Acid Catalyzed tert-Butylation and Tritylation of 4-Nitro-1,2,3-triazole: Selective Synthesis of 1-Methyl-5-nitro-1,2,3-triazole via 1- tert-Butyl-4-nitro-1,2,3-triazole.

4-Nitro-1,2,3-triazole was found to react with tert-butanol in concentrated sulfuric acid to yield 1- tert-butyl-4-nitro-1,2,3-triazole as the only reaction product, whereas tert-butylation and tritylation of 4-nitro-1,2,3-triazole in presence of catalytic amount of sulfuric acid in benzene was found to provide mixtures of isomeric 1- and 2-alkyl-4-nitro-1,2,3-triazoles with predominance of N2-alkylated products. A new methodology for preparation of 1-alkyl-5-nitro-1,2,3-triazoles from 1- tert-butyl-4-nitro-1,2,3-triazole via exhaustive alkylation followed by removal of tert-butyl group from intermediate triazolium salts was demonstrated by the example of preparation of 1-methyl-5-nitro-1,2,3-triazole. [ABSTRACT FROM AUTHOR]