Nanomaterials and Nanotechnology

Biography

Biography: Amparo Luna

Abstract

Allenes are a class of compounds with two cumulative carbon-carbon double bonds, which are versatile synthetic intermediates in organic synthesis. These substrates have allowed chemists to prepare a variety of compounds of chemical and biological interest. The abundance of nitrogen-containing heterocycles in biologically active  molecules has occasioned many efforts for their synthesis and functionalization. In particular, the oxacycles is important because they are present in a wide range of natural products. On the other hand, in the design of eco-friendly processes, catalysts and solvents play a key factor from both an economic and environmental point of view. In the development of new chemical processes the reactions conditions should fulfill specific criteria: i) renewable feedstocks, ii) low VOC emission, iii) low flammability and iv) functional group compatibility. In our continuing efforts on the construction of potentially bioactive heterocycles, we have developed a new catalytic process using metal nanoparticles because of; NPs tend to be more reactive than their particulate metal counterparts as a result of increasing surface area with decreasing particle size. Palladium nanoparticles are one of the most used and efficient catalyst in the formation of C-C bond and other chemical transformations such as carbon-hetero atom bond formation. Herein, we described the use, for the first time, of a novel ligand-free catalytic system for obtaining the cyclization of allenols towards the preparation of  dihydrofurans and carbazoles. The prepared nanomaterial (PdNPs) displayed good activity on the construction of potentially bioactive heterocycles in aqueous media, providing good to excellent yields. The recyclability of the nanocatalyst has also been established (up to four cycles) giving rise to good isolated yields in successive runs.