The title compound, C17H13ClO, is the second monoclinic polymorph to crystallize in the space group P21/c. The first polymorph crystallized with two independent mol-ecules in the asymmetric unit [Bolognesi et al. (1975 ▸). Acta Cryst. A31, S119; Z' = 2; no atomic coordinates available], whereas the title compound has Z' = 1. In the title polymorph, the dihedral angle between the plane of the benzene ring of the tetra-lone moiety and that of the 4-chloro-benzyl ring is 52.21 (11)°. The cyclo-hex-2-en-1-one ring of the tetra-lone moiety has a screw-boat conformation. In the crystal, mol-ecules are liked by pairs of C-H⋯π inter-actions forming inversion dimers. There are no other significant inter-molecular inter-actions present.
Keywords: C—H⋯π interactions; crystal structure; α-tetralone.