TWINNED CRYSTAL-STRUCTURE OF Y-4,4-DIMETHYL-6-OXO-1-CYCLO-HEXENYL)PHENYLMETHANE AT 150 K

The title compound, ne)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one), C23H28O4, forms tetragonal crystals twinned on (110). The two molecul es in the asymmetric unit differ only in the conformation of one of th e two cyclohexenone rings which both display the expected envelope con formation; while three apices are extended towards the phenyl ring, on e is directed away from it. The molecules form two strong intramolecul ar hydrogen bonds connecting the two cyclohexenone rings. The X-ray st ructure analysis was undertaken in order to ascertain the nature of th e reaction product.