832-01-9Relevant academic research and scientific papers
Synthesis of novel 1-phenyl-benzopyrrolizidin-3-one derivatives and evaluation of their cytoneuroprotective effects against NMDA-induced injury in PC12 cells
Cao, Jiafu,Li, Qiji,Liao, Xiu,Wang, Enhua,Wang, Li,Yang, Juan,Yang, Lishou,Yang, Qian,Yang, Xiaosheng,Yang, Yan
supporting information, (2022/02/23)
A range of novel 1-phenyl-benzopyrrolizidin-3-one derivatives were synthesized and evaluated for neuroprotective effects against N-methyl-?-aspartate (NMDA)-induced injury in PC12 cells. Interestingly, derivatives that 1-phenyl moiety bearing electron-donating group, especially benzyloxy, and the trans-forms exhibited better protective activity against NMDA-induced neurotoxicity. Compound 11 m demonstrated the best neuroprotective potency and shown a dose-dependent prevention. The increased intracellular calcium (Ca2+) influx caused by NMDA in PC12 cells was reversed in the case of compound 11 m pretreatment at 15 μM. These results suggested that the synthesized 1-phenyl-benzopyrrolizidin-3-one derivatives exerted neuroprotective effect on NMDA-induced excitotoxicity in PC12 cells associated with inhibition of Ca2+ overload and can be further optimized for the development of neuroprotective agents.
Pd-Catalyzed desulfitative arylation of olefins by: N -methoxysulfonamide
Ojha, Subhadra,Panda, Niranjan
supporting information, p. 1292 - 1298 (2022/02/19)
A novel Pd-catalyzed protocol for the desulfitative Heck-type reaction of N-methoxy aryl sulfonamides with alkenes was reported. The cross-coupling reaction was performed successfully with a variety of olefins to obtain aryl alkenes. Different substituents on the aromatic ring of N-methoxysulfonamides were also found to be compatible with the reaction conditions. Expectedly, the reaction proceeds through CuCl2-promoted generation of the nitrogen radical and subsequent desulfonylation under thermal conditions to afford the aryl radical for the Pd-catalyzed coupling reaction. N-Methoxysulfonamide was further exploited for the synthesis of symmetrical biaryls in the presence of CuCl2. This journal is
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.
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.
Pd Nanoparticles Stabilized on the Cross-Linked Melamine-Based SBA-15 as a Catalyst for the Mizoroki–Heck Reaction
Amiri, Mandana,Bezaatpour, Abolfazl,Mikkola, Jyri-Pekka,Murzin, Dmitry Yu.,Nuri, Ayat,Vucetic, Nemanja
, (2021/06/16)
Mesoporous SBA-15 silicate with a high surface area was prepared by a hydrothermal method, successively modified by organic melamine ligands and then used for deposition of Pd nanoparticles onto it. The synthesized materials were characterized with infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nitrogen physisorption, scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) and inductively coupled plasma (ICP-OES). The catalyst was effectively used in the Mizoroki–Heck coupling reaction of various reactants in the presence of an organic base giving the desired products in a short reaction time and with small catalysts loadings. The reaction parameters such as the base type, amounts of catalyst, solvents, and the temperature were optimized. The catalyst was easily recovered and reused at least seven times without significant activity losses. Graphic Abstract: [Figure not available: see fulltext.]
Aryl Diazonium Salts: Powerful Arylating Agents for Catellani-Typeortho-Arylation
Fu, Ying,Guo, Liang-Liang,Zhang, Yu-Xia
, p. 17437 - 17444 (2021/12/02)
The Catellani reaction provides an efficient synthetic approach to polyfunctionalized arenes. However, the selectiveortho-arylating reagents employed in these reactions have been strictly limited to activated bromoarenes. As demonstrated in this work, aryl diazonium salts bearing both electron-donating and electron-withdrawing substituents, after in situ transformations with KI into the corresponding iodoarenes, were efficient arylating reagents for Catellani typeortho-arylation approaches.
Photocatalytic Oxidative [2+2] Cycloelimination Reactions with Flavinium Salts: Mechanistic Study and Influence of the Catalyst Structure
Hartman, Tomá?,Reisnerová, Martina,Chudoba, Josef,Svobodová, Eva,Archipowa, Nataliya,Kutta, Roger Jan,Cibulka, Radek
, p. 373 - 386 (2021/02/01)
Flavinium salts are frequently used in organocatalysis but their application in photoredox catalysis has not been systematically investigated to date. We synthesized a series of 5-ethyl-1,3-dimethylalloxazinium salts with different substituents in the positions 7 and 8 and investigated their application in light-dependent oxidative cycloelimination of cyclobutanes. Detailed mechanistic investigations with a coumarin dimer as a model substrate reveal that the reaction preferentially occurs via the triplet-born radical pair after electron transfer from the substrate to the triplet state of an alloxazinium salt. The very photostable 7,8-dimethoxy derivative is a superior catalyst with a sufficiently high oxidation power (E=2.26 V) allowing the conversion of various cyclobutanes (with Eox up to 2.05 V) in high yields. Even compounds such as all-trans dimethyl 3,4-bis(4-methoxyphenyl)cyclobutane-1,2-dicarboxylate can be converted, whose opening requires a high activation energy due to a missing pre-activation caused by bulky adjacent substituents in cis-position.
Pd/Cu-free Heck and Sonogashira coupling reactions applying cobalt nanoparticles supported on multifunctional porous organic hybrid
Hajipour, Abdol R.,Khorsandi, Zahra
, (2020/02/11)
A new heterogeneous cobalt catalyst has been synthesized by immobilizing Co species onto a nitrogen-rich porous organic polymer (Co@imine-POP). The heterogeneous catalyst synthesized was efficient in Heck and Sonogashira cross-coupling reactions in green media under mild reaction conditions without inert air and phase transfer agents. This phosphine-, copper-, and palladium-free catalyst was stable under the reaction conditions and could be reused for at least eight successive runs without a discernible decrease in its catalytic activity.
Novel and efficient polymer supported copper catalyst for heck reaction
Anas, Saithalavi,Anjali, Suresh,Sruthi, Pambingal Rajan,Varghese, Nicy
, (2020/07/08)
A novel polymer supported copper complex (m-PAN-Cu) is prepared by immobilizing Cuprous Iodide (CuI) on amidoxime modified Polyacrylonitrile (mPAN) and characterised by FTIR, XRD, EDX, ICP-MS and XPS analyses. This complex was further explored as a general and efficient heterogeneous catalyst for Heck coupling reaction of a series of aryl halides with olefins and afforded the corresponding coupling products in moderate to good yields. This catalyst offers easy preparation, good stability, excellent catalytic activity and reusability. This is the first study involving an amidoxime modified PAN supported copper catalyst towards greener and efficient Heck reaction.
Pd nanoparticles supported on reduced graphene oxide as an effective and reusable heterogeneous catalyst for the Mizoroki–Heck coupling reaction
Mirza-Aghayan, Maryam,Mohammadi, Marzieh,Addad, Ahmed,Boukherroub, Rabah
, (2020/02/05)
A general method for the synthesis of palladium nanoparticles loaded on reduced graphene oxide functionalized with diethylenetriamine (PdNPs/rGO-NH2) using a sonochemical procedure is described. The heterogeneous nanocomposite was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray, thermogravimetric analysis, high-angle annular dark field scanning transmission electron microscopy, X-ray photoelectron spectroscopy, UV–visible absorption, and inductively coupled plasma optical emission spectrometry. The PdNPs/rGO-NH2 was very effective for the Mizoroki–Heck coupling reaction of several aryl iodide compounds with different alkenes in the presence of triethylamine. The reaction provides the coupling products in good to excellent yields (59–100%). Additionally, the PdNPs/rGO-NH2 catalyst can be reutilized for six successive runs without any apparent diminution of its catalytic reactivity.
