3-(5,6,7,8-Tetra­hydro-2-naphth­yl)iso­benzofuran-1(3H)-one

The title compound, C(18)H(16)O(2), was prepared by reduction of 2-(5,6,7,8-tetra­hydro-2-naphtho­yl)benzoic acid with zinc dust. The benzene ring in the tetra­hydro­naphthyl substituent is nearly perpendicular to the plane of the isobenzofuran-1(3H)-one ring [87.15 (4)°]. The cyclo­hexane unit has a half-chair conformation in which two methylene groups in the tetra­methyl­ene bridge are disordered over two positions; the site-occupancy factors are 0.838 (4) and 0.162 (4). The crystal structure exhibits alternating isobenzofuran-1(3H)-one and tetra­hydro­naphthalene layers.