Enantioselective Synthesis of α‐Thiocarboxylic Acids by Nitrilase Biocatalysed Dynamic Kinetic Resolution of α‐Thionitriles
Kate Lauder, Silvia Anselmi, James Finnigan, Yuyin Qi, Simon J. Charnock, Daniele Castagnolo
Abstract
The enantioselective synthesis of α-thiocarboxylic acids by biocatalytic dynamic kinetic resolution (DKR) of nitrile precursors exploiting nitrilase enzymes is described. A panel of 35 nitrilase biocatalysts were screened and enzymes Nit27 and Nit34 were found to catalyse the DKR of racemic α-thionitriles under mild conditions, affording the corresponding carboxylic acids with high conversions and good-to-excellent ee. The ammonia produced in situ during the biocatalytic transformation favours the racemization of the nitrile enantiomers and, in turn, the DKR without the need of any external additive base.
Topics & Concepts
NitrilaseRacemizationKinetic resolutionEnantioselective synthesisChemistryNitrileEnantiomerOrganic chemistryCombinatorial chemistryCatalysisSulfur-Based Synthesis TechniquesEnzyme Catalysis and ImmobilizationChemical Synthesis and Reactions