65198-02-9Relevant academic research and scientific papers
Pd salen complex@CPGO as a convenient, effective heterogeneous catalyst for Suzuki–Miyaura and Heck–Mizoroki cross-coupling reactions
Ghabdian, Mahdieh,Nasseri, Mohammad Ali,Allahresani, Ali,Motavallizadehkakhky, Alireza
, p. 1713 - 1728 (2018/05/25)
A Pd(II) Schiff base complex supported on graphene oxide nanosheets (Pd(II) salen@CPGO) has been synthesized and characterized by FT-IR, ICP-AES, XRD, SEM/EDX and TEM. The synthesized nanocatalyst has been found to be an efficient heterogeneous catalyst for Suzuki–Miyaura and Heck–Mizoroki coupling reactions. Pd(II) salen@CPGO could be separated and recovered easily from the reaction mixture and recycled several times without a discernible decrease in its catalytic activity. The construction of a solid sheet-supported Pd catalyst would be expected to be a promising system to perform heterogeneous catalytic reactions.
Triazine-hyperbranched polymer-modified magnetic nanoparticles-supported nano-cobalt for C–C cross-coupling reactions
Hajipour, Abdol R.,Sadeghi, Shaghayegh
, p. 3219 - 3233 (2021/08/06)
Design of hyperbranched polymers (HBPs) and crafting them in catalytic systems especially in organic chemistry are a relatively unexplored domain. This paper reports the utilization of triazine-hyperbranched polymer (THBP)-coated magnetic chitosan nanoparticles (MCs) as stabilizing matrix for cobalt nanoparticles. Cobalt nanoparticles were fabricated by coordination cobalt(II) ions with amine-terminated triazine polymer and then reduced into Co(0) using sodium borohydride in aqueous medium. The Co(0)-THBP@MCs were fully characterized by FT-IR, SEM–EDX, TEM, and TGA analyses. The presence of metallic cobalt was determined by ICP and XRD techniques. This novel hyperbranched polyaromatic polymer-encapsulated cobalt nanoparticles showed high catalytic activity in Mizoroki–Heck and Suzuki–Miyaura cross-coupling reactions. Heck and Suzuki reactions were carried out using 0.35 and 0.4?mol% of cobalt nanoparticles in which the turnover number (TON) values were calculated as 271 and 225, respectively. In addition, the produced heterogeneous catalyst could be recovered and reused without considerable loss of activity. Oxygen stability and high reusability over 7 runs with trace leaching of the cobalt into the reaction media as well as moisture stability of the immobilized cobalt nanoparticles are their considerable worthwhile advantages.
Highly effective cellulose supported 2-aminopyridine palladium complex (Pd(II)-AMP-Cell?Al2O3) for Suzuki-Miyaura and Mizoroki–Heck cross-coupling
Mhaldar, Pradeep,Pore, Dattaprasad,Rashinkar, Gajanan,Vibhute, Sandip
, (2020/04/15)
In the present work, a novel, highly efficient, retrievable organo–inorganic hybrid heterogeneous catalyst (Pd(II)-AMP-Cell?Al2O3) has been prepared by covalent grafting of 2-aminopyridine on chloropropyl modified cellulose-alumina composite followed by complexation with palladium acetate. The catalyst was characterized by techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), inductive coupled plasma-atomic emission spectroscopy (ICP-AES) and thermo gravimetric analysis (TGA). The catalyst has been successfully employed in Suzuki-Miyaura as well as Mizoroki–Heck cross-coupling reactions. The reactions proceed smoothly resulting in the high yields of cross-coupling products (81 to 95%) within short reaction times. The catalyst can be efficiently recovered by simple filtration and reused for multiple cycles without considerable loss in the catalytic activity. The key-features of the present protocol include mild reaction conditions, simple work-up procedure, high stability of the catalyst, high turnover number (TON) and frequency (TOF), ease recovery and reusability of the catalyst.
Commercially Available CuO Catalyzed Hydrogenation of Nitroarenes Using Ammonia Borane as a Hydrogen Source
Du, Jialei,Chen, Jie,Xia, Hehuan,Zhao, Yiwei,Wang, Fang,Liu, Hong,Zhou, Weijia,Wang, Bin
, p. 2426 - 2430 (2020/03/30)
Tandem ammonia borane dehydrogenation and nitroarenes hydrogenation has been reported as a novel strategy for the preparation of aromatic amines. However, the practical application of this strategy is subjected to the high-cost and tedious preparation of supported noble metal nanocatalysts. The commercially available CuO powder is herein demonstrated to be a robust catalyst for hydrogenation of nitroarenes using ammonia borane as a hydrogen source under mild conditions. Numerous amines (even sterically hindered, halogenated, and diamines) could be obtained through this method. This monometallic catalyst is characteristic of support-free, excellent chemoselectivity, low-cost, and high recyclability, which will favor its future utilization in preparative reduction chemistry. Mechanistic studies are also carried out to clarify that diazene and azoxybenzene are key intermediates of this heterogeneous reduction.
In situ synthesis of carbon nanotube-encapsulated cobalt nanoparticles by a novel and simple chemical treatment process: Efficient and green catalysts for the Heck reaction
Hajipour, Abdol R.,Khorsandi, Zahra,Farrokhpour, Hossein
supporting information, p. 8215 - 8219 (2019/06/07)
In this study, we present a novel, fast and easy method for supporting metal nanoparticles onto the internal surface of multi-walled CNTs; these CNT-encapsulated nanoparticles as heterogeneous, efficient, inexpensive and green catalysts promote the Heck cross-coupling of a large library of functional substrates under mild and sustainable conditions. Remarkably, the introduced catalytic system could be reused for at least nine successive runs without a discernible decrease in its catalytic activity.
Cobalt supported on dendronized magnetic nanoparticles: A new highly efficient and recyclable catalyst for the Mizoroki–Heck cross-coupling reaction
Arghan, Maryam,Koukabi, Nadiya,Kolvari, Eskandar
, (2019/04/26)
Polyamidoamine (PAMAM) is one of the most interesting types of hyperbranched polymers that carry a large number of amino groups on its surface. PAMAM has gained significant attention from synthetic organic chemists due to its structural characteristics, controllable structure, inner porosity, and ability to trap a wide range of ions and molecules. So, in this work, the PAMAM dendrimer was synthesized, grafted onto the surface of magnetite nanoparticles, and the resulting hybrid nanoparticles were then employed as suitable host for immobilizing cobalt nanoparticles. The newly developed catalyst was well characterized by Fourier transform-infrared, X-ray diffraction, thermogravimetric analysis, field emission-scanning electron microscopy, transmission electron microscopy, atomic absorption spectroscopy, element mapping and energy-dispersive X-ray analysis. The efficiency of the as-prepared nanocatalyst was evaluated for the Mizoroki–Heck cross-coupling reactions. The MNP@PAMAM-Co represented perfect catalytic efficiency and high selectivity for the Mizoroki–Heck cross-coupling reaction compared with previously reported catalysts. The catalyst separation from the reaction mixture was easily achieved with the assistance of an external magnetic field, and its recycling was also investigated for five consecutive runs. Hot filtration confirmed no leaching of the active metal during the Heck coupling.
Phenanthroline-based microporous organic polymer as a platform for an immobilized palladium catalyst for organic transformations
Wang, Chang-An,Nie, Kun,Song, Guo-Dong,Li, Yan-Wei,Han, Yin-Feng
, p. 8239 - 8245 (2019/03/21)
Porous organic polymers have attracted significant attention owing to their large specific surface area, excellent chemical and thermal stability, and controllable skeletons. phenanthroline-based microporous organic polymer (Phen-MOP) has been synthesized via a cost-effective method based on the Scholl reaction. The Phen-MOP polymer exhibits high surface area and good stability. Owing to the phenanthroline skeleton embedding into the microporous polymer framework, the Phen-MOP can serve as a platform to support a transition metal catalyst. After being post-modified with palladium acetate, the synthesized Phen-Pd-MOP framework can serve as a highly efficient heterogeneous catalyst for the Suzuki-Miyaura coupling reaction and the Heck coupling reaction. Moreover, the Phen-Pd-MOP catalyst could be reused at least 10-12 times without any significant loss of the catalytic activity.
Synthesis and structural characterization for novel mixed-donor ligand palladium (II) based on graphene and oxime: its application as a highly stable and efficient recyclable catalyst
Ashiri, Samira,Mehdipour, Ebrahim
, p. 2383 - 2393 (2018/08/28)
In this article, the palladium (II) mixed-ligand complex synthesized with reduced graphene oxides containing tetraethoxysilane and menthone oxime was used as an efficient solid catalyst for the Heck coupling reaction. To maintain stability and catalytic activity in the C–C bond reaction, graphene was considered due to the available surface as the solid support. Then, the structure of new heterogeneous catalyst was investigated by FT-IR, UV–Vis DRS, FE-SEM, EDX, AFM, XRD, ICP-OES, Raman, and TGA. The newly synthesized nanocatalyst have beneficial properties, including product’s easy separation, the shorter time to react, purity products (yield 79–99%), and easier work-up procedure. Furthermore, the catalyst was reused six times without significant degradation in catalytic activity and performance.
Organoselenium-palladium(ii) complex immobilized on functionalized magnetic nanoparticles as a promising retrievable nanocatalyst for the "phosphine-free" Heck-Mizoroki coupling reaction
Rangraz, Yalda,Nemati, Firouzeh,Elhampour, Ali
, p. 15361 - 15371 (2018/09/29)
In the present study, for the first time, an air- and moisture-stable organoselenium-palladium complex immobilized on silica-coated magnetic nanoparticles was designed, synthesized and applied as a practical and retrievable catalyst in organic synthesis. The chemical nature and structure of this novel catalytic system were characterized using various techniques such as Fourier transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy and vibrating sample magnetometry (VSM). Subsequently, the catalytic performance of the synthesized nanocatalyst was investigated in the Heck-Mizoroki cross-coupling reaction and excellent results are obtained. The low catalyst loading, wide substrate scope, high yield, short reaction time, simple separation from the reaction mixture and importantly, the longevity of the nanocatalyst for at least five successive recycles without significant degradation in its activity are the main merits of this protocol. Above all, this work opens up attractive and interesting routes for the use of organoselenium compounds as efficient ligands for the synthesis of heterogeneous catalysts.
Ultrahigh performance bio-based polyimides from 4,4′-diaminostilbene
Kumar, Amit,Tateyama, Seiji,Yasaki, Katsuaki,Ali, Mohammad Asif,Takaya, Naoki,Singh, Rajeev,Kaneko, Tatsuo
, p. 182 - 189 (2016/01/09)
We have developed a novel route for the synthesis of high-performance bio-polyimides (PIs) microbially-derived from photo-responsive aromatic diamine 4,4′-diaminostilbene (DAS) and its reduced counterpart 4, 4′-(ethane-1,2-diyl)dianiline (EDDA). DAS and EDDA were condensed with various commercially-available dianhydrides to obtain a series of poly(amic acid)s (PAAs) and PIs which were characterized in terms of their thermal, mechanical, and photo-functions. These bio-based PAAs showed a very high viscosity of 6.62 dL/g, and the PIs showed ultrahigh thermal resistance with Td10 values over 600 °C, which were higher than that of any bio-based plastic reported thus far. They also showed Tg values above 250 °C, and tensile strength of over 132 MPa, which is higher than that of Kapton. The PIs also showed photo-functional behavior based on stilbene-based photoreactions.
