Stereoselective synthesis of highly functionalized nitrocyclopropanes through the organocatalyic Michael-addition-initiated cyclization of bromonitromethane and β,γ-unsaturated α-ketoesters.

A highly diastereo- and enantioselective cyclopropanation of β,γ-unsaturated α-ketoesters with bromonitromethane has been successfully developed through a domino Michael-addition/intramolecular-alkylation strategy. Acceptable yields (up to 89%) and enantioselectivities (up to 96% ee) have been obtained.