Racemic Resolution of Nitrile Ester

The first enzymatic reaction investigated in the whole project concerned the introduction of chirality in route B (Fig. 2) by generation of succinic acid mononitrile (R)-12 from its racemic precursor. Since in a broad sense the nitrile ester substrate 10 can be interpreted as an amino acid analogue, proteases recommended themselves as catalysts to be tested. From the literature, 2-substituted succinic and butyric acid esters were known to be resolved by proteases [6, 7]. Proteases are 

Solvent added or salt used (instead of NaC ) °c Time for 40% conversion (min) % ee (R)-12 

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