Crystal structure of 2α-(1,1-di-phenyl-eth-yl)-4-methyl-4α,5α-diphenyl-1,3-dioxolane: the result of a non-acid pinacol rearrangement.

The title compound, C30H28O2, was obtained during recrystallization of (±)-1,2-diphenyl-1,2-propane-diol in 1-butanol, from an unexpected non-acid-catalyzed pinacol rearrangement followed by acetal formation of the newly formed aldehyde with the diol. The tri-substituted dioxolane ring has a twist conformation on the C-O bond opposite the methyl-substituted C atom. There is an intra-molecular C-H⋯π inter-action present involving one of the di-phenyl-ethyl rings and an H atom of the phenyl ring in position 4 of the dioxolane ring. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains along [001]. The chains are linked by a second C-H⋯π inter-action, forming sheets parallel to the bc plane.