Asymmetric construction of quaternary carbon centers by titanium-mediated stereospecific allylation of 2,3-epoxy alcohol derivatives

A general procedure for the asymmetric construction of a quaternary carbon center from readily available 2,3-epoxy alcohol derivatives was developed. Ring-opening reaction of 2-substituted 2,3-epoxy alcohol derivatives with a reagent prepared from allylmagnesium halide and chlorotitanium triphenoxide affords allylated 1,3-diols having a chiral quaternary carbon as a single isomer by the anti pathway.