METHYLATION AND AMINATION OF 4H-[1,2,3]TRIAZOLO[4,5-c][1,2,5]OXADIAZOLE SALTS

The methylation and the amination of 4H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole salts (K+, Ag+, Et3NH+, DBUH+) were studied for the first time. It is shown that two methylated products are formed in the reaction. In the case of K- and Et3N-salts, 4- and 5-methylated isomers are formed in equal proportions, and in the case of Ag- and DBU-salts, the main product is the 4-isomer. It was found that the main product of amination of both 4H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole K- and DBU-salts with O-(p-tolylsulfonyl)hydroxylamine is 4-azido-3-amino-1,2,5-oxadiazole. The mechanism of its formation as a result of rearrangement of 5-amino-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole is proposed.