Deep eutectic solvents (Reline) and Gold Nanoparticles Supported on Titanium Oxide (Au-TiO2) as New Catalysts for synthesis some substituted phenyl(substituted-3-phenyloxiran)methanone Enantioselective Peroxidation

Background: The eco-friendly power of hydrogen peroxide oxidant produced water that was the only by-product after oxidation. Unfortunately, its oxidation power towards chalcones and chalcones analogs was substantially low, and therefore, it was normally used together with a catalyst or converted to hydroperoxides in order to improve its oxidation power. Objective: This research aimed to study epoxidation chemistry. Hence, hydrogen peroxide was used as a potential oxidant for epoxidation with different techniques and catalysts. Methodology: Advantageous effects of (reline) (derived from two moles of choline chloride and one mole of urea) as a deep eutectic solvent (DES) or the gold (Au) catalyst nanoparticles (NPs) supported on titanium oxide (Au-TiO2) on the chalcone derivatives of peroxidation was studied under several procedure conditions using hydrogen peroxide/sodium bicarbonate to produce novel oxiranes (I-VI). Results and Discussion: Acceptable results were obtained by method (B) using hydrogen peroxide/sodium bicarbonate - (reline) mixture, which gave 87- 90% peroxidation results in a short time (4 h) in comparison with less than 86% and 24 h of the conventional method (A), while using the Au NPs supported on titanium oxide (Au-Ti02); that is, Method (C) gave the best percentage yield of 90-95 % and time (about 2 h), which is about half of that of (Reline) mixture. Such a condition may be due to high activation of hydrogen peroxide by Au and titanium oxide nanoparticles and low viscosity of the reaction mixture. Conclusions: The chalcones epoxidations would convince chemists that using the deep eutectic solvent (Reline) and the Au-supported on titanium oxide NPs for catalysing these reactions are techniques of great importance in various branches of oxidation.