Functional group analysis during ozonation of sunflower oil methyl esters by FT-IR and NMR.
Ozonation of neat sunflower oil (SFO) methyl esters was monitored by FT-IR and 1H and 13C NMR spectroscopy. During the early stage of ozonation, ozone absorption was essentially quantitative. This was accompanied by the formation of 1,2,4-trioxolane. IR and NMR spectra of ozonated samples showed that scission of ozonide to give aldehyde were minimal. 1H NMR analysis revealed that the amount of ozonide relative to aldehyde was more than 90% regardless of the extent of ozonation. Complete ozonation was attained after supplying around 0.20 g O3/ml methyl ester after which ozone absorption suddenly dropped to around 25%. At the latter part of ozonation, ozonide and aldehyde reacted with excess ozone to give carboxylic acid. Reaction products were identified according to Criegee mechanism.
Soriano
Nestor U
NU
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-0006, Japan.
Migo
Veronica P
VP
Matsumura
Masatoshi
M
D000447:Aldehydes / Q000032:analysis / Q000737:chemistry; D004951:Esterification; D004952:Esters / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010126:Ozone / Q000032:analysis / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D000074242:Sunflower Oil
D000447:Aldehydes; D004952:Esters; D010938:Plant Oils; D000074242:Sunflower Oil; D010126:Ozone