23359-08-2Relevant academic research and scientific papers
Dual Nickel/Ruthenium Strategy for Photoinduced Decarboxylative Cross-Coupling of α,β-Unsaturated Carboxylic Acids with Cycloketone Oxime Esters
Gao, Ang,Jiang, Run-Chuang,Liu, Chuang-Chuang,Liu, Qi-Le,Lu, Xiao-Yu,Xia, Ze-Jie
supporting information, p. 8829 - 8842 (2021/06/30)
Herein, a dual nickel/ruthenium strategy is developed for photoinduced decarboxylative cross-coupling between α,β-unsaturated carboxylic acids and cycloketone oxime esters. The reaction mechanism is distinct from previous photoinduced decarboxylation of α,β-unsaturated carboxylic acids. This reaction might proceed through a nickelacyclopropane intermediate. The C(sp2)-C(sp3) bond constructed by the aforementioned reaction provides an efficient approach to obtaining various cyanoalkyl alkenes, which are synthetically valuable organic skeletons in organic and medicinal chemistry, under mild reaction conditions. The protocol tolerates many critical functional groups and provides a route for the modification of complex organic molecules.
Synthesis and characterization of two novel biological-based nano organo solid acids with urea moiety and their catalytic applications in the synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol), coumarin-3-carboxylic acid and cinnamic acid derivatives under mild and green conditions
Zolfigol, Mohammad Ali,Ayazi-Nasrabadi, Roya,Baghery, Saeed
, p. 71942 - 71954 (2015/09/08)
2-Carbamoylhydrazine-1-sulfonic acid and carbamoylsulfamic acid as novel, mild and biological-based nano organocatalysts with urea moiety were designed, synthesized and fully characterized by FT-IR, 1H NMR, 13C NMR, mass spectrometry, elemental analysis, thermal gravimetric, derivative thermal gravimetric, X-ray diffraction patterns, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy and UV/Vis analysis. The catalytic applications of 2-carbamoylhydrazine-1-sulfonic acid and carbamoylsulfamic acid were studied in the synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol), coumarin-3-carboxylic acid and cinnamic acid derivatives via the condensation reaction between several aromatic aldehydes and 1-phenyl-3-methylpyrazol-5-one (synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols)), the Knoevenagel condensation of Meldrum's acid with salicylaldehyde derivatives (synthesis of coumarin-3-carboxylic acids) and the condensation of Meldrum's acid with aromatic aldehydes (synthesis of cinnamic acids) under mild and solvent-free conditions. In the presented studies, some products were formed and reported for the first time. The described nano organo solid acids have potential in industry.
Palladium nanoparticles on β-cyclodextrin functionalised graphene nanosheets: A supramolecular based heterogeneous catalyst for C-C coupling reactions under green reaction conditions
Putta, Chandrababu,Sharavath, Vittal,Sarkar, Suprabhat,Ghosh, Sutapa
, p. 6652 - 6660 (2015/03/05)
The use of functional properties of native cyclodextrins in palladium nanoparticle-β-cyclodextrin-graphene nanosheet (Pd@CD-GNS) catalyzed carbon-carbon (C-C) coupling reactions have been investigated under green reaction conditions. The supramolecular catalyst was prepared by deposition of Pd nanoparticles (Pd NPs) on CD-GNS using ethanol as the greener solvent and in situ reducing agent. The catalyst was characterised by FTIR, XRD, RAMAN, UV-Vis spectroscopy, TEM, SAED, XPS and ICP-AES. The catalytic activity of these catalysts is investigated in C-C coupling reactions such as Suzuki-Miyaura and Heck-Mizoroki reactions of aryl bromides and aryl chlorides containing functional groups under green reaction conditions i.e. in water, under phosphine free and aerobic conditions. This catalyst afforded excellent selectivities for the products in good to excellent yields under low Pd loadings (0.2-0.05 mol%), while ensuring the recovery and reusability of the catalysts. The reused catalyst was characterized by FTIR, TEM, XPS and ICP-AES. The CD supramolecular mediators loaded on GNS act as stabilising agents for the Pd NPs. The excellent catalytic activity of this system was attributed to the presence of CDs, excellent dispersibility in water, hydrophobic nature of the GNS support for the accumulation of organic substrates in water, "Breslow effect", the presence of PTC to overcome the mass transfer limitation onto the surface of GNS and formation of ternary CD/substrate/additive complexes on the Pd-GNS surface.
Palladium nanoparticles on noncovalently functionalized graphene-based heterogeneous catalyst for the Suzuki-Miyaura and Heck-Mizoroki reactions in water
Sharavath, Vittal,Ghosh, Sutapa
, p. 48322 - 48330 (2014/12/10)
We describe here a methodology to synthesize a reusable heterogeneous catalyst based on palladium nanoparticles (Pd NPs) supported on noncovalently functionalized graphene using 1-pyrene carboxylic acid. This can be used efficiently for Suzuki-Miyaura and Heck-Mizoroki reactions in water up to five cycles, providing excellent yields with high selectivity of cross coupled products. It is also useful for more challenging substrates like electron-rich and electron-poor bromoarenes and chloroarenes which resulted in good isolated yields (alkenes and biphenyls) in pure water. Use of functionalized graphene in the catalyst preparation improved the dispersion of it in water medium and also acted as a stabilizing agent for the Pd NPs. The percentage of metal loading in the catalyst and its thermal stability were determined by inductively coupled plasma atomic emission spectroscopy and thermo gravimetric analysis respectively. The composite formation was confirmed by X-ray diffraction patterns, Fourier transform infrared spectroscopy and Raman spectroscopy. The surface elemental composition with oxidation state was determined by UV-visible and X-ray photoelectron spectroscopy. The size and morphology of the Pd NPs on the functionalized graphene sheets were directly observed by Transmission Electron Microscopy.
