All the identities were confirmed by a comparison of the IR and NMR spectra. The dl-limonen- 4-ol (1, 8 p-menthadien-4-ol) was obtained as a major product (11% based on the sample taken), while d-trans-carveol, cis-carveol, perillyl alcohol, limonen-10-ol (1, 8 p-menthadien- 10-ol), and carvone were obtained as minor products (total, 6.5%). In a study of the mechanism by which olefins are oxidized with selenium dioxide, Schaefer and