Synthesis of (S)-α-tocotrienol via an enzymatic desymmetrization of an achiral chroman derivative

The stereoselective acylation of an achiral chromandimethanol derivative by vinyl acetate in the presence of Candida antarctica lipase in organic media gave the corresponding (S)-monoester in high enantiomeric purity (ee=98%). (S)-α-Tocotrienol was synthesized in 19% overall yield over six steps from this (S)-monoester.