Towards large-scale synthetic applications of Baeyer-Villiger monooxygenases

Biocatalysis is coming of age, with an increasing number of reactions being scaled-up and developed. The diversity of reactions is also increasing and oxidation reactions have recently been considered for scale-up to commercial processes. One important chemical conversion, which is difficult to achieve enantio- or enantiotopo- selectively, is the Baeyer-Villiger (BV) oxidation of ketones. Using cyclohexanone monooxygenase to catalyse the reaction produces optically pure esters and lactones with exquisite enantiomeric excess values. Recently, these enzymes and their many applications in synthetic chemistry have been explored. The scale-up of these conversions has been examined with the idea of implementing the first commercial Baeyer-Villiger monooxygenase-based process. Here, we review the state-of-the-art situation for the scale-up and exploitation of these enzymes.