The first asymmetric synthesis of 1, 2-dioxolane-3-acetic acids is reported. Key features include the stereoselective opening of enantiomerically enriched oxetanes by hydrogen peroxide, conversion of the resulting 4-hydroperoxy-2-alkanols to 3-alkoxy-1, 2-dioxolanes, and Lewis acid mediated homologation of the latter with a thioester silyl ketene acetal. The approach is modeled on 3, 5-dimethyl-5-hexadecyl-1, 2-dioxolane-3-acetic acid (1a), an ...