A Short Synthesis of (<i>S</i>)‐5‐Hydroxy‐2‐penten‐4‐olide from <scp>D</scp>‐Mannitol via 2,3‐<i>O</i>‐Isopropylidene‐<scp>D</scp>‐glyceraldehyde

Abstract

Abstract ( S )‐5‐Hydroxy‐2‐penten‐4‐olide ( 5 ) was synthesized in three steps starting from D ‐mannitol bis(acetonide) ( 1 ), via D ‐glyceraldehyde acetonide ( 2 ) by Z ‐selective Wittig reaction, acid‐catalyzed lactonization and crystallization with a total yield of 40%.