3.5- diamino-4-nitropyrazole

Poullain and co-workers ° synthesized Af-substituted-3,5-diamino-4-nitropyrazoles by treating substituted pyrimidines with Af-alkylhydrazines. 3,5-Diamino-4-nitropyrazole (14) has been synthesized by treating the pyrimidine (13) with hydrazine hydrate. This methodology is limited in scope but the products are useful intermediates for the synthesis of insensitive high explosives. 

Nitroketene aminals react with organic thiocyanates to form the amides of /J/)-bis-amino-a-nitrothioacrylic acid [501], The latter proved valuable starting compounds for the synthesis of various heterocycles [502], It was not possible to obtain nitropy-razoles by the direct action of hydrazine hydrate on these amides [502,503], However, the corresponding derivatives of 3,5-diamino-4-nitropyrazole were synthesized after previous methylation of the hydrazine hydrate with methyl iodide or dimethyl sulfate (without isolating the 5-methyl intermediate) [504] (Scheme 75). 

Substituted 3,5-diamino-4-nitropyrazole 4,4 -Dinitro-1,1 -methylenedipyrazole 3-Nitropyrazole and its 1-, 4-, and 5-derivatives JV-nitropyrazoles... 

Diamino-2-nitroacrylonitriles react with hydrazine to give 3,5-diamino-4-nitropyrazoles (49, 50) in high yields.44 The reaction has been carried out with compounds containing identical amino groups [Eq. (15)], or with cyclic compounds derived from ethylenediamine [Eq. (16)]. 

Nitro-l,2,4-triazole (45%) [451] and l-methyl-4-cyano-5-nitropyrazole (42%) [452] were isolated during the oxidation of corresponding aminoazole derivatives by a solution of hydrogen peroxide in trifluoroacetic acid. One of the amino groups in l-acyl-3,5-diamino-l,2,4-triazole is oxidized by hydrogen peroxide in the presence of sodium tungstate [453] (Scheme 59). 

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