Spiro[indene-1,1′-benzo[e]indolin]-2′-one

Abstract

In the title compound, C20H13NO, the indene ring is disordered over two sites with an occupancy ratio of 0.557 (2):0.443 (2). Both disordered components of indene are nearly perpendicular to the naphthalene ring system, making dihedral angles of 90.9 (2) and 85.0 (5)°. The five-membered ring of the 1H-pyrrol-2(3H)-one adopts an envelope conformation with the spiro C atom at the flap position. Intermolecular classical N—H...O and weak C—H...O hydrogen bonding is present in the crystal structure.