KINETIC STUDIES ON THE PEROXYOXALATE REACTION IN PARTIALLY AQUEOUS MEDIA

• Grant number: 23/06430-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2023
• End date: August 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Joséf Wilhelm Baader
• Grantee: Mariana Rocha
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The peroxyoxalate reaction, discovered in 1963 by Chandross, has been the subject of several scientific studies over the past decades. The interest in the study of this reaction is mainly motivated by its wide applicability in analytical assays, which makes different research groups to perform studies to elucidate the mechanism of this chemiluminescent reaction. The peroxyoxalate system is studied in anhydrous medium, however, for the application of the system in bioanalytical assays it is of great importance to perform this reaction in aqueous and partially aqueous media, where the assays obviously also are more friendly environmentally. The presence of water in the medium implies an increase in the speed of the peroxyoxalate reaction and a decrease in the intensity of the light emitted. Despite this, in these media the reaction tends to present a very pronounced emission peak, resulting in a very consistent analytical signal, which is a favorable factor for its application. Thus, the study of the peroxyoxalate reaction in media with the presence of water is essential to understand the changes in the behavior of the system as the concentration of water in the solvent changes. In this research project kinetic studies of the peroxyoxalate reaction in partially aqueous medium will be carried out, promoted by strong non-nucleophilic bases as catalysts, using esters of different reactivities as substrates to study their relative rates of perhydrolysis in media with different water concentration, and compare their relative reactivity in aqueous media with that in anhydrous conditions.