The Triolide of (R)‐3‐Hydroxybutyric acid—Direct Preparation from Polyhydroxybutyrate and Formation of a Crown Estercarbonyl Complex with Na Ions

Ideally oriented to complex a metal ion, the three carbonyl groups of triolide 1 are parallel and pointing in the same direction. Upon complexation with a sodium ion, the ring adjusts by arching inward, tilting the CO groups towards each other. The preparation of triolide 1 from poly(R)-3-hydroxybutanoate is surprisingly simple.