| Abstract
| - Optically active allylic alcohols can be prepared via rearrangement of epoxides using chiral lithiumamides, but other than for a small subset of meso-epoxides, insufficient reactivity and enantioselectivity hamperthe existing methods. Furthermore, the chiral reagents are often required in large excess. This study presentsa general and highly enantioselective process that, in addition, is based on catalytic amounts (5 mol %) ofenantiopure (1S,3R,4R)-3-(1-pyrrolidinyl)methyl-2-azabicyclo[2.2.1]heptane and lithium diisopropylamide asthe stoichiometric base. The influence of structural modification of the catalyst is studied in terms of activity,enantioselectivity, and aggregation behavior. The utility of the process is demonstrated by its application to avariety of epoxide derivatives (≥94% ee for 11 out of 14 examples), including the formal syntheses of, e.g.,a prostaglandin core unit, epibatidine, carbovir, faranal, and lasiol. The system is readily extended to theresolution of racemic epoxides, which allows access to highly enantioenriched epoxides or allylic alcohols,even at conversions near 50%.
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