A stereochemically safe high-yielding procedure for linking unprotected as well as protected hydroxycarboxylic acids to chiral secondary alcohols via glycolic acid linker is proposed. L-menthol has been linked with both enantiomers of mandelic, malic, and methoxyphenylacetic acid using bromo- or iodoacetyl group as a precursor of the glycolic acid linker. High-field nuclear magnetic resonance (NMR) and chiral high-performance liquid chromatography (HPLC) determination of high diastereomeric ratio (dr) (>99%) of the products bearing remote stereocenters was explored. Chiral HPLC allowed quantitation of the diastereomers up to dr 99.9/0.1. High-field NMR quantitation of the diastereomeric and parent alcoholic impurities in esters was demonstrated at the molar 0.3% and 0.03% levels, respectively. These analyses were done via comparison of integral intensities from major component (13)C satellites in (1)H or even in (13)C spectra to the (1)H or (13C signals of impurities. Despite lower sensitivity, the last option generally has much better selectivity. In this way the dynamic resolution is brought down by two orders.

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Scalable protocols of straightforward synthesis of enantiomeric γ‐(acyloxy)carboxylic acids and γ‐lactones are presented. The key step is lipase‐catalyzed stereoselective acylation of γ‐hydroxycarboxylic acid sodium salt in organic solvent followed by acidification of the product, extraction and acidic relactonization of the unreacted enantiomer. The mixture of γ‐(acyloxy)carboxylic acid and γ‐lactone is separated either by extraction with solution of sodium bicarbonate or by distillation. A switch of enantioinduction of Candida antarctica lipase B along homologous nucleophiles from R configuration of γ‐hydroxyhexanoic acid salt to S configuration of the C7 and longer‐chain homologues has been disclosed. Both enantiomers of γ‐(acyloxy)pentanoic acids; γ‐(acetyloxy)octanoic and ‐nonanoic acids with S configuration; [(1S,5R)‐5‐(chloroacetyloxy)cyclopent‐2‐en‐1‐yl]acetic acid and enantiomeric γ‐lactones derived from them were prepared with e. r. >98.5/1.5. The rates of acylation of C5 to C9 homologous salts differ by three orders of magnitude but remain applicable for preparative synthesis by variation of the enzyme loading and reaction time.