Abstract: Low-temperature ozonation of aliphatic and aromatic acetals leads to oxygen-rich intermediates, acetal hydrotrioxides 1-3, the NMR spectra of which show two absorptions at 6 13 ppm downfield from Me+%. Decomposition of these compounds, which affords among other products singlet oxygen and peroxides, involves nonradical and radical processes. The kinetics of decomposition has been studied by NMR spectroscopy and activation ...