92-67-1Relevant articles and documents
Turning on Catalysis: Construction of Triphenylphosphine Moieties into Porous Frameworks
Chen, Fang,Wang, Sai,Sun, Qi,Xiao, Feng-Shou
, p. 3285 - 3289 (2020)
In this work, we present an effective strategy to enhance the reactivity and durability of molecular organometallic catalysts by constructing into porous frameworks, as demonstrated by triphenylphosphine (PPh3). Such PPh3 moieties accessible via the porous structures could be partially metalated by Pd species to generate a highly efficient and recyclable heterogeneous catalyst for the Suzuki coupling of aryl chlorides. Site isolation in the rigid framework stabilizes the catalytically active monophosphine-ligated complex against deactivation into less active assemblies of bisphosphine-Pd. Meanwhile, the densely populated free ligands inhibit the decomposition of catalytically active sites thereby highlighting the beneficial effects of such a platform. Thus, the tunability of porous polymer synthesis gives great promise to impart numerous organometallic catalysts constituted by readily available ligands with unique reactivity, which are not trivially achievable with traditional systems.
Template-less synthesis of polymer hollow spheres: An efficient catalyst for Suzuki coupling reaction
Choudhary, Meenakshi,Islam, Rafique Ul,Witcomb, Michael J.,Phali, Motlatsi,Mallick, Kaushik
, p. 523 - 528 (2013)
We report here a method for the preparation of polymer hollow spheres in which 3-aminoquinoline (3-AQ) and palladium acetate were used as precursors. During the reaction 3-AQ was oxidized and formed poly(3-AQ). IR and Raman spectra provided information on the chemical structure of the polymer. The oxidation state of palladium was confirmed by X-ray photoelectron spectroscopic analysis. Transmission and scanning electron microscopy were used to determine the size and morphology of the polymer. The palladium-poly(3-AQ) supramolecular system was used as an effective catalyst for the Suzuki coupling reaction of aryl halides in the absence of a phosphine ligand. Copyright
Suzuki cross-coupling of aryl halides with phenylboronic acid catalysed by an amidoxime fibres-nickel(0) complex
Wu, Zhi-Chuan,Lu, Ye-Neng,Ren, Yi-Ming,Chen, Zhi-Ming,Tao, Ting-Xian
, p. 451 - 454 (2013)
Amidoxime fibres-nickel(0) complexes [Ni(0)-AOFs] were synthesised by combining a Ni2+-solution with amidoxime fibres and reduced by NaH 2PO2. The Ni(0)-AOFs are inexpensive phosphine-free recyclable heterogeneous catalysts for the Suzuki coupling reaction of aryl halides with phenylboronic acid to provide the corresponding biphenyls in high yields. The heterogeneous catalyst can be readily recovered by simple filtration and reused several times without significant loss of activity.
In situ biosynthesis of palladium nanoparticles on Artemisia abrotanum extract-modified graphene oxide and its catalytic activity for Suzuki coupling reactions
Salehi, Mirmehdi Hashemi,Yousefi, Mohammad,Hekmati, Malak,Balali, Ebrahim
, p. 132 - 137 (2019)
We progressed the catalytic activity of Pd NPs coated on Artemisia abrotanum extract-modified graphene (Pd NPs/RGO) for the Suzuki coupling reactions. Pd NPs/RGO nanocatalyst was fabricated via modifying the surface of graphene oxide (GO) with A. abrotanum extract as a reducing and stabilizing agent with no addition of any toxic agent to in situ reduction and immobilizing Pd nanoparticles. Sundry methods like FTIR, UV–Vis, ICP-AES, XRD, FE-SEM, WDX, TEM and EDX have been used for explaining the structure and morphology of the Pd NPs/RGO nanocatalyst. The outcomes indicate that the Pd (0) nanoparticles are completely spread on the functionalized GO surface. Pd NPs/RGO showed excellent catalytic performance as a recyclable nanocatalyst in Suzuki-Miyaura reactions with high yields. Moreover, the recycled nanocatalyst showed no considerable loss in its activity.
Control of the coordination structure of organometallic palladium complexes in an apo-ferritin cage
Abe, Satoshi,Niemeyer, Jochen,Abe, Mizue,Takezawa, Yusuke,Ueno, Takafumi,Hikage, Tatsuo,Erker, Gerhard,Watanabe, Yoshihito
, p. 10512 - 10514 (2008)
We report the preparation of organometallic Pd(allyl) dinuclear complexes in protein cages of apo-Fr by reactions with [Pd(allyl)Cl]2 (allyl = η3-C3H5). One of the dinuclear complexes is converted to a trinuclear complex by replacing a Pd-coordinated His residue to an Ala residue. These results suggest that multinuclear metal complexes with various coordination structures could be prepared by the deletion or introduction of His, Cys, and Glu at appropriate positions on protein surface. Copyright
Open-vessel microwave-promoted Suzuki reactions using low levels of palladium catalyst: Optimization and scale-up
Leadbeater, Nicholas E.,Williams, Victoria A.,Barnard, Thomas M.,Collins Jr., Michael J.
, p. 833 - 837 (2006)
Representative Suzuki couplings in water using low catalyst concentrations in conjunction with microwave heating have been transferred from sealed-vessel to open-vessel reaction conditions. They have then been scaled-up to the mole scale using a dedicated multimode microwave apparatus. The reactions are complete within 20 min of heating at reflux.
Sustainable catalysis using magnetic chicken feathers decorated with Pd(0) for Suzuki-cross coupling reaction
Padma Latha,Bhatt, Mukesh,Jain, Suman L.
, p. 5718 - 5722 (2015)
Magnetic nanoparticles (Fe3O4) coated with chicken feather (CF) were synthesized and subsequently grafted with palladium nanoparticles (Pd NPs) using in situ preparation approach. The synthesized catalyst showed excellent activity for Suzuki cross coupling reaction between aryl halides and phenylboronic acid. After completion of the reaction, the catalyst could conveniently be separated via magnetic separation. More importantly, the presence of amino and carboxyl groups on the surface due to chicken feather, provided sufficient binding sites for Pd NPs, and therefore make the synthesized material highly stable. No leaching was observed during the reaction as ascertained by ICP-AES analysis. Furthermore, the catalytic activity of this supported catalyst did not show any significant loss after being used for at least six times.
An environment-friendly dip-catalyst with xylan-based catalytic paper coatings
He, Mengyun,Song, Tao,Qi, Haisong,Xiang, Zhouyang
, (2021/10/12)
Replacing catalyst supports with sustainable and degradable materials is an urgent task. Xylan is a type of abundant natural polymers with potential applications in dispersing, anchoring, and coating materials, but its material values have always been underestimated. In this study, polyethyleneimine modified dialdehyde xylan (DAX-PEI) was used as a dispersing and anchoring agent to bind Pd nanoparticles onto paper surface to produce a DAX-PEI-Pd coated paper, which was used to catalyze Suzuki-Miyaura reactions. The catalytic coated paper exhibited a good catalytic activity with a yield of 91% and a high turnover frequency (TOF) of 3300 h?1. Besides, it showed an excellent recyclability with the same catalytic coated paper being used 15 times and still having a yield of nearly 90%. This environment-friendly catalytic coated paper owns its great prospect in organic synthesis.
Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 1618 - 1629 (2021/01/25)
Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
NaI/PPh3-Mediated Photochemical Reduction and Amination of Nitroarenes
Qu, Zhonghua,Chen, Xing,Zhong, Shuai,Deng, Guo-Jun,Huang, Huawen
supporting information, p. 5349 - 5353 (2021/07/21)
A mild transition-metal- and photosensitizer-free photoredox system based on the combination of NaI and PPh3 was found to enable highly selective reduction of nitroarenes. This protocol tolerates a broad range of reducible functional groups such as halogen (Cl, Br, and even I), aldehyde, ketone, carboxyl, and cyano. Moreover, the photoredox catalysis with NaI and stoichiometric PPh3 provides also an alternative entry to Cadogan-type reductive amination when o-nitrobiarenes were used.