作者:T. P. Kofman
DOI:10.1023/a:1013100716588
日期:——
Heterylation of 3-R-1-5-R-2-1,2,4-triazoles (pK(a) 3-12) with N-alkyl-, N-alkenyl-, N-alkoxycarbonyl-, N-oxoalkyl-, N-nitroxyalkyl, and N-nitroaminoalkyl-3,5-dinitro-1,2,4-triazoles results in substitution of a nitro group in 5 position of the dinitro compound yielding 1-R-methyl-3-nitro-5-(3-R-1-5-R-2-1,2,4-triazolyl)-1,2,4-triazoles. The side processes: Hydroxide-ion attack on C-5 and (or) N-1 of the ring both in the substrate and in the target compound afford 1-R-methyl-3-nitro-1,2,4-triazol-5-ones, 3,5-dinitro-1,2,4-triazole and NH-acids of N-C-bitriazole series. Optimal reaction media are aprotic dipolar substances, and for compounds prone to heterolysis ethyl acetate-water systems. The azole pK(a) is the decisive factor controlling the composition and the ratio of reaction products. The process is promising for azoles with pK(a) > 5, and the optimal range of pK(a) is 8-10.