Thietanyl Protection in the Synthesis of 5-Aryloxy(sulfonyl)-3-bromo-1,2,4-triazoles

Previously unknown 5-aryloxy- and 5-benzenesulfonyl-3-bromo-1H-1,2,4-triazoles have been synthesized starting from 3,5-dibromo-1,2,4-triazole by successive alkylation with 2-chloromethylthiirane, nucleophilic substitution of the 5-bromine atom by phenoxy or phenylsulfanyl group, oxidation of the thietane sulfur atom with hydrogen peroxide, and removal of the thietanyl protecting group by treatment with sodium ethoxide.