Alkylation reactions of 5-amino-substituted tetrazolo[1,5-a][1,3,5]triazin-7(3H)-ones with alkyl halides

[graphic not available: see fulltext] The alkylation reactions of fused tetrazolo[1,5-a][1,3,5]triazine system were studied. The results of quantum-chemical calculations for the reaction of 5-(dimethylamino)tetrazolo[1,5-a][1,3,5]triazin-7(3H)-one with ethyl bromide are presented. The reactions of 5-aminosubstituted tetrazolo[1,5-a][1,3,5]triazin-7(3H)-ones with ethyl-, butyl-, and allyl halides led to the formation of products due to alkylation at the N-3 nitrogen atom of the ring system, 3-alkyl-5-amino-substituted tetrazolo[1,5-a][1,3,5]triazin-7(3H)-ones, as well as products due to alkylation at the exocyclic oxygen atom with tetrazole ring opening, 2-amino-substituted 6-alkoxy-4-azido-1,3,5-triazines. Besides that, the product that was alkylated at the ring N-3 nitrogen atom underwent hydrolytic cleavage of the 1,3,5-triazine ring with elimination of the carbonyl functional group and formation of N-(1-alkyl-1H-tetrazol-5-yl)-N'-alkyl- and N-(1-alkyl-1H-tetrazol-5-yl)-N',N'-dialkylguanidines.