3-Amino-5-nitro-1,2,4-triazole, relative

The molecule of 4-amino-2-methyl-5-nitro-l,2,3-triazole 1-oxide is nearly planar, except that the hydrogen atoms of the methyl group deviate from the ring plane by 0.505, 0.918, and 0.324 A [175], Coplanarity of the nitro group with the ring plane (1.8°) is caused by intramolecular hydrogen bond O...H...N (the O...N distance is 2.851 A). This fact also explains an elongation of N6-O8 bond (1.233 A) relative to N6-07 (1.225 A). 

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