2,2-Dimethyl-2,3-dihydro-1H-perimidine

The title compound, C₁₃H₁₄N₂, was obtained from reaction of diaminona­phthalene with acetone. In both independent mol­ecules in the asymmetric unit, the tricyclic perimidine consists of a planar (r.m.s. deviations = 0.0125 and 0.0181 Å) naphthalene ring system and an envelope conformation C₄N₂ ringwith the NCN group hinged with respect to the naph­thalene backbone by 36.9 (2) and 41.3 (2)° in the two independent molecules. The methyl substituents are arranged approximately axial and equatorial on the apical C atom. In the crystal, one of the N—H groups of one independent mol­ecule is involved in classical N—H...N hydrogen bonding. Short inter­molecular (C/N)—H...π(arene) inter­actions, near the short T-shaped limit, link mol­ecules in the absence of strong acceptors.