Crystal structure of (E)-4-ethyl-2-(4-meth-oxy-benzyl-idene)-3,4-di-hydro-naphthalen-1(2H)-one.

In the title compound, C20H20O2, the exocyclic C=C double bond has an E conformation. The ethyl substituent on the cyclo-hexa-none ring is in an axial orientation. The cyclo-hexa-none ring adopts a screw-boat conformation, with the methyl-ene C atom and the C atom bearing the 4-meth-oxy-benzyl-idene group displaced from the other atoms by 0.812 (1) and 0.334 (1) Å, respectively. The dihedral angle between the planes of the benzene rings is 42.20 (8)°. In the crystal, no directional inter-actions beyond van der Waals contacts are observed.