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The title compound, C19H16F4O4, was prepared by the condensation reaction of 2,6-di-fluoro-benzaldehyde and penta-erythritol. The whole mol-ecule is generated by twofold rotational symmetry. The two six-membered O-heterocycles adopt chair conformations through a shared spiro-carbon atom that is located on the crystallographic twofold rotation axis. In this conformation, the two aromatic rings are located at the equatorial positions of the O-heterocycles. The conformation of this doubly substituted tetra-oxa-spiro system is chiral. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming layers parallel to (100). These layers are linked by C-H⋯F hydrogen bonds into a three-dimensional structure.

Crystal structure ofrac-3,9-bis(2,6-difluorophenyl)-2,4,8,10-tetraoxaspiro[5.5]undecane