Synthesis and Crystal Structure of 3,6- Dimethyl-9(4-nitrophenyl)-1,8-oxo-2,7,10-trioxanthene

The crystal structure of the title compound (C19H13NO7) has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 10.669(1), b = 11.544(1), c = 14.045(2) ? b = 105.98(1), V= 1663.0(3) 3, Mr = 367.30, Z = 4, Dc = 1.467 g/cm3, l = 0.71073 ? m(MoKa) = 0.114 mm-1 and F(000) = 760. The structure was refined to R = 0.0380 and wR = 0.0944 for 2093 observed reflections with I 2s(I). X-ray analysis reveals that the dihedral angles between planes 1 and 2, 1 and 3, 1 and 4, 2 and 3, 2 and 4, and 3 and 4 are 94.24, 90.66, 96.84, 3.88, 3.30 and 7.11, respectively. There exists a conjugated system in the molecular structure.