Conformation of dihydropentahelicenediol 2 and the related compounds was studied. Two isolable conformers, i.e. the diequatorial and the diaxial forms, interconvert only at elevated temperatures, where the equilibrium ratio depends on bulkiness of the substiments attached to the hydroxy groups. The palladium-catalyzed asymmetric allylic substitution was used to test the potential utility of phosphine derivatives, 6eq and 6ax, as chiral ligands.