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

The title compound, C(13)H(14)N(2), was obtained from reaction of diaminona-phthalene with acetone. In both independent mol-ecules in the asymmetric unit, the tricyclic perimidine consists of a planar (r.m.s. deviations = 0.0125 and 0.0181†à ) naphthalene ring system and an envelope conformation C(4)N(2) ringwith the NCN group hinged with respect to the naph-thalene 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 mol-ecule is involved in classical N-H⋯N hydrogen bonding. Short inter-molecular (C/N)-H⋯π(arene) inter-actions, near the short T-shaped limit, link mol-ecules in the absence of strong acceptors.