Conversion of biobased platform chemicals to enantiopure compounds has become topical. We report a straightforward synthesis of 4-(acyloxy)-pentanoic acids from γ-valerolactone (GVL). An alkaline hydrolysis of GVL is followed by a stereoselective lipase-catalyzed acylation of the sodium salt. Acidic hydrolysis of the acylation product affords (R)-4-(acyloxy)­pentanoic acid and relactonized (S)-GVL. (R)-4-(Propionyloxy)­pentanoic acid and (R)-GVL are obtained with e.r. > 99/1. An additional enzymatic step following a slightly modified process affords (S)-4-(acetyloxy)­pentanoic acid with e.r. > 99/1. Simple access to enantiopure 4-(acyloxy)­pentanoic acids will stimulate the development of their novel applications, including biobased isotactic polymers.

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A lipase may catalyze either one or more of the three reactions of 11‐acetyl‐prostaglandin E2 in methanol‐containing reaction medium: esterification, deacetylation, and/or elimination. The catalytic performance depends on the lipase and on the methanol content. An increase in the methanol concentration in benzene from 5 % to 95 % leads to the exclusive switch of reactions from esterification to elimination catalyzed by Thermomyces lanuginosus lipase (TLL). To explain the switch, molecular dynamics simulations of solvation of TLL in benzene and in methanol were performed. Solvation in methanol leads to the closing of the lid. The repositioning of the oxyanion hole towards the catalytic triad blocks the catalysis of ester synthesis whereas enabling TLL to act as an acetyl‐β‐ketol eliminase. In benzene the lid is open, allowing esterification to occur. Docking analysis of 11‐acetyl‐prostaglandin E2 into the active site of the solvated TLL structures suggested the occurrence of reactions in accordance with the experiment.