Studies on the Sharpless Asymmetric Epoxidation of Unsymmetrical Divinylmethanols.

A reaction of racemic unsymmetrical divinylmethanol rac-13 under the Sharpless asymmetric epoxidation conditions using stoichiometric amounts of titanium tetraisopropoxide [Ti(OPi)4], D-(–)-diisopropyl tartrate (DIPT) and tert-butyl hydroperoxide (TBHP) afforded R-14 and R-15 in 41 and 43% yield, each with > 99%ee, respectively, where the kinetic resolution and subsequent epoxidation had proceeded in an entirely regio- and diastereo-selective manner.