Pyrimidine N-oxides. Oxidation of 5-nitroso-2,4,6-triaminopyrimidine

The peroxytrifluoroacetic acid oxidation of 5-nitroso-2,4,6-triaminopyrimidine ( 1b ) led to the formation of two products: 5-nitro-2,4,6-triaminopyrimidine 1-N-oxide ( 2 ) and 5-nitro-2,4,6-triaminopyrimidine 1-3-di-N-oxide ( 3 ). On the basis of previous experience 2 was the sole expected oxidation product. However, 3 represents a rather unexpected development in that di-N-oxides in the pyrimidine series are uncommon. The yields are good for both products and structures are assigned on the basis of elemental analysis, mass spectral data, and chemical reactions. The reaction sequence is also discussed.