Optimised Dynamic Kinetic Resolution of benzoin by a chemoenzymatic approach in 2-MeTHF

Different influential parameters in the Dynamic Kinetic Resolution of racemic benzoin via lipase–ruthenium catalyst enantioselective transesterification have been improved in order to develop a more productive process. In this sense, 2-Methyltetrahydrofuran (2-MeTHF) is proposed as an excellent and greener substitute of THF for this biotransformation; on the other hand, by scaling up the reaction, much better results were obtained by using a much simpler one-pot methodology (compared to the previously described three-steps protocol), resulting not only in higher amounts of enantiopure product (85% conversion, >99% ee of the product), but also in an enhanced sustainability of the process, because lower acyl donor concentrations and lower ruthenium catalyst amounts (protected from oxygen deactivation) are required.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Enantiopure α-hydroxyketone esters in high yields. ► 2-MeTHF as an excellent green substitute of THF in biocatalysis. ► Lipase–ruthenium catalyst combination. ► Optimised DKR for better productivity.