An alternative approach towards poly-ε-caprolactone through a chemoenzymatic synthesis: combined hydrogenation, bio-oxidations and polymerization without the isolation of intermediates

Journal
Green chemistry  
Volume
19
Issue
5
Start Page
1286
End Page
1290
Citation
Green Chemistry 5 (19): 1286-1290 (2017-06-01)
Publisher DOI
10.1039/c6gc02529c
Scopus ID
2-s2.0-85021182382
Publisher
RSC
A novel synthetic route towards the polymer poly-ε-caprolactone based on a chemoenzymatic reaction sequence was developed. Initial hydrogenation of phenol to cyclohexanol gave a crude product, which was directly used without work-up for a subsequent biocatalytic double oxidation towards ε-caprolactone by means of an alcohol dehydrogenase and a monooxygenase. In order to overcome product inhibition effects, an in situ-product removal strategy via extraction of ε-caprolactone from an aqueous reaction medium with an organic solvent in the presence of a permeable polydimethylsiloxane membrane was applied. Furthermore, this in situ-product removal was combined with lipase-catalyzed polymerization in the organic phase at 25 °C. The obtained crude product contained a polymer fraction with a degree of polymerization comparable to commercial poly-ε-caprolactone.
DDC Class
540: Chemie
620: Ingenieurwissenschaften