Abstract
In molecules of C15H10Cl3NO, the four-membered lactam ring is nearly planar, with a C-N bond length of 1.367(4) Angstrom in the amide group and C-C distances of 1.535(5) and 1.566(5) Angstrom. The displacement of the amide N atom from the plane through the atoms attached to it is 0.056(3) Angstrom, indicating some pyramidal character which is correlated to the biological activity in related compounds. The phenyl rings are nearly perpendicular to one another [dihedral angle 79.4(1)degrees]. There are intramolecular and intermolecular hydrogen bonds in the structure.