86-00-0Relevant academic research and scientific papers
Regioselective mononitration of biphenyl by use of stoichiometric quantities of nitrogen dioxide and molecular oxygen over rare earth cationexchanged β-Zeolite catalysts
Tai, Yan Fang,Dong, Xiong Zi,Xu, Hao Shu,Shi, Chun Jie,Peng, Xin Hua
, p. 9643 - 9653 (2015)
In the presence of molecular oxygen and zeolite La-b with Si/ Al2 = 260, regioselective mononitration of biphenyl with stoichiometric quantities of liquid nitrogen dioxide occurs at 20 °C to yield mononitrobiphenyl, as the main product, in yields up to 82.7 %. The 2-nitrobiphenyl:4-nitrobiphenyl isomer ratio is 0.34. The process is eco-friendly and inexpensive, and the zeolite is easily regenerated by simple work-up to give results similar to those obtained with the fresh catalyst.
Preparation and characterization of new palladium complex immobilized on (chitosan)/PoPD biopolymer and its catalytic application in Suzuki cross-coupling reaction
Seyedi, Neda,Zahedifar, Mahboobeh
, (2021/11/17)
The present work reports the design, synthesis, and characterization of palladium complex immobilized on chitosan/poly(o-phenylenediamine) (CS-PoPD-Pd) for the catalytic application in the Suzuki–Miyaura C-C cross-coupling reaction through a nontoxic, inexpensive, eco-friendly, and practical method. Fourier-transform–infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, X-ray diffraction (XRD), and inductively coupled plasma-optical emission spectrometry (ICP-OES) techniques were used for analyzing the prepared catalyst. Characterization studies showed that CS-PoPD-Pd was successfully synthesized according to our design. CS-PoPD-Pd composite demonstrated high product yield and high turnover number (TON) and turnover frequency (TOF) values with small catalyst loading for the Suzuki–Miyaura C-C cross-coupling reaction under mild reaction conditions. Besides, the synthesized CS-PoPD-Pd composite could be readily recycled and reused for at least five runs without discernible loss of its catalytic activity.
Pd(II) and Ni(II) complexes containing ONNO tetradentate Schiff base ligand: Synthesis, crystal structure, spectral characterization, theoretical studies, and use of PdL as an efficient homogeneous catalyst for Suzuki–Miyaura cross-coupling reaction
Ashfaq, Muhammad,Bahadori, Mehrnaz,Behjatmanesh-Ardakani, Reza,Fallah-Mehrjardi, Mehdi,Kargar, Hadi,Moghadam, Majid,Munawar, Khurram Shahzad,Tahir, Muhammad Nawaz
, (2021/12/27)
Two new palladium(II) and nickel(II) Schiff base complexes are prepared through the reaction of Pd(OAc)2 and Ni(OAc)2·4H2O with a tetradentate ONNO Schiff base, derived by condensing 4,5-dimethyl-1,2-phenylenediamine and 4-methoxysalicylaldehyde. The elemental analysis (CHN) and other spectroscopic techniques such as FT-IR and 1H NMR were used to characterize the synthesized ligand and its corresponding metal complexes. Moreover, the crystal structure of the Pd(II) complex was investigated by the single crystal X-ray diffraction analysis. The diffraction analysis explores a slightly distorted square planar geometry of the PdL complex due to the coordination with deprotonated phenolic O-atoms and N-atoms from azomethine chromophore. The DFT-based theoretical calculations which employed the B3LYP/Def2-TZVP level of theory explore that the theoretical results corresponded to the actual data obtained via spectroscopic characterization.
Photoelectric properties of aromatic triangular tri-palladium complexes and their catalytic applications in the Suzuki-Miyaura coupling reaction
Li, Jia,Li, Xujun,Liu, Xiang,Maestri, Giovanni,Malacria, Max,Wang, Xiaoshuang,Wang, Yanlan,Wu, Lingang
supporting information, p. 11834 - 11842 (2021/09/06)
The photoelectric properties and catalytic activities of substituted triphenylphosphine and sulfur/selenium ligand supported aromatic triangular tri-palladium complexes1-4, abbreviated as [Pd3]+, were investigated. The cyclic voltammogram of [Pd3]+in CH3CN-nBu4NPF6showed a single quasi-reversible wave which was consistent with their robust property and provided preliminary proof for their electron transfer processes in catalysis. With excitation at 267 nm, [Pd3]+exhibited strong ratiometric fluorescence at 550 and 780 nm at a temperature gradient from 77 K to 287 K. These peculiar triangular tri-palladium complexes showed excellent catalytic activities and exclusive reactivity with aryl iodides over the other halogenated aromatics in the Suzuki-Miyaura coupling reaction. The electronic and steric hindrance effects of substituents on the aryl iodides and aryl boronic acids including heteroaromatics like pyridine, pyrazine and thiophenes were explored and most substrates achieved up to 99% of yields. (2-[1,1′-Biphenyl]-2-ylbenzothiazole) which was analogous to the selective cyclooxygenase-2 (COX-2) inhibitors was also synthesized with our tri-palladium catalyst and gave good isolated yield (94%). The study of the catalytic process revealed that the mechanism of the reaction may involve the replacement of the sulphur ligand on [Pd3]+by iodine from aryl iodides, which was beneficial for the matching of C-I bond energy.
Nanocellulose Supported PdNPs as in situ Formed Nano Catalyst for the Suzuki Coupling Reaction in Aqueous Media: A Green Approach and Waste to Wealth
Aabaka, Sreenath Reddy,Mao, Jincheng,Lavanya, Mallu,Venkateswarlu, Katta,Huang, Zhiyu,Mao, Jinhua,Yang, Xiaojiang,Lin, Chong
supporting information, (2021/02/21)
An effective and highly sustainable method has been developed for the Suzuki coupling reaction of aryl halides and phenylboronic acid using in situ generated nacocellulose (NC) supported palladium nanoparticles (Pd@NC NPs) as heterogeneous catalysts in water. The formation of PdNPs was observed in the absence of additional reagents, during the course of the Suzuki reaction from NC and Pd(OAc)2. In situ formed Pd@NC NPs have been systematically characterized using TEM, EDX, XRD and FT-IR techniques. The in situ generated catalyst was separated and studied for its successful reusability up to 11 cycles. The application of aqueous media, use of in situ formed catalyst, mild reaction conditions, absence of volatile organic solvents, broad substrate scope, high product isolated yields are the significant developments of this protocol. The nanocellulose used for this protocol has been generated form the waste cotton cloth and hence it is an example for the waste to wealth and sustainable approach.
NiFe2O4@SiO2@ZrO2/SO42-/Cu/Co nanoparticles: A novel, efficient, magnetically recyclable and bimetallic catalyst for Pd-free Suzuki, Heck and C-N cross-coupling reactions in aqueous media
Alavi G., Seyyedeh Ameneh,Nasseri, Mohammad Ali,Kazemnejadi, Milad,Allahresani, Ali,Hussainzadeh, Mahdi
, p. 7741 - 7757 (2021/05/13)
The novel heterogeneous bimetallic nanoparticles of Cu-Co were synthesized based on magnetic nanoparticles, and the magnetic nanocatalyst was characterized by XRD, FE-SEM, EDX mapping, BET, TEM, HRTEM, FTIR, TGA, and VSM. This catalyst was successfully applied as a recyclable magnetically catalyst in Heck, Suzuki, and C-N cross-coupling reactions with various aryl halides (iodides, bromides, and chlorides as challengeable substrates), with olefins, phenylboronic acid, and amines, respectively. We considered the rise of synergetic effects from the different Lewis acid and Br?nsted acid sites present in the catalyst. The catalyst was synthesized with cheap, available materials and a simple synthesis method. The catalyst can be separated easily using an external magnet. It was recycled for more than ten runs without a sensible loss of its catalytic activity, and no significant leaching of the Cu and Co quantity was observed. The significant benefits of the method are high-level generality, simple operation, and there are no heavy metals and toxic solvents. This is a quick, easy, efficacious and environmentally friendly protocol, and no by-products are formed in the reaction. These features make it an appropriate practical alternative protocol. In comparison with recent works, the other advantage of this catalyst is the synthesis of a wide variety of C-C and C-N bond derivatives (more than 40 derivatives). The other significant advantage is the low temperature of the reaction and the use of the least possible amount of the catalyst (0.003 g). The efficiency was good to excellent and the catalyst selectivity has been high. We aspire that our study inspires more interest to design novel catalysts based on using low-cost metal ions (such as cobalt and copper) in the cross-coupling reactions. This journal is
Pd(II) complexes with ONN pincer ligand: Tailored synthesis, characterization, DFT, and catalytic activity toward the Suzuki-Miyaura reaction
Bagri, Sanjay Singh,Chaurasia, Bhaskar,Gaur, Pratiksha,Mehrotra, Ripul,Raidas, Mohan Lal,Shukla, Satyendra Nath
, (2020/08/25)
A pincer type ONN tridentate Schiff base ligand, 2-(((pyridin-2-yl)methylimino)methyl)-6-methoxyphenol, (L1) synthesized by the condensation of 4-hydroxy-3-methoxy-benzaldehyde and (pyridin-2-yl)methanamine. The ligand L1 and the new Pd(II) heteroleptic complexes of the composition [Pd(L1)(L2)]Cl, where L2 = benzimidazole, imidazole, benzooxazol or pyridine were synthesized and characterized by a set of chemical, spectrometric and spectroscopic analyses. These complexes were named 1 to 4, respectively. The FT-IR and DFT have suggested that ligand is coordinated with metal through azomethine-N and phenolic-O and arranged in square planar fashion around the metal. Correlation coefficients value between 0.995 - 0.993 shows satisfactory agreement in theoretical and experimental 1H-NMR and 13C-NMR. Benzimidazole anchored complex 1 exhibits an excellent catalytic activity. DFT calculated the energy profile diagram of the Suzuki-Miyaura reaction.
Pd-Catalysed Suzuki-Miyaura cross-coupling of aryl chlorides at low catalyst loadings in water for the synthesis of industrially important fungicides
Goetz, Roland,Hashmi, A. Stephen K.,Orecchia, Patrizio,Petkova, Desislava Slavcheva,Rominger, Frank,Schaub, Thomas
supporting information, p. 8169 - 8180 (2021/11/01)
The Suzuki-Miyaura coupling reaction of electron-poor aryl chlorides in the synthesis of crop protection-relevant active ingredients in water is disclosed. Optimisation of the reaction conditions allowed running the reaction with 50 ppm of Pd-catalyst loading without an additional organic solvent in the cross-coupling reaction step in short reaction times. The system was optimised for the initial cross-coupling step of the large scale produced fungicides Boscalid, Fluxapyroxad and Bixafen up to 97% yield. It is also shown that the Suzuki-Miyaura reaction can be easily scaled up to 50 g using a simple product separation and purification using environmentally benign solvents in the work-up. To show the usability of this method, it was additionally applied in the three-step synthesis of the desired active ingredients.
Non-c2-symmetric bis-benzimidazolium salt applied in the synthesis of sterically hindered biaryls
Chen, Yen-Hsin,Hsu, Tung-Yu,Huang, Shu-Jyun,Hung, Pei-Yu,Lee, Dong-Sheng,Lu, Ta-Jung,Wei, Ting-Rong
, (2021/11/27)
A novel non-C2-symmetric bis-benzimidazolium salt derived from (±)-valinol has been prepared by a simple and straightforward process in good yield. The structure of bis-benzimidazolium salt provided a bulky steric group on the ethylene bridge; which facilitates the catalytic efficacy in the C(sp2 )–C(sp2 ) formation. Its catalytic activity in Suzuki–Miyaura cross-coupling reaction of unactivated aryl chlorides has been found to have high efficacy in 1 mol% Pd loading. This protocol demonstrated the potential on the synthesis of sterically hindered biaryls.
Polydopamine-Encapsulated Dendritic Organosilica Nanoparticles as Amphiphilic Platforms for Highly Efficient Heterogeneous Catalysis in Water
Gao, Jing,Guo, Na,Jiang, Yanjun,Liu, Guanhua,Liu, Pengbo,Liu, Yunting,Wang, Zihan,Zhang, Lei
supporting information, p. 1975 - 1982 (2021/06/09)
Aqueous heterogeneous catalysis is a green, sustainable catalytic process that attracts increasing attention, but it often suffers from poor mass transfer, substrate adsorption and catalyst dispersion. Herein, we synthesized a type of amphiphilic core-shell catalysts with a hydrophilic polydopamine (PDA) shell and a hydrophobic dendritic organosilica nanoparticle (DON) core for heterogeneous catalysis in water. The hydrophilic shell allowed the catalyst dispersing well in water, and the hydrophobic core facilitated the absorption of organic reactants. The hierarchical core-shell structure facilitated rational arrangement of the location of catalytic species to match the reaction sequence. The obtained metal, enzyme and metal-enzyme amphiphilic catalysts demonstrated improved stability, selectivity and activity in aqueous reactions, including Pd-catalyzed cross-couplings (Suzuki, Liebeskind-Srogl, Heck and Sonogashira), enzymatic enantioselective reduction, chemoenzymatic cascade synthesis of chiral compounds and chemoenzymatic cascade degradation of organophosphates. The amphiphilic catalysts could be easily in situ recovered, and their high catalytic performance was sustained for five cycles.
