Exquisite use of Selenoesters as Recyclable Acyl Donors for Lipases-catalyzed Kinetic Resolution

Lipase-catalyzed enantioselective synthetic reactions employing enol esters, activated esters, anhydrides, and oximes as acyl donors is a well-consolidated strategy towards enantiopure compounds. However, lipases can also cleave the C-S bond of thioesters, proving that other classes of substances can be used as acyl donors in lipase-catalyzed transformations. Herein we describe the application of selenoesters as a new class of acyl donors in enzymatic kinetic resolution of chiral alcohols. A series of selenoesters was successfully employed in the resolution of chiral primary and secondary alcohols, demonstrating that lipases can also cleave the C-Se bond. Assays using selenoesters as acyl donors in lipase-catalyzed reactions furnished enantiopure compounds (e.e.>99 %) and enantiomeric ratio (E>200). We also observed that the enzymatic reaction is accelerated in an oxygen atmosphere and performing a preparative scale reaction could demonstrate how simple and easy the purification process is to recover the diselenide formed during the resolution.

Automated summary

This study demonstrates the use of selenoesters as acyl donors in lipase-catalyzed enzymatic kinetic resolution of chiral alcohols. The results show that lipases can effectively cleave the C-Se bond of selenoesters, leading to the successful synthesis of enantiopure compounds. The enzymatic reaction is accelerated in an oxygen atmosphere, and the purification process is simple and easy.