2439-77-2Relevant articles and documents
Nano-construction of CuO nanorods decorated with g-C3N4 nanosheets (CuO/g-C3N4-NS) as a superb colloidal nanocatalyst for liquid phase C[sbnd]H conversion of aldehydes to amides
Mohammadi, Robabeh,Gholipour, Behnam,Alamgholiloo, Hassan,Rostamnia, Sadegh,Mohtasham, Hamed,Zonouzi, Afsaneh,Ramakrishna, Seeram,Shokouhimehr, Mohammadreza
, (2021)
Herein, we describe an intelligent strategy to fabricate nanosheets of graphitic carbon nitride (g-C3N4) decorated with nanorods copper oxide (CuO NRs). Then, the catalytic activity of CuONRs/g-C3N4-NS was developed for the synthesis of primary amides in water. The morphology of CuO and its synergetics effect with nanosheets g-C3N4 a major role in the yield of products. Furthermore, hydroxylamine hydrochloride (NH2OH·HCl) due to availability and affordability was used as a suitable substitute for ammonia source. The findings demonstrate that this layer nanostructure is a superb catalyst for converting various derivatives of aldehyde to their corresponding amides. The current protocol can be useful criterion in the synthesis and stabilization of metal oxides and provides new insight in organic transformation.
Uniformly dispersed copper nanoparticles onto the modified magnetically recoverable nanocatalyst for aqueous synthesis of primary amides
Ziaee, Fariborz,Gholizadeh, Mostafa,Seyedi, Seyed Mohammad
, (2018)
Magnetically recoverable and environmentally friendly Cu-based heterogeneous catalyst has been synthesized for the one-pot conversion of aldehydes to their corresponding primary amides. The Fe3O4@SiO2 nanocomposites were prepared by synthesis of Fe3O4 magnetic nanoparticles (MNPs) which was then coated with a silica shell via St?ber method. Bi-functional cysteine amino acid was covalently bonded onto the siliceous shell of nanocatalyst. The CuII ions were then loaded onto the modified surface of nanocatalyst. Finally, uniformly dispersed copper nanoparticles were achieved by reduction of CuII ions with NaBH4. Amidation reaction of aryl halides with electron-withdrawing or electron-donating groups and hydroxylamine hydrochloride catalyzed with Fe3O4@SiO2@Cysteine-copper (FSC-Cu) MNPs in aqueous condition gave an excellent yield of products. The FSC-Cu MNPs could be easily isolated from the reaction mixture with an external magnet and reused at least 8 times without significant loss in activity.
Product selectivity controlled by manganese oxide crystals in catalytic ammoxidation
Hui, Yu,Luo, Qingsong,Qin, Yucai,Song, Lijuan,Wang, Hai,Wang, Liang,Xiao, Feng-Shou
, p. 2164 - 2172 (2021/09/20)
The performances of heterogeneous catalysts can be effectively tuned by changing the catalyst structures. Here we report a controllable nitrile synthesis from alcohol ammoxidation, where the nitrile hydration side reaction could be efficiently prevented by changing the manganese oxide catalysts. α-Mn2O3 based catalysts are highly selective for nitrile synthesis, but MnO2-based catalysts including α, β, γ, and δ phases favour the amide production from tandem ammoxidation and hydration steps. Multiple structural, kinetic, and spectroscopic investigations reveal that water decomposition is hindered on α-Mn2O3, thus to switch off the nitrile hydration. In addition, the selectivity-control feature of manganese oxide catalysts is mainly related to their crystalline nature rather than oxide morphology, although the morphological issue is usually regarded as a crucial factor in many reactions.
Aerobic oxidation of primary amines to amides catalyzed by an annulated mesoionic carbene (MIC) stabilized Ru complex
Yadav, Suman,Reshi, Noor U Din,Pal, Saikat,Bera, Jitendra K.
, p. 7018 - 7028 (2021/11/17)
Catalytic aerobic oxidation of primary amines to the amides, using the precatalyst [Ru(COD)(L1)Br2] (1) bearing an annulated π-conjugated imidazo[1,2-a][1,8]naphthyridine-based mesoionic carbene ligand L1, is disclosed. This catalytic protocol is distinguished by its high activity and selectivity, wide substrate scope and modest reaction conditions. A variety of primary amines, RCH2NH2 (R = aliphatic, aromatic and heteroaromatic), are converted to the corresponding amides using ambient air as an oxidant in the presence of a sub-stoichiometric amount of KOtBu in tBuOH. A set of control experiments, Hammett relationships, kinetic studies and DFT calculations are undertaken to divulge mechanistic details of the amine oxidation using 1. The catalytic reaction involves abstraction of two amine protons and two benzylic hydrogen atoms of the metal-bound primary amine by the oxo and hydroxo ligands, respectively. A β-hydride transfer step for the benzylic C-H bond cleavage is not supported by Hammett studies. The nitrile generated by the catalytic oxidation undergoes hydration to afford the amide as the final product. This journal is
