The oxythallation of certain 1, 3-dienes with thallium (III) nitrate trihydrate in MeOH–CH 2 Cl 2 at 0–20° C gave products after vinyl migration. Methyl 1-methylcyclopropyl ketone, obtained in the reaction of 2, 3-dimethyl-1, 3-butadiene, was presumably derived from a cyclopropylmethyl cation, an intermediate in the vinyl migration.
