New Route to 4-Aminocyclopent-2-en-1-ols: Synthesis and Enantioselective Rearrangement of 4-Amino-substituted Cyclopentene Oxides

A new route for the asymmetric synthesis of 4-aminocyclopent-2-en-1-ols (90% ee) for carbocyclic nucleoside analogue synthesis is described. The approach involves the stereoselective preparation of cis 4-amino-substituted cyclopentene oxides and subsequent chiral base-mediated rearrangement to the corresponding allylic alcohols. Full details on the synthesis and stereoselectivity of epoxidation of 4-amino-substituted cyclopentenes are presented.