A simple and practical approach to enantiomerically pure (S)-3-hydroxy-γ-butyrolactone: synthesis of (R)-4-cyano-3-hydroxybutyric acid ethyl ester

The oxidation of α- or β-(1,4) linked disaccharides or oligosaccharides with cumene hydroperoxide in the presence of a base gave (S)-3,4-dihydroxybutyric acid, which was cyclized under acidic conditions to furnish (S)-3-hydroxy-γ-butyrolactone. This was subsequently converted into (R)-cyano-3-hydroxybutyric acid ethyl ester, an intermediate for statin based drugs and other related compounds.

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(S)-4-Hydroxydihydrofuran-2-oneC4H6O3[α]D25=-84.6 (c 3.1, EtOH)Source of chirality: chiral starting materialAbsolute configuration: (S)

(S)-4-Bromo-3-hydroxybutyric acid ethyl esterC6H11BrO3[α]D25=-10 (c 1.2, EtOH)Source of chirality: chiral starting materialAbsolute configuration: (S)

(R)-4-Cyano-3-hydroxybutyric acid ethyl esterC7H11NO3[α]D25=-32.5 (c 1, CHCl3)Source of chirality: chiral starting materialAbsolute configuration: (R)