use of PMA is restricted because of its disadvantages including small surface area, low stability, dissolution effects53 and destruction in aqueous media54. Moreover, it has a high miscibility in polar solvents, which limits its application so it is very difficult to separate and recover55.

In order to prevail these obstacles, PMA is embedded on useful support materials such as silica56, positively charged polymer chains57, metal cations (Cs, Co, Fe etc.)58,59,60, and carbon61. The PMA properties such as high solubility, strong acidity and high negative charge, facilitates its anchoring on any support in various solvents59.

Considering all these aspects, and following our previous studies62,63,64,65,66,67,68, herein we wish to introduce Fe3O4@SiO2-PMA-Cu nanocomposite as an efficient and novel catalyst, whose PMA clusters are found to be anchored on Fe3O4@SiO2 surface, and copper nanoparticles are supported on the PMA surface. The new synthesized nanocomposite was utilized in three-component synthesis of β-thiol-1,4-disubstituted-1,2,3 triazoles from sodium azide, thiiranes, and terminal alkynes as a green and recyclable magnetic catalyst (Fig. 1).

Preparation of β-thiol-1,2,3-triazoles from various thiiranes in the presence of Fe3O4@SiO2-PMA-Cu nanocatalyst.

Immobilization of catalysts on the surface of Fe3O4 nanoparticles, compared with nonmagnetic supports, both increases the dispersion of effective sites of catalyst, and provides the sufficient magnetic properties for easy separation of catalyst from the reaction mixture and thus improves the activity of the surface modified catalyst. In order to protect the catalyst surface against oxidants and corrosive agents and also to prevent aggregation of its particles, the surface of Fe3O4 was coated with silica layer. In addition, through its shell thickness, the silica layer stabilizes the catalyst, controls its particle size and interparticle interactions, and improves its surface effects.

Supporting polyoxometalates onto solid materials and decorating them with suitable porous supports such as metal oxides and MNPs is one of the most effective methods to improve their performance, which is achieved by increasing their active centers and reusability of these heterogeneous materials69. The heterogenization of phosphomolybdic acid on silica coated nanomagnetic materials enabled us to overcome the limitations involved in the separation and recycling of homogeneous PMA. Besides, heteropolyacids such as PMA (H3PMo12O40) have unique structures with a wide range of coordination positions comprising oxygen atoms, which are appropriate for anchoring the single atoms such as copper particles70. Since there are several possible coordination sites on the surface of PMA, it was selected as a support to trap the single metal atoms of copper in this study. The use of atomic catalysts leads to saving the quantity and cost of precious metals since they increase the efficiency and activity of the catalyst dramatically.

The nanoparticles of Fe3O4@SiO2-PMA-Cu were synthesized in a four-step procedure (Fig. 2). First, Fe3O4 was prepared using solid-state reaction of FeCl2·4H2O, FeCl3·6H2O, NaOH, and NaCl in an agate mortar. The crude powder was calcined at 700 °C, and then Fe3O4 particles were acquired with high purity. Coating silica layer on the surface of Fe3O4 nanoparticles was achieved by sonication of a Fe3O4 suspension in an alkaline NH3·H2O solution of tetraethyl orthosilicate (TEOS). Then, PMA was added to a suspension of Fe3O4@SiO2 in ethanol, while being dispersed by sonication. In order to synthesize Fe3O4@SiO2-PMA-Cu, the prepared particles of Fe3O4@SiO2-PMA were added to a solution of CuCl2⋅ 2H2O in water and then the KBH4 powder was gradually added, while the mixture was strongly being stirred. Eventually, the dark brick-red sediment of Fe3O4@SiO2-PMA-Cu was separated magnetically, and then washed with distilled water, and dried at room temperature under air atmosphere.

Four-step synthesis of Fe3O4@SiO2-PMA-Cu.

The different techniques such as FT-IR, X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG), Brunauer–Emmett–Teller (BET) and inductively coupled plasma optical emission spectrometry (ICP-OES) analyses were applied for characterization of new synthesized Fe3O4@SiO2-PMA-Cu nanocatalyst.

To confirm magnetic property of the synthesized nanocatalyst, VSM analysis was carried out. Figure 3 shows the magnetization curves of Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2-PMA and Fe3O4@SiO2-PMA-Cu. As it is revealed in Fig. 3, the saturation magnetization (Ms) of the magnetic catalyst was 6.95 emug−1 and hysteresis phenomenon was not found. The magnetization curve quickly rises without showing any remanence or coercivity, and the sample displays a typical superparamagnetic behavior of soft magnetic materials at room temperature. The superparamagnetic property of these nanoparticles is a vital feature in their application because it prevents accumulation and aggregation of particles and enables them to re-disperse in the absence of a magnetic field immediately. The saturation magnetization (Ms) amount of the Fe3O4@SiO2-PMA-Cu MNPs was appropriate and the separation of the catalyst nanoparticles was easily carried out by using an external magnet.

Magnetization curves of (a) Fe3O4, (b) Fe3O4@SiO2, (c) Fe3O4@SiO2-PMA and (d) Fe3O4@SiO2-PMA-Cu.

Figure 4 shows the FT-IR spectra of Fe3O4, Fe3O4@SiO2, PMA, Fe3O4@SiO2-PMA and Fe3O4@SiO2-PMA-Cu. The absorption peaks at 3449 and 3358 cm−1 are assigned to the stretching vibration of H2O molecules and indicates the OH groups on the surface of the magnetic nanoparticles and hydroxyl groups in PMA structure respectively. The band around 1627 cm−1 corresponds to the bending mode of H2O molecules. The presence of SiO2 is confirmed by stretching and bending vibrations of Si–O. The absorption bands at 803 and 1097 cm−1 are related to Si–O–Si stretching vibrations, and the band observed at 478 cm−1 belongs to the bending vibration of SiO267. The peak at 950 cm−1 belongs to the Mo–O stretching vibrations, which confirms the existence of phosphomolybdic acid71. The formation of Fe3O4 nanoparticles was confirmed by the absorption band at 561 cm−1 which corresponds to the vibration of metal oxide bonds (Fe–O). A band appearing at 478.49 cm−1 is related to the stretching vibrations of Cu–O.

FT-IR (KBr) spectra of (a) Fe3O4, (b) Fe3O4@SiO2, (c) PMA, (d) Fe3O4@SiO2-PMA and (e) Fe3O4@SiO2-PMA-Cu.

The X-ray diffraction (XRD) patterns of Fe3O4, Fe3O4@SiO2, PMA, Cu and Fe3O4@SiO2-PMA-Cu nanoparticles are shown in Fig. 5. As it can be seen, the particle structure of Fe3O4@SiO2-PMA-Cu is amorphous due to the coating of the ferrite surface with layers of silica, phosphomolybdic acid and copper nanoparticles, and the wide peaks confirm the small size of the particles at the nanoscale. In the XRD pattern of nanocomposite, all the peaks of Fe3O4, SiO2, PMA and Cu nanoparticles are detectable. The lines (220), (311), (400), (422), (511), (440), (620) and (533) related to 2Ө = 32.88, 35.64°, 44.11°, 53.43°, 57.60°, 64.01°, 71.95° and 75.01° respectively, are assigned to the diffraction of Fe3O4 crystals. These peaks are compatible with the standard data (JCPDS: 00–43-0317)72. The significant diffraction peaks are observed in case of PMA at 2Ө = 8.95°, 18.49°, 26.43°, 27.65° and 28.84° corresponding to (011), (202), (141), (311) and (312) crystallographic planes respectively (JCPDS: 00–043-0317)73. The broad peak at 2Ө = 22.90° is related to the amorphous SiO2 shell on the surface of Fe3O467. The copper diffraction peaks were compared with the standard sample (JCPDS 04–0836), and the peaks appearing at 2Ө = 43.71°, 50.70°, and 74.32° corresponding to the (111), (200), and (220) planes respectively, revealed the excellent coordination of the synthesized sample with its standard sample31.

X-ray diffraction patterns of (a) Fe3O4, (b) Fe3O4@SiO2, (c) PMA, (d) Cu and (e) Fe3O4@SiO2-PMA-Cu.

TEM and FESEM techniques were used to determine the morphology and size distribution of the nanocatalysts. TEM images of the Fe3O4@SiO2-PMA-Cu nanocomposite are shown in Fig. 6. TEM images show that black and spherical Fe3O4 nanoparticles were synthesized at the nanoscale and coated with a dark gray silica layer, and the silica layer was entirely coated with phosphomolybdic acid. The PMA layer is visible in light gray. The TEM images also display that very small spherical Cu nanoparticles have been successfully deposited on the PMA layer, and they have completely surrounded the outer surface of the catalyst.

TEM images of Fe3O4@SiO2-PMA-Cu.

Figure 7 shows FESEM images of Fe3O4@SiO2-PMA-Cu that approve the formation of nancomposite. Small amounts of agglomerates were observed in the Fe3O4@SiO2-PMA-Cu surface due to the modification of the catalyst surface with non-magnetic layers and decreased magnetic properties. The information obtained from the FESEM images is consistent with the XRD and TEM data.

FESEM of Fe3O4@SiO2-PMA-Cu.

The chemical composition and percentage of nanocomposite elements were acknowledged using EDS data and elemental mapping patterns (Fig. 8). In this spectrum, Fe, Cu, O, Mo, Si and P signals are detectable. The weight percentage of the elements indicates that the expected nanocomposite has been successfully synthesized. In addition, the percentage of copper nanoparticles in the structure of the composite is remarkable. The exact concentration of Fe, Mo, and Cu was also determined by ICP-OES and the resulting amounts were 31.16, 9.2 and 25.84 wt% respectively. These values are consistent with EDS data.

EDS of Fe3O4@SiO2-PMA-Cu and elemental mapping of Fe, O, Si, P, Mo, Cu.

The elemental composition of catalyst intermediates Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2-PMA was also investigated using EDS technique, and the results were presented in Fig. 9.

EDS of (a) Fe3O4, (b) Fe3O4@SiO2 and (c) Fe3O4@SiO2-PMA.

The chemical composition of the different nanoparticles was also characterized using XPS technique. The XPS survey spectra of Fe3O4@SiO2-PMA-Cu, Fe3O4 and Fe3O4@SiO2 nanoparticles are shown in Fig. 10. The elements of Cu, Fe, O, Mo, P and Si were detected on the surface of Fe3O4@SiO2-PMA-Cu. The photoelectron lines representing Cu 2p, Fe 2p, O 1 s, Mo 3d, P 2p and Si 2p at 920, 725/710, 533, 232, 130 and 106 eV respectively can be observed in the survey spectrum of nanocatalyst74. The peaks of Fe element for Fe3O4@SiO2-PMA-Cu and Fe3O4@SiO2 were weakened, indicating that Fe3O4 core was covered by SiO2 shell. The results agreed well with EDS data.

XPS of (a) Fe3O4@SiO2-PMA-Cu, (b) Fe3O4 and (c) Fe3O4@SiO2.

In order to examine the thermal stability of Fe3O4@SiO2-PMA-Cu, thermal gravimetric analysis (TGA) was carried out in the temperature range of 70–800 °C under nitrogen atmosphere (Fig. 11a). The weight loss at 100–180 °C was attributed to the loss of the adsorbed water species from the catalyst surface, and the other at 450–480 °C, corresponding to the decomposition of the Keggin structure accompanied by the evolution of water in PMA. Thus, TGA profile indicated reasonable stability of the catalyst up to 720 °C and it is safe to carry out the reaction even at high temperatures under heterogeneous conditions.

(a) TGA and (b) Nitrogen adsorption–desorption isotherm of Fe3O4@SiO2-PMA-Cu.

The N2 adsorption–desorption isotherm is as shown in Fig. 11b, the apparent hysteresis loop indicates that the catalyst belongs to mesoporous material. The pore properties of the catalyst such as surface area, pore volume and pore diameter were determined by BET test. The specific surface areas calculated using the BET for the synthesized Fe3O4@SiO2-PMA-Cu catalyst was 68.06 m2 g−1. The pore volume was 0.35 cm3 g−1. The corresponding pore size distributions of the catalyst was determined to be 20.56 nm using the Barrett–Joyner–Halenda (BJH), indicating that Fe3O4@SiO2-PMA-Cu catalyst is mesoporous.

The reaction of styrene episulfide, sodium azide and phenyl acetylene was chosen as model reaction, and the synthesis of 2-phenyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)ethane-1-thiol was optimized under different conditions. The various empirical factors such as temperature, catalyst quantity, solvent, reaction time and the amount of reactants were examined, and the acquired results were provided in Table 1. The desired result in terms of product yield, time and reaction conditions was achieved by means of styrene episulfide (1 mmol), sodium azide (1.2 mmol), phenylacetylene (1 mmol) and Fe3O4@SiO2-PMA-Cu (0.1 g) as catalyst in water at 55 °C (Table 1, entry 4). According to the results of the experiments, the presence of catalyst was essential to accomplish the reaction and no reaction was performed in the absence of Fe3O4@SiO2-PMA-Cu even after 10 h (entry 1). The catalyst amount was optimized using different quantities of Fe3O4@SiO2-PMA-Cu nanocomposite (0.05, 0.08, 0.1 and 0.2 g), and 0.1 g of catalyst gave the eligible outcome. The product yield and reaction time were strongly influenced by the concentration of catalyst, so that the product yield and reaction rate increased dramatically by increasing the amount of catalyst from 0.05 to 0.1 g (entries 2–4). The higher amount of catalyst had no effect on the product yield (entry 5). The turn over number (TON) and turn over frequency (TOF) of the present catalyst were also calculated for the model reaction based on the amount of the active metal used (Cu) and they were found to be 1214 and 346 h−1 respectively.

The effect of various polar and non-polar solvents on reaction was examined. The polar solvents such as H2O, CH3CN, EtOH, MeOH, EtOAc and DMF were efficient and useful whereas non-polar solvents were not appropriate for this purpose (entries 6–13). Water as a green and eco-friendly solvent was the most privileged choice because the yield of the product in water was higher than all other solvents (entry 4).

In order to investigate the effect of temperature, the reaction was performed at different temperatures. The reaction result was not desirable at room temperature (25 °C) and the product yield was low after 9 h (entry 14). As a result of raising the temperature to 45 °C, the experimental data improved and the product yield increased by 72%, and the reaction time was reduced to 4 h (entry 15). Further raising the temperature to 55 °C significantly improved the product yield as well as reduced the reaction time (entry 4).

In order to study the catalytic activity of nanocomposite components in the reaction of styrene episulfide, sodium azide and phenylacetylene to give 2-phenyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)ethane-1-thiol, the reaction was evaluated separately using Fe3O4, SiO2, PMA, Cu, Fe3O4@SiO2 and Fe3O4@SiO2-PMA under the optimal conditions (Table 2). The results of the experiments indicated that although the fundamental catalytic role was played by copper nanoparticles, the presence of SiO2, Fe3O4 and PMA led to increase the efficiency and catalytic activity of the nanocomposite. The highest product yield was observed in the case of Fe3O4@SiO2-PMA-Cu nanocomposite. This could be caused by synergistic effect of all components of catalyst. Each component plays a unique role in increasing the activity and efficiency of the catalyst. Fe3O4 provides the magnetic properties for easy separation of catalyst. The silica layer protects the ferrite surface against oxidants and corrosive agents and also prevents aggregation of its particles. PMA offers a large porous surface with a wide range of coordination positions for anchoring the copper particles, and copper eventually catalyzes the cyclization of triazoles.

To evaluate the generalizability of the proposed synthetic method, the synthesis of 1,2,3-triazoles was examined using different thiiranes with electron donating and withdrawing substituents and cyclic thiiranes in the presence of phenyl acetylene, sodium azide and Fe3O4@SiO2-PMA-Cu nanocatalyst (Table 3, entries 1–8). Moreover, the reactivity of aliphatic terminal alkynes as well as 4-methoxyphenyl acetylene with styrene episulfide was investigated in this reaction and the results were satisfactory (entries 9–11). Different triazole derivatives were synthesized from the corresponding thiiranes in high yields without the formation of any by-products.

The catalyst recovery was evaluated under the optimized reaction conditions. The magnetic nanoparticles were first collected with a magnet, then thoroughly washed several times with ethyl acetate and distilled water. Having been washed, they were dried under air atmosphere and reused several times in successive cycles without losing their activity or magnetic property (Fig. 12). The VSM, XRD, FESEM and TEM techniques were used to confirm the structure of the recycled catalyst (Fig. 13). The data obtained from the recovered catalyst and the freshly prepared sample were compared. The results revealed that the catalyst morphology remained constant after several reuses. The ICP-OES analysis of the supernatant liquid after separating the catalyst was applied to determine the leaching extent of Fe, Mo, and Cu during the reaction, and according to the results, no traces of Fe, Mo and Cu metals were observed in the supernatant liquid.

Recycling of Fe3O4@SiO2-PMA-Cu in the synthesis of 2-phenyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)ethane-1-thiol.

(a) Magnetization curve, (b) XRD pattern, (c) FESEM and (d) TEM image of Fe3O4@SiO2-PMA-Cu in the synthesis of 2-phenyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)ethane-1-thiol after five cycles.

In order to confirm the heterogeneous nature of catalyst, a hot filtration test was carried out for reaction of styrene episulfide under the optimized conditions. For this purpose, the catalyst was filtered after 30 min at 100 °C and the filtrate was again transferred back into the reaction vessel and reaction was continued for further 3 h. However, no reaction was performed under these conditions and no triazole product was obtained, indicating the absence of copper particles in the reaction vessel. It shows that the copper nanoparticles played a catalytic role in the reaction. The extent of metal leaching during catalytic reaction was studied by ICPOES analysis of the supernatant liquid after removal of catalyst, and the result showed no presence of Cu metal in the supernatant liquid.

The synthesis of 1,2,3-triazole from thiiranes has not been reported so far, except in one recent case31. The advantages of the presented synthetic method were manifested by comparing the click reaction of styrene episulfide, phenyl acetylene and sodium azide with the other reported procedure in the literature. In viewpoints of temperature, reaction time, recoverability and product yield, the present procedure is more preferable. The reaction is performed in the presence of Fe3O4@SiO2-PMA-Cu in a shorter time and the product is obtained with higher yield. In addition, the need for a lower temperature to complete the reaction also indicates the higher efficiency of the new nanocatalyst (Table 4).

The proposed mechanism for synthesis of β-thiol-1,2,3-triazole consists of two possible pathways (A and B)31,75. In both paths, Fe3O4@SiO2-PMA-Cu plays the role of catalyst (Fig. 14). First, the catalyst facilitates the ring opening of thiirane and then accelerates 1,3-dipolar cycloaddition reaction and formation of triazoles. Pathway A shows that initially, a non-covalent interaction between metal and azide is created, followed by activation of thiirane ring with Fe3O4@SiO2-PMA-Cu catalyst. Then, azide is transferred from the catalyst to thiirane, and 2-azido-2-arylethanthiol is generated through the ring opening. At this stage, the thiirane rings bearing aryl substituents prefer to be opened from the more hindered position as the benzyl carbocation resulting from SN1 type of mechanism (α-cleavage) is more stable; however, the regioselective ring opening of thiiranes with alkyl and allyl groups is carried out from the less hindered carbon via SN2 type of mechanism (β-cleavage). In pathway A, in order to confirm the catalytic role of Fe3O4@SiO2-PMA-Cu in the preparation of 2-azido-2-arylethanthiol from styrene episulfide and sodium azide, the reaction was performed in the absence of catalyst, and only a very small amount of ring opened product was produced. During the reaction, gas chromatography (GC) and thin layer chromatography (TLC) runs of the reaction mixture were utilized to monitor the consumption of styrene episulfide and sodium azide and the formation of 2-azido-2-phenylethanthiol intermediate. FT-IR spectrum was used to characterize 2-azido-2-arylethanthiol through stretching frequency of 2097 cm−1 corresponding to the azide (Fig. 15a). In pathway B, first, phenylacetylene is activated through π-complexation with metal nanoparticles of catalyst to produce intermediate (I)76.The specific catalytic property of Fe3O4@SiO2-PMA-Cu is due to synergistic effect of all components. The formation of intermediate (I) was confirmed by characteristic absorption peak of 3293 cm−1 for phenylacetylene, indicating that terminal hydrogen atoms had not been removed during the activation process (Fig. 15b). Intermediate (II) is then obtained from in situ reaction of 2-azido-2-phenylethanthiol produced in pathway A and intermediate (I). Next, triazole (III) is formed from the 1,3-dipolar cycloaddition between azide and intermediate (II). The consumption of phenylacetylene as well as the vanishing of the 2-azido-2-arylethanthiol intermediate, were controlled through the GC and TLC of the reaction mixture. Finally, β-thiol-1,2,3-triazole (IV) was produced after the release of catalyst nanoparticles.

The proposed mechanism for the synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles in the presence of Fe3O4@SiO2-PMA-Cu nanocatalyst.

FT-IR spectra of (a) 2-azido-2-phenylethanthiol intermediate and (b) phenylacetylene.

In this research, the synthesis of novel, efficient, robust and reusable Fe3O4@SiO2-PMA-Cu magnetic nanocomposite was described. The new synthesized nanoparticles were characterized using various techniques such as FT-IR, XRD, VSM, EDS, XPS, TGA, BET, TEMand FESEM. Then, it was utilized as a practical catalyst for one-pot synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles from sodium azide, terminal alkynes, and diverse thiiranes in water. The synthesis of 1,2,3-triazole from thiiranes has not been reported so far, except in one case. The mentioned protocol offers several advantages such as reusability and easy separation of the heterogeneous magnetic catalyst, perfect regioselectivity, short reaction times, high product yields, utilizing of the green solvent and simple work-up procedure.

All reagents and substrates were bought with high quality without any need for further purification from Aldrich (Gallarate, Milan) and Merck (Darmstadt, Germany) Chemical Companies. The prepared nanocatalyst was identified by TEM images recorded using an EM10C-100 kV series microscope from Zeiss Company (Germany). FESEM images were obtained employing FESEM-TESCAN. The elemental composition study was performed using the energy dispersive X-ray spectrometer (EDS) analysis on a MIRA3 FE-SEM microscope (TESCAN, Czech Republic), equipped with an EDS detector (Oxford Instruments, UK). The XRD intensities were measured on a Bruker D8-Advanced diffractometer (Cu-Kα radiation, λ = 1.54056 Å). Magnetic property of nanocatalyst was evaluated by VSM (Meghnatis Daghigh Kavir Co., Kashan Kavir, Iran) at room temperature. The amount of copper in the catalyst was measured by Perkin Elmer Optima 7300DV ICP-OES analyzer. IR spectra of the catalyst and triazole products were recorded on Thermo Nicolet Nexus 670 FT-IR. 1H/13C NMR spectra of products were recorded on a Brucker 500 MHz spectrometer in deuteriochloroform with tetramethylsilane as internal standard. HRMS analyses were carried out in the electron impact mode (EI) at 70 eV. Melting points were also determined on an Electrothermal IA9100 microscopic digital melting point device. Brunauer–Emmett–Teller (BET) surface areas were measured by nitrogen adsorption at 77.35 K on Belsorp-max, BEL Japan. The electronic states of the samples were analyzed using X-ray photoelectron spectroscopy (XPS; Kratos-AXIS ULTRA DLD, Al-Kα x-ray source). thermogravimetric analysis (TGA) was determined on Perkin Elmer, Diamond TG/DTA.

Fe3O4 MNPs were prepared by a solid-state method based on the reported research31. In a typical experiment, FeCl2·4H2O (0.398 g, 2 mmol), FeCl3·6H2O (1.08 g, 4 mmol), NaOH (0.64 g, 16 mmol), and NaCl (0.232 g, 4 mmol) were blended in a mortar and then were milled for 50 min. The beginning of the reaction was accompanied by the release of heat. After a few minutes, the dark brown paste was obtained. The excess salt of the resulting mixture was removed through repeated rinsing with distilled water. The obtained product was placed in oven at 80 °C for 2 h, and then purified by calcination at 700 °C for 1.5 h to produce the dark brown powder of Fe3O4 MMPs.

Silica coated MNPs of Fe3O4@SiO2 were synthesized through an improved sol–gel method67. In a typical procedure, 0.5 g Fe3O4 MNPs was added to a mixed solution of ethanol (50 mL), distilled water (10 mL) and NH3·H2O (2.5 mL, 25%) and dispersed using ultrasonication for 1.5 h. Then 1.5 mL TEOS (tetraethyl orthosilicate) was added dropwise to the above mixture and sonicated for a further 15 min. After ongoing stirring at room temperature for 24 h, the yellow Fe3O4@SiO2 MNPs were accumulated, repeatedly washed with double distilled water and dried in an oven at 100 °C for 22 h.

In order to synthesize the phosphomolybdic acid (PMA) immobilized on the surface of Fe3O4@SiO2 nanoparticles, Fe3O4@SiO2 (0.5 g) was first suspended in ethanol (20 mL) and then dispersed by ultrasound for 30 min. Next, the solution of PMA (0.5 g) in ethanol (5 mL) was prepared and gently added dropwise to the suspension. The resulting brick-red mixture was stirred for 30 h under inert atmosphere of nitrogen while heating at 80 °C. The magnetic nanocomposite of Fe3O4@SiO2-PMA was collected by a magnet, washed several times with distilled water and dried at 60 °C for 20 h. The Fe3O4@SiO2-PMA nanocomposite was obtained as a soft brick-red powder.

To anchor the copper nanoparticles on the Fe3O4@SiO2-PMA, first, CuCl2·2H2O (0.68 g, 4 mmol) was dissolved in distilled water (50 mL) and then 1 g Fe3O4@SiO2-PMA was added to it and the mixture was stirred vigorously for 30 min. Next, 0.1 g potassium borohydride powder (KBH4) was gradually added to the mixture at room temperature and stirred for 1 h to reduce Cu2+ cations to copper nanoparticles. The obtained Fe3O4@SiO2-PMA-Cu nanocomposite was washed three times with double distilled water and after drying under air atmosphere, it was collected as a dark brick-red powder.

Different thiiranes bearing electron-donating or -withdrawing substituents were synthesized using previously reported procedure77. In a typical experiment, a mixture of epoxide (1 mmol) and alumina supported thiourea (0.8 g, 25% w/w) was placed in an agate mortar and milled for the required time at room temperature. The reaction completion was tracked by TLC utilizing n-hexane/ethylacetate (10:2) eluent. After the reaction was finished, the contents of the mortar were washed with ethylacetate and then filtered. The solvent containing thiirane was evaporated to produce the pure thiirane as a pale yellow oil.

To a prepared mixture of thiirane (1 mmol), terminal alkyne (1 mmol), NaN3 (0.078 g, 1.2 mmol) and H2O (5 mL) in a round-bottomed flask, equipped with a magnetic stirrer and condenser, 0.1 g of Fe3O4@SiO2-PMA-Cu nanocomposite was added. The mixture was stirred at 55 ºC for an appropriate time period (1.5–3.5 h). The reaction process was tracked using TLC and n-hexane/ethylacetate (10:2) eluent solvent. After the reaction ended, the Fe3O4@SiO2-PMA-Cu nanoparticles were accumulated utilizing an external magnet and reused in the consecutive cycle. After extraction of the aqueous layer with ethyl acetate and drying over anhydrous sodium sulfate, the organic solvent was evaporated under vacuum and the crude 1,2,3-triazoles were produced. The obtained products were recrystallized with EtOH/H2O (1:1) to give the pure β-thiol-1,4-disubstituted-1,2,3-triazoles in 85–98% yield (Table 2). The structure of the products was confirmed using HRMS (EI), 1H NMR, 13C NMR and FT-IR techniques. The spectra of the products as well as their spectral information are given in the supplementary section.

In order to recycle the catalyst, first, magnetic nanoparticles were collected utilizing an external magnet, washed three times with ethyl acetate and distilled water, and dried under air atmosphere. The dried nanoparticles of Fe3O4@SiO2-PMA-Cu were reused in the next cycle without any significant loss of catalytic activity or magnetic properties.

All data from this study are included in the article and the Supplementary Information File.

Ramos, L. M., Rodrigues, M. O. & Neto, B. A. D. Mechanistic knowledge and noncovalent interactions as the key features for enantioselective catalysed multicomponent reactions: A critical review. Org. Biomol. Chem. 17, 7260–7269 (2019).

Das, K. K., Manna, S. & Panda, S. Transition metal catalyzed asymmetric multicomponent reactions of unsaturated compounds using organoboron reagents. Chem. Commun. 57, 441–459 (2021).

Biesen, L. & Müller, T. J. J. Multicomponent and one-pot syntheses of quinoxalines. Adv. Synth. Catal. 363, 980–1006 (2021).

Insuasty, D., Castillo, J., Becerra, D., Rojas, H. & Abonia, R. Synthesis of biologically active molecules through multicomponent reactions. Molecules 25, 505 (2020).

Article  PubMed Central  CAS  Google Scholar 

Neochoritis, C. G., Zarganes-Tzitzikas, T., Katsampoxaki-Hodgetts, K. & Dömling, A. Multicomponent reactions: “Kinderleicht”. J. Chem. Educ. 97, 3739–3745 (2020).

Article  CAS  PubMed  PubMed Central  Google Scholar 

Chen, M. D., Lu, S. J., Yuag, G. P., Yang, S. Y. & Du, X. L. Synthesis and antibacterial activity of some heterocyclic β-enamino ester derivatives with 1,2,3-triazole. Heterocycl. Commun. 6, 421–426 (2000).

Sherement, EA, Tomanov, RI, Trukhin, EV & Berestovitskaya, VM Synthesis of 4-aryl-5-nitro-1,2,3-triazoles.Russ.J. Org.Chem.40, 594–595 (2004).

Ravi, G., Nath, A. R., Nagaraj, A., Damodhar, S. & Rao, G. N. Synthesis and antibacterial activity of 3-(5-methyl-1-phenyl-1H-1, 2, 3-triazol-4-yl)-6-aryl-7H-[1, 2, 4] triazolo [3, 4-b][1, 3, 4] thiadiazine. Der Pharma Chem. 6, 223–232 (2014).

Menendez, C. et al. Chemical synthesis and biological evaluation of triazole derivatives as inhibitors of InhA and antituberculosis agents. Eur. J. Med. Chem. 52, 275–283 (2012).

Article  CAS  PubMed  Google Scholar 

Hafez, H. N., Abbas, H. A. & El-Gazzar, A. R. Synthesis and evaluation of analgesic, anti-inflammatory and ulcerogenic activities of some triazolo- and 2-pyrazolyl-pyrido[2,3-d]-pyrimidines. Acta Pharm. 58, 359–378 (2008).

Article  CAS  PubMed  Google Scholar 

Banu, K. M., Dinaker, A. & Ananthnarayan, C. Synthesis, characterization, antimicrobial studies and pharmacological screening of some substituted 1, 2, 3-triazoles. Indian J. Pharm. Sci. 61, 202–205 (1999).

Kamal, A. et al. Synthesis and anticancer activity of chalcone-pyrrolobenzodiazepine conjugates linked via 1,2,3-triazole ring side-armed with alkane spacers. Eur. J. Med. Chem. 46, 3820–3831 (2011).

Article  ADS  CAS  PubMed  Google Scholar 

Silva, F. C. et al. Synthesis, HIV-RT inhibitory activity and SAR of 1-benzyl-1H-1,2,3-triazole derivatives of carbohydrates. Eur. J. Med. Chem. 44, 373–383 (2009).

Sangshetti, J. N., Nagawade, R. R. & Shinde, D. B. Synthesis of novel 3-(1-(1-substituted piperidin-4-yl)-1H-1,2,3-triazol-4-yl)-1,2,4-oxadiazol-5(4H)-one as antifungal agents. Bioorg. Med. Chem. Lett. 19, 3564–3567 (2009).

Article  CAS  PubMed  Google Scholar 

Palhagen, S. et al. Rufinamide: A double-blind, placebo-controlled proof of principle trial in patients with epilepsy. Epilepsy Res. 43, 115–124 (2001).

Article  CAS  PubMed  Google Scholar 

Guan, L. P., Jin, Q. H., Tian, G. R., Chai, K. Y. & Quan, Z. S. Synthesis of some quinoline-2(1H)-one and 1, 2, 4 - triazolo [4, 3 -a ]quinoline derivatives as potent anticonvulsants. J. Pharm. Sci. 10, 254–262 (2007).

Manfredini, S. et al. Pyrazolo-triazoles as light activable dna cleaving agents. Bioorg. Med. Chem. 8, 2343–2346 (2000).

Article  CAS  PubMed  Google Scholar 

Mady, M. F., Awad, G. E. A. & Jørgensen, K. B. Ultrasound-assisted synthesis of novel 1,2,3-triazoles coupled diaryl sulfone moieties by the CuAAC reaction, and biological evaluation of them as antioxidant and antimicrobial agents. Eur. J. Med. Chem. 84, 433–443 (2014).

Article  CAS  PubMed  Google Scholar 

Raj, R. et al. Azide-alkyne cycloaddition en route to 1H-1,2,3-triazole-tethered 7-chloroquinoline-isatin chimeras: Synthesis and antimalarial evaluation. Eur. J. Med. Chem. 62, 590–596 (2013).

Article  CAS  PubMed  Google Scholar 

Kim, T. W. et al. Synthesis and biological evaluation of phenyl-1H-1,2,3-triazole derivatives as anti-inflammatory agents. Bioorg. Chem. 59, 1–11 (2015).

Article  PubMed  CAS  Google Scholar 

Alonso, F., Moglie, Y., Radivoy, G. & Yus, M. Multicomponent click synthesis of 1,2,3-triazoles from epoxides in water catalyzed by copper nanoparticles on activated carbon. J. Org. Chem. 76, 8394–8405 (2011).

Article  CAS  PubMed  Google Scholar 

Alonso, F., Moglie, Y., Radivoy, G. & Yus, M. Multicomponent synthesis of 1,2,3-triazoles in water catalyzed by copper nanoparticles on activated carbon. Adv. Synth. Catal. 352, 3208–3214 (2010).

Sharghi, H., Beyzavi, M. H., Safavi, A., Doroodmand, M. M. & Khalifeh, R. Immobilization of porphyrinatocopper nanoparticles onto activated multi-walled carbon nanotubes and a study of its catalytic activity as an efficient heterogeneous catalyst for a click approach to the three-component synthesis of 1,2,3-triazoles in water. Adv. Synth. Catal. 351, 2391–2410 (2009).

Yadav, J. S., Reddy, B. V. S., Reddy, G. M. & Chary, D. N. Three component, regioselective, one-pot synthesis of β-hydroxytriazoles from epoxides via ‘click reactions’. Tetrahedron Lett. 48, 8773–8776 (2007).

Boningari, T., Olmos, A., Reddy, B. M., Sommer, J. & Pale, P. Zeo-click chemistry: Copper(I)–zeolite-catalyzed cascade reaction; one-pot epoxide ring-opening and cycloaddition. Eur. J. Org. Chem. 2010, 6338–6347 (2010).

Sharghi, H., Hosseini-Sarvari, M., Moeini, F., Khalifeh, R. & Beni, A. S. One-pot, three-component synthesis of 1-(2-hydroxyethyl)-1H-1,2,3-triazole derivatives by copper-catalyzed 1,3-dipolar cycloaddition of 2-azido alcohols and terminal alkynes under mild conditions in water. Helv. Chim. Acta. 93, 435–449 (2010).

Anil Kumar, B. S. P. et al. Synthesis of β-hydroxy-1,4-disubstituted-1,2,3-triazoles catalyzed by copper ferrite nanoparticles in tap water using click chemistry. RSC Adv. 4, 60652–60657 (2014).

Article  ADS  CAS  Google Scholar 

Naeimi, H. & Nejadshafiee, V. Efficient one-pot click synthesis of β-hydroxy-1,2,3-triazoles catalyzed by copper(i)@phosphorated SiO2 via multicomponent reaction in aqueous media. New J. Chem. 38, 5429–5435 (2014).

Esmaeili-Shahri, H., Eshghi, H., Lari, J. & Rounaghi, S. A. Click approach to the three-component synthesis of novel β-hydroxy-1,2,3-triazoles catalysed by new (Cu/Cu2O) nanostructure as a ligand-free, green and regioselective nanocatalyst in water. Appl. Organomet. Chem. 32, e3947 (2018).

Maleki, A., Panahzadeh, M. & Eivazzadeh-keihan, R. Agar: A natural and environmentally-friendly support composed of copper oxide nanoparticles for the green synthesis of 1,2,3-triazoles. Green Chem. Lett. Rev. 12, 395–406 (2019).

Eisavi, R. & Naseri, K. Preparation, characterization and application of MgFe2O4/Cu nanocomposite as a new magnetic catalyst for one-pot regioselective synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles. RSC Adv. 11, 13061–13076 (2021).

Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

Gptar, A. K. & Gupta, M. Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications. Biomaterials 26, 3995–4021 (2005).

Eivazzadeh-Keihan, R. et al. A novel biocompatible core-shell magnetic nanocomposite based on cross-linked chitosan hydrogels for in vitro hyperthermia of cancer therapy. Int. J. Biol. Macromol. 140, 407–414 (2019).

Article  CAS  PubMed  Google Scholar 

Ahghari, M. R., Soltaninejad, V. & Maleki, A. Synthesis of nickel nanoparticles by a green and convenient method as a magnetic mirror with antibacterial activities. Sci. Rep. 10, 12627 (2020).

Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

Mou, F., Guan, J., Ma, H., Xu, L. & Shi, W. Magnetic iron oxide chestnutlike hierarchical nanostructures: Preparation and their excellent arsenic removal capabilities. ACS Appl. Mater. Interfaces. 4, 3987–3993 (2012).

Article  CAS  PubMed  Google Scholar 

Maleki, A., Niksefat, M., Rahimi, J. & Taheri-Ledari, R. Multicomponent synthesis of pyrano[2,3-d]pyrimidine derivatives via a direct one-pot strategy executed by novel designed copperated Fe3O4@polyvinyl alcohol magnetic nanoparticles. Mater. Today Chem. 13, 110–120 (2019).

Maleki, A. & Firouzi-Haji, R. L-Proline functionalized magnetic nanoparticles: A novel magnetically reusable nanocatalyst for one-pot synthesis of 2,4,6-triarylpyridines. Sci. Rep. 8, 17303 (2018).

Article  ADS  PubMed  PubMed Central  CAS  Google Scholar 

Maleki, A., Hassanzadeh-Afruzi, F., Varzi, Z. & Esmaeili, M. S. Magnetic dextrin nanobiomaterial: An organic-inorganic hybrid catalyst for the synthesis of biologically active polyhydroquinoline derivatives by asymmetric Hantzsch reaction. Mater. Sci. Eng. C 109, 110502 (2020).

Maleki, A., Movahed, H., Ravaghi, P. & Kari, T. Facile in situ synthesis and characterization of a novel PANI/Fe3O4/Ag nanocomposite and investigation of catalytic applications. RSC Adv. 6, 98777–98787 (2016).

Article  ADS  CAS  Google Scholar 

Maleki, A., Hajizadeh, Z. & Salehi, P. Mesoporous halloysite nanotubes modified by CuFe2O4 spinel ferrite nanoparticles and study of its application as a novel and efficient heterogeneous catalyst in the synthesis of pyrazolopyridine derivatives. Sci. Rep. 9, 5552 (2019).

Article  ADS  PubMed  PubMed Central  CAS  Google Scholar 

Hajizadeh, Z., Radinekiyan, F., Eivazzadeh-keihan, R. & Maleki, A. Development of novel and green NiFe2O4/geopolymer nanocatalyst based on bentonite for synthesis of imidazole heterocycles by ultrasonic irradiations. Sci. Rep. 10, 11671 (2020).

Article  CAS  PubMed  PubMed Central  Google Scholar 

Maleki, A., Taheri-Ledari, R. & Soroushnejad, M. Surface functionalization of magnetic nanoparticles via palladium-catalyzed Diels–Alder approach. ChemistrySelect 3, 13057–13062 (2018).

Kazemi, M. & Mohammadi, M. Magnetically recoverable catalysts: Catalysis in synthesis of polyhydroquinolines. Appl. Organomet. Chem. 34, e5400 (2020).

Mohammadi, M. & Ghorbani-Choghamarani, A. Synthesis and characterization of novel hercynite@sulfuric acid and its catalytic applications in the synthesis of polyhydroquinolines and 2,3-dihydroquinazolin-4(1H)-ones. RSC Adv. 12, 2770–2787 (2022).

Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

Ghobakhloo, F., Azarifar, D., Mohammadi, M., Keypour, H. & Zeynali, H. Copper (II) schiff-base complex modified Uio-66-NH2(Zr) metal–organic framework catalyst for knoevenagel condensation–michael addition–cyclization reactions. Inorg. Chem. 61, 4825–4841 (2022).

Article  CAS  PubMed  Google Scholar 

Mohammadi , M. , Khodamorady , M. , Tahmasbi , B. , Bahrami , K. & Ghorbani-Choghamarani , A. Boehmite nanoparticles as versatile support for organic–inorganic hybrid materials: Synthesis, functionalization, and applications in eco-friendly catalysis .J. Ind.Eng.Chem.Rev. 97, 1–78 (2021).

Esam, Z., Akhavan, M., Bekhradnia, A., Mohammadi, M. & Tourani, S. A Novel magnetic immobilized para-aminobenzoic acid-Cu(II) complex: A green, efficient and reusable catalyst for aldol condensation reactions in green Media. Catal. Lett. 150, 3112–3131 (2020).

Wang, T. et al. Controllable synthesis of hierarchical porous Fe3O4 particles mediated by poly(diallyldimethylammonium chloride) and their application in arsenic removal. ACS Appl. Mater. Interfaces 5, 12449–12459 (2013).

Article  CAS  PubMed  Google Scholar 

Saiz, J., Bringas, E. & Ortiz, I. Functionalized magnetic nanoparticles as new adsorption materials for arsenic removal from polluted waters. J. Chem. Technol. Biotechnol. 89, 909–918 (2014).

Kumar, M. et al. Review on magnetic nanoferrites and their composites as alternatives in waste water treatment: Synthesis, modifications and applications. Environ. Sci. Water Res. Technol. 6, 491–514 (2020).

Cherevan, A. S. et al. Polyoxometalates on functional substrates: Concepts, synergies, and future perspectives. Adv. Sci. 7, 1903511 (2020).

Zhu, Y. et al. A cost-effective commercial soluble oxide cluster for highly efficient and stable organic solar cells. J. Mater. Chem. A 2, 1436–1442 (2014).

Ji, H. et al. Phosphomolybdic acid immobilized on ionic liquid-modified hexagonal boron nitride for oxidative desulfurization of fuel. RSC Adv. 7, 54266–54276 (2017).

Article  ADS  CAS  Google Scholar 

Kim, Y. & Shanmugam, S. Polyoxometalate–reduced graphene oxide hybrid catalyst: Synthesis, structure, and electrochemical properties. ACS Appl. Mater. Interfaces. 5, 12197–12204 (2013).

Article  CAS  PubMed  Google Scholar 

Li, J., Wang, X. H., Zhu, W. M. & Cao, F. H. Zn1.2H0.6PW1.2O40 nanotubes with double acid sites as heterogeneous catalysts for the production of biodiesel from waste cooking oil. ChemSusChem. 2, 177–183 (2009).

Article  CAS  PubMed  Google Scholar 

Grinenval, E. et al. Controlled interactions between anhydrous keggin-type heteropolyacids and silica support: Preparation and characterization of well-defined silica-supported polyoxometalate species. J. Phys. Chem. C 114, 19024–19034 (2010).

Suppes, G. M., Deore, B. A. & Freund, M. S. Porous conducting polymer/heteropolyoxometalate hybrid material for electrochemical supercapacitor applications. Langmuir 24, 1064–1069 (2008).

Article  CAS  PubMed  Google Scholar 

Kholdeeva, O. A. et al. Co-containing polyoxometalate-based heterogeneous catalysts for the selective aerobic oxidation of aldehydes under ambient conditions. J. Catal. 226, 363–371 (2004).

Zhang, L., Yang, Y., Ziaee, M. A., Lu, K. & Wang, R. Nanohybrid of carbon quantum dots/molybdenum phosphide nanoparticle for efficient electrochemical hydrogen evolution in alkaline medium. ACS Appl. Mater. Interfaces 10, 9460–9467 (2018).

Article  CAS  PubMed  Google Scholar 

Ensafi, A. A., Heydari-Soureshjani, E. & Rezaei, B. Nanostructure polyoxometalates containing Co, Ni, and Cu as powerful and stable catalysts for hydrogen evolution reaction in acidic and alkaline solutions. Int. J. Hydrog. Energy 42, 5026–5034 (2017).

Ji, Y., Huang, L., Hu, J., Streb, C. & Song, Y. Polyoxometalate-functionalized nanocarbon materials for energy conversion, energy storage and sensor systems. Energy Environ. Sci. 8, 776–789 (2015).

Hassanzadeh, S., Eisavi, R. & Abbasian, M. Preparation and characterization of magnetically separable MgFe2O4/Mg(OH)2 nanocomposite as an efficient heterogeneous catalyst for regioselective one-pot synthesis of β-chloroacetates from epoxides. Appl. Organomet. Chem. 32, e4520 (2018).

Eisavi, R. & Alifam, S. ZnFe2O4 nanoparticles: A green and recyclable magnetic catalyst for fast and regioselective conversion of epoxides to vicinal hydroxythiocyanates using NH4SCN under solvent-free conditions. Phosphorus Sulfur Silicon 193, 211–217 (2017).

Eisavi, R., Ghadernejad, S., Zeynizadeh, B. & Aminzadeh, F. M. Magnetically separable nano CuFe2O4: An efficient and reusable heterogeneous catalyst for the green synthesis of thiiranes from epoxides with thiourea. J. Sulfur. Chem. 37, 537–545 (2016).

Eisavi, R., Ahmadi, F., Ebadzade, B. & Ghadernejad, S. A green method for solvent-free conversion of epoxides to thiiranes using NH4SCN in the presence of NiFe2O4 and MgFe2O4 magnetic nanocatalysts. J. Sulfur. Chem. 38, 614–624 (2017).

Hassanzadeh, S., Eisavi, R. & Abbasian, M. Green synthesis of thiiranes from epoxides catalyzed by magnetically separable CuFe2O4/Mg(OH)2 nanocomposite in water under benign conditions. J. Sulfur. Chem. 40, 240–255 (2019).

Mahmoudzadeh, M., Mehdipour, E. & Eisavi, R. MgFe2O4@SiO2-PrNH2/Pd/bimenthonoxime core-shell magnetic nanoparticles as a recyclable green catalyst for heterogeneous Suzuki cross-coupling in aqueous ethanol. J. Coord. Chem. 72, 841–859 (2019).

Eisavi, R. & Karimi, A. CoFe2O4/Cu(OH)2 magnetic nanocomposite: An efficient and reusable heterogeneous catalyst for one-pot synthesis of β-hydroxy-1,4-disubstituted-1,2,3-triazoles from epoxides. RSC Adv. 9, 29873–29887 (2019).

Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

Khadempir, S. et al. A polyoxometalate-assisted approach for synthesis of Pd nanoparticles on graphene nanosheets: Synergistic behaviour for enhanced electrocatalytic activity. RSC Adv. 5, 24319–24326 (2015).

Article  ADS  CAS  Google Scholar 

Zhang, B. et al. Stabilizing a platinum1 single-atom catalyst on supported phosphomolybdic acid without compromising hydrogenation activity. Angew Chem. Int. Ed. 128, 8319–8323 (2016).

Maleki, B. et al. Silica coated magnetic NiFe2O4 nanoparticle supported phosphomolybdic acid; synthesis, preparation and its application as a heterogeneous and recyclable catalyst for the one-pot synthesis of tri- and tetra-substituted imidazoles under solvent free conditions. RSC Adv. 5, 64850–64857 (2015).

Article  ADS  CAS  Google Scholar 

Loh, K. S., Lee, Y. H., Musa, A, Salmah, A. A. & Zamri, I. Use of Fe3O4 nanoparticles for enhancement of biosensor response to the herbicide 2,4-dichlorophenoxyacetic acid. Sensors 8, 5775–5791(2008).

Ingavale, S. B. et al. Polyoxomolybdate anchored graphite oxide: Noble metal-free electrocatalyst for oxygen reduction reaction. Int J. Hydrog. Energy 44, 24922–24933 (2019).

Gao, A. et al. Synthesis of Fe3O4@SiO2-Au/Cu magnetic nanoparticles and its efficient catalytic performance for the Ullmann coupling reaction of bromamine acid. Chin. Chem. Lett. 29, 1301–1304 (2018).

Sharghi, H., Khoshnood, A., Doroodmand, M. M. & Khalifeh, R. 1,4-Dihydroxyanthraquinone-copper(II) nanoparticles immobilized on silica gel: A highly efficient, copper scavenger and recyclable heterogeneous nanocatalyst for a click approach to the three-component synthesis of 1,2,3-triazole derivatives in water. J. Iran. Chem. Soc. 9, 231–250 (2012).

Fang, Y. et al. Insight into the mechanism of the CuAAC reaction by capturing the crucial Au4Cu4−π-alkyne intermediate. J. Am. Chem. Soc. 143, 1768–1772 (2021).

Article  CAS  PubMed  Google Scholar 

Eisavi, R. & Zeynizadeh, B. A green protocol for rapid and efficient conversion of epoxides to thiiranes using alumina immobilized thiourea at solvent-free conditions. Phosphorus Sulfur Silicon 191, 65–69 (2016).

The financial support of this work by the Research Council of Payame Noor University is gratefully acknowledged.

Department of Chemistry, Payame Noor Universtiy (PNU), P.O. BOX 19395-4697, Tehran, Iran

Ronak Eisavi & Fereshteh Ahmadi

You can also search for this author in PubMed  Google Scholar

You can also search for this author in PubMed  Google Scholar

R.E. supervised the study, designed the research framework and carried out the data analysis. F.A. conducted experiments. The final manuscript has been written by R.E. with contributions from F.A.

The authors declare no competing interests.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, 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 changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. 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

Eisavi, R., Ahmadi, F. Fe3O4@SiO2-PMA-Cu magnetic nanoparticles as a novel catalyst for green synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles. Sci Rep 12, 11939 (2022).


Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Scientific Reports (Sci Rep) ISSN 2045-2322 (online)

Fe3O4@SiO2-PMA-Cu magnetic nanoparticles as a novel catalyst for green synthesis of β-thiol-1,4-disubstituted-1,2,3-triazoles | Scientific Reports

Iron Oxide Yellow 313 Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.