| Abstract
| - Two short and convergent routes have been devised for the preparation of enantiomerically pureacyclic epoxy vinyl sulfoxides. These substrates undergo highly regio- and stereoselective SN2‘displacements with lithium cyanocuprates to give α‘-alkylated, γ-oxygenated Z α,β-unsaturatedsulfoxides in moderate to good yields and with good to excellent diastereoselectivities. The absoluteconfiguration of the newly formed carbon−carbon bond is primarily controlled by the chiral sulfuratom, which in a nonreinforcing situation can override the intrinsic anti tendency of the vinyl oxiranemoiety and forces the cuprate to undergo syn addition. The hydroxy vinyl sulfoxide functionalityof the resulting adducts should allow for subsequent asymmetric transformations thus enhancingthe synthetic usefulness of this methodology.
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