The ORTEP diagram of the molecule showing ellipsoids at the 50% probability level.

8-(Biphenyl-4-yl)-8-hydroxypentacyclo[5.4.0.0^2,6.0^3,10.0^5,9]undecan-11-one ethylene ketal

Acta Cryst. (2008). E64, o283 [doi:10.1107/S1600536807065920]

The pentacycloundecane cage structure has been the subject of numerous crystallographic studies. The skeleton is known to have C–C bond angles and lengths that vary significantly from normal values. The title molecule, which exists as a racemate, was synthesised as part of an ongoing investigation into chiral cage derivatives as potential asymmetric catalysts. The molecule exhibits intramolecular hydrogen bonding as well as a complex network of weak van der Waals interactions between neighbouring molecules.