Date Published: May 01, 2009
Publisher: International Union of Crystallography
Author(s): Makuteswaran Sridharan, Karnam J. Rajendra Prasad, Matthias Zeller.
The title compound, C26H19ClN2, is a 5,6-dihydro-13H-indolo[3,2-c]acridine prepared by condensation of a 2,3,4,9-tetrahydro-1H-carbazol-1-one with 2-aminobenzophenone. The crystals undergo a destructive phase change upon cooling at varying temperatures between 270 and 200 K, depending on cooling rate and disturbance by vibration, thus indicating supercooling of the metastable room-temperature structure at lower temperature. The overall planarity of the indolo[3,2-c]acridine part of the molecule is interrupted by the saturated ethylene group, and the planes of the two halves exhibit a dihedral angle of 22.05 (6)° with each other while themselves being essentially planar. Packing is dominated by C—H⋯π interactions. No classical hydrogen bonds or stacking interactions are observed.
For general background on the synthesis and properties of carbazole derivatives, see: Knölker & Reddy (2002 ▶); Choi et al. (2008 ▶). For synthesis and structures of indoloacridines, see: Sridharan et al. (2009a ▶,b ▶). For pharmacologically active constituents (especially carbazole alkaloids) of Murraya koenigii spreng, see: Iyer & Devi (2008 ▶).