DIASTEREOSELECTIVE MANIPULATIONS OF BICYCLO[M.1.0]ALKANE DERIVATIVES .2. NUCLEOPHILIC ADDITIONS TO THE CARBONYL CARBONS OF BICYCLO[M.1.0]ALKAN-2-ONES

Enantiomerically enriched bicyclo[m.1.0]alkan-2-ones having larger rin g sizes between five and 16 members were prepared and subjected to add itions of nucleophiles to the carbonyl carbon. Such additions were eff icient and highly diastereoselective for all nucleophiles for bicycles with ring sizes greater than seven. Diastereoselectivity for these ad ditions is rationalized by assuming early transition states and exposu re of the same carbonyl face to the ring exterior in the vast majority of populated conformers for each bicyclic ketone.