Synthesis of the trans-hydrindane core of dictyoxetane

A concise, stereoselective synthesis of the trans-hydrindane core of the marine natural product dictyoxetane is reported, starting from a Robinson annelation derived bicyclic enone. A phosphorane-mediated, pinacol-like rearrangement of a cis-diol, via a formal 1,2-hydride shift, is used to establish the requisite trans ring junction. P-31 NMR supports the formation of the intermediate phosphorane, generated in situ from the reaction of a diol with Ph3PCl2.