Xn:Harmful;86-26-0Relevant articles and documents
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.
'Awaken' aryl sulfonyl fluoride: a new partner in the Suzuki-Miyaura coupling reaction
Ding, Chengrong,Guan, Chenfei,Miao, Huihui,Zhang, Guofu,Zhao, Yiyong
, p. 3560 - 3564 (2022/03/07)
An example of the activation of the -SO2F group, which is traditionally considered a stable group even in the presence of a transition metal, is described using a novel partner in the Suzuki-Miyaura coupling reaction catalyzed by Pd(OAc)2 and Ruphos as ligands. The products showed good to outstanding yields and broad functional group compatibility under optimal conditions. The sequential synthesis of non-symmetric terphenyls and the gram grade process highlight the approach's synthetic utility. DFT calculations have shown that Pd0 prefers to insert between C-S bonds rather than S-F bonds. This journal is
Nickel-Catalyzed Direct Cross-Coupling of Aryl Sulfonium Salt with Aryl Bromide
Chu, Xue-Qiang,Liu, Xiang,Ma, Na-Na,Rao, Weidong,Ren, Jing-Ao,Shen, Zhi-Liang
supporting information, (2022/03/27)
The direct cross-couplings of aryl sulfonium salts with aryl halides could be achieved by using nickel as a reaction catalyst. The reactions proceeded efficiently via C-S bond activation in the presence of magnesium turnings and lithium chloride in THF at ambient temperature to afford the corresponding biaryls in moderate to good yields, potentially serving as an attractive alternative to conventional cross-coupling reactions employing preprepared organometallic reagents.
Aromatization as the driving force for single electron transfer towards C-C cross-coupling reactions
Adhikari, Debashis,Dey, Dhananjay,Kundu, Abhishek,Pal, Subhankar,Roy, Monojit
, p. 1934 - 1940 (2022/04/07)
There is a strong current interest in C-H functionalization reactions under metal-free conditions. We report herein the deprotonated form of dihydrophenazine (DPh) as a potent initiator under photochemical conditions that can efficiently generate aryl radicals via single electron transfer (SET). The driving force for such electron transfer is the gain in aromaticity for the initiator molecule. Using this methodology, a series of arenes and heteroarenes have been cross-coupled with aryls at room temperature. Photochemical activation of DPh anions and the subsequent electron transfer to substrate aryldiazonium salts have been proved by Stern-Volmer kinetic analysis. Detailed mechanistic studies including interception of important reaction intermediates prove the aromaticity-driven SET as the key step to generate aryl radicals towards radical-promoted cross-coupling reactions.
Pd(OAc)2-biuret: A highly efficient, low cost and phosphine-free catalyst system for biaryl synthesis under aerobic conditions at room temperature
Saikia, Bishwajit
, (2021/05/10)
A highly efficient, less expensive and phosphine-free protocol for the Suzuki-Miyaura cross-coupling reactions of aryl halides and aryl boronic acids in iPrOH-H2O solvent under aerobic conditions has been developed. The results demonstrate that the biuret played a crucial role and making this protocol highly efficient. The Pd(OAc)2-biuret system exhibited superb catalytic activity towards the Suzuki-Miyaura cross-coupling reaction of a wide range of aryl halides with aryl boronic acids at room temperature, giving high yields even under very low catalytic loading. This system offers an attractive alternative to the existing protocols since the reaction proceeds in green solvent at room temperature with working simplicity, shorter reaction time, cost-effectiveness and provides the desired products in high yields. The effect of solvent, base as well as catalyst loading on the cross-coupling reaction of aryl halide with arylboronic acid is also described.
Photoelectric properties of aromatic triangular tri-palladium complexes and their catalytic applications in the Suzuki-Miyaura coupling reaction
Li, Xujun,Li, Jia,Wang, Xiaoshuang,Wu, Lingang,Wang, Yanlan,Maestri, Giovanni,Malacria, Max,Liu, Xiang
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.
Hexagonal Boron Nitride Supported N-Heterocyclic Carbene-Palladium(II): A New, Efficient and Recyclable Heterogeneous Catalyst for Suzuki–Miyaura Cross-Coupling Reaction
Antony, Arnet Maria,Kandathil, Vishal,Kempasiddaiah, Manjunatha,Sasidhar,Patil, Shivaputra A.,Patil, Siddappa A.
, p. 1293 - 1308 (2020/10/06)
Abstract: In this study, a new stable and powerful hexagonal boron nitride supported N-heterocyclic carbene-palladium(II) complex (h-BN@NHC-Pd) heterogeneous catalyst was designed and synthesized. The structure of the h-BN@NHC-Pd heterogeneous catalyst was characterized by various techniques such as Fourier transform infrared spectra (FT-IR), ultraviolet–visible spectroscopy (UV–Visible), inductively coupled plasma-optical emission spectroscopy (ICP-OES), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller surface area analysis (BET). Then catalytic activity of h-BN@NHC-Pd heterogeneous catalyst was studied in the Suzuki–Miyaura cross-coupling reactions between aryl halides and arylboronic acids in aqueous medium at room temperature. The effects of varying solvents, bases, temperature, time and catalytic ratios on the performance of the Suzuki–Miyaura cross-coupling reaction were investigated. Moreover, h-BN@NHC-Pd heterogeneous catalyst could be easily recovered through simple filtration or centrifugation method and could be reused five times without significant loss of its catalytic efficiency. Furthermore, stability of the h-BN@NHC-Pd heterogeneous catalyst after recycling was confirmed through FESEM and FT-IR techniques. The h-BN@NHC-Pd heterogeneous catalyst shows remarkable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easily separable and high stability without leaching. Graphic Abstract: A new stable and powerful hexagonal boron nitride supported N-heterocyclic carbene-palladium(II) complex (h-BN@NHC-Pd) heterogeneous catalyst was designed, synthesized, characterized and catalytic activity was studied in the Suzuki–Miyaura cross-coupling reactions. [Figure not available: see fulltext.]
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.
Synthesis, characterization and catalytic application of Bi2S3 microspheres for Suzuki-Miyaura cross-coupling reaction and chemoselective ring opening of epoxides
Ghorbani-Choghamarani, Arash,Taherinia, Zahra
, (2020/11/20)
Bismuth sulfide (Bi2S3) prepared using L-cysteine, which served as both the sulfur source and the directing molecule for the formation of Bi2S3 as heterogeneous catalyst through solvothermal method. The prepared catalyst was examined by various techniques such as XRD, BET, FE-SEM, TEM, and TGA analysis. The results and analysis revealed that bismuth microspheres have better catalytic behavior for the preparation of biphenyl in water as a greenest solvent and for the ring opening of epoxides by nucleophiles including amines, alcohol, and thiol compared to pure Bi(NO3)3. 3H2O under solvent-free condition. Moreover, the novel catalyst could be recovered and reusedat least four times without loss of its catalytic activity.
Preparation of magnetic chitosan-supported palladium-5-amino-1H-tetrazole complex as a magnetically recyclable catalyst for Suzuki-Miyaura coupling reaction in green media
Bakhshali-Dehkordi, Raziyeh,Kamali, Taghi A.,Nasrollahzadeh, Mahmoud,Orooji, Yasin,Shokouhimehr, Mohammadreza
, (2021/07/13)
The utilization of various tetrazoles as efficient ligands is a promising method for the functionalization of tetrazole-based heterogeneous catalysts. Their combination with magnetic species and natural supports exposes huge opportunities for the practical applications of heterogeneous catalysts. In this study, a green and novel strategy is applied to synthesize Fe3O4 magnetic nanoparticles (MNPs) incorporated with chitosan (CS) and 5-amino-1H-tetrazole with a long tail ((3-chloropropyl)trimethoxysilane) to immobilize palladium catalyst designated as Fe3O4–CS@tet-Pd(II). The prepared Fe3O4–CS@tet-Pd(II) was used as an efficient and magnetically recyclable catalyst for the Suzuki-Miyaura cross-coupling reaction (SMCR) using a mixture of EtOH/H2O as green media under aerobic conditions. All the expected products were obtained in high yields, indicating the high efficiency of this catalyst for the preparation of various biaryls by SMCR. Various latest techniques were used to characterize Fe3O4–CS@tet-Pd(II), e.g., Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS) elemental mapping, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning TEM (STEM), high resolution TEM (HR-TEM), vibrating sample magnetometer (VSM), fast Fourier transform (FFT), thermogravimetric analysis (TGA), etc. This study presents a unique example of 5-amino-1H-tetrazole grafted on Fe3O4–CS, which can easily be separated using an external magnet and reused five times without significant decrease of catalytic activity. In addition, the introduced method has significant advantages such as the utilization of natural and inexpensive materials, easy work-up, high yields of products, and high catalytic activity.
