1. An Enzyme Cascade Synthesis of ε-Caprolactone and its Oligomers.
- Author
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Schmidt, Sandy, Scherkus, Christian, Muschiol, Jan, Menyes, Ulf, Winkler, Till, Hummel, Werner, Gröger, Harald, Liese, Andreas, Herz, Hans-Georg, and Bornscheuer, Uwe T.
- Subjects
CHEMICAL synthesis ,OLIGOMERS ,OXIDATION ,PERACETIC acid ,BAEYER-Villiger rearrangement ,CYCLOHEXANONES ,ALCOHOL dehydrogenase ,OLIGOMERIZATION - Abstract
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 m M cyclohexanol. This oligomer is easily chemically polymerized to PCL. [ABSTRACT FROM AUTHOR]- Published
- 2015
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