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Öğe A promising nanocatalyst: Upgraded Kraft lignin by titania and palladium nanoparticles for organic dyes reduction(Elsevier B.V., 2021) Nezafat, Zehra; Mohazzab, Bahareh Feizi; Jaleh, Babak; Nasrollahzadeh, Mahmoud; Baran, Talat; Shokouhimehr, MohammadrezaThe evaluation of dye degradation was adorned a great interest due to scarcity of water, courtesy of industrialization. Here, Kraft lignin was upgraded by immobilization of TiO2 nanoparticles (NPs) by the reflux method (KL-T). Palladium (Pd) NPs were produced in a promising way by laser ablation in liquid (LAL) and loaded on KL-T to prepare an efficient nanocatalyst (KL-T/Pd). The synthesized KL-T/Pd is characterized by X-ray diffraction (XRD), Fourier transforms infrared (FT-IR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectrometry (EDX), and Transmission electron microscope (TEM) analyses. The KL-T/Pd nanocomposite was applied as an efficient and novel nanocatalyst for the reduction of methylene blue (MB) and methyl orange (MO) by NaBH4 as a reducing agent in aqueous media at ambient temperature. Our experimental results displayed that the 1 mg of KL-T/Pd catalyst can be reduced MB and MO organic dyes within 23 and 8 s, respectively at room temperature. The KL-T/Pd nanocatalyst can be recycled and reused four times with no considerable loss of performance. Having different advantages such as high catalytic performance, safe synthesis method, and high stability, lignin was suggested as a natural substrate.Öğe Bentonite-supported furfural-based Schiff base palladium nanoparticles: an efficient catalyst in treatment of water/wastewater pollutants(Springer, 2020) Nasrollahzadeh, Mahmoud; Baran, Talat; Sajjadi, Mohaddeseh; Yılmaz Baran, Nuray; Shokouhimehr, MohammadrezaThis study reports a versatile process for the fabrication of palladium nanoparticles (Pd NPs) stabilized on Schiff base modified Unye bentonite with a coordination performance of furfural ligand (UN-Fur@PdNPs) as a promising nanocatalyst in the reduction of organic/inorganic pollutants. APTES ((3-aminopropyl)triethoxysilane)-modified UN-Fur@PdNPs has been synthesized via a facile, multi-step procedure without any additional stabilizing/reducing agents. The characterization of UN-Fur@PdNPs sample was carried out by FTIR, XRD, EDS, elemental mapping, STEM, TEM, HRTEM, and TG/DTG analyses which indicate the formation of Pd NPs (~ 10 nm) on the surface of UN-Fur. The catalytic activity/stability of the as-prepared nanocatalyst has also been assessed in the reduction of 4-nitrophenol (4-NP), Congo Red (CR), Methylene Blue (MB), and Methyl Orange (MO) dyes by NaBH4 (sodium borohydride) and chromium [Cr(VI)] by HCOOH (formic acid) in water. Catalytic efficiency retention has also been obtained after eight cycles. UN-Fur@PdNPs showed excellent catalytic performance and high stability/sustainability in the reduction of all five targeted organic/inorganic pollutants.Öğe Cyanation of aryl halides and Suzuki-Miyaura coupling reaction using palladium nanoparticles anchored on developed biodegradable microbeads(Elsevier B.V., 2020) Baran, Talat; Nasrollahzadeh, MahmoudThis work reports i) green synthesis of palladium nanoparticles (Pd NPs) on the developed biodegradable microbeads as stabilizers, featuring chitosan, agarose and beta-cyclodextrin, ii) investigation of the catalytic role of the Pd NPs prepared in the Suzuki-Miyaura and iii) cyanation reactions. Pd NPs@microcapsules (CAP) convert a series of aryl halides to biphenyl compounds with yields ranging from 79 to 98%. Pd NPs@CAP is highly active in the cyanation of different aryl bromides and iodides using K4[Fe(CN)6] and is used to prepare benzonitriles with a yield of up to 97%. More importantly, Pd NPs@CAP is easily recovered from the reaction mixture and successfully reused seven consecutive times in the Suzuki-Miyaura and cyanation reactions. This significant features of Pd NPs@CAP are i) ease of purification of desired biaryls and benzonitriles and ii) production of no by-products in both catalytic reactionsÖğe Efficient degradation of environmental contaminants using Pd-RGO nanocomposite as a retrievable catalyst(Springer, 2020) Nasrollahzadeh, Mahmoud; Jaleh, Babak; Baran, Talat; Varma, Rajender S.Abstract: Pd nanoparticles (NPs)/reduced graphene oxide (RGO) nanocomposite was prepared in a one-pot process by using Euphorbia stenoclada extract as antioxidant media in the absence of any surfactant, dangerous reactants or using external energy input. Catalytic potential of the fabricated Pd-RGO nanocomposite was examined for the degradation of environmental contaminants including Cr(VI), 4-nitrophenol (4-NP), Congo red (CR), methylene blue (MB) and methyl orange (MO). The Pd-RGO nanocomposite has been thoroughly characterized by employing X-ray diffraction, UV–Vis and TEM studies. Furthermore, recyclability and reusability aspects of the nanocomposite were monitored for multiple uses without much change in catalytic activity. Graphic abstract: [Figure not available: see fulltext.].Öğe Facile fabrication of magnetically separable palladium nanoparticles supported on modified kaolin as a highly active heterogeneous catalyst for Suzuki coupling reactions(Elsevier Ltd, 2020) Baran, Talat; Nasrollahzadeh, MahmoudIn this study, Fe3O4 loaded Schiff base modified kaolin was prepared as a new support and palladium nanoparticles were anchored on it without any additional reducing agent (Pd NPs@Kao/Fe3O4/Pyr). Characterization studies demonstrated that Pd NPs@Kao/Fe3O4/Pyr was successfully designed and the size of particles was about 25 nm. Pd NPs@Kao/Fe3O4/Pyr was then utilized as catalyst in the preparation of biaryl compounds via Suzuki cross coupling reactions. Catalytic tests showed that Pd NPs@Kao/Fe3O4/Pyr acted as a highly active heterogeneous nanocatalyst in the coupling reaction of aryl iodides, bromides and chlorides containing different functional groups. Moreover, it was found that Pd NPs@Kao/Fe3O4/Pyr was successfully used in consecutive recycling tests and gave an 89% yield even after ten runs. In addition to the high catalytic behavior and reusability, Pd NPs@Kao/Fe3O4/Pyr have some advantages such as i) capability of application for various halides containing different functional groups, ii) ease of purification of final product and iii) simple work-up.Öğe Facile preparation of nanostructured Pd-Sch-delta-FeOOH particles: A highly effective and easily retrievable catalyst for aryl halide cyanation and p-nitrophenol reduction(Pergamon-Elsevıer Science, 2021) Çalışkan, Melike; Baran, Talat; Nasrollahzadeh, MahmoudIron based compounds are good candidates as supports to immobilize different transition metals due to their eco-friendly nature, capability of facilitating chemical modifications, inexpensiveness, high stability and easy recoverability. In this study, palladium nanoparticles (Pd NPs) were successfully stabilized on designed Schiff base modified delta-FeOOH particles as a highly effective and readily recoverable heterogeneous catalyst (Pd-Sch-delta-FeOOH nanocatalyst). The catalyst was fabricated via a facile multi-step approach without utilizing any additional reducing agents. The Pd-Sch-delta-FeOOH was characterized by Fourier transforms infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET). Characterization studies confirmed that the prepared small sized Pd NPs were spherically shaped and well dispersed on the surface of Schiff base modified delta-FeOOH. The catalytic efficiency of Pd-Sch-delta-FeOOH nanocatalyst was then tested in the preparation of benzonitriles through cyanation of aryl halides using K-4[Fe(CN)(6)] has been utilized as a cyanation agent and also reduction of p-nitrophenol (p-NP) using NaBH4 as the reducing agent. Benzonitriles were characterized using GC-MS. Catalytic studies showed that benzonitriles were obtained in good reaction yields in the presence of heterogeneous Pd-Sch-delta-FeOOH nanocatalyst (87-98%). It was found that Pd-Sch-delta-FeOOH was also a useful nanocatalyst for p-NP reduction at ambient temperature in eco-friendly media within 2 min. The reduction rate for p-NP with Pd-Sch-delta-FeOOH was measured via UV-Vis spectroscopy from 250 nm to 550 nm. Furthermore, Pd-Sch-delta-FeOOH nanocatalyst was able to remain active for six successive runs due to its recyclable/reusable nature.Öğe Facile synthesis of palladium nanoparticles immobilized on magnetic biodegradable microcapsules used as effective and recyclable catalyst in Suzuki-Miyaura reaction and p-nitrophenol reduction(Elsevier Ltd, 2019) Baran, Talat; Nasrollahzadeh, MahmoudThis study reports (i) preparation and characterization of palladium nanoparticles (Pd NPs) stabilized on magnetically separable chitosan/agar microcapsules (Pd NPs@Fe3O4/CS-AG microcapsules) and (ii) investigation of catalytic behaviors of the prepared nanoparticles in Suzuki-Miyaura C-C cross-coupling reactions and reduction of p-nitrophenol (p-NP). Fourier transforms infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), elemental mapping, inductively coupled plasma-optical emission spectrometry (ICP-OES) and thermogravimetry/derivative thermogravimetry (TG/DTG) techniques were used for analyzing the Pd NPs@Fe3O4/CS-AG microcapsules. Characterization studies showed that Pd NPs@Fe3O4/CS-AG microcapsules were successfully synthesized and the size of the particles was in the range of 28–39 nm. Pd NPs@Fe3O4/CS-AG microcapsules displayed highly effective catalytic performance in the conversion of various aryl halides into the corresponding biaryl derivatives by Suzuki-Miyaura reaction under solvent-free conditions in 5 min. Pd NPs@Fe3O4/CS-AG microcapsules were also successfully employed in p-NP reduction to p-aminophenol (p-AP) in water at room temperature in 180 s. Moreover, reproducibility studies showed that Pd NPs@Fe3O4/CS-AG microcapsules were highly efficient and could be used many times in both catalytic reactions due to their magnetically separable nature. According to the results of this work, Pd NPs@Fe3O4/CS-AG microcapsules are highly efficient, economical, practical and environmentally superb catalysts for Suzuki-Miyaura reaction and p-NP reduction. © 2019Öğe Facile synthesis of Pd nanoparticles supported on a novel Schiff base modified chitosan-kaolin: Antibacterial and catalytic activities in Sonogashira coupling reaction(Elsevier B.V., 2021) Nasrollahzadeh, Mahmoud; Shafiei, Nasrin; Baran, Talat; Pakzad, Khatereh; Tahsili, Mohammad Reza; Yılmaz Baran, Nuray; Shokouhimehr, MohammadrezaThe present work studies the Sonogashira coupling reaction (SCR) between aryl halides and acetylenes under aerobic conditions using the catalytic complex of Pd nanoparticles (NPs) supported on a novel Schiff base modified chitosan-kaolin (Pd NPs@CS-Kao) in ethanol solvent. The prepared catalyst was characterized by TEM, SEM, FT-IR, XRD, EDS, XPS, elemental mapping, and Raman analyses. The products were formed in high yields. At the end of the reaction, Pd NPs@CS-Kao can be filtered and reused for five consecutive cycles. The advantages of this catalytic process include simple methodology, high yields, and easy work-up. In addition, Pd NPs@CS-Kao exhibited effective antibacterial performance against E. coli gram-negative bacteria.Öğe Green synthesis of palladium nanocatalyst derived from the ?-cyclodextrin used as effective heterogeneous catalyst for cyanation of aryl halides(Elsevier B.V., 2020) Baran, Talat; Nasrollahzadeh, MahmoudIn this study, preparation of highly stable palladium nanoparticles (Pd NPs) on Schiff base modified ?-cyclodextrin (?-CD-Sch) in the absence of reducing agents has been successfully carried out. Pd NPs@?-CD-Sch has then been applied as nanocatalyst in the synthesis of benzonitriles via cyanation reaction using K4Fe(CN)6, which is a low cost, commercially available and non-toxic cyanide source. A series of benzonitriles containing different substrates were successfully fabricated with 77–98% yields using Pd NPs@?-CD-Sch. Moreover, Pd NPs@?-CD-Sch catalyst was quantitatively recovered and reutilized several times, showing good reaction yields. This work revealed that i) prepared ?-CD-Sch is an effective stabilizer for the fabrication of Pd NPs and ii) Pd NPs@?-CD-Sch catalyst play an important role in the fabrication of benzonitriles.Öğe Green synthesis of palladium nanocatalyst derived from the beta-cyclodextrin used as effective heterogeneous catalyst for cyanation of aryl halides(Elsevier, 2020) Baran, Talat; Nasrollahzadeh, MahmoudIn this study, preparation of highly stable palladium nanoparticles (Pd NPs) on Schiff base modified beta-cyclodextrin (beta-CD-Sch) in the absence of reducing agents has been successfully carried out. Pd NPs@beta-CD-Sch has then been applied as nanocatalyst in the synthesis of benzonitriles via cyanation reaction using K4Fe(CN)(6), which is a low cost, commercially available and non-toxic cyanide source. A series of benzonitriles containing different substrates were successfully fabricated with 77-98% yields using Pd NPs@beta-CD-Sch. Moreover, Pd NPs@beta-CD-Sch catalyst was quantitatively recovered and reutilized several times, showing good reaction yields. This work revealed that i) prepared beta-CD-Sch is an effective stabilizer for the fabrication of Pd NPs and ii) Pd NPs@beta-CD-Sch catalyst play an important role in the fabrication of benzonitriles.Öğe Hibiscus Rosasinensis L. aqueous extract-assisted valorization of lignin: Preparation of magnetically reusable Pd NPs@Fe3O4-lignin for Cr(VI) reduction and Suzuki-Miyaura reaction in eco-friendly media(Elsevier B.V., 2020) Nasrollahzadeh, Mahmoud; Bidgoli, Nayyereh Sadat Soheili; Issaabadi, Zahra; Baran, Talat; Ghavamifar, Zahra; Luque, RafaelHibiscus Rosasinensis L. extract mediated biosynthesis of Pd nanoparticles (NPs) and their deposition on the magnetic calcium lignosulfonate (MCaLig), as a simple and eco-friendly process for the preparation of Pd NPs@Fe3O4-lignin, is reported. The Pd NPs@Fe3O4-lignin was characterized by TEM, XRD, EDS, FE-SEM, FT-IR, VSM, and UV–Vis. The magnetic NPs were employed as exceptional catalysts in the catalytic reduction of Cr(VI) and Suzuki-Miyaura reaction between PhB(OH)2 and substituted aryl halides in EtOH:H2O as well as under ligand free conditions in the presence of K2CO3 with satisfactory product yields. Regeneration of the Pd NPs@Fe3O4-lignin was carried out by a magnet after the preparation of biphenyls. Catalytic efficiency retention was achieved after seven cycles.Öğe Modified chitosan-zeolite supported Pd nanoparticles: A reusable catalyst for the synthesis of 5-substituted-1H-tetrazoles from aryl halides(Elsevier B.V., 2022) Sajjadi, Mohaddeseh; Nasrollahzadeh, Mahmoud; Ghafuri, Hossein; Baran, Talat; Baran, Nuray Yılmaz; Orooji, Yasin; Shokouhimehr, MohammadrezaA novel heterogeneous catalyst has been developed using chitosan-zeolite supported Pd nanoparticles (PdNPs@CS-Zeo) and used in an efficient synthesis of 5-substituted-1H-tetrazoles from aryl halides with high yields for relatively short reaction times with an easy work-up procedure. In this method, highly effective and reusable PdNPs@CS-Zeo catalyst was used in the reaction of various aryl iodides/bromides with K4[Fe(CN)6] as a non-toxic cyanide source to catalyze the [2 + 3] cycloaddition of the corresponding aryl nitriles with NaN3 in the sequential one-pot preparation of 5-substituted-1H-tetrazoles. The synthesized PdNPs@CS-Zeo nanocatalyst was characterized using XRD, FTIR, TEM, HRTEM, XPS, Raman, TG-DTG, ICP-OES, BET, and EDS mapping. Additionally, the nanocatalyst could be effectively separated by filtration and reused for multiple times without significant decrease of catalytic activity.Öğe Nano-sized and microporous palladium catalyst supported on modified chitosan/cigarette butt composite for treatment of environmental contaminants(Elsevier, 2023) Baran, Talat; Karaoğlu, Kaan; Nasrollahzadeh, MahmoudThis study reports a versatile process for the fabrication of a microporous heterogeneous palladium nanocatalyst on a novel spherical, biodegradable, and chemically/physically resistant catalyst support consisting of chitosan (CS) and cigarette waste-derived activated carbon (CAC). The physicochemical properties of the microporous Pd-CS-CAC nanocatalyst developed were successfully determined by FTIR, XRD, FE-SEM, TEM, BET, and EDS techniques. TEM studies showed that the average particle size of the synthesized Pd NPs was about 30 nm. The catalytic prowess of microporous Pd-CS-CAC was evaluated in the reduction/decolorization of various nitroarenes (2-nitroaniline (2-NA), 4-nitroaniline (4-NA), 4-nitrophenol (4-NP), and 4-nitro-o-phenylenediamine (4-NPD)) and organic dyes (methyl red (MR), methyl orange (MO), methylene blue (MB), congo red (CR), and rhodamine B (RhB)) in an aqueous medium in the presence of NaBH4 as the reducing agent at room temperature. The catalytic activities were studied by UV-Vis absorption spectroscopy of the supernatant at regular time intervals. The short reaction times, mild reaction conditions, high efficiency (100% conversion), easy separation, and excellent chemical stability of the catalyst due to its heterogeneity and reusability are the advantages of this method. The results of the tests showed that reduction/decolorization reactions were successfully carried out within 10-140 s due to the good catalytic ability of Pd-CS-CAC. Moreover, Pd-CS-CAC was reused for 5 consecutive times with no loss of the initial shape, size, and morphology, confirming that it was a sustainable and robust nanocatalyst.Öğe Palladium nanoparticles stabilized on a novel Schiff base modified Unye bentonite: Highly stable, reusable and efficient nanocatalyst for treating wastewater contaminants and inactivating pathogenic microbes(Elsevier B.V., 2020) Sajjadi, Mohaddeseh; Baran, Nuray Yılmaz; Baran, Talat; Nasrollahzadeh, Mahmoud; Tahsili, Mohammadreza; Shokouhimehr, MohammadrezaEfficient decoration and characterization of highly catalytic, active Pd nanoparticles (NPs) onto a novel Schiff base modified Unye bentonite (UN-Sch) with high coordination performance of structurally defined 2-pyrrolaldehyde ligands against palladium ions (Pd NPs@UN) have been described. Amine modified UN/Pd NPs were fabricated via a facile multi-step approach without utilizing any additional reducing agents. To check the applicability of the synthesized Pd NPs@UN as highly active nanocatalysts in water and wastewater treatment, the reduction of highly toxic compounds such as 4-nitrophenol (4-NP), hexavalent chromium [Cr(VI)], Rhodamine B (RhB), potassium hexacyanoferrate(III) (K3[Fe(CN)6]) and congo red (CR) at ambient temperature in eco-friendly media has been investigated. The surface nature of Unye bentonite was altered after modification, leading to notable increase in the catalytic properties. The ensuing Pd NPs@UN demonstrated superior catalytic prowess (100% conversion within a few seconds for the aforementioned pollutants), excellent stability (~4 months) and superior recyclability (~96% yield after seven successive cycles). Notably, the present procedure is a clean and green one in which aqueous sodium borohydride (NaBH4) or formic acid (HCOOH) are used as reducing agents in the absence of any toxic reductants. Moreover, the results showed that Pd NPs@UN was effective against fungi and bacteria.Öğe Pd nanocatalyst stabilized on amine-modified zeolite: Antibacterial and catalytic activities for environmental pollution remediation in aqueous medium(Elsevier B.V., 2020) Nasrollahzadeh, Mahmoud; Baran, Talat; Baran, Nuray Yılmaz; Sajjadi, Mohaddeseh; Tahsili, Mohammadreza; Shokouhimehr, MohammadrezaIn this study, the immobilization of palladium nanoparticles (NPs) on amine modified zeolite (Zeo) particles bearing a heterocyclic ligand has been developed through immobilizing structurally defined furfural with long tail of 3-aminopropyltriethoxysilane. NH2 modified Zeo/Pd has been synthesized via facile multi-step organic amine functionalization as a sustainable, recoverable and highly active nanocatalyst in the reduction of hexavalent chromium [Cr(VI)], potassium hexacyanoferrate(III) (K3[Fe(CN)6]), 2,4-dinitrophenylhydrazine (2,4-DNPH), 4-nitrophenol (4-NP), Rhodamine B (RhB), Methylene Blue (MB) and Nigrosin (NS) at ambient temperature in aqueous media. The surface nature of zeolite was changed after NH2 modification, leading to a remarkable increase in the catalytic and antimicrobial performances. TEM and HRTEM (high resolution transmission electron microscopy), FESEM (field emission scanning electron microscopy), STEM (scanning transmission electron microscopy), TG-DTG (thermogravimetry/derivative thermogravimetry), FT-IR (Fourier transform infrared), XRD (X-ray diffraction), EDS (energy dispersive X-ray spectroscopy), elemental mapping, XPS (X-ray photoelectron spectroscopy) and Raman analyses have been used to characterize the as-prepared nanocatalyst. The high removal rates of these environmental pollutants with NH2 modified Zeo/Pd nanocatalyst (Pd NPs@Zeo) using sodium borohydride (NaBH4) and formic acid (HCOOH) at ambient temperature were measured via UV–Vis spectroscopy and the nanocatalyst could be reused at least eight times without any significant loss of catalytic activity.Öğe Pd nanoparticles loaded on modified chitosan-Unye bentonite microcapsules: A reusable nanocatalyst for Sonogashira coupling reaction(Elsevier Ltd, 2021) Shafiei, Nasrin; Nasrollahzadeh, Mahmoud; Baran, Talat; Yılmaz Baran, Nuray; Shokouhimehr, MohammadrezaThis work investigates the preparation of a catalytic complex of palladium nanoparticles supported on novel Schiff base modified chitosan-Unye bentonite microcapsules (Pd NPs@CS-UN). The complex has been characterized by FT-IR, EDS, XRD, TEM, HRTEM, Raman, ICP-OES and elemental mapping analyses. Pd NPs@CS-UN was used as a catalyst for Sonogashira coupling reactions between aryl halides and acetylenes, employing K2CO3 as the base and EtOH as a green solvent under aerobic conditions in which it showed high efficacy. Pd NPs@CS-UN was regenerated by filtration after the completion of the reaction. This catalytic process has many advantages including simple methodology, high yields, and easy work-up. The catalytic performance does not notably change even after five consecutive runs.Öğe Pd nanoparticles stabilized on the Schiff base-modified boehmite: Catalytic role in Suzuki coupling reaction and reduction of nitroarenes(Elsevier, 2019) Yılmaz Baran, Nuray; Baran, Talat; Nasrollahzadeh, Mahmoud; Varma, Rajender S.Palladium nanoparticles (Pd NPs) were decorated on Schiff base-modified boehmite (Sch-boehmite) particles via a simple method without deploying any additional reducing agents and their structure was confirmed by different characterization methods. The ensuing Pd NPs@Sch-boehmite was evaluated as a retrievable catalyst for multiple cycles in Suzuki cross-coupling reactions with extensive substrate tolerance to produce biaryls in high yields within 6 min, and the reduction of 2-nitroaniline (2-NA) and 4-nitrophenol (4-NP) at room temperature in 3e4 min, respectively. Moreover, Pd NPs@Sch-boehmite catalyst could be conveniently recovered and reused multiple times.Öğe Pd/CoFe2O4/chitosan: A highly effective and easily recoverable hybrid nanocatalyst for synthesis of benzonitriles and reduction of 2-nitroaniline(Elsevier, 2021) Baran, Talat; Nasrollahzadeh, MahmoudIn this study, a novel catalyst system with high activity and easy recoverability was successfully prepared through the deposition of Pd nanoparticles (NPs) onto designed sustainable hybrid beads containing magnetic cobalt ferrite and chitosan (Pd/CoFe2O4/chitosan). The catalytic potential of Pd/CoFe2O4/chitosan hybrid nanocatalyst was then assessed in i) preparation of benzonitriles via aryl halides cyanation and ii) reduction of 2nitroaniline (2-NA). Various aryl iodides and bromides were successfully cyanated by Pd/CoFe2O4/chitosan hybrid nanocatalyst with excellent reaction yields within 3 h. In addition to the production of benzonitriles, the hybrid nanocatalyst showed excellent activity by reducing 2-NA in 65 s. It was proved that the Pd/CoFe2O4/chitosan hybrid nanocatalyst outperformed many catalysts used in the cyanation of aryl halides and catalytic reduction of 2-NA previously reported in the literature. Moreover, it was found that the designed Pd/CoFe2O4/chitosan hybrid nanocatalyst was easily and effectively separated from the reaction mixture using an external magnet and reused several times in catalytic reactions without considerable loss of catalytic activity.Öğe Recent advances in polymer supported palladium complexes as (nano)catalysts for Sonogashira coupling reaction(Elsevier, 2020) Nasrollahzadeh, Mahmoud; Motahharifar, Narjes; Ghorbannezhad, Fatemeh; Soheili Bidgoli, Nayyereh Sadat; Baran, Talat; Varma, Rajender S.Palladium (Pd) complexes supported on the polymers have been widely used in various organic syntheses endeavors because of their thermal stability, high catalytic activities and recyclability. This article provides contemporary advancements in the deployment of polymer-supported Pd complexes (PSP complexes) in Sonogashira coupling reactions (SCR) of halobenzenes with alkynes. Although most of the reports on SCR are focused on aryl iodides, newer methodologies with supported Pd enable the activation of other aryl halides, especially chlorides, which are discussed in this review.Öğe Recent developments in polymer-supported ruthenium nanoparticles/complexes for oxidation reactions(Elsevier, 2021) Nasrollahzadeh, Mahmoud; Soleimani, Fahimeh; Bidgoli, Nayyereh Sadat Soheili; Nezafat, Zahra; Orooji, Yasin; Baran, TalatPolymers are extensively used as supports for the fabrication of catalysts. They have many advantages such as high thermal stability, ease of modification, high mechanical strength and large surface area. In recent years, the methods for the preparation of metal nanoparticles and complex based catalysts have been developed to a great extent. The presence of supports in the construction of catalysts prevents the accumulation of metal nanoparticles. In this review, polymer-supported ruthenium (Ru) catalysts (in two complex and nano forms) have been covered as significant catalysts for the oxidation of compounds such as types of alcohols, D-glucose, 5-hydroxymethylfurfural, etc. Oxidation of alcohols is of outstanding importance both in industrial and academic research. The solvent, oxygen pressure and temperature are the significant reaction parameters in the process. The advantages and differences related to the reported polymer-supported Ru catalyst systems have been reviewed, while new progresses, for example, a catalyst system for optimal oxidations, have also been outlined.
