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Aghajani S, Mohammadikish M. A stable hybrid catalyst (POM-PPPh 3/L/Ni) for the reduction of toxic nitroarene compounds in water. Dalton Trans 2024; 53:10644-10654. [PMID: 38860318 DOI: 10.1039/d4dt00909f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Reduction of nitroarenes to aminoarenes using novel and selective catalysts is an important and desirable approach in green chemistry. In this work, a new heterogeneous nanocatalyst, POM-PPPh3/L/Ni, was designed and prepared via functionalizing a Keggin-type polyoxometalate (H3PMo12O40) with (3-bromopropyl)triphenylphosphonium bromide (BPPPh3Br) through strong electrostatic interactions to prepare [PMo12O40][PPPh3]3 (denoted as POM-PPPh3). The obtained compound was modified via nucleophilic attack of the nitrogen donor of a multidentate Schiff base ligand (L) on its propyl chain to produce [PMo12O40][PPPh3/L]2 (denoted as POM-PPPh3/L), which was finally metallated with nickel cations to achieve [PMo12O40][PPPh3/L/Ni]2 (denoted as POM-PPPh3/L/Ni). After full characterization of the prepared material with various physicochemical methods, its catalytic behavior was investigated in the catalytic nitroarene reduction. The influence of various factors on catalytic conversion and selectivity was considered. The synthesized nanocatalyst showed excellent performance in the reduction of nitroarenes in aqueous media in the presence of NaBH4 as a reducing agent. Mild reaction conditions and a short reaction time (10 min) are the prominent features of this new nanocatalyst. In addition, the catalyst was recovered and reused for up to four cycles of catalytic reduction without any significant loss of conversion.
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Affiliation(s)
- Shima Aghajani
- Department of Inorganic Chemistry, Faculty of Chemistry, Kharazmi University, 15719-14911, Tehran, Iran.
| | - Maryam Mohammadikish
- Department of Inorganic Chemistry, Faculty of Chemistry, Kharazmi University, 15719-14911, Tehran, Iran.
- Research Institute of Green Chemistry, Kharazmi University, Tehran, Iran
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2
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Gong Y, Liu T, Yang M, Tian A, Ying J. A series of viologen/POM materials with discoloration properties under the stimulation of X-ray, UV, electricity, and organic amines. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 313:124154. [PMID: 38492466 DOI: 10.1016/j.saa.2024.124154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/10/2024] [Accepted: 03/11/2024] [Indexed: 03/18/2024]
Abstract
At present, viologen-based compounds can undergo reversible chemical/physical changes under external stimuli such as light and electricity. This makes these compounds have potential applications in smart windows, displays, and sensors. In order to obtain such materials, three viologen-POM inorganic-organic hybrid compounds have been successfully synthesized by a hydrothermal method, namely {[Cu2(cybpy)8(α-P2W18O62)2}·18H2O (1), (Hbpy)·(cybpy)·[H4(α-P2W18O62)]}·32H2O (2) and {(Hcybpy)2(β-Mo8O26)}·2H2O (3) (cybpy·Br = 1-cyclobutylmethyl-[4,4']bipyridinyl-1-ium bromide, bpy = 4,4'-bipyridine). Three compounds exhibit good discoloration behaviors under various external stimuli, especially under the stimulation of X-ray, UV, electricity, and organic amines. In addition, in order to promote the compounds in the actual production of more applications, they were doped into the polymer matrix to construct hybrid films, which not only have the same response to external stimulation but also increase the repeatability of the photochromic process. Moreover, 1-3 powder samples in ethanol solution were ultrasonic treated and deposited on filter paper, which can be successfully used in erasable inkless printing.
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Affiliation(s)
- Yuan Gong
- Department of Chemistry, Bohai University, Jinzhou 121013, PR China
| | - Tao Liu
- Department of Chemistry, Bohai University, Jinzhou 121013, PR China
| | - Mengle Yang
- Department of Chemistry, Bohai University, Jinzhou 121013, PR China.
| | - Aixiang Tian
- Department of Chemistry, Bohai University, Jinzhou 121013, PR China
| | - Jun Ying
- Department of Chemistry, Bohai University, Jinzhou 121013, PR China.
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3
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Habeeb Naser I, Thoulfikar A. Alamir H, Al-Shukarji AH, Ahmed BA, Qassem TA, Kamal M, Almeleebia TM, Alwaily ER, Hasan Kadhum E, Alawadi A, Alsalamy A. Choline chloride/urea as a green and efficient deep eutectic solvent in three-component and four-component synthesis of novel pyrazole and pyrano[2,3-c] pyrazole derivatives with antibacterial and antifungal activity. Front Chem 2024; 12:1342784. [PMID: 38435668 PMCID: PMC10904593 DOI: 10.3389/fchem.2024.1342784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
In this study, choline chloride/urea was used as a green deep eutectic solvent in the three-component reaction of hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrazole derivatives, and in the four-component reaction of methyl/ethyl acetoacetate, hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrano[2,3-c]pyrazole derivatives. Elemental analysis, 1H, and 13C NMR spectroscopy were used to confirm the structure of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives. The antimicrobial effects of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives were investigated. In antimicrobial tests, instructions from clinical and laboratory standards institutes were used. Antimicrobial study was done on pathogenic gram-positive and gram-negative species, and specialized aquatic strains and fungal species. Using choline chloride/urea, novel pyrazole derivatives and pyrano[2,3-c]pyrazole derivatives were synthesized, and other derivatives were synthesized with higher efficiency in less time than some previously reported methods. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) obtained for derivatives were higher than some antibiotic drugs. Synthesis and reports of new derivatives of pyrazole and pyrano[2,3-c]pyrazole, and investigation and reports of their antimicrobial properties on gram-positive, gram-negative, and specialized aquatic and fungal species are among the novel and important findings of this study.
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Affiliation(s)
- Israa Habeeb Naser
- Medical Laboratories Techniques Department, Al-Mustaqbal University, Hillah, Iraq
| | | | - Ali Hisham Al-Shukarji
- Department of Medical Laboratories Technology, Al-Manara College for Medical Sciences, Maysan, Iraq
| | - Batool Ali Ahmed
- Department of Medical Engineering, Al-Nisour University College, Baghdad, Iraq
| | - Talal Aziz Qassem
- Department of Medical Laboratory Technics, Al-Noor University College, Nineveh, Iraq
| | - Maher Kamal
- Department of Dentistry, Al-Hadi University College, Baghdad, Iraq
| | - Tahani M. Almeleebia
- Department of Clinical Pharmacy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Enas R. Alwaily
- Microbiology Research Group, College of Pharmacy, Al-Ayen University, Thi-Qar, Iraq
| | | | - Ahmed Alawadi
- College of Technical Engineering, The Islamic University, Najaf, Iraq
- College of Technical Engineering, The Islamic University of Al Diwaniyah, Al Diwaniyah, Iraq
- College of Technical Engineering, The Islamic University of Babylon, Babylon, Iraq
| | - Ali Alsalamy
- College of Technical Engineering, Imam Ja’afar Al‐Sadiq University, Al‐Muthanna, Iraq
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4
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Lun HJ, Zhang ZM, Sun YH, Wang MM, Cai JJ, Liang XY, Li YM, Bai Y. N-N-Bridged Polynuclear POM-Based Coordination Polymers Based on a V-Type Ligand: Proton Conduction and Magnetism. Inorg Chem 2023; 62:17093-17101. [PMID: 37800965 DOI: 10.1021/acs.inorgchem.3c01606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
The construction of polyoxometalate (POM)-based coordination polymers, in the presence of a nitrogen heterocyclic ligand, is intriguing due to the potential for obtaining diverse structures. These structures exhibit extensive application possibilities in the fields of proton conductivity and magnetism. Herein, four new POM-based polynuclear coordination polymers with the formulas of {[Fe2(btb)3(H2O)2(SiW12O40)]·3H2O}n (1), {[Cd2(btb)2(H2O)6(HPMoVI10MoV2O40)]·2H2O}n (2), {[Co3(OH)2(btb)2(H2O)5(HPMoVI10MoV2O40)]·7H2O}n (3), and {[Cu3(OH)(btb)2(H2O)(HP2Mo5O23)]·6H2O}n (4) have been prepared using the V-type 1,3-bis(4H-1,2,4-triazole-4-yl)benzene (btb) ligand. Compounds 1 and 2 feature similar two-dimensional (2D) structures, derived from the binuclear Fe2N6 and Cd2N4 subunits connected by tridentate btb ligands. Meanwhile, in compound 3, hexanuclear Co6(OH)4 units are bound by quadridentate btb ligands forming a 2D layer with the same 4-c sql topology simplification as compounds 1 and 2. In compound 1, Keggin-type polyoxoanions are monodentate-coordinated to metal ions and suspended on the 2D structure, while, in compounds 2 and 3, they act as discrete counterions residing in the interstitial spaces between two adjacent layers, thereby extending the 2D structures into 3D structures through hydrogen bonding interactions. In compound 4, trinuclear Cu3(OH) subunits are further constructed into a 3D framework through cooperation with four tridentate and quadridentate btb ligands as well as Strandberg-type anions. Furthermore, the proton conduction of the four compounds has been investigated. They display high proton conductivities at 358 K and 98% RH with powdered samples, which are 1.26 × 10-3, 1.24 × 10-3, 3.24 × 10-4, and 2.57 × 10-4 S cm-1, respectively. Interestingly, by mixing with Nafion, the composite membranes of compounds 2 and 4 exhibit enhanced proton conductivities, measuring at 4.87 × 10-2 and 1.28 × 10-2 S cm-1, respectively, at 358 K and 98% RH, which suggests excellent potential for applications. In addition, compounds 1, 3, and 4 display antiferromagnetic behaviors due to similar magnetic interactions. This work can provide research insights into the assembly of 2D POM-based coordination polymers with nitrogen heterocyclic ligands and Keggin-type POMs and further promote their research progress in proton conduction.
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Affiliation(s)
- Hui-Jie Lun
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Zhi-Min Zhang
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Ya-Hao Sun
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Meng-Meng Wang
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Jun-Jie Cai
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Xin-Yu Liang
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Ya-Min Li
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Yan Bai
- Henan Key Laboratory of Polyoxometalate, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
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5
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Yekke-Ghasemi Z, Heravi MM, Malmir M, Mirzaei M. Efficient oxidation of sulfides to sulfoxides catalyzed by heterogeneous Zr-containing polyoxometalate grafted on graphene oxide. Sci Rep 2023; 13:16752. [PMID: 37798421 PMCID: PMC10556038 DOI: 10.1038/s41598-023-43985-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 10/01/2023] [Indexed: 10/07/2023] Open
Abstract
In this study, a tri-component composite named Zr/SiW12/GO was meticulously prepared through an ultrasonic-assisted method. This composite incorporates zirconium nanoparticles (Lewis acid), a negatively charged Keggin type polyoxometalate, and graphene oxide, and serves as a remarkable heterogeneous catalyst. The Keggin component plays multiple roles as reducing, encapsulating, and bridging agents, resulting in a cooperative effect among the three components that significantly enhances the catalytic activity. The catalytic performance of Zr/SiW12/GO was thoroughly investigated in the oxidation of sulfides to sulfoxides under mild conditions, employing H2O2 as the oxidant. Remarkably, this composite exhibited exceptional stability and could be effortlessly recovered and reused up to four times without any noticeable loss in its catalytic activity.
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Affiliation(s)
- Zahra Yekke-Ghasemi
- Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Majid M Heravi
- Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran.
| | - Masoume Malmir
- Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Masoud Mirzaei
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, 9177948974, Iran.
- Khorasan Science and Technology Park (KSTP), 12Th Km of Mashhad-Quchan Road, MashhadKhorasan Razavi, 9185173911, Iran.
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Guo L, He L, Zhuang Q, Li B, Wang C, Lv Y, Chu J, Song YF. Recent Advances in Confining Polyoxometalates and the Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2207315. [PMID: 36929209 DOI: 10.1002/smll.202207315] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/24/2023] [Indexed: 06/15/2023]
Abstract
Polyoxometalates (POMs) are widely used in catalysis, energy storage, biomedicine, and other research fields due to their unique acidity, photothermal, and redox features. However, the leaching and agglomeration problems of POMs greatly limit their practical applications. Confining POMs in a host material is an efficient tool to address the above-mentioned issues. POM@host materials have received extensive attention in recent years. They not only inherent characteristics of POMs and host, but also play a significant synergistic effect from each component. This review focuses on the recent advances in the development and applications of POM@host materials. Different types of host materials are elaborated in detail, including tubular, layered, and porous materials. Variations in the structures and properties of POMs and hosts before and after confinement are highlighted as well. In addition, an overview of applications for the representative POM@host materials in electrochemical, catalytic, and biological fields is provided. Finally, the challenges and future perspectives of POM@host composites are discussed.
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Affiliation(s)
- Lin Guo
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Lei He
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Qinghe Zhuang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Bole Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Cuifeng Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yanfei Lv
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Jinfeng Chu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yu-Fei Song
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
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7
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Kumar A, Kumar Das D, Kishore Sharma R, Selvaraj M, A. Assiri M, Ajmal S, Zhang G, Gupta RK, Yasin G. Study of Oxygen Reduction Reaction on Binuclear-Phthalocyanine with Fe-Fe, Co-Co, and Fe-Co Dual-Atom-Active Sites using Density Functional Theory. J IND ENG CHEM 2023. [DOI: 10.1016/j.jiec.2023.03.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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8
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Osuka Y, Ii K, Tsuchiya K, Nemoto M, Sahoo YV, Takahashi K, Tanaka M. Molecular Speciation of Isopolyoxomolybdates and Isopolyoxotungstates with Silicic Acid in Aqueous Solution Using ESI–MS. J SOLUTION CHEM 2023. [DOI: 10.1007/s10953-023-01255-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
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9
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Hybrid proton-containing decavanadate-organic crystal: synthesis, structure and enhancement of proton-conducting performance. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2023. [DOI: 10.1007/s13738-023-02759-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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10
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Sisakhti ZN, Malmir M, Bisafar MB, Heravi MM, Hosseinnejad T. Direction of theoretical and experimental investigation into the mechanism of n-HA/Si-PA-SC@Ag as a bio-based heterogeneous catalyst in the reduction reactions. Sci Rep 2022; 12:21964. [PMID: 36535991 PMCID: PMC9763413 DOI: 10.1038/s41598-022-26200-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
In the present study, a natural-based heterogeneous catalyst is synthesized. For this purpose, nano-hydroxyapatite (n-HA) is prepared, silica-modified and functionalized with phthalimide. Finally, Ag2+ was immobilized onto n-HA/Si-PA-SC and reduced to Ag nanoparticles by Bellis perennis flowers extract. n-HA/Si-PA-SC@Ag characterized by TGA, FTIR, SEM/EDX, XRD, TEM, BET and ICP-AES techniques. Moreover, metal-ligand interactions in n-HA/Si-PA-SC@Ag complex models were assessed to make a quantitative representation for the immobilization behavior of Ag NPs on the surface of n-HA/Si-PA-SC through quantum chemistry computations. Furthermore, the performance of n-HA/Si-PA-SC@Ag was studied in the nitroarene, methylene blue and congo red reductions. Finally, the recyclability study as well as Ag-leaching verified that, n-HA/Si-PA-SC@Ag was stable and reused-up to four times without losing its activity.
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Affiliation(s)
- Zohreh Nouripour Sisakhti
- grid.411354.60000 0001 0097 6984Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Masoume Malmir
- grid.411354.60000 0001 0097 6984Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Masoumeh Bagheri Bisafar
- grid.411354.60000 0001 0097 6984Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Majid M. Heravi
- grid.411354.60000 0001 0097 6984Department of Organic Chemistry, Faculty of Chemistry, Alzahra University, Tehran, Iran
| | - Tayebeh Hosseinnejad
- grid.411354.60000 0001 0097 6984Department of Physical Chemistry and Nano, Faculty of Chemistry, Alzahra University, Tehran, Iran
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Karrabi M, Malmir M, Shafiei toran poshti E, Heravi MM, Hosseinnejad T. A theoretical and experimental study on ecofriendly one-pot synthesis of pyrazolopyranopyrimidines catalysed by CuO functionalized montmorillonite. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.110367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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12
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Malmir M, Heravi MM, Yekke-Ghasemi Z, Saberi S, Mirzaei M. Fabrication of Heterogeneous Zr-containing Polyoxometalate as an Efficient Catalyst for the Synthesis of a Broad Range of 1,5-Benzodiazepine Derivatives. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.134631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Cu2O NPs immobilized on Montmorilonite-K10 decorated by acidic-ionic liquid: An environmentally friendly, heterogeneous and recyclable catalyst for the synthesis of benzopyranopyrimidines. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.109813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Lanthanoid-containing polyoxometalate nanocatalysts in the synthesis of bioactive isatin-based compounds. Sci Rep 2022; 12:12004. [PMID: 35835941 PMCID: PMC9283471 DOI: 10.1038/s41598-022-16384-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 07/08/2022] [Indexed: 11/10/2022] Open
Abstract
Lanthanoid-containing polyoxometalates (Ln-POMs) have been developed as effective and robust catalysts due to their Lewis acid–base active sites including the oxygen-enriched surfaces of POM and the unique 4f. electron configuration of Ln. As an extension of our interest in Ln-POMs, a series of as-synthesized nanocatalysts K15[Ln(BW11O39)2] (Ln-B2W22, Ln = La, Ce, Nd, Sm, Gd, and Er) synthesized and fully characterized using different techniques. The Ln3+ ion with a big ionic radius was chosen as the Lewis acid center which is sandwiched by two mono-lacunary Keggin [BW11O39]9− units to form Ln-containing sandwiched type cluster. Consequently, the catalytic activity of nanocatalysts with different Ln was examined in the synthesis of bioactive isatin derivatives and compared under the same optimized reaction conditions in terms of yields of obtained products, indicating the superiority of the nano-Gd-B2W22 in the aforementioned simple one-pot reaction. The effects of different dosages of nanocatalyst, type of solvent, reaction time, and reaction temperature in this catalytic system were investigated and the best results were obtained in the presence of 10 mol% of nano-Gd-B2W22 in water for 12 min at the reflux condition.
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15
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Incorporating heterogeneous lacunary Keggin anions as efficient catalysts for solvent-free cyanosilylation of aldehydes and ketones. Sci Rep 2022; 12:11573. [PMID: 35799059 PMCID: PMC9262904 DOI: 10.1038/s41598-022-15831-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/29/2022] [Indexed: 12/03/2022] Open
Abstract
Polyoxometalates (POMs) as efficient catalysts can be used a wide range of chemical transformations due to their tunable Brønsted/Lewis-acidity and redox properties. Herein, we reported two hybrid and heterogeneous lacunary Keggin catalysts: (TBA)7[PW11O39] (TBA-PW11) and (TBA)8[SiW11O39]·4H2O (TBA-SiW11) (TBA+: tetrabutylammonium) in which [XW11O39]n− anions were coated by TBA+ cations. In this form, TBA+ can easily trap reactants on the surface of the catalysts and increase the catalytic reaction. Therefore, the catalytic performance of both POMs was tested in cyanosilylation of numerous compounds bearing-carbonyl group and trimethylsilyl cyanide under solvent-free conditions. TBA-PW11 is more effective than TBA-SiW11, conceivably due to the higher Lewis acidity of the P than the Si center and to the higher accessibility of the metal centers in the framework structure. Noteworthy, the recyclability and heterogeneity of both POMs catalysts were also examined, and the results confirmed that they remain active at least after three recycling procedures.
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