T 2067 ( OTTO) Thallium(III) nitrate trihydrate, CAS NO 13453-38-8 Reagent for the rapid oxidation of styrene derivatives to carbonyl compounds, for the regioselective ring expansion of cyclic aralkyl ketones via oxidative rearrangement,[2] for the selective hydrolysis of thioacetals to carbonyl compounds and for a general synthetic method to 19-norsteroids.Mediates ring contraction of cyclic ketones to a series of trans-fused 10-methyl-2-decalones.