6589-48-6Relevant articles and documents
Amine grafted Fe3O4 immobilized graphene oxide as a recyclable and effectual nanocomposite for the regioselective ring opening reaction
Gupta, Padmini,Garkoti, Charu,Shabir, Javaid,Surabhi,Sah, Digvijay,Mozumdar, Subho
, p. 4013 - 4028 (2021/06/25)
This work describes the synthesis of magnetic graphene oxide (MGO), where iron oxide (Fe3O4) nanoparticles were uniformly deposited over the sheets of the graphene oxide (GO). Further, the introduction of aminopropyltrimethoxysilane (APTMS) on the surface of MGO was successfully done and results in the formation of amine-functionalized magnetic graphene oxide (MGO–NH2). The synthesized heterogeneous magnetic nanocomposite was characterized by numerous physicochemical and morphological techniques such as powder X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, transmission electron microscopy, vibrating sample magnetometer, scanning electron microscopy, CHN analyzer, and energy-dispersive X-ray analysis. The synthesized nanocomposite was proved to be an effectual catalyst in the nucleophilic ring opening reactions of styrene oxide with derivatives of amines under green solvent. The present catalyst displayed good catalytic activity, short reaction time, higher regioselectivity, excellent yields and could be reutilized up to seven catalytic rounds with no substantial loss in its activity. The excellent properties of the catalyst are due to the dual character of acidic groups (existence of carboxyl groups on the sheet edges) and basic groups (amine groups anchored on the surface of GO). On completion of the reaction, the prepared nanocomposite could be effortlessly recovered from the reaction mixture by utilizing an external magnet, owing to the ferromagnetic property of Fe3O4. Graphical Abstract: [Figure not available: see fulltext.].
Zirconium triflate grafted on SBA-15 as a highly efficient solid acid catalyst for ring opening of epoxides by amines and alcohols
Tayade, Kamlesh N.,Wang, Lianyue,Shang, Sensen,Dai, Wen,Mishra, Manish,Gao, Shuang
, p. 758 - 766 (2017/04/24)
Metal (Al, Ti, Zr) triflate grafted mesoporous SBA-15 (AlTf/S, TiTf/S, ZrTf/S) samples were synthesized as inexpensive solid acid materials by a simple one-pot-two-step synthesis methodology. These materials were characterized by X-ray diffraction, N2-sorption, thermogravimetric analysis, Fourier transform infrared spectroscopy (FT-IR), in-situ pyridine FT-IR spectroscopy, and elemental analysis. ZrTf/S was found to be a highly efficient and reusable solid acid catalyst for ring opening of epoxides with amines and alcohols and produced β-amino alcohols and β-alkoxy alcohols respectively under ambient reaction conditions. The ZrTf/S catalyst showed the highest activity, which was attributed to its high acidity compared with that of the Ti and Al containing samples.
Manganese Complexes of Pyrrole- and Indolecarboxamide Ligands: Synthesis, Structure, Electrochemistry, and Applications in Oxidative and Lewis-Acid-Assisted Catalysis
Yadav, Sunil,Kumar, Sushil,Gupta, Rajeev
, p. 5534 - 5544 (2015/12/01)
This work shows the synthesis and structural, spectroscopic, and electrochemical properties of MnIII complexes supported with pyrrole- and indolecarboxamide ligands. In all cases, the respective ligand constitutes a N4 coordination sphere about the MnIII ion. The MnIII complexes of pyrrolecarboxamide ligands are square pyramidal with a fifth Cl atom, whereas analogous complexes of indolecarboxamide ligands are essentially square planar. Electrochemical studies reveal highly negative MnIII/II and moderately positive MnIV/III redox potentials. In situ generated Mn4+ species of the pyrrolecarboxamide ligands were characterized by absorption and electron paramagnetic resonance spectroscopy. All complexes functioned as catalysts in olefin epoxidation reactions by using PhIO as the oxo-transfer agent. All complexes also acted as Lewis acid catalysts for ring-opening reactions of assorted epoxides with various nucleophiles. We also show a one-pot, two-step epoxidation reaction followed by ring opening, which illustrates the catalytic significance of the present complexes. Importantly, MnIII complexes carrying electron-donating substituents on the ligand were found to be better catalysts.
