7-Benzyl-2,7-diaza-spiro-[4.4]nonan-1-one.

In the title compound, C(14)H(18)N(2)O, both the spiro-linked five-membered rings adopt envelope conformations, with a C atom as the flap in one ring and an N atom in the other. The dihedral angle between the two four-atom planes is 80.46†(8)°. In the crystal, the mol-ecules are linked by N-H⋯O hydrogen bonds to generate C(4) chains propagating in [010].