One-pot Synthesis of β-acetamido-β-(phenyl) Propiophenone using ZnO/Carbon Nanocomposites

Abstract

The focus of the present work is to synthesize ZnO/C composite using dextrose as carbon source by combustion method and study the comparative evaluation on one-pot synthesis of β-acetamido- β-(phenyl) propiophenone over ZnO nanoparticles and ZnO/C composite catalyst. The ZnO nanoparticles has been synthesized by sol-gel method using zinc nitrate and NaOH and ZnO/Carbon composites by combustion method using zinc nitrate and dextrose as carbon source. The resulting gel was placed in a preheated muffle furnace at 400oC. The solution boils and ignites with a flame. On cooling highly amorphous powder of ZnO/Carbon composite is obtained. The XRD patterns reveal the hexagonal phase with Wurtzite structure and the nanocrystalline nature of the catalysts. The SEM image of ZnO/C composite showed that it contains spherical particles with an average size of 41 nm. The average particle size of the composite was around 60nm by DLS method. The catalytic activity of the ZnO/Carbon composites has been analyzed by one-pot four-component condensation of benzaldehyde, acetophenone, acetyl chloride and acetonitrile. The feed molar ratio of 1:1 (Bz:AP) and catalyst loading of 30 mol% is found to be the optimal condition for β-acetamido ketone conversion over ZnO/carbon composite. The substantial catalytic activity of the synthesized ZnO/C composite materials was tested by one-pot four-component condensation of benzaldehyde (Bz), acetophenone (AP), acetyl chloride (AC) and acetonitrile (AN) which showed a high β-acetamido ketone conversion under the optimized reaction conditions. It has also been found that the catalyst is very stable and reusable.