7,8,9,10-Tetra-hydro-2-methyl-cyclo-hepta-[b]indol-6(5H)-one.

The title compound, C(14)H(15)NO, was synthesized from 2-hydroxy-methyl-enecyclo-hepta-none via a Japp-Klingemann acid-catalyzed cyclization. The seven-membered ring exhibits a slightly distorted envelope conformation. N-H⋯O hydrogen bonds form a centrosymmetric dimer; C-H⋯O hydrogen bonds and π-π stacking inter-actions (the centers of the atoms involved in the stacking interaction are separated by 3.504†à ) give rise to another type of centrosymmetric dimer. In combination, these inter-actions create a stair-like chain of mol-ecules that inter-acts only loosely with neighboring chains via van der Waals inter-actions and weak C-H⋯π contacts.