The reactions of nitrile oxides with S,S-dimethyl-N-(2,4,6-trihalophenyl)sulfimides gave unusual products, which structure was determined to be 2-aryl-4,6-dihalobenzoxazoles from their elementary analyses and spectral data. While the reactions with S,S-dimethyl-N-(2-bromophenyl)- or S,S-dimethyl-N-(2,4-dibromophenyl)sulfimide gave 1,2,4-benzoxadiazine derivatives. A plausible reaction mechanism for