Collect. Czech. Chem. Commun. 1991, 56, 1690-1700

Preparation of optically pure enatiomers of Corey lactone by resolution of the racemate

Bohumil Žáka, Ivan Veselýa, Karel Neumitkaa and Jaroslav Palečekb

a Research and Development Division, Chemical Works Spolana, 277 11 Neratovice
b Department of Organic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6


Racemic hydrogen butanedioates (IIa, IIb) and hydrogen pentanedioates (IIIa, IIIb), prepared by reaction of racemic Corey alcohols Ia, Ib with the corresponding acid anhydride, were resolved by optically active bases [(1R,2S)-(-)-ephedrine, (S)-(-)-1-phenylethylemine, quinine] to give the optically pure diastereoisomeric salts from which the individual enantiomers of hydrogen butanedioate IIa and IIb and hydrogen pentanedioate IIIa and IIIb were liberated. Acid-catalyzed transesterification with methanol converted these optically pure enantiomers into pure(-)-enantiomer Ia and (+)-enantiomer Ib of the Corey lactone.