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A general and efficient preparation of epimeric optically pure γ-butyrolactones 2 and 3 is described starting from l-tartaric acid (1). These lactones are well-known to be important building blocks in the syntheses of natural products. l-Tartaric acid (1) was transformed into carbonylated chirons (ketones 4 and aldehyde 5). These chirons, when submitted to highly stereoselective reactions (reduction or organometallic addition), led to epimeric dihydroxy γ-butyrolactones 2 and 3 after lactonization and deprotection steps. The resulting optically pure lactones are precursors of biological compounds and have allowed a total synthesis of l-biopterin and formal syntheses of quercus lactone, dodecanolactone, avenaciolide, and tetrahydrocerulenin.

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The use of chiral alkoxides obtained from ephedrines for enantioselective proton abstraction is described in full. These reagents allow the practical obtention of axially dissymmetric 1,3-dioxanes via highly enantioselective dehydrohalogenation reactions. The conditions for a catalytic use of these chiral alkoxides are defined.

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