STRUCTURES OF 2 1,2,3-TRIAZINE N-OXIDES

(I) 6-Methyl-4-phenyl-1,2,3-triazine 1-oxide, C10H9N3O, M(r) = 187.2, monoclinic, Pc, a = 10.333 (1), b = 6.153 (1), c = 7.058 (2) angstrom, beta = 92.48 (2)-degrees, V = 448.2 (2) angstrom 3, Z = 2, D(x) = 1.387 Mg m-3, lambda(Cu K-alpha-1) = 1.5405 angstrom, mu = 0.782 mm-1, F(000) = 196, T = 295 K, final R = 0.036 for 656 observed reflections. (II) 4,5,6-Tris(p-tolyl)-1,2,3-triazine 2-oxide, C24H21N3O, M(r) = 367.4, monoclinic, P1, a = 9.330 (1), b = 10.073 (1), c = 5.903 (1) angstrom, alpha = 94.32 (1), beta = 98.62 (1), gamma = 113.01 (1)-degrees, V = 499.4 (1) angstrom 3, Z = 1, D(x) = 1.222 Mg m-3, lambda(Cu K-alpha-1) = 1.5405 angstrom, mu = 0.612 mm-1, F(000) = 194, T = 295 K, final R = 0.039 for 1453 observed reflections. The bond distances in the N-oxides (N+ -O-) are 1.264 (6) (I) and 1.243 (4) (II) angstrom. The dihedral angles between the triazine and phenyl rings are 22.7 (4) in (I) and 34.2 (5), 80.1 (5) and 34.5 (6)-degrees in (II).