SYNTHESIS OF BRIDGEHEAD-FUNCTIONALIZED BICYCLO[3.2.1]OCTANES VIA INTRAMOLECULAR TITANIUM-INDUCED AND TRIBUTYLSTANNANE-INDUCED PINACOL COUPLING

The synthesis of the enantiomerically pure, bridgehead-functionalized bicyclo[3.2.1]octanes 11 and 16, containing a conformationally fixed t rihydroxypropyl (aminodihydroxypropyl) unit, as well as the X-ray stru cture of 11 are described. These compounds are of interest as sugar su rrogates in the preparation of DNA analogs. Compounds 11 and 16 became available in 10 and 12 steps, respectively, and in an overall yield o f 11 and 4% from D-arabinose via a highly stereoselective pinacol coup ling as the key-step.