Tandem asymmetric reactions of 1 with nucleophilic alcohols afforded optically pure spirocyclopropane derivatives with four stereogenic centers 4a-4e in 64%-88% yields with d.e.≥98%. The optically pure compounds 4a-4e were identified on the basis of their analytical data, such as [α]~D^2^0, UV, IR, ^1H NMR, ^1^3C NMR, MS and elemental analysis. The absolute configuration of the chiral spirocyclopropane compound (4a) was established by X-ray crystallography.

Key words: CYCLOPROPANE P, LACTONES, SPIRO COMPOUNDS, CRYSTAL STRUCTURE, MICHAEL ADDITION REACTION, NUCLEOPHILIC REACTION, SUBSTITUTION REACTION