10.1039/c8nj00410b
The research focuses on the development and investigation of the catalytic activity of copper nanoparticles (CuNPs) supported on a Zinc oxide-polythiophene (ZnO-PTh) nanocomposite, denoted as CuNPs@ZnO-PTh. The purpose of this study was to create an efficient, cost-effective, and environmentally benign catalyst for the synthesis of propargylamine, tetra-substituted propargylamine, and pyrrolo[1,2-a]quinolines through A3 and KA2 coupling reactions. The researchers used a variety of chemicals in the synthesis process, including zinc chloride, sodium hydroxide, sodium dodecyl sulfate, thiophene, ferric chloride, copper nitrate trihydrate, and hydrazine hydrate. The conclusions drawn from the study highlight the high catalytic performance of the CuNPs@ZnO-PTh catalyst, which was attributed to its high surface area and the synergistic effect of both CuNPs and ZnO-PTh. The catalyst demonstrated excellent activity, selectivity, and recyclability, with the reactions yielding high product yields (up to 98%) in ethylene glycol, a green and biodegradable solvent, under microwave irradiation. The study concludes that this protocol is more efficient and sustainable compared to existing commercial methods.
10.1016/j.inoche.2019.107666
The research focuses on the synthesis and catalytic application of two transition-metal containing heteropolyniobates, H[Ni(en)3]5[VNb12O40(VO)2]?15H2O (1) and H3[Cu(en)2]4[VNb12O40(VO)2]?13H2O (2). These compounds were synthesized using ethylene glycol and water as a mixed solvent, with ethylenediamine (en), nickel(II) chloride hexahydrate (NiCl2·6H2O), copper(II) nitrate trihydrate (Cu(NO3)2·3H2O), potassium hexaniobate (K7HNb6O19·13H2O), and sodium vanadate (NaVO3) playing crucial roles in the solvothermal synthesis process. The resulting compounds exhibited remarkable catalytic performance for the cyanosilylation of various aldehydes and ketones, yielding cyanohydrin trimethylsilyl ethers with high efficiency. The study highlights the importance of the synergistic effect between the polyoxoniobate anions and transition-metal chelates in enhancing the catalytic activity, with catalyst 1 achieving a turnover frequency (TOF) of 515.5 h-1 for benzaldehyde cyanosilylation at a loading of 0.1 mol%.