A facile route to transfer Cu nanoparticles to organic medium for better stabilization and improved photocatalytic activity towards N-formylation reaction

Abstract

Cu nanoparticles were prepared in an aqueous phase by means of a simple reduction-route using sodium borohydride as the reducing agent in the presence of ascorbic acid and polyvinylpyrrolidone (PVP). The hydrosol of the Cu nanoparticles deteriorated within a day. It compelled to initiate a scheme to stabilize the nanoparticles for a long period of time. Phase transfer to organic solvents using Benzyldimethylstearylammonium chloride (BDSAC) as a phase transfer agent was found to be an effective path in this respect. BDSAC performed the dual role of dragging the Cu nanoparticles from water to organic solvent and also acted as a capping agent along with PVP for better stabilization of Cu nanoparticles. The organosol of the Cu nanoparticles exhibited excellent stability and promising catalytic activity towards N-formylation reactions on a number of amine substrates in presence of visible green LED light. The yield and reusability of the catalyst were promising. All the samples were thoroughly characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, energy dispersive analysis of x-rays, x-ray photoelectron spectroscopy and thermo gravimetric analysis .

Sodium Citrate and Polyvinylpyrrolidone Captured Silver Nanoparticles Transfer to Organic Solvents

“…In the literature, there are several methods to disperse the nanoparticles in organic solvents -NP transfer from aqueous solution by shell changing, centrifugation, solvent evaporation and NP powder redispersion in organics [10]- [13], silver nanoparticles can be synthesised directly in an organic solvent like toluene [14], [15]. Despite so many methods, there are still several challenges associated with NP transfer to organic media, like transfer efficiency, repeatability and stability.…”