STRUCTURES OF THE ISOMERIC TRIAZENE 1-OXIDES 3-(4-ETHOXYCARBONYLPHENYL)-1-METHYLTRIAZENE 1-OXIDE (1) AND 3-(2-ETHOXYCARBONYLPHENYL)-1-METHYLTRIAZENE 1-OXIDE (2)

3-(4-Ethoxycarbonylphenyl)-1-methyltriazene 1-oxide (1), C10H13N3O3, M(r) = 223.2, monoclinic, P2(1)/c, a = 5.5055 (13), b = 25.2007 (25), c = 8.1241 (19) angstrom, beta = 100.434 (I 1)-degrees, V = 1108.5 angstrom3, Z = 4, D(x) = 1.34 g cm-3, lambda(Mo Kalpha) = 0.70926 angstrom, mu = 0.9 cm-1, F(000) = 472, T = 290K, R = 0.044 for 1080 unique observed reflections. 3-(2-Ethoxycarbonylphenyl)-l-methyltriazene I-oxide (2), C10H13N3O3, M(r) = 223.2, monoclinic, P2(1)/c, a = 12.963(9), b = 8.1716(8), c = 11.212(7) angstrom, beta = 110.85 (3)-degrees, V = 1109.9 angstrom, Z = 4, D(x) = 1.34 g cm-3, lambda(Mo Kalpha) = 0.70926 angstrom, mu = 0.9 cm-1, F(000) = 472, T = 290 K, R = 0.070 for 1192 unique observed reflections. Both structures adopt the N-oxide tautomeric form which is in agreement with spectroscopic evidence and previously reported crystal structures of 3-(4-carbamoylphenyl)triazene 1-oxides.