Poly-ε-caprolactone (PCL) is chemically produced on an industrial scale in spite of the need for hazardous peracetic acid as an oxidation reagent. Although Baeyer-Villiger monooxygenases (BVMO) in principle enable the enzymatic synthesis of ε-caprolactone (ε-CL) directly from cyclohexanone with molecular oxygen, current systems suffer from low productivity and are subject to substrate and product inhibition. The major limitations for such a biocatalytic route to produce this bulk chemical were overcome by combining an alcohol dehydrogenase with a BVMO to enable the efficient oxidation of cyclohexanol to ε-CL. Key to success was a subsequent direct ring-opening oligomerization of in situ formed ε-CL in the aqueous phase by using lipase A from Candida antarctica, thus efficiently solving the product inhibition problem and leading to the formation of oligo-ε-CL at more than 20 g L(-1) when starting from 200 mM cyclohexanol. This oligomer is easily chemically polymerized to PCL.

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All nor(pseudo)ephedrine isomers can be synthesized step-efficiently in two different 1-pot 2-step biocatalytic cascade reactions in high optical purities.

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The synthesis of enantiopure amines via amine transaminases involves several challenges including unfavorable reaction equilibria and product inhibition. Described here is a non‐catalytic approach to overcome such problems by using an in situ‐product crystallization (ISPC) to selectively remove a targeted product amine from an amine transaminase‐catalyzed reaction. The continuous removal of the product amine from its reaction solution as a barely soluble salt effectively yields a displacement of the reaction equilibrium towards the products and facilitates a simple downstream processing approach via filtration. The targeted product amine is eventually obtained from the salt, while the counterion compound can be easily recycled.