Exploring the substrate scope of Baeyer-Villiger monooxygenases with branched lactones as entry towards polyesters

Baeyer-Villiger monooxygenases (BVMOs) are biocatalysts able to convert cyclic ketones to lactones by the insertion of oxygen. The aim of this study was to explore the substrate scope of several BVMOs with (biobased) cyclic ketones as precursors for the synthesis of branched polyesters.The product structure and the degree of conversion of several biotransformations was determined after conversions using self-sufficient BVMOs. Full regioselectivity towards the normal lactone of jasmatone and menthone was observed, while the oxidation of other substrates such as α,β-thujone and 3,3,5-trimethylcyclohexanone resulted in mixtures of regio-isomers. This exploration of the substrate scope of both established as well as newly discovered BVMOs towards biobased ketones contributes to the development of branched polyesters from renewable resources.