7,8,9,10-Tetra­hydro-2-methyl­cyclo­hepta­[b]indol-6(5H)-one

The title compound, C(14)H(15)NO, was synthesized from 2-hydroxy­methyl­enecyclo­hepta­none 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 inter­actions (the centers of the atoms involved in the stacking interaction are separated by 3.504 Å) give rise to another type of centrosymmetric dimer. In combination, these inter­actions create a stair-like chain of mol­ecules that inter­acts only loosely with neighboring chains via van der Waals inter­actions and weak C—H⋯π contacts.