Analysis of Ozonides and Peroxidic Compounds from Methyl Oleate Ozonation O. E. Ledea, J. Moleiro, M. Diaz, D. Jardines, A. Rosado(1), T. Correa(1). Ozone Research Center, Cuba. 1 - National Center for Scientific Research, Cuba. Methyl oleate ozonation, in hexane (non participating solvent) at a concentration of 0.3 M and in presence of protic substances, such as ethanol and water, was carried out. A bubbling reactor at 25 C, with an ozone dose of 50 mg per gram of sample was used. Proton Nuclear Magnetic Resonance (H1-NMR) and Gas Chromatography/Mass Spectrometry (GC/MS) techniques, in order to identify the reaction products in all the studied conditions, were used. During ozonation of methyl oleate in hexane, the corresponding ozonides/oligomeres were identified. It was design a simple procedure for GC/MS determination of ozonides, combining the quantitative methylation with the analysis of the thermal decomposition products of the ozonides. The procedure used for this determination was not previously reported. The ozonides were separated from the reaction mixture by means of the high performance liquid chromatography (HPLC), using an isocratic system. On the other hand, when ethanol is used as additive, the ethoxy-hydroperoxides were identified as major products. Ozonides, in smaller proportion, are observed too. For the analysis of these compounds by GC/MS, the same procedure for the determination of ozonides, was used. The gas chromatography profile obtained is discussed in detail and it is corroborated by the H1-NMR analysis. The analysis of the reaction products, when water was used as additive, revealed only the presence of aldehydes (hexanal, nonanal and 9-oxo-methyl nonanoate) for both techniques. The obtained products, in all cases, can be explained taking into account the Crieggee mechanism. Source: 2nd International Symposium on Ozone Applications Havana, Cuba - Mach 24-26, 1997.