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.

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► 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.