Intramolecular haloetherification of the ene acetals prepared from chiral non-racemic C₂-symmetric diols and achiral 4-pentenal or 5-heptenal proceeded in diastereoselective manners to form two asymmetric centers. The reaction was applied to synthesize optically active 1,4- and 1,5-diols. On the other hand, intramolecular haloetherification of diene acetals proceeded in two different manners. The intramolecular haloetherification of the diene acetals, prepared from chiral hydrobenzoin and σ-symmetric cyclohexa-1,4-dienes, proceeded with one olefin in a diastereoselective manners and gave the compounds having one remained olefin. However, the reaction of the acyclic diene acetals, prepared from hydrobenzoin and σ-symmetric 1,7-dienes, occurred novel double haloetherification giving four newly formed chiral stereocenters. The developed reactions were applied to synthesize optically active natural products, a civet constituent, scyphostatin, (+)-Sch 642305, rublenolide and rubrynolide.