9-Chloro-1-methyl-7-phenyl-5,6-dihydro-13H-indolo[3,2-c]acridine

The title compound, C(26)H(19)ClN(2), 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.