Polystyrene-bound diaryl selenoxide and telluroxide have been prepared, which behaved as mild oxidizing agents for thiols to disulfides, phosphines to phosphine oxides, hydroquinone and catechol to p- and o-benzoquinones, and thioketones to oxo compounds. The telluroxide completed these reactions in shorter periods or under milder conditions than the selenoxide. In addition, they effected novel solvent-dependent reactions of thioamides involving thioureas to 1,2,4-thiadiazoles or to nitriles. In nonacidic solvents, the dehydrosulfurization to nitriles occurred in preference to the oxidative dimerization to 1,2,4-thiadiazoles, but an acidic solvent such as acetic acid promoted the latter reaction.

Three benzenetellurinic mixed anhydrides, i.e., benzenetellurinyl acetate, trifluoroacetate, and trifluoromethanesulfonate, have been found to be mild oxidizing agents for various substrates such as thiol, phosphine, acyloin, α-hydroxy ester, catechol, hydroquinone, thiourea, and thioamide. The reactions towards the last two substrates are highly chemoselective, depending on both the reagent and substrate.

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