Conversions by dimethyldioxirane of 1-alkylbenzotriazoles into their N-oxides and of 2-alkylbenzotriazoles into 2-alkyl-trans-4,5,6,7-diepoxy-4,5,6,7-tetrahydrobenzotriazoles.

Dimethyldioxirane converted 1-alkylbenzotriazoles 4 to the corresponding 3-alkylbenzotriazole 1-oxides 5 in good yields, but transformed 2-alkylbenzotriazoles 12 into 2-alkyl-trans-4,5,6,7-diepoxy-4,5,6,7-tetrahydrobenzotriazoles 13.